Klebsiella

Microb Drug Resist, 2004 Winter, 10(4), 359 - 63
Recurrent Klebsiella pneumoniae mycotic aneurysm in a diabetic patient and emergence of an extended-spectrum beta-lactamase (CTX-M-24)-containing Klebsiella pneumoniae strain after prolonged treatment with first-generation cephalosporins for mycotic aneurysm; Lee CH et al.; A 68-year-old diabetic woman suffered from mycotic aneurysm due to Klebsiella pneumoniae over her abdominal aorta; she received surgical intervention, followed by treatment with first-generation cephalosporins for 6 months . She was hospitalized again 11 months later because of another episode of mycotic aneurysm caused by K . pneumoniae on her thoracic aorta . Fingerprinting generated by pulsed-field gel electrophoresis and infrequent-restriction-site polymerase indicated K . pneumoniae isolates of the identical clonal strain were responsible for these two mycotic-aneurysm episodes . Unfortunately, nosocomial pneumonia developed at the second hospitalization; blood and purposefully sampled feces specimen cultures both grew CTX-M-24-producing K . pneumoniae, which were of the same strain and genetically nonrelated to the K . pneumoniae strain causing mycotic aneurysms earlier . This is the first report on infection due to CTX-M-24-producing K . pneumoniae . It is unclear whether the prolonged use of first-generation cephalosporins in this case selected a strain of enteric organism possessing the ESBL in question, which was capable of passing this ESBL plasmid to the K . pneumoniae strain causing the nosocomial infection . This report suggests that further observation is needed before one can draw a conclusion on the possibility of the selection of ESBL enteric organism by extensive exposure to first-generation cephalosporins.

Microb Drug Resist, 2004 Winter, 10(4), 354 - 8
Outbreak of SHV-5 beta-lactamase-producing Klebsiella pneumoniae in a neonatal-pediatric intensive care unit in Spain; Brinas L et al.; The objective was to analyze the beta-lactamase genes and the clonal relationship in a series of 12 clinical Klebsiella pneumoniae strains resistant to ceftazidime or cefotaxime (MIC >/=16 microg/ml) recovered in the neonatalpediatric intensive care unit (ICU) ward of a Spanish hospital during a 1-year period . TEM, SHV, CTX-M, CMY, or FOX beta-lactamase genes were analyzed by PCR and sequencing . The clonal study was performed by pulsed-field gel electrophoresis (PFGE) using XbaI . All but one of the 12 K . pneumoniae strains harbored the bla (SHV-5) gene, and the bla TEM-1a gene was also detected in one of them . These 11 strains belonged to two different clonal types: A (9 strains) and B (2 strains) and were grouped in the subtypes A(1) (6 strains), A(2), A(3), A(4), B(1), and B(2) (1 strain each) . The clonal type A strains were isolated from 9 patients (in five cases from blood) during a 6-month period . The remaining K . pneumoniae strain harbored both the bla (SHV-11) + bla (CTX-M-14) genes and showed the clonal type C . A nosocomial outbreak by a SHV-5-producing multiresistant K . pneumoniae is reported in Spain in a neonatal-pediatric ICU ward . This is the first description of a K . pneumoniae harboring both the bla (SHV-11) and bla (CTX-M-14) genes in Spain.

Clin Microbiol Infect, 2005 Jan, 11(1), 31 - 8
Activity of cefepime and carbapenems in experimental pneumonia caused by porin-deficient Klebsiella pneumoniae producing FOX-5 beta-lactamase; Pichardo C et al.; The in-vivo activities of cefepime, imipenem and meropenem against the porin-deficient strain Klebsiella pneumoniae C2 and its derivative K . pneumoniae C2(pMG252) coding for the AmpC-type beta-lactamase FOX-5 were determined . Bactericidal activities were determined with the kill-curve method . A pneumonia model in guinea-pigs was developed, and C(max), t((1/2)) and DeltaT/MIC were calculated for the three agents tested . Animals were treated for 72 h with sterile saline (control group) or with cefepime, imipenem or meropenem (240 mg/kg/day, intramuscularly, three times daily) . Bacterial counts in lungs (log(10) CFU/g tissue) were determined by serial dilution . MICs (mg/L) of cefepime, imipenem and meropenem against K . pneumoniae C2/K . pneumoniae C2(pMG252), determined by macrodilution, were: 0.5/4, 0.5/0.5 and 0.25/0.5, respectively . Bacterial counts in the lungs of animals infected with K . pneumoniae C2 and treated with antimicrobial agents were always lower than in the control group (cefepime, 4.4 +/- 0.5; imipenem, 4.6 +/- 0.4; meropenem, 4.7 +/- 0.5; control group, 5.6 +/- 0.8; p < 0.01) . No significant differences were observed among the groups receiving therapy (p > 0.05) . Bacterial lung clearance was higher in treated animals than in control animals following infection with K . pneumoniae C2(pMG252) (cefepime, 4.5 +/- 0.4; imipenem, 4.0 +/- 0.3; meropenem, 4.6 +/- 0.4; control group, 6.1 +/- 0.6; p < 0.01), with imipenem producing better clearance than either cefepime or meropenem (p < 0.05) . Thus, in the guinea-pig pneumonia model, cefepime, imipenem and meropenem were each effective against the porin-deficient K . pneumoniae strain C2 and its derivative expressing the plasmid-mediated AmpC type beta-lactamase FOX-5.

Res Microbiol, 2005 Jan-Feb, 156(1), 76 - 81
Isolation and characterization of a high H(2)-producing strain Klebsiella oxytoca HP1 from a hot spring; Minnan L et al.; A hydrogen-producing bacterial strain was newly isolated from a hot spring and identified as Klebsiella oxytoca HP1 by 16S rRNA gene sequence analysis and detection by BioMerieux Vitek . Important parameters, including substrates, starting pH of culture, temperature and oxygen concentration for batch ferment hydrogen production, were investigated . Among different sugars, glucose and sucrose were the preferred substrates for hydrogen production . The optimal starting pH of culture was about 7.0 . The activity was drastically reduced in a prolonged fermentation due to the accumulation of organic acids . Increasing temperatures (from 25 to 35 degrees C) improved the hydrogen production activity . K . oxytoca HP1 produced hydrogen under different concentrations (1-10%) of oxygen in the gas phase, indicating that it is highly resistant to oxygen inhibition . Under batch ferment conditions, the maximal hydrogen production activity, rate and yield were obtained as 9.6 mmol/g dw h, 87.5 ml/l h and 1.0 mol/mol glucose (conversion 16.7%), respectively . In continuous hydrogen production, the maximum activity, rate and yield were 15.2 mmol/g dw h, 350.0 ml/l h and 3.6 mol/mol sucrose (conversion 32.5%), respectively . These results indicate that K . oxytoca HP1 is an ideal hydrogen producer.

J Clin Microbiol, 2005 Jan, 43(1), 516 - 9
First isolation of metallo-beta-lactamase-producing multiresistant Klebsiella pneumoniae from a patient in Brazil; Lincopan N et al.; A multiresistant Klebsiella pneumoniae isolate was taken from the blood of a 75-year-old patient with nosocomial pneumonia who developed septic shock and failed therapy with imipenem . The isolate presented an MIC of imipenem of 128 microg/ml, and the production of a metallo-beta-lactamase was confirmed by phenotypic and genotypic techniques . We here report, for the first time, the detection of a metalloenzyme (IMP-1)-producing K . pneumoniae clinical strain in Latin America . The gene responsible for this phenotype was found to be bla(IMP-1), carried in a class 1 integron.

J Clin Microbiol, 2005 Jan, 43(1), 494 - 6
Discrepancies and interpretation problems in susceptibility testing of VIM-1-producing Klebsiella pneumoniae isolates; Giakkoupi P et al.; Susceptibilities to beta-lactam antibiotics of five VIM-1-producing Klebsiella pneumoniae isolates were determined by broth microdilution, Etest, disk diffusion, and the automated systems Vitek 2, Phoenix, and MicroScan . Significant discrepancies were observed in the determination of susceptibility to imipenem and meropenem . Interpretation problems by the automated systems were also noted.

Rev Med Chil, 2004 Oct, 132(10), 1173 - 8
{Resistance to gentamicin, amikacin and ciprofloxacin among nosocomial isolates of klebsiella pneumoniae subspecie pneumoniae producing extended spectrum beta-lactamases}; Diaz PQ et al.; BACKGROUND: Klebsiella pneumoniae is a pathogenic bacterium frequently isolated from nosocomial samples, specially the subspecie pneunonlae, with extensive antibiolic resistance profiles, including third generation cepbhalosporiis, aminoglycosides and quinolones . This is specially true for those strains producing extended spectrum beta lactamases (ESBL) . AIM: To investigate the susceptibility to gentamicin, amikacin and ciprofloxacin and the presence of some aminogloycoside modifying enzyme (AMEs) among nosocomial strains of K pneumoniae subspecie pneumoniae producing ESBL . MATERIAL AND METHODS: The antibiotic resistant patterns and the level of resistance (minimal inhibitory concentration, MIC) of 100 strains, isoklted from sel ,eal bospitals of dcifferent Chilean cities, were deterl,in,ed . Tbe presence of some aminoglycosides modifying enzyme (AMEs) was investigated by PCR . RESULTS: Sixty five percent of strains were resistant to gentamicin, 47% were resistant to amikacin, and 29% were resistant to ciprofloxacin . The most frequent AMEs genes detected were the aac(6')-Ib gene (6'N-Acetyltransferase type Ib enzyme) in 69% of strains, conferring resistance to amikacin, kanamycin, tobramycin, and nieoniycin, and the gene aac(3)-IIa (3-Acetyltransferase type 3-IIa enzyme), in 36% of strains, conferring resistance to gentamlicin . CONCLUSIONS: Among nosocomial strains of K pneumoniae subspecie pneumoniae isolaterd from Chilean hospitals, there is an association between the production of ESBL and the resistance to others antimicrobial agents, especially aminoglycosides . Nevertheless, 71% of isolates are susceptible to ciprofloxacin.

Appl Microbiol Biotechnol . 2005 Jan 4; {Epub ahead of print}
Application of cyanide hydrolase from Klebsiella sp . in a biosensor system for the detection of low-level cyanide; Mak KK et al.; A partially purified preparation of cyanide hydrolase (cyanidase) from a bacterium, Klebsiella sp., was applied as a biocatalyst in a biosensor system for low-level cyanide detection . In the biosensor system cyanide hydrolase converts cyanide into formate and ammonia . The formate produced in the cyanide degradation was detected with a formate biosensor, in which formate dehydrogenase (FDH; E.C . 1.2.1.2) was co-immobilized with salicylate hydroxylase (SHL; E.C . 1.14.13.1) on a Clark electrode . The principle of the formate sensor is that FDH converts formate into carbon dioxide using beta-nicotinamide adenine dinucleotide hydrate (NAD(+)) . The corresponding NADH produced is then oxidized to NAD(+) by SHL using salicylate and oxygen . The oxygen consumption is monitored with the Clark electrode . The optimum buffer pH and temperature for the enzymatic hydrolysis of potassium cyanide were studied . The preliminary experiments including the pretreatment of cyanide with cyanide hydrolase and then detection by the formate sensor gave a detection limit at 7.3 mumol l(-1) cyanide . The linear range of the calibration curve was between 30 mumol l(-1) and 300 mumol l(-1) cyanide.

Diagn Microbiol Infect Dis, 2005 Jan, 51(1), 1 - 7
Evolution and dissemination of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae: Epidemiology and molecular report from the SENTRY Antimicrobial Surveillance Program (1997-2003); Dipersio JR et al.; During 2001, occurrences of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae isolates were detected in a single medical center (Hospital A) from the SENTRY Antimicrobial Surveillance Program that became endemic in long-term acute care areas and in the intensive care unit in 2002-2003 . Between 2001 and 2003, 123 patients were infected or colonized with ESBL-positive K . pneumoniae . Resistance profiles were determined by reference broth microdilution methods, and automated ribotyping and pulsed-field gel electrophoresis (PFGE) were performed . The ESBL-positive K . pneumoniae isolates were resistant to aztreonam, ceftazidime, aminoglycosides, and trimethoprim/sulfamethoxazole and susceptible to ciprofloxacin and tetracycline . In 1997, 1998, and 2000, 9 ESBL-producing K . pneumoniae strains from 2 New York City hospitals shared the same antibiograms and ribotype (204.2) as the strains from Hospital A . PFGE patterns divided Hospital A isolates into 2 subtypes (A and A(1)) and 3 New York City strains were similar to the Hospital A isolates (A(2), A(3), and A(4)) . Isoelectric focusing studies of 1 New York City isolate (A(4)) revealed pIs at 5.4, 7.7, and 8.2 . PCR and sequencing results from 1 strain of each Hospital A and 1 New York PFGE pattern determined that TEM-1 and SHV-5 (ESBL) were present in all strains . In addition, 2 New York isolates from 1998 (A(3) and A(4)) also had an OXA-2 enzyme . ESBL-producing K . pneumoniae isolates with ribotype 204.2 from SENTRY Program sites have been recognized in New York only since 1997 and in Hospital A beginning in 2001 . The similarities of the antibiogram and epidemiological patterns suggest that these isolates have persisted over time and may have evolved into different but genetically related endemic ESBL-positive K . pneumoniae clones that have the ability to cause sustained epidemic outbreaks in US medical centers.

Salud Publica Mex, 2004 Nov-Dec, 46(6), 524 - 8
{Characterization of SHV-5 beta-lactamase-producing Klebsiella pneumoniae in an intensive care unit}; Andrade V et al.; OBJECTIVE: To perform the molecular characterization of Klebsiella pneumoniae isolates from pediatric patients and health care workers at the intensive care unit of a tertiary care hospital in Mexico City . MATERIAL AND METHODS: Fifteen Klebsiella pneumoniae isolates collected during an outbreak in June 1996 were analyzed; eight were from patients and seven from health care workers of Mexico's Children's Hospital . Characterization of isolates was carried out by pulsed field gel electrophoresis (PFGE), random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) and serotyping, beta-Lactamase isoelectric focusing (IEF), and nucleotide sequencing of PCR products . RESULTS: Serotype 61 was predominant and correlated with genomic fingerprints of RAPD and PFGE in 11 of 15 isolates . One SHV-5-producer predominant clone with a high case-fatality rate was identified . CONCLUSIONS: Molecular biology techniques are useful tools to characterize the K . pneumoniae clone isolated from patients and health care workers, suggesting potential cross-transmission . These data call for strengthening control programs to prevent dissemination of nosocomial infections in the studied hospital.

Infect Immun, 2005 Jan, 73(1), 532 - 45
Central role of toll-like receptor 4 signaling and host defense in experimental pneumonia caused by Gram-negative bacteria; Schurr JR et al.; Toll-like receptor 4 (TLR4) has been identified as a receptor for lipopolysaccharide . However, the precise role of TLR4 in regulating gene expression in response to an infection caused by gram-negative bacteria has not been fully elucidated . The role of TLR4 signaling in coordinating gene expression was assessed by gene expression profiling in lung tissue in a mouse model of experimental pneumonia with a low-dose infection of Klebsiella pneumoniae . We analyzed four mouse strains: C57BL/6 mice, which are resistant to bacterial dissemination; 129/SvJ mice, which are susceptible; C3H/HeJ mice, which are susceptible and have defective TLR4 signaling; and their respective control strain, C3H/HeN (intermediate resistance) . At 4 h after infection, C57BL/6 and C3H/HeN mice demonstrated the greatest number of genes, with 67 shared induced genes which were TLR4 dependent and highly associated with the resistance phenotype . These genes included cytokine and chemokine genes required for neutrophil activation or recruitment, growth factor receptors, MyD88 (a critical adaptor protein for TLR signaling), and adhesion molecules . TLR4 signaling accounted for over 74% of the gene expression in the C3H background . These data suggest that early TLR4 signaling controls the vast majority of gene expression in the lung in response to an infection caused by gram-negative bacteria and that this subsequent gene expression determines survival of the host.

Antimicrob Agents Chemother, 2005 Jan, 49(1), 276 - 80
Pharmacodynamic profile of ertapenem against Klebsiella pneumoniae and Escherichia coli in a murine thigh model; Maglio D et al.; The pharmacodynamic profile of ertapenem was evaluated in a neutropenic mouse thigh infection model . Extended-spectrum beta-lactamase (ESBL)-positive and ESBL-negative clinical strains of Escherichia coli and Klebsiella pneumoniae were studied . MICs ranged from 0.0078 to 0.06 microg/ml with standard inoculum tests . Ertapenem doses were administered once to five times daily to achieve various exposures, reported as the percentage of the dosing interval that the concentration of free ertapenem was in excess of the MIC (%T>MIC(free)) . Mean values for the static exposure and 80% maximally effective exposure (ED(80)) were 19% (range, 2 to 38%) and 33% (range, 13 to 65%) T>MIC(free), respectively . Differences in exposure requirements based on the presence of an ESBL resistance mechanism or bacterial species were not evident . In addition, experiments using a 100-fold higher inoculum did not decrease the magnitude of the reduction in bacterial density from baseline achieved compared to lower-inoculum studies . The pharmacodynamic parameter of %T>MIC(free) correlated well with bactericidal activity for all isolates, and the static and ED(80) exposures are consistent with those reported previously for carbapenems.

Antimicrob Agents Chemother, 2005 Jan, 49(1), 256 - 63
bla(SHV) Genes in Klebsiella pneumoniae: different allele distributions are associated with different promoters within individual isolates; Hammond DS et al.; Extended-spectrum beta-lactamases (ESBLs) emerge by point mutation from non-extended-spectrum precursors . The aims of this study were to reveal the basis for variations in resistance levels found in a collection of 21 Klebsiella pneumoniae clinical isolates from Brisbane, Australia . Previous studies have shown that 20 of these isolates possess bla(SHV-11), bla(SHV-2a), and/or bla(SHV-12), and there is an association between the copy numbers of the ESBL-encoding genes and resistance levels . In this study, a real-time PCR method for interrogating the polymorphic sites at codons 238 and 240 was developed, and this confirmed the relationship between mutant gene copy numbers and resistance levels . The bla(SHV) promoter region was cloned from one of the ESBL-expressing isolates, and this showed that bla(SHV) genes exist downstream of two different promoters within this single isolate . These promoters have both been reported previously, and they differ by virtue of the presence or absence of an IS26 insertion . The bla(SHV) copy numbers in cis with the different promoters were measured, and the copy number of the IS26 promoter was correlated with resistance levels . Cloning and analysis of PCR products showed that different bla(SHV) variants existed in cis with individual promoters in individual isolates but that mutant genes were more abundant downstream of the IS26 promoter . There were no ESBL-positive isolates without this promoter . It was concluded that bla(SHV) in cis with the IS26 promoter is located on an amplifiable replicon, and the presence of the IS26 insertion may facilitate the acquisition of an ESBL-positive phenotype.

Acta Pharm, 2004 Sep, 54(3), 231 - 42
Preparation and evaluation of a new erythromycin derivative -- erythromycin taurate; Manna PK et al.; Erythromycin taurate, a new derivative of erythromycin, was prepared by reacting erythromycin base with tauric acid and its physico-chemical and biological properties were evaluated . The derivative has reasonably good solubility in organic solvents . The partition coefficient values in chloroform/water 1.17 and octanol/water 1.16 systems indicate its good distribution in various tissues in vivo . The in vitro antimicrobial potency of the derivative (833.33 microg mg(-1)) is higher than that of the existing derivatives such as erythromycin estolate, erythromycin stearate, erythromycin ethyl succinate, erythromycin gluceptate, erythromycin lactobionate . The antimicrobial spectrum is comparable to that of the parent compound . Our results indicate that erythromycin taurate has a high potential for possible clinical application and is more efficient against Escherichia coli and Klebsiella pneumoniae than the parent base.

Beijing Da Xue Xue Bao, 2004 Dec, 36(6), 637 - 41
{Genotype of extended-spectrum beta-lactamases produced by antibiotic-resistant Escherichia coli and Klebsiella pneumoniae in surgical intensive care unit.}; Wang PY et al.; OBJECTIVE:To describe the antibiotic resistant mode of extended-spectrum beta-lactamases(ESBLs) producing Escherichia coli (E . coli.) and Klebsiella pneumoniae (KPn) in surgical intensive care unit(SICU), and to implore the molecular epidemiology of ESBLs coding genes of these strains . METHODS: The minimal inhibitory concentrations (MICs) at antibiotics were examined by agar dilution method . The ESBLs coding genes were amplified by TEM, SHV and CTX-M specific primers . Amplicons of such genes with conjugates' plasmids as templates were sequenced . RESULTS: In vitro susceptibility tests of ESBLs producing strains showed a high level of resistance to most of the beta-lactam biotics, especially cefotaxime . 93.5% of these ESBLs positive strains contained CTX-M group genes,and 38.7% of the strains contained SHV genes . By sequencing, some genotype were determined: TEM-1, CTX-M-1,3,14,22 . CONCLUSION: ESBLs producing strains were resistant to most of the beta-lactam biotics . The most prevalent ESBLs genotype of ESBLs produced by E coli and KPn in SICU was CTX-M subgroup . The most probable reason might be the extensive use of cefotaxime.

Protein Expr Purif, 2005 Jan, 39(1), 107 - 15
Purification and characterization of the recombinant arylsulfatase cloned from Pseudoalteromonas carrageenovora; Kim DE et al.; Arylsulfatase cloned from a marine aerobic Gram-negative bacterium, Pseudoalteromonas carrageenovora, was overexpressed in Escherichia coli with 10muM IPTG induction . The expressed recombinant arylsulfatase was purified to homogeneity from the harvested cells through osmotic disruption and column chromatography methods, such as DEAE-cellulose anion exchange chromatography and Heparin-Sepharose affinity chromatography . The purified arylsulfatase was kinetically characterized using the synthetic substrate of phenolic ester, p-nitrophenyl sulfate (pNPS) . One unit of arylsulfatase catalyzes the liberation of 1.0mumol p-nitrophenol from pNPS per minute . The purified enzyme has a specific activity of 468 U/mg with a purification yield of 27% from the cell lysate, and exhibited an estimated molecular mass of 33kDa in SDS-PAGE analysis . The precursor polypeptide of 36kDa was processed by releasing a putative signal peptide, and the mature arylsulfatase of 33.1kDa with a N-terminal sequence of S-E-T-K-N was trafficked to periplasmic space . The enzyme had optimum reaction conditions for activity at pH 7.0 and at a temperature range of 40-45 degrees C . The apparent K(M) and k(cat) of the enzyme for hydrolysis of pNPS at pH 7.0 and at 45 degrees C were determined to be 1.15mM and 1000s(-1), respectively . Based on inhibitor studies along with optimal pH values and preferential periplasmic location of the enzyme, we suggest that the recombinant arylsulfatase from P . carrageenovora is probably similar to the Klebsiella sulfatase with serine residue in the active site.

Am J Respir Crit Care Med . 2004 Dec 10; {Epub ahead of print}
A Role for Hydroxy-Methylglutaryl Coenzyme A Reductase in Pulmonary Inflammation and Host Defense; Fessler MB et al.; Rationale: A growing literature indicates that hydroxy-methylglutaryl coenzyme A reductase inhibitors ('statins') modulate pro-inflammatory cellular signaling and functions . No studies to date, however, have addressed whether statins modulate pulmonary inflammation triggered by aerogenic stimuli, nor whether they affect host defense . Objectives: To test whether lovastatin modulates lipopolysaccharide-induced pulmonary inflammation and anti-bacterial host defense . Methods: In order to address these questions, and to confirm any effect of statins as dependent upon inhibition of hydroxy-methylglutaryl coenzyme A reductase, we treated C57Bl/6 mice with three oral doses of 10 mg/kg lovastatin (or vehicle) and three intraperitoneal doses of 10 mg/kg mevalonic acid (or saline), and then exposed them to: 1) aerosolized lipopolysaccharide; 2) intratracheal CXC chemokine KC; or 3) intratracheal Klebsiella pneumoniae . Measurements and Main Results: Lipopolysaccharide- and KC-induced airspace neutrophils were reduced by lovastatin, an effect that was blocked by mevalonic acid co-treatment . Lovastatin was also associated with reduced parenchymal myeloperoxidase and microvascular permeability, and altered airspace and serum cytokines following lipopolysaccharide . Native pulmonary clearance of K . pneumoniae was inhibited by lovastatin, and extrapulmonary dissemination enhanced, both reversibly with mevalonic acid . Ex vivo studies of neutrophils isolated from lovastatin-treated mice confirmed inhibitory effects upon rac activation, actin polymerization, chemotaxis, and bacterial killing . Conclusions: Lovastatin attenuates pulmonary inflammation induced by aerosolized lipopolysaccharide, and impairs host defense.

J Med Microbiol, 2005 Jan, 54(1), 7 - 13
Compensatory response of IL-1 gene knockout mice after pulmonary infection with Klebsiella pneumoniae; Tanabe M et al.; This study was designed to determine the role of interleukin (IL)-1 in the inflammatory response against experimentally induced pneumonia caused by Klebsiella pneumoniae . The host immune responses of IL-1 gene knockout (IL-1 KO) mice and immunocompetent wild-type (WT) mice were compared after pulmonary infection with K . pneumoniae . There were no significant differences between the survival rates and viable bacterial counts in lungs and blood of IL-1 KO and WT mice after pulmonary infections under different conditions . Histopathological analysis showed a similar inflammatory response in both groups of mice . However, in the early stage of infection, the level of tumour necrosis factor alpha (TNF-alpha) in homogenized lungs of IL-1 KO mice was significantly higher than in WT mice . To determine the role of endogenous TNF-alpha in the recovery of the defence mechanism in IL-1 KO mice, mice were treated with an anti-TNF-alpha mAb before infection with K . pneumoniae . The results revealed a significantly lower survival rate of anti-TNF-alpha mAb-treated IL-1 KO mice than BSA-treated IL-1 KO mice . The data suggest that compensatory production of TNF-alpha in IL-1 KO mice contributes to the host defence against K . pneumoniae infection.

Acta Crystallogr D Biol Crystallogr, 2004 Dec, 60(Pt 12 Pt 2), 2352 - 4 Epub 2004 Dec.
Expression, crystallization and preliminary X-ray crystallographic studies of Klebsiella pneumoniae maltohexaose-producing alpha-amylase; Momma M et al.; A recombinant form of Klebsiella pneumoniae maltohexaose-producing alpha-amylase has been overexpressed in Escherichia coli and purified to homogeneity . Crystals were obtained at 293 K by the microbatch technique using 80 mM sodium/potassium phosphate buffer pH 6.2 containing 8% polyethylene glycol 3000, 4% polyethylene glycol 3350 and 40 mM sodium thiocyanate . Crystals of the overexpressed recombinant enzyme diffracted to better than 2.5 A resolution at 95 K using a synchrotron-radiation source . The crystals belong to the primitive monoclinic space group P2(1), with unit-cell parameters a = 74.8, b = 107.6, c = 82.2 A, beta = 96.2 degrees . Assuming the presence of two molecules per asymmetric unit, the V(M) value for the crystal was 2.3 A(3) Da(-1), indicating a solvent content of 47%.

J Clin Microbiol, 2004 Dec, 42(12), 5715 - 21
Phenotypic and molecular detection of CTX-M-beta-lactamases produced by Escherichia coli and Klebsiella spp; Pitout JD et al.; Organisms producing CTX-M-beta-lactamases are emerging around the world as a source of resistance to oxyiminocephalosporins such as cefotaxime (CTX) . However, the laboratory detection of these strains is not well defined . In this study, a molecular detection assay for the identification of CTX-M-beta-lactamase genes was developed and used to investigate the prevalence of these enzymes among clinical isolates of Escherichia coli and Klebsiella species in the Calgary Health Region during 2000 to 2002 . In addition, National Committee for Clinical Laboratory Standards (NCCLS) recommendations were evaluated for the ability to detect isolates with CTX-M extended-spectrum beta-lactamases (ESBLs) . The PCR assay consisted of four primer sets and demonstrated 100% specificity and sensitivity for detecting different groups of CTX-M-beta-lactamases in control strains producing well-characterized ESBLs . Using these primer sets, 175 clinical strains producing ESBLs were examined for the presence of CTX-M enzymes; 24 (14%) were positive for bla(CTX-M-1-like) genes, 95 (54%) were positive for bla(CTX-M-14-like) genes, and the remaining 56 (32%) were negative for bla(CTX-M) genes . Following the NCCLS recommendations for ESBL testing, all of the control and clinical strains were detected when screened with cefpodoxime and when both cefotaxime and ceftazidime with clavulanate were used as confirmation tests.

Clin Infect Dis, 2004 Dec 1, 39(11), 1654 - 9 Epub 2004 Dec 1.
Pyogenic liver abscess: recent trends in etiology and mortality; Rahimian J et al.; BACKGROUND: Pyogenic liver abscess, a potentially life-threatening disease, has undergone significant changes in epidemiology, management, and mortality over the past several decades . METHODS: We reviewed the data for patients admitted to Bellevue Hospital and New York University Downtown Hospital (New York, New York) over a 10-year period . RESULTS: Of 79 cases reviewed, 43% occurred in patients with underlying biliary disease . The most common symptoms were fever, chills, and right upper quadrant pain or tenderness . The most common laboratory abnormalities were an elevated white blood cell count (in 68% of cases), temperature >or=38.1 degrees C (90%), a low albumin level (70.2%), and an elevated alkaline phosphatase level (67%) . Seventy percent of the abscesses were in the right lobe, and 77% were solitary . Klebsiella pneumoniae was identified in 41% of cases in which a pathogen was recovered . Eighteen (50%) of 36 Asian patients had K . pneumoniae isolated, in contrast to 6 (27.3%) of 22 non-Asian patients (not statistically significant) . Fifty-six percent of cases involved treatment with percutaneous drainage . Although prior reports noted mortality of 11%-31%, we observed only 2 deaths (mortality, 2.5%) . CONCLUSIONS: The data suggest that K . pneumoniae has become the predominant etiology of pyogenic liver abscess and that mortality from this disease has decreased substantially.

Antimicrob Agents Chemother, 2004 Dec, 48(12), 4829 - 34
Molecular and kinetic comparison of the novel extended-spectrum beta-lactamases CTX-M-25 and CTX-M-26; Munday CJ et al.; CTX-M-25 is a novel extended-spectrum beta-lactamase isolated from a single Canadian Escherichia coli isolate . Susceptibility testing demonstrated that this enzyme confers resistance to both cefotaxime and ceftazidime, but the level of resistance was reduced with the addition of beta-lactamase inhibitors . The bla(CTX-M-25) gene was detected on a 111-kb plasmid . It is a member of the CTX-M-8 group and has the closest amino acid identity (99%; three amino acid substitutions) with CTX-M-26 . The bla(CTX-M-26) gene was detected on a 100-kb plasmid isolated from a Klebsiella pneumoniae strain from the United Kingdom, and plasmid profiling revealed that it showed some homology to the bla(CTX-M-25)-harboring plasmid . Both CTX-M genes were located downstream of ISEcp1, although the copy upstream of bla(CTX-M-25) was disrupted by IS50-A . Comparative kinetic studies of recombinant CTX-M-25 and CTX-M-26 enzymes showed that CTX-M-25 has a higher level of ceftazidime hydrolysis (kcat values, 33 and 0.005 s(-1) for CTX-M-25 and CTX-M-26, respectively).

Antimicrob Agents Chemother, 2004 Dec, 48(12), 4574 - 81
Bloodstream infections due to extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae: risk factors for mortality and treatment outcome, with special emphasis on antimicrobial therapy; Kang CI et al.; This study was conducted to evaluate risk factors for mortality and treatment outcome of bloodstream infections due to extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae (ESBL-EK) . ESBL production in stored K . pneumoniae and E . coli blood isolates from Jan 1998 to Dec 2002 was phenotypically determined according to NCCLS guidelines and/or the double-disk synergy test . A total of 133 patients with ESBL-EK bacteremia, including 66 patients with ESBL-producing K . pneumoniae and 67 with ESBL-producing E . coli, were enrolled . The overall 30-day mortality rate was 25.6% (34 of 133) . Independent risk factors for mortality were severe sepsis, peritonitis, neutropenia, increasing Acute Physiology and Chronic Health Evaluation II score, and administration of broad-spectrum cephalosporin as definitive antimicrobial therapy (P < 0.05 for each of these risk factors) . In 117 of the 133 patients, excluding 16 patients who died within 3 days after blood culture sample acquisition, the 30-day mortality rates according to definitive antibiotics were as follows: carbapenem, 12.9% (8 of 62); ciprofloxacin, 10.3% (3 of 29); and others, such as cephalosporin or an aminoglycoside, 26.9% (7 of 26) . When patients who received appropriate definitive antibiotics, such as carbapenem or ciprofloxacin, were evaluated, mortality in patients receiving inappropriate empirical antimicrobial therapy was found not to be significantly higher than mortality in those receiving appropriate empirical antimicrobial therapy (18.9 versus 15.5%; P = 0.666) . Carbapenem and ciprofloxacin were the most effective antibiotics in antimicrobial therapy for ESBL-EK bacteremia . A delay in appropriate definitive antimicrobial therapy was not associated with higher mortality if antimicrobial therapy was adjusted appropriately according to the susceptibility results . Our data suggest that more prudent use of carbapenem as empirical antibiotic may be reasonable.

Am J Kidney Dis, 2004 Dec, 44(6), e102 - 6
Expanded-spectrum beta-lactamase producing Klebsiella pneumoniae-related peritonitis in a patient on peritoneal dialysis; Yang CC et al.; While hospitalized for pneumonia with ventilator-dependent respiratory failure, a 45-year-old man on continuous ambulatory peritoneal dialysis (CAPD) had nosocomial peritonitis secondary to infection by expanded spectrum beta-lactamase producing Klebsiella pneumoniae (ESBL-Kp) . He was treated successfully with a 3-week course of intraperitoneal (IP) flomoxef therapy without subsequent relapse, loss of peritoneal catheter, ultrafiltration failure, or dialysis inadequacy . The International Consensus Panel recommends IP ceftazidime as the treatment of choice for CAPD patients suffering Klebsiella species-related peritonitis . However, the most appropriate form of IP antibiotic therapy and the outcomes for expanded-spectrum beta-lactamase (ESBL)-producing bacteria-related peritonitis for CAPD patients have not been established yet . Further, the ability to correctly report minimal inhibitory concentrations (MICs) of ceftazidime for ESBL bacteria in the resistant range varies between laboratories, making the diagnosis of ESBL-Kp-related CAPD peritonitis more complex and difficult . Thus, it appears reasonable to suggest that its incidence is probably underestimated and its significance ignored . The authors suggest that a 3-week IP treatment with flomoxef, a synthesized oxacephem, with loading and maintenance doses of 250 and 125 mg/L, respectively, is effective and safe for ESBL-Kp-related peritonitis in these patients . ESBL producing bacterial infection should be considered as a possible cause of overt CAPD-related peritonitis . Early detection of ESBLB pathogens and institution of effective antibiotic treatment may improve the prognosis.

Infect Immun, 2004 Dec, 72(12), 7107 - 14
Capsule polysaccharide mediates bacterial resistance to antimicrobial peptides; Campos MA et al.; The innate immune system plays a critical role in the defense of areas exposed to microorganisms . There is an increasing body of evidence indicating that antimicrobial peptides and proteins (APs) are one of the most important weapons of this system and that they make up the protective front for the respiratory tract . On the other hand, it is known that pathogenic organisms have developed countermeasures to resist these agents such as reducing the net negative charge of the bacterial membranes . Here we report the characterization of a novel mechanism of resistance to APs that is dependent on the bacterial capsule polysaccharide (CPS) . Klebsiella pneumoniae CPS mutant was more sensitive than the wild type to human neutrophil defensin 1, beta-defensin 1, lactoferrin, protamine sulfate, and polymyxin B . K . pneumoniae lipopolysaccharide O antigen did not play an important role in AP resistance, and CPS was the only factor conferring protection against polymyxin B in strains lacking O antigen . In addition, we found a significant correlation between the amount of CPS expressed by a given strain and the resistance to polymyxin B . We also showed that K . pneumoniae CPS mutant bound more polymyxin B than the wild-type strain with a concomitant increased in the self-promoted pathway . Taken together, our results suggest that CPS protects bacteria by limiting the interaction of APs with the surface . Finally, we report that K . pneumoniae increased the amount of CPS and upregulated cps transcription when grown in the presence of polymyxin B and lactoferrin.

Biomedica, 2004 Sep, 24(3), 252 - 61
{Molecular epidemiology of nosocomial infection by extended-spectrum beta-lactamases-producing Klebsiella pneumoniae}; Espinal PA et al.; Molecular epidemiology applied to the study of nosocomial infection has been fundamental in formulating and evaluating control methods . From patients in a level 3 Bogota hospital, Klebsiella pneumoniae samples were isolated that produced extended-spectrum beta-lactamases (ESBL) . Each of 15 isolates was characterized microbiologically and by molecular characters realized by pulsed field gel electrophoresis (PFGE) and by repetitive-DNA sequences amplification (REP-PCR) . Antimicrobial susceptibility and ESBL production was determined in accordance with NCCLS guidelines . The beta-lactamases were evaluated by isoelectric-focusing and PCR . Twelve (80%) of the isolates were associated with nosocomial infection; 11 of them were from intensive care units . The antibiotic susceptibility displayed 13 resistance patterns--87% presented co-resistance to amikacin, 53% to gentamicin, 33% to ciprofloxacin, 40% to cefepime, 67% to piperacillin/tazobactam, 60% to trimethoprim/sulfamethoxazole and 47% to chloranphenicol . All were sensitive to imipenem . Production of TEM and SHV beta-lactamases was detected simultaneously in most isolates by isoelectric focusing and 93.3% produced a ceftazidimase of pl 8.2 of the SHV-5 type . The 15 isolates were grouped into 11 and 12 electrophoretic patterns by PFGE and REP-PCR, respectively . The degree of genetic variability indicated an endogenous origin of the nosocomial infections.

Int J Syst Evol Microbiol, 2004 Nov, 54(Pt 6), 2131 - 6
Klebsiella singaporensis sp . nov., a novel isomaltulose-producing bacterium; Li X et al.; Cells of strain LX3(T), isolated from soil, were Gram-negative, facultatively anaerobic, non-motile, capsulated and non-endospore-forming straight rods, able to grow at 10 degrees C, unable to produce gas from lactose at 45 degrees C and unable to produce indole . The isolate converted sucrose to isomaltulose and did not produce detectable glucose by-products . The G+C content of the DNA was 56.4 mol% . Furthermore, comparison of 16S rRNA and rpoB gene sequences showed that the isolate clearly belongs to the genus Klebsiella . The closest phylogenetic relative was Klebsiella pneumoniae, there being 99.3 and 97.5 % similarity in 16S rRNA and rpoB gene sequences, respectively . DNA-DNA hybridization analysis demonstrated a very low level of relatedness to other members of the genus Klebsiella, indicating that the isolated strain and other species in the genus Klebsiella were not related at the species level . The isolate could be differentiated from other previously described members of the genus Klebsiella on the basis of phenotypic differences and 16S rRNA and rpoB gene sequence divergence, together with DNA-DNA reassociation data . Therefore, it is proposed that strain LX3(T) (=DSM 16265(T)=JCM 12419(T)) should be classified as the type strain of a novel species of genus Klebsiella, Klebsiella singaporensis sp . nov.

Med Dosw Mikrobiol, 2004, 56(2), 161 - 71
{Detection of expression of extended-spectrum beta-lactamases (ESBL) in clinical strains of Klebsiella pneumoniae and Escherichia coli; comparison of E-test and two disc methods}; Andrzejewska E et al.; The aim of this study was to compare the effectiveness of E-test and two disc methods applied for the detection of extended spectrum beta-lactamases . All strains were tested by E-test, by double-disc synergy test (DDST) according to Jarlier (cefotaxim, ceftazidim, aztreonam and clavulanic acid) and also by disc test according to Appleton (cefpodoxime and cefpodoxime with clavulanic acid, CPD and CD01 disc) . We tested 148 clinical strains of E . coli and 78 strains of K . Pneumoniae . In case of K . pneumoniae, the activity of the ESBLs was detected among 30 strains--both in E-test, Jarlier test and Appleton test . Among E . coli, four strains were found ESBL-positive in the test according to Jarlier but only three strain of these when E-test and Appleton test was used . The results of investigations performed suggest, that E-test and disc methods according both Jarlier and Appleton have the same effectiveness in detection ESBLs among K . pneumoniae strains . However, in case of E . coli, interpretation of results may present a problem.

J Clin Microbiol, 2004 Nov, 42(11), 5337 - 40
Complexity of Klebsiella pneumoniae isolates resistant to both cephamycins and extended-spectrum cephalosporins at a teaching hospital in Taiwan; Yan JJ et al.; Among 99 clinical Klebsiella pneumoniae isolates resistant to cefoxitin and extended-spectrum cephalosporins, coexistence of AmpC (DHA-1, CMY-2, or CMY-8) and extended-spectrum beta-lactamases (CTX-M and/or SHV) was detected in a total of 35 . The remainder produced AmpC (n = 42), extended-spectrum beta-lactamases (n = 9), metallo-beta-lactamases (n = 2), or none of these enzymes (n = 11) . Phenotypic characteristics of these isolates were demonstrated.

Appl Microbiol Biotechnol, 2005 Feb, 66(5), 589 - 96 Epub 2004 Nov 04.
Klebsiella planticola strain DSZ mineralizes simazine: physiological adaptations involved in the process; Sanchez M et al.; We examined the ability of a soil bacterium, Klebsiella planticola strain DSZ, to degrade the herbicide simazine (SZ) . Strain DSZ is metabolically diverse and grows on a wide range of s-triazine and aromatic compounds . DSZ cells grown in liquid medium with SZ (in 10 mM ethanol) as carbon source mineralized 71.6+/-1.3% of 0.025 mM SZ with a yield of 4.6+/-0.3 mug cell dry weight mmol(-1) carbon . The metabolites produced by DSZ during SZ degradation included ammeline, cyanuric acid, N-formylurea and urea . We studied the physiological adaptations which allow strain DSZ to metabolize SZ . Using scanning electron microscopy, we detected DSZ cells covering the surfaces of SZ crystals when the herbicide was used at high concentrations (0.1 mM) . The membrane order observed by FTIR spectroscopy showed membrane activity at low temperature (4 degrees C) to assimilate the herbicide . Membrane fatty acid analysis demonstrated that strain DSZ adapted to grow on SZ by increasing the degree of saturation of membrane lipid fatty acid; and the opposite effect was detected when both SZ and ethanol were used as carbon sources . This confirms the modulator effect of ethanol on membrane fluidity.

Int J Antimicrob Agents, 2004 Nov, 24(5), 508 - 10
Prevalence of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae in an urban hospital in Dhaka, Bangladesh; Rahman MM et al.; The prevalence of extended-spectrum beta-lactamases (ESBL)-producing organisms in an urban hospital in Dhaka City was assessed over a 10-month period . A double disk test was performed to detect ESBL-producing Escherichia coli and Klebsiella pneumoniae . 43.2% and 39.5% of E . coli and K . pneumoniae had ESBL phenotypes, respectively . The combination of augmentin with ceftazidime detected the most ESBL-producing E . coli (39.5%) while augmentin with ceftriaxone was the best combination for the detection of ESBL (31.6%) in K . pneumoniae.

Immunobiology, 2004, 209(3), 277 - 82
Immunomodulating effects of cefodizime on Klebsiella pneumoniae-stimulated neutrophils; Song H et al.; To explore the immunoregulating effects of cefodizime on neutrophils and its mechanisms, we detected the expression of some cytokines secreted by neutrophils after heat-killed Klebsiella pneumoniae induced inflammation . We analyzed the changes of signal transduction in this process by detecting the mRNA expression of toll like receptor 4 (TLR4) and the inhibitor factor of kappaBalpha (I-kappaBalpha) expressed by neutrophils . The activity of nuclear factor kappaB (NF-kappaB) in neutrophils was also assayed by electrophoretic mobility shift assay (EMSA) . We found cefodizime increased neutrophil production of TNF-alpha, IL-1beta in the early stage of inflammation, which was in agreement with the enhanced mRNA expression of TLR4 and DNA-binding activity of NF-kappaB . Taken together, the immunomodulating effects of cefodizime on cytokine production of K . pneumoniae stimulated neutrophils is possibly due to its regulation of TLR4 mRNA expression and DNA binding activities of NF-kappaB through the LPS-TLR4-NF-kappaB pathway.

Infect Control Hosp Epidemiol, 2004 Oct, 25(10), 883 - 5
Intrinsic Klebsiella pneumoniae contamination of liquid germicidal hand soap containing chlorhexidine; Brooks SE et al.; We describe intrinsic contamination with Klebsiella pneumoniae occurring during the manufacture of germicidal hand soap, labeled as containing 2% chlorhexidine, used throughout a 350-bed community medical center . A 3-year retrospective study failed to find evidence of increased incidence of clinical isolates of this strain.

Infect Control Hosp Epidemiol, 2004 Oct, 25(10), 878 - 82
A cluster of nosocomial Klebsiella oxytoca bloodstream infections in a university hospital; Sardan YC et al.; BACKGROUND: On February 19, 2003, four patients (patients 1-4) in the neurology ward underwent cranial magnetic resonance angiography (MRA) and developed fever within 1 hour afterward . Klebsiella oxytoca was isolated from blood cultures of patients 1 through 3 . OBJECTIVE: To identify the source of this cluster of nosocomial K . oxytoca bloodstream infections . DESIGN: Outbreak investigation . SETTING: A 1,000-bed university hospital . METHODS: The infection control team reviewed patient charts and interviewed nursing staff about the preparation and administration of parenteral fluids . The procedure of cranial MRA was observed . Arbitrarily primed polymerase chain reaction (AP-PCR) was performed to show the clonal relationship among these three strains . RESULTS: AP-PCR revealed that three K . oxytoca isolates had the same molecular profile . Cranial MRA was found to be the only common source among these patients . During MRA, before injection of the contrast medium, normal saline solution was infused to check the functioning of the intravenous catheter . Use of the solution for multiple patients was routine, but the access diaphragm of the bottle was not cleansed . The bottle of normal saline solution used on February 19 had already been discarded and the culture sample taken from the solution on the day of observation was sterile . CONCLUSIONS: We speculate that normal saline solution became contaminated during manipulation and that successive uses might have been responsible for this cluster . Poor aseptic techniques employed during successive uses appear to be the most likely route of contamination . Use of parenteral solutions for multiple patients was discontinued.

Infect Control Hosp Epidemiol, 2004 Oct, 25(10), 832 - 7
Reduced use of third-generation cephalosporins decreases the acquisition of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae; Lee SO et al.; OBJECTIVES: To identify risk factors for the respiratory acquisition of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae among patients admitted to a neurosurgical intensive care unit (NSICU) and to modify them without changing general infection control measures . DESIGN: Nested case-control and intervention study . SETTING: A 1,200-bed, tertiary-care teaching hospital with a 17-bed NSICU . METHODS: Sputa of all patients admitted to the NSICU were cultured weekly during the study . From October 2002 through February 2003, 29 case-patients from whose sputum ESBL-producing K . pneumoniae was isolated were detected and 59 controls-patients were randomly selected among patients without any positive isolate of ESBL-producing K . pneumoniae . After analyzing the risk factors, we intervened to modify them and compared the acquisition rate of ESBL-producing K . pneumoniae before (October 2002 to February 2003) and after (April to August 2003) the intervention . RESULTS: Multivariate analysis showed that prior exposure to third-generation cephalosporins (TGCs) (OR, 6.0; CI95, 1.9 to 18.6; P = .002) was an independent risk factor of ESBL-producing K . pneumoniae acquisition . The neurosurgical team was notified of the result, and the infectious diseases specialist visited the NSICU three times a week to regulate TGC use during the intervention period . Patients admitted before the intervention were older than patients admitted after . The respiratory acquisition of ESBL-producing K . pneumoniae per 1,000 patient-days (13.5 {CI95, 8.9 to 18.1} vs 2.7 {CI95, 0.9 to 4.6}) and the antimicrobial use density of TGCs (38.2 +/- 5.0 vs 17.3 +/- 2.6; P < .001) decreased significantly after the intervention . CONCLUSION: Prior exposure to TGCs was an independent risk factor for the respiratory acquisition of ESBL-producing K . pneumoniae, and less use of TGCs was associated with a decrease in acquisition.

Infect Control Hosp Epidemiol, 2004 Oct, 25(10), 812 - 8
Surveillance in Taiwan using molecular epidemiology for extended-spectrum beta-lactamase-producing Klebsiella pneumoniae; Yu WL et al.; OBJECTIVE: To evaluate intrahospital and interhospital clonal dissemination of extended-spectrum beta-lactamase (ESBL)-producing strains of Klebsiella pneumoniae . SETTING: Eight tertiary-care university hospitals and 16 regional hospitals in Taiwan . METHODS: Two hundred eleven confirmed ESBL-producing isolates of K . pneumoniae were collected from January 1998 to June 2000 . The isolates were characterized by various typing methods, including antibiogram (9 antimicrobial agents), computer-based ribotyping, pulsed-field gel electrophoresis (PFGE), and isoelectric focusing of beta-lactamase . RESULTS: Ribotyping identified 70 distinct ribogroups among 200 isolates evaluated . Forty-three of these ribogroups were unique . Eleven ribogroups, comprising 115 isolates, were detected in more than one hospital (interhospital dissemination), whereas 16 groups (42 isolates) were detected in more than one patient within a hospital (intrahospital dissemination) . The combination of ribotyping and PFGE identified two large epidemic clones, which were called 691.5/PFGE-G and 595.7/PFGE-A . These epidemic clones were detected mainly in the hospitals located in the northern and central regions of Taiwan . However, variation of the profiles of antibiograms and isoelectric focusing was apparent within each clone . In addition, isolates with the same isoelectric focusing profile (isoelectric points 7.9, 8.2, and 8.4) and antibiogram (resistance to 9 compounds evaluated) were present among different molecular-typed clones . CONCLUSIONS: Our results showed that clonal dissemination (both interhospital and intrahospital dissemination) is occurring in several regions of Taiwan . Rapid computer-based ribotyping associated with PFGE demonstrated multiple epidemic clones of ESBL-producing K . pneumoniae in Taiwan . The combination of phenotypic and molecular methods has proved useful to characterize these epidemic clones.

Antimicrob Agents Chemother, 2004 Nov, 48(11), 4466 - 9
SHV-49, a novel inhibitor-resistant beta-lactamase in a clinical isolate of Klebsiella pneumoniae; Dubois V et al.; A clinical strain of Klebsiella pneumoniae carried the bla(SHV-49) gene, encoding a novel inhibitor-resistant beta-lactamase of pI 7.6, derived from SHV-1 by the single substitution M69I . It also harbored a gene differing from bla(SHV-11) by four silent mutations and coding for a penicillinase . Both genes were chromosome located and might represent either a species-specific gene or an acquired resistance gene.

Zhonghua Yi Xue Za Zhi, 2004 Sep 2, 84(17), 1454 - 9
{Identification and expression of blaCTX-M-14 and blaCTX-M-24}; Xiong ZZ et al.; OBJECTIVE: To identify the ESBL gene and the prevalence in Escherichia coli and Klebsiella pneumoniae strain isolated from Huashan Hospital, Shanghai . METHODS: Isolates were confirmed as an ESBL producing strain by double-disk synergy test and NCCLS Confirmatory Test . Antibiotic susceptibilities were determined by standard agar dilution procedure on Mueller-Hinton agar . To determine whether the resistance was transferable, the conjugation experiment was performed; plasmids were isolated from clinical isolates and transcojugants . The partial bla(gene) of ESBL producing isolates and their transcojugants were detected by PCR using universal primers for TEM, SHV, CTX-M-1group, Toho-1group, CTX-M-13group respectively . The entire bla(CTX-M-13) group were amplified by PCR using the primers outside the Open Reading Frame (ORF) of CTX-M-13group beta-lactamases; the PCR products of entire bla(CTX-M-13)group were cloned into vector and the recombinant plasmids were transformed into the recipient strain for expression; the PCR products were also directly sequenced and analyzed; the clinical isolates of ESBL producers were detected by PFGE . RESULTS: ESBL producers were resistant to most beta-lactams and non-beta-lactams . Most transconjugants were obtained at frequency of 10(-4) approximately 10(-5) and resistance to non-beta-lactams was cotransferred with the ESBL activity to the transconjugant . A plasmid of about > 23.1 kb was obtained from each tansconjugant by plasmid extraction . Partial gene amplification products of CTX-M-13 group gene were obtained from isolates and their transconjugants . The bla(CTX-M-13)group from 4 transconjugants were identified as bla(CTX-M-14), and other six were bla(CTX-M-24); those ESBLs were mediated by plasmids (> 23.1 kb); the transformants producing CTX-M-14 or CTX-M-24 were resistant to most beta-lactams, which were much more resistant to cefotaxime than to ceftazidine; PFGE patterns of those isolates were different . CONCLUSION: clinical isolate of Escherichia coli and Klebsiella pneumoniae isolated from Huashan Hospital, Shanhai produced CTX-M-14 or CTX-M-24, which caused the isolate resistant to most beta-lactams; no clone spread in those isolates was found.

Mol Plant Microbe Interact, 2004 Oct, 17(10), 1078 - 85
Nitrogen fixation in wheat provided by Klebsiella pneumoniae 342; Iniguez AL et al.; In this report, all of the criteria necessary for the demonstration of nitrogen fixation in wheat (Triticum aestivum L.), the world's most important crop, are shown upon inoculation with a nitrogen-fixing bacterium, Klebsiella pneumoniae 342 (Kp342) . Kp342 relieved nitrogen (N) deficiency symptoms and increased total N and N concentration in the plant . Nitrogen fixation was confirmed by 15N isotope dilution in the plant tissue and in a plant product, chlorophyll . All of these observations were in contrast to uninoculated plants, plants inoculated with a nitrogen-fixing mutant of Kp342, and plants inoculated with dead Kp342 cells . Nitrogenase reductase was produced by Kp342 in the intercellular space of the root cortex . Wild-type Kp342 and the nifH mutant colonized the interior of wheat roots in equal numbers on a fresh weight basis . The nitrogen fixation phenotype described here was specific to cv . Trenton . Inoculation of cvs . Russ or Stoa with Kp342 resulted in no relief of nitrogen deficiency symptoms.

Mol Microbiol, 2004 Nov, 54(3), 647 - 64
Structure and assembly of the pseudopilin PulG; Kohler R et al.; The pseudopilin PulG is one of several essential components of the type II pullulanase secretion machinery (the Pul secreton) of the Gram-negative bacterium Klebsiella oxytoca . The sequence of the N-terminal 25 amino acids of the PulG precursor is hydrophobic and very similar to the corresponding region of type IV pilins . The structure of a truncated PulG (lacking the homologous region), as determined by X-ray crystallography, was found to include part of the long N-terminal alpha-helix and the four internal anti-parallel beta-strands that characterize type IV pilins, but PulG lacks the highly variable loop region with a disulphide bond that is found in the latter . When overproduced, PulG forms flexible pili whose structural features, as visualized by electron microscopy, are similar to those of bacterial type IV pili . The average helical repeat comprises 17 PulG subunits and four helical turns . Electron microscopy and molecular modelling show that PulG probably assembles into left-handed helical pili with the long N-terminal alpha-helix tightly packed in the centre of the pilus . As in the type IV pilins, the hydrophobic N-terminal part of the PulG alpha-helix is necessary for its assembly . Subtle sequence variations within this highly conserved segment seem to determine whether or not a type IV pilin can be assembled into pili by the Pul secreton.

Arch Microbiol, 2004 Nov, 182(5), 414 - 20
Oxaloacetate decarboxylase of Archaeoglobus fulgidus: cloning of genes and expression in Escherichia coli; Dahinden P et al.; Archaeoglobus fulgidus harbors three consecutive and one distantly located gene with similarity to the oxaloacetate decarboxylase Na+ pump of Klebsiella pneumoniae (KpOadGAB) . The water-soluble carboxyl transferase (AfOadA) and the biotin protein (AfOadC) were readily synthesized in Escherichia coli, but the membrane-bound subunits AfOadB and AfOadG were not . AfOadA was affinity purified from inclusion bodies after refolding and AfOadC was affinity purified from the cytosol . Isolated AfOadA catalyzed the carboxyl transfer from {4-14C}-oxaloacetate to the prosthetic biotin group of AfOadC or the corresponding biotin domain of KpOadA . Conversely, the carboxyl transferase domain of KpOadA exhibited catalytic activity not only with its pertinent biotin domain but also withAfOadC.

Am J Ophthalmol, 2004 Oct, 138(4), 662 - 3
Endophthalmitis caused by Klebsiella species; Scott IU et al.; PURPOSE: To investigate clinical settings, antibiotic sensitivities, and visual outcomes associated with endophthalmitis caused by Klebsiella species . DESIGN: Retrospective case series . METHODS: Record review of patients with endophthalmitis caused by Klebsiella (1984 through 2003) . RESULTS: Clinical settings included cataract surgery (one eye), trauma (two), perforated corneal ulcer (one), and endogenous associated with hepatic abscess (one) . Pretreatment vision was hand motions or better in four eyes (80%) . Initial treatment was enucleation (one eye), pars plana vitrectomy (two), and vitreous tap and injection (two); intravitreal antibiotics were administered to all nonenucleated eyes . Klebsiella was sensitive to one or more antibiotics administered initially in all cases . In nonenucleated eyes, final acuity was >or=20/400 in two, 1/200 in one, and light perception in one . CONCLUSION: Despite treatment with appropriate antibiotics, endophthalmitis caused by Klebsiella species is associated with generally poor visual outcomes.

Microbes Infect, 2004 Nov, 6(13), 1191 - 8
High prevalence of phagocytic-resistant capsular serotypes of Klebsiella pneumoniae in liver abscess; Lin JC et al.; To better understand the role of capsular polysaccharide (CPS) K1 or K2 in Klebsiella pneumoniae liver abscess as well as the development of metastasis to eye, neutrophil phagocytosis of 70 CPS isolates including K1 (n = 23)/K2 (n = 10), non-K1/K2 (n = 37) was evaluated by flow cytometry, fluorescence imaging, and electron microscopy . K1/K2 isolates were significantly more resistant to phagocytosis (P < 0.0001) than non-K1/K2 isolates and displayed increased resistance to intracellular killing . Although mucoid phenotype (M-type) K1/K2 isolates were significantly more resistant to phagocytosis (P = 0.0029) than M-type non-K1/K2, no significant difference in the phagocytosis rate was observed between K1/K2 isolates with M-type and non-M-type (P = 0.0924) . Mucoidy is an associated factor that was predominant in K1/K2 isolates, but which itself is not an independent influence on phagocytic resistance . The K1/K2 CPS proved significantly more resistant to phagocytosis than non-K1/K2 CPS in liver abscess isolates (P < 0.0001) and non-abscess isolates (P = 0.0001), suggesting that K1/K2 isolates were generally more virulent in both liver abscess and in non-liver abscess conditions . These findings indicate that resistance of CPS K1 or K2 K . pneumoniae to phagocytosis and intracellular killing presumably contributes to their high prevalence in liver abscess and uniquely in endophthalmitis.

J Antimicrob Chemother, 2004 Dec, 54(6), 1130 - 1133 Epub 2004 Oct 14.
Cefepime and the inoculum effect in tests with Klebsiella pneumoniae producing plasmid-mediated AmpC-type {beta}-lactamase; Kang CI et al.; OBJECTIVE: In the past decade, a new problem in Klebsiella pneumoniae strains has emerged: plasmid-mediated AmpC enzymes . This study was conducted to investigate the activity of cefepime against clinical isolates by determining the activities of cefepime and three other parenteral beta-lactam agents in standard and high inoculum MIC tests . METHODS: A total of 61 K . pneumoniae blood isolates, including 28 isolates producing AmpC-type beta-lactamases (14 isolates of DHA-1 and 14 isolates of CMY-1-like) and 33 isolates producing extended-spectrum beta-lactamases (ESBLs) (32 isolates of TEM- or SHV-related and one isolate of CTX-M-14-like), were included in the study . Antimicrobial susceptibilities were determined using broth microdilution MIC tests with standard and 100-fold-higher inocula . The inoculum effect was defined as an eight-fold or greater MIC increase on testing with the higher inoculum . RESULTS: In tests with AmpC beta-lactamase-producing K . pneumoniae isolates and their transconjugants, the inoculum effect was most consistently detected with cefepime, cefotaxime and ceftazidime, as inoculum effects were consistently detected in ESBL-producing isolates . However, the inoculum effect was least frequently detected with imipenem . CONCLUSION: Although the inoculum effect is an in vitro laboratory phenomenon, these results suggest that cefepime may be a less than reliable agent for therapy in cases of high inoculum infections caused by AmpC beta-lactamase-producing K . pneumoniae.

Biotechnol Lett, 2004 Aug, 26(16), 1301 - 6
Improved process for exopolysaccharide production by Klebsiella pneumoniae sp . pneumoniae by a fed-batch strategy; Ramirez-Castillo ML et al.; Exopolysaccharide (EPS) was produced by Klebsiella pneumoniae K63 grown in fed-batch cultures using different procedures of the supply of carbon or nitrogen (N) source, or both . Cultures grown with excess of glucose and limitation or exhaustion of N produced 54.8 and 47.4 g(EPS) l(-1), respectively . These cultures also led to an accumulation of 'overflow' metabolites representing more than 16% of carbon conversion . The consistency indexes ( K ) obtained to the end of the cultures, characteristic of the rheological property of the biopolymer, were 16.4 Pa s(n) for N deficiency and 5.2 Pa s(n) for N limitation conditions . The simultaneous limitation of glucose and N decreased the excretion of co-metabolites (6.4% of carbon conversion) and the EPS production (18.1 g(EPS) l(-1)), while improving the quality of the polysaccharide, characterized by the highest K of 126.2 Pa s(n) and the highest pseudoplasticity degree (flow behaviour index, n=0.2).

Zh Mikrobiol Epidemiol Immunobiol, 2004 Jul-Aug, (4), 7 - 11
{Proteinase activity of Klebsiella pneumoniae of different virulence}; Acute exacerbation of chronic hepatitis B during thalidomide therapy for multiple myeloma: a case report; Department of Internal Medicine, Gachon Medical School, Incheon, KoreaWe report a case of acute fatal exacerbation of chronic hepatitis B in a 50-year-old man with multiple myeloma being treated with thalidomide . The patient had a medical history of chronic hepatitis B and was diagnosed with stage IIIA multiple myeloma . He suffered two episodes of transient transaminitis of unknown origin after successive autologous stem cell transplantations . Spontaneous resolutions of the transaminitis were observed without special management . At that time, PCR of hepatitis B virus (HBV) were all-negative . After 5-months' administration of thalidomide for the second relapse of the multiple myeloma, he suddenly experienced dizziness and jaundice . The level of HBV DNA was 1,641 pg/mL and the serologic tests for other viruses were negative . Despite conventional supportive care, he expired due to septic shock caused by Klebsiella pneumonia . Based on the stable disease status of the multiple myeloma and exclusion of other hepatotoxic agents, it was assumed that the exacerbation of the hepatitis B virus during the thalidomide therapy preceded the bacterial sepsis . With the increased use of thalidomide in cancer treatment, cautious monitoring of the viral burden should be performed in patients with chronic hepatitis B.

Eur J Clin Microbiol Infect Dis, 2004 Nov, 23(11), 813 - 7 Epub 2004 Nov.
Evaluation of the current National Committee for Clinical Laboratory Standards guidelines for screening and confirming extended-spectrum beta-lactamase production in isolates of Escherichia coli and Klebsiella species from bacteremic patients; Katz OT et al.; The National Committee for Clinical Laboratory Standards (NCCLS) recommendations for screening and confirming the production of extended-spectrum beta-lactamases (ESBLs) were evaluated in 115 isolates of Escherichia coli and 157 isolates of Klebsiella spp . from Israeli patients with bacteremia . All isolates were screened using cefotaxime, ceftazidime, and cefpodoxime discs . Confirmatory tests using pairs of discs containing ceftazidime, cefotaxime, or cefpodoxime in which clavulanic acid was added to one of the discs in each pair {inhibitor-potentiated disc diffusion test (IPDDT)} and two double-sided E test strips containing ceftazidime or cefotaxime with and without clavulanic acid were performed on all isolates regardless of the results of screening tests . Isolates that tested positive by one or more confirmatory tests were considered ESBL producers . Overall, 69 (25.4%) strains were found to be ESBL producers . The sensitivity of the NCCLS screening criteria ranged between 98.6% for cefotaxime and 92.8% for ceftazidime, and the specificity ranged between 100% for cefotaxime and cefpodoxime and 99.0% for ceftazidime . The sensitivity of the confirmatory tests ranged between 97.1% for the cefotaxime E test and only 75.4% for the ceftazidime IPDDT discs . All 64 isolates that fell in the intermediate and resistant categories for cefotaxime, as well as all 41 in the same categories for ceftazidime and 68 of 69 in these categories for cefpodoxime, were confirmed as ESBL producers . The use of multiple antimicrobial discs for screening isolates and combinations of IPPDT discs is needed to improve the sensitivity of confirmatory testing . It is recommended that isolates falling in the intermediate and resistant categories in disc diffusion testing be reported as ESBL producers . The use of confirmatory tests should be limited to organisms with inhibition zone diameters ranging between the NCCLS recommendations for ESBL screening and the intermediate category breakpoints.

Nucleic Acids Res . 2004 Oct 08;32(18):e138.
KpnBI is the prototype of a new family (IE) of bacterial type I restriction-modification system; Chin V et al.; KpnBI is a restriction-modification (R-M) system recognized in the GM236 strain of Klebsiella pneumoniae . Here, the KpnBI modification genes were cloned into a plasmid using a modification expression screening method . The modification genes that consist of both hsdM (2631 bp) and hsdS (1344 bp) genes were identified on an 8.2 kb EcoRI chromosomal fragment . These two genes overlap by one base and share the same promoter located upstream of the hsdM gene . Using recently developed plasmid R-M tests and a computer program RM Search, the DNA recognition sequence for the KpnBI enzymes was identified as a new 8 nt sequence containing one degenerate base with a 6 nt spacer, CAAANNNNNNRTCA . From Dam methylation and HindIII sensitivity tests, the methylation loci were predicted to be the italicized third adenine in the 5' specific region and the adenine opposite the italicized thymine in the 3' specific region . Combined with previous sequence data for hsdR, we concluded that the KpnBI system is a typical type I R-M system . The deduced amino acid sequences of the three subunits of the KpnBI system show only limited homologies (25 to 33% identity) at best, to the four previously categorized type I families (IA, IB, IC, and ID) . Furthermore, their identity scores to other uncharacterized putative genome type I sequences were 53% at maximum . Therefore, we propose that KpnBI is the prototype of a new 'type IE' family.

J Clin Microbiol, 2004 Oct, 42(10), 4799 - 802
New method for laboratory detection of AmpC beta-lactamases in Escherichia coli and Klebsiella pneumoniae; Nasim K et al.; A new cefoxitin-agar medium (CAM)-based assay was compared to the previously published modified three-dimensional (M3D) assay for the detection of AmpC production in Escherichia coli and Klebsiella pneumoniae . Clinical isolates of cefoxitin-resistant E . coli (n = 5) and K . pneumoniae (n = 7) and multiple control strains with and without AmpC enzymes were tested by both methods . The CAM method with 4 microg of cefoxitin/ml was equivalent to the M3D method for detecting AmpC production in E . coli and K . pneumoniae . This new method is easier to perform and interpret and allows for testing of multiple isolates on a single plate.

J Antimicrob Chemother, 2004 Nov, 54(5), 881 - 888 Epub 2004 Oct 7.
Outbreak of multi-resistant Klebsiella oxytoca involving strains with extended-spectrum {beta}-lactamases and strains with extended-spectrum activity of the chromosomal {beta}-lactamase; Decre D et al.; OBJECTIVES: This study was conducted to analyse broad-spectrum cephalosporin-resistant Klebsiella oxytoca strains . METHODS: The 57 isolates studied were recovered from clinical specimens (n=23) or from rectal swabs (n=34) during a 26-month period . Antibiotic susceptibility patterns were determined using standard agar diffusion and dilution methods including the synergy test between extended-spectrum cephalosporins and clavulanic acid . ERIC-2 PCR and pulsed-field gel electrophoresis (PFGE) methods were used to study the clonal relatedness of the strains . Plasmid-mediated and chromosomal beta-lactamases were characterized by mating and specific bla gene amplification and sequencing . RESULTS: Four different antibiotic resistance patterns were identified whereas ERIC-2 PCR and PFGE revealed six main profiles . Extended-spectrum beta-lactamases (ESBLs) were found in 32 strains: TEM-7 (n=26), TEM-129 (n=1), TEM-3 (n=4), SHV-2 (n=1) . The new TEM-type beta-lactamase, TEM-129, differed from TEM-7 by one mutation (Glu-104-->Lys) . All TEM-7 or TEM-129 producers were genetically related . Twenty-five other strains with identical ERIC-2 PCR and PFGE profiles harboured a bla(OXY-2) gene different from the reference gene: 24 strains displayed one substitution (Ala-237-->Ser) in the KTG motif and one strain, highly resistant to ceftazidime, showed an additional substitution (Pro-167-->Ser) . CONCLUSIONS: The study demonstrated that the majority of strains (n=52) harbouring the OXY-2-type beta-lactamase corresponded to two clones . The first clone (n=27) corresponded to ESBL-producing strains . The second clone (n=25) displayed extended-spectrum activity of the chromosomal beta-lactamase.

J Immunol, 2004 Oct 15, 173(8), 5148 - 55
CpG oligodeoxynucleotides stimulate protective innate immunity against pulmonary Klebsiella infection; Deng JC et al.; Bacterial pneumonia is a leading cause of mortality in the United States . Innate immune responses, including type-1 cytokine production, are critical to the effective clearance of bacterial pathogens from the lung . Synthetic oligodeoxynucleotides (ODN) containing unmethylated CpG dinucleotide motifs (CpG ODN), which mimic the effects of bacterial DNA, have been shown to enhance type-1 cytokine responses during infection due to intracellular pathogens, resulting in enhanced microbial clearance . The role of CpG ODN in modulating protective innate immunity against extracellular pathogens is unknown . Using a murine model of Gram-negative pneumonia, we found that CpG ODN administration stimulated protective immunity against Klebsiella pneumoniae . Specifically, intratracheal (i.t.) administration of CpG ODN (30 microg) 48 h before i.t . K . pneumoniae challenge resulted in increased survival, compared with animals pretreated with control ODN or saline . Pretreatment with CpG ODN resulted in enhanced bacterial clearance in lung and blood, and higher numbers of pulmonary neutrophils, NKT cells, gammadelta-T cells, and activated NK1.1+ cells and gammadelta-T lymphocytes during infection . Furthermore, pretreatment with CpG ODN enhanced the production of TNF-alpha, and type-1 cytokines, including IL-12, IFN-gamma, and the IFN-gamma-dependent ELR- CXC chemokines IFN-gamma-inducible protein-10 and monokine induced by IFN-gamma in response to Klebsiella challenge, compared with control mice . These findings indicate that i.t . administration of CpG ODN can stimulate multiple components of innate immunity in the lung, and may form the basis for novel therapies directed at enhancing protective immune responses to severe bacterial infections of the lung.

J Wildl Dis, 2004 Jul, 40(3), 588 - 93
Struvite penile urethrolithiasis in a pygmy sperm whale (Kogia breviceps); Harms CA et al.; Massive urolithiasis of the penile urethra was observed in an adult pygmy sperm whale (Kogia breviceps) stranded on Topsail Island, North Carolina, USA . Calculi occupied the urethra from just distal to the sigmoid flexure to the tip of the penis for a length of 43 cm . A urethral diverticulum was present proximal to the calculi . The major portion of the multinodular urolith weighed 208 g and was 16 cm long x 3.7 cm diameter at the widest point . The urolith was composed of 100% struvite (magnesium ammonium phosphate) and on culture yielded Klebsiella oxytoca, a urease-positive bacterium occasionally associated with struvite urolith formation in domestic animals . Reaction to the calculi was characterized histologically by moderate multifocal to coalescing plasmacytic balanitis and penile urethritis . Role of the urethrolithiasis in the whale's stranding is speculative but could have involved pain or metabolic perturbations such as uremia or hyperammonemia.

Photochem Photobiol, 2004 Dec, 80(3), 542 - 7
Purification and Initial Characterization of a Putative Blue Light-regulated Phosphodiesterase from Escherichia coli paragraph sign; Rajagopal S et al.; The Escherichia coli protein YcgF contains a photosensory flavin adenine dinucleotide (FAD)-binding BLUF domain covalently linked to an EAL domain, which is predicted to have cyclic-di-guanosine monophosphate (GMP) phosphodiesterase activity . We have cloned, overexpressed and purified this protein, which we refer to as blue light-regulated phosphodiesterase (Blrp) for its putative activity . Blrp undergoes a reversible photocycle after exposure to light in which the spectrum of its photostationary state and kinetics of recovery of the dark state are similar to those of the isolated BLUF domain of the AppA protein . Unlike the AppA BLUF domain, the chromophore environment in the context of full-length Blrp is asymmetric, and the protein does not undergo any detectable global changes on exposure to blue light . When overexpressed in E . coli, Blrp copurifies with certain proteins which suggests that it plays a protective role in response to oxidative stress . Predicted proteins from Klebsiella pneumoniae and from a bacterium in the Sargasso Sea are similar to E . coli Blrp in both their BLUF and EAL domains, which suggests that blue light sensing in these bacteria may follow similar pathways.

Surg Neurol, 2004 Oct, 62(4), 362 - 5; discussion 365
Massive intracerebral air embolism associated with meningitis and lumbar spondylitis: case report; Kuo TH et al.; BACKGROUND: Massive intracerebral air embolism is a rare pathologic state and never in association with meningitis and lumbar spondylitis . To the best of our knowledge, our presented case is the first of a massive intracerebral air embolism associated with meningitis and lumbar spondylitis of Klebsiella pneumonia . CASE DESCRIPTION: A 55-year-old man presented with a high fever and low back pain . Blood culture showed Klebsiella pneumonia . Lumbar computed tomography (CT) revealed discitis at L1-2 and L2-3 levels and paraspinal abscess in which air was found . Despite management with antibiotics, patient's consciousness deteriorated, and brain CT revealed diffuse intravenous air embolism and severe brain swelling . Cerebrospinal fluid (CSF) examination demonstrated bacterial meningitis, and the CSF culture showed Klebsiella pneumonia . Later, septic shock occurred and patient expired . CONCLUSION: Intracerebral air embolism can occur in the Klebsiella pneumonia meningitis that resulted from lumbar spondylitis and sepsis.

Nepal Med Coll J, 2004 Jun, 6(1), 67 - 8
A blackening lady--case report; Biswas R et al.; A 40 year old lady presented with the classical clinical features of Addison's disease which on further investigations with an ultrasound abdomen showed a right suprarenal mass . This was subjected to a fine needle aspiration which revealed pus which on culture grew Klebsiella pneumoniae . Patient responded well to steroids and antibiotics . To the best of our knowledge this is the first report of Klebsiella pneumoniae in association with Addison's disease.

Antimicrob Agents Chemother, 2004 Oct, 48(10), 3720 - 8
Epidemiology and clinical features of bloodstream infections caused by AmpC-type-beta-lactamase-producing Klebsiella pneumoniae; Pai H et al.; Cases of bacteremia caused by AmpC-type-beta-lactamase-producing Klebsiella pneumoniae isolates were retrospectively studied to determine the epidemiologic features and clinical outcomes of bloodstream infections . Among 389 blood isolates recovered from 1998 to 2002, 65 isolates (16.7%) were found to be extended-spectrum beta-lactamase (ESBL) or AmpC beta-lactamase producers . The beta-lactamases from 61 of the 65 isolates were characterized; 28 of 61 isolates produced AmpC-type enzymes (14 isolates each produced DHA-1 and CMY-1-like enzymes), 32 isolates produced TEM or SHV-related ESBLs, and 1 isolate produced a CTX-M-14-like enzyme . To compare the clinical features and outcomes of bloodstream infections caused by AmpC producers with those caused by TEM- or SHV-related ESBL producers, 27 patients infected with isolates producing AmpC-type enzymes (AmpC group) and 25 patients infected with isolates producing TEM- or SHV-related enzymes (ESBL group) were analyzed . There was no significant difference between the AmpC and the ESBL groups in terms of risk factors . When the initial response was assessed at 72 h after antimicrobial therapy, the treatment failure rate for the AmpC group was 51.9% (14 of 27 patients) and the 7- and 30-day mortality rates were 14.8 and 29.6%, respectively, which were similar to those for the ESBL group . When the mortality rate for the patients who received extended-spectrum cephalosporins as definitive treatment was assessed, all four patients in the DHA-1 group and one of three patients in the CMY-1-like group died . In summary, the prevalence of AmpC enzyme-producing K . pneumoniae was high at the Seoul National University Hospital, and the clinical features and outcomes for the patients infected with AmpC-producing organisms were similar to those for the patients infected with TEM- or SHV-related ESBL producers.

Curr Microbiol, 2004 Oct, 49(4), 267 - 73
The electron transfer flavoprotein fixABCX gene products from Azospirillum brasilense show a NifA-dependent promoter regulation; Sperotto RA et al.; The complete nucleotide sequence of the A . brasilense fixA, fixB, fixC, and fixX genes is reported here . Sequence similarities between the protein sequences deduced from fixABCX genes and many electron transfer flavoproteins (ETFs) have been noted . Comparison of the amino acid sequences of both subunits of ETF with the A . brasilense fixA and fixB gene products exhibits an identity of 30% . The amino acid sequence of the other two genes, fixC and fixX, revealed similarity with the membrane-bound electron transfer flavoprotein ubiquinone oxidoreductase (ETF-QO) . Using site-directed mutagenesis, mutations were introduced in the fixA promoter element of the A . brasilense fixABCX operon and chimeric p fixA-lacZ reporter gene fusions were constructed . The activation of the fixA promoter of A . brasilense is dependent upon the presence of the NifA protein being approximately 7 times less active than the A . brasilense nifH promoter . These results indicate that NifA from Klebsiella pneumoniae activates the fix promoter of A . brasilense and provide further evidence in support of the regulatory model of NifA activation in A . brasilense . Although no specific function has been assigned to the fixABCX gene products they are apparently required for symbiotic nitrogen fixation . An electron-transferring capacity in the nitrogen fixation pathway has been suggested for the fix gene products based on sequence homologies to the ETFs and ETF-QO proteins and by the absence of orthologous electron transfer proteins NifJ and NifF in A . brasilense.

Scand J Immunol, 2004 Oct, 60(4), 351 - 5
The improved survival of experimental animals fed with fish oil is suppressed by a leukotriene inhibitor; Thors VS et al.; Fish oil is believed to alter the immune response and improve survival after infections in experimental animals . This effect may be due to altered production of the leukotrienes (LT) . We, therefore, performed a study in order to evaluate whether the effect of fish oil on the immune response of experimental animals is mediated through altered production of the LT . Female NMRI mice in four groups were fed with fish oil, fish oil with 5-lipoxygenase (5-LO) inhibitor (Zileuton, Abbott Laboratories, Chicago, IL, USA), corn oil or corn oil with 5-LO inhibitor . After 6 weeks, the mice were infected with Klebsiella pneumoniae and the survival was monitored . The experiment was performed twice . Analysis was performed mainly on data pooled from both experiments . The survival of the groups fed with fish oil was increased, compared to that of all the other groups and when compared to the groups fed with fish oil with 5-LO inhibitor (log-rank test) the difference was significant (P = 0.007) . It has been postulated that the effect of fish oil on the immune system is mediated through altered production of LT . In our study, blocking of the production of the LT eliminated the beneficial effects of fish oil . Our results are in concord with the hypothesis that the effect of fish oil is, at least partly, mediated through altered production of LT.

Chang Gung Med J, 2004 May, 27(5), 390 - 3
Nasal septal abscess as a complication of laser inferior turbinectomy; Lo SH et al.; Postoperative infections are infrequent following laser inferior turbinate surgery . We report a 52-year-old man with a Klebsiella pneumoniae nasal septal abscess as a complication of potassium-titanium-phosphate 532-nm laser turbinectomy . To our knowledge, this is the first report of such a potentially serious complication resulting from minor ambulatory intranasal surgery . The clinical presentation, pathogenesis, and management of nasal septal abscesses are discussed.

J Infect Chemother, 2004 Aug, 10(4), 212 - 5
Changes of antimicrobial resistance and extended-spectrum beta-lactamase production in Klebsiella spp . strains; Timko J; Changes of antimicrobial resistance and extended-spectrum beta-lactamase (ESBL) production of Klebsiella spp . strains isolated at the Central Military Hospital, Ruzomberok, Slovakia, with a special focus on the Anesthesiology--Resuscitation and Intensive Medicine Department during the years 1998-2002, were analyzed . Of 3920 gram-negative strains isolated from clinical materials during this period, Klebsiella spp . represented 8% . The incidence of ESBL-producing Klebsiella spp . isolates increased from 29% in 1998 to 69% in 2002 . Of 17 antibiotics tested, meropenem was found to be the most effective drug (100%) . The overall efficacy of cefotaxime was 31%, that of gentamicin 23%, and that of ciprofloxacin 54% . Analyzed Klebsiella isolates were characterized also by a high degree of multiresistance (53%) . The high incidence of reduced antibiotic susceptibility among Klebsiella spp . strains isolated at the intensive-care department suggests that more effective strategies are necessary to control the selection and spread of resistant organisms in this hospital.

J Immunol, 2004 Sep 15, 173(6), 4075 - 83
STAT4 is a critical mediator of early innate immune responses against pulmonary Klebsiella infection; Deng JC et al.; Bacterial pneumonia is a leading cause of morbidity and mortality in the U.S . An effective innate immune response is critical for the clearance of bacteria from the lungs . IL-12, a key T1 cytokine in innate immunity, signals through STAT4 . Thus, understanding how STAT4 mediates pulmonary immune responses against bacterial pathogens will have important implications for the development of rational immunotherapy targeted at augmenting innate immunity . We intratracheally administered Klebsiella pneumoniae to wild-type BALB/c and STAT4 knockout (STAT4-/-) mice . Compared with wild-type controls, STAT4-/- mice had decreased survival following intratracheal Klebsiella administration, which was associated with a higher lung and blood bacterial burden . STAT4-/- animals also displayed impaired pulmonary IFN-gamma production and decreased levels of proinflammatory cytokines, including the ELR- CXC chemokines IFN-gamma-inducible protein-10 and monokine induced by IFN-gamma . Although total lung leukocyte populations were similar between STAT4-/- and wild-type animals following infection, alveolar macrophages isolated from infected STAT4-/- mice had decreased production of proinflammatory cytokines, including IFN-gamma, compared with infected wild-type mice . The intrapulmonary overexpression of IFN-gamma concomitant with the systemic administration of IFN-gamma partially reversed the immune deficits observed in STAT4-/- mice, resulting in improved bacterial clearance from the blood . Collectively, these studies demonstrate that STAT4 is required for the generation of an effective innate host defense against bacterial pathogens of the lung .

J Mater Sci Mater Med, 1999, 10(10/11), 649 - 52
Investigation into the mechanism of bacterial adhesion to hydrogel-coated surfaces; Kunz R et al.; As a model for hydrogel-coated biomaterials, self-assembled monolayers of polyoxyethylene (POE) derivatives on sheets of polymeric biomaterials were prepared . The POE derivatives consisted of hydrophilic chains with different lengths and a long-chain alkyl group that served as an anchor function . The coatings obtained were analyzed with XPS and contact angle measurements showing hydrophilic chains of different lengths extending away from the surface . Bacterial adhesion was measured with a clinically relevant Klebsiella pneumoniae type strain and measurements reproduced 12 times . Bacterial adhesion decreased markedly with increasing hydrophilic chain length . Based upon these findings a new model for bacterial adhesion to hydrogel-coated surfaces is suggested: steric repulsion effects that increase with increasing chain length of grafted hydrophilic chains play an important role in bacterial adhesion to hydrogel-coated surfaces .

Appl Environ Microbiol, 2004 Sep, 70(9), 5441 - 6
Comparison of atomic force microscopy interaction forces between bacteria and silicon nitride substrata for three commonly used immobilization methods; Vadillo-Rodriguez V et al.; Atomic force microscopy (AFM) has emerged as a powerful technique for mapping the surface morphology of biological specimens, including bacterial cells . Besides creating topographic images, AFM enables us to probe both physicochemical and mechanical properties of bacterial cell surfaces on a nanometer scale . For AFM, bacterial cells need to be firmly anchored to a substratum surface in order to withstand the friction forces from the silicon nitride tip . Different strategies for the immobilization of bacteria have been described in the literature . This paper compares AFM interaction forces obtained between Klebsiella terrigena and silicon nitride for three commonly used immobilization methods, i.e., mechanical trapping of bacteria in membrane filters, physical adsorption of negatively charged bacteria to a positively charged surface, and glutaraldehyde fixation of bacteria to the tip of the microscope . We have shown that different sample preparation techniques give rise to dissimilar interaction forces . Indeed, the physical adsorption of bacterial cells on modified substrata may promote structural rearrangements in bacterial cell surface structures, while glutaraldehyde treatment was shown to induce physicochemical and mechanical changes on bacterial cell surface properties . In general, mechanical trapping of single bacterial cells in filters appears to be the most reliable method for immobilization.

Bacteriol Virusol Parazitol Epidemiol, 2003 Apr-Sep, 48(2-3), 130 - 4
{The sensitivity of some strains of Klebsiella spp . collected in a neonatal department}; Craciunescu M et al.; In order to analyse the evolution of the sensitivity to antibiotics of same strains with nosocomial potential such as Klebsiella isolated in a hospital, we took into study a number of 976 samples, collected in a new-born care department of the "Dr . D . Popescu" hospital Timisoara . The study took place between November-December 2002 . The collected samples were pharyngeal swabs, nasal swabs, gastric aspirates, ocular and umbilical secretions, vernix, urines, faeces and blood . From all these samples 803 strains with nosocomial potential were isolated, 84 strains being Klebsiella spp . Most of the isolated strains presented multiple phenotypes of resistance to antibiotics.

Bacteriol Virusol Parazitol Epidemiol, 2003 Apr-Sep, 48(2-3), 118 - 22
{Bacterial strains isolated in high nosocomial risk departments}; Muntean D et al.; We collected 312 samples from hospitalized patients in two hospitals in Timisoara between September-December 2003 . We isolated 83 strains with nosocomial potential . Identification of the germs was performed using the automatic API system, and the susceptibility tests were performed using disc-diffusion and the agar dilution test . By analyzing the extended antibiograms we categorized the germs considering their phenotypes of resistance and we remarked a high percentage of E . coli, Klebsiella pneumoniae pneumoniae and S . aureus with multiple resistance to antibiotics.

J Microbiol Immunol Infect, 2004 Aug, 37(4), 208 - 15
Evidence for arylamine N-acetyltransferase activity in Klebsiella pneumoniae; Hui CS et al.; Arylamine N-acetyltransferase (NAT) enzymes have been found in laboratory animals, humans, microorganisms (fungi, bacteria and parasites), and in plants . But the characteristics of NAT from Klebsiella pneumoniae are not clear . NAT activities with p-aminobenzoic acid (PABA) and 2-aminofluorene (AF) as substrates were examined in the cytosol of K . pneumoniae . NAT activity (N-acetylation of substrates) was determined using an acetyl coenzyme A recycling assay and high performance liquid chromatography for determining the amounts of acetylated or non-acetylated PABA or AF . NAT activities from a number of K . pneumoniae isolates were found to be 0.72 +/- 0.08 nmol/min/mg protein for AF, and 0.49 +/- 0.04 nmol/min/mg protein for PABA . The kinetic parameters of apparent Michaelis constant (Km) and maximum velocity (Vmax) obtained were 2.92 +/- 0.48 mM and 7.89 +/- 0.82 nmol/min/mg protein, respectively, for AF and 2.42 +/- 0.28 mM and 9.87 +/- 0.64 nmol/min/mg protein, respectively, for PABA . The optimal pH value for the NAT activity was 7.0 for AF and PABA . The optimal temperature for NAT activity was 37 degrees C for both substrates . The NAT activity was inhibited by 50% with 0.25 mM iodoacetamide, and by more than 90% at 1.0 mM . Among a series of divalent cations and salts, Cu2+ and Zn2+ were the most potent inhibitors of NAT activity.

Jpn J Infect Dis, 2004 Aug, 57(4), 150 - 5
Protective role of liposome incorporated lipopolysaccharide antigen of Klebsiella pneumoniae in a rat model of lobar pneumonia; Chhibber S et al.; In a lobar pneumonia model of Klebsiella pneumoniae, the immunoprotective role of free lipoploysaccharide (LPS) and liposome-incorporated LPS was studied . An alteration in the biological activity of the LPS molecule, in terms of its pyrogenicity and lethal toxicity, was observed on incorporation in the liposome . Compared at equal doses, liposome-incorporated LPS was found to be non-pyrogenic and 10 times less toxic than free LPS . Liposome-incorporated LPS was more effective in providing protection against K . pneumoniae induced lobar pneumonia in rats . The immunological mechanism underlying protection revealed involvement of both nonspecific and specific immune response . Alveolar macrophage activation was observed after 4 and 14 days of treatment with the free and liposome-entrapped forms of LPS, respectively . Specific immunity in terms of plaque-forming cells was seen with both forms of LPS . Delayed type hypersensitivity reaction was observed only with liposome-incorporated LPS . It is concluded that a non-toxic and immunogenic form of K . pneumoniae LPS can be obtained by incorporation of the native preparation into liposomes.

J Dairy Sci, 2004 Aug, 87(8), 2420 - 32
Characterization of the bovine innate immune response to intramammary infection with Klebsiella pneumoniae; Bannerman DD et al.; Gram-negative bacteria are responsible for almost one-half of the clinical cases of mastitis that occur annually . Of those gram-negative bacteria that induce mastitis, Klebsiella pneumoniae remains one of the most prevalent . Detection of infectious pathogens and the induction of a proinflammatory response are critical components of host innate immunity . The objective of the current study was to characterize several elements of the bovine innate immune response to intramammary infection with Klebsiella pneumoniae . The inflammatory cytokine response and changes in the levels of soluble CD14 (sCD14) and lipopolysaccharide (LPS)-binding protein (LBP), 2 proteins that contribute to host recognition of gram-negative bacteria, were studied . The contralateral quarters of 7 late-lactating Holstein cows were challenged with either saline or K . pneumoniae, and milk and blood samples were collected . Initial increases in the chemoattractants C5a and IL-8, as well as TNF-alpha, were evident in infected quarters within 16 h of challenge and were temporally coincident with increases in milk somatic cells . Augmented levels of TNF-alpha and IL-8 were observed in infected quarters until >48 h postchallenge, respectively . Elevated levels of IL-12, IFN-gamma, and the antiinflammatory cytokine, IL-10, which were first detected between 12 and 20 h postinfection, persisted in infected quarters throughout the study (>96 h) . Initial increases in milk LBP and sCD14 were detected 16 and 20 h, respectively, after challenge . Together, these data demonstrate that intramammary infection with K . pneumoniae elicits a host response characterized by the induction of proinflammatory cytokines and elevation of accessory molecules involved in LPS recognition.

Antimicrob Agents Chemother, 2004 Sep, 48(9), 3477 - 82
Increased serum resistance in Klebsiella pneumoniae strains producing extended-spectrum beta-lactamases; Sahly H et al.; The aim of this study was to determine whether there is an association between serum resistance, O serotypes, and the production of extended-spectrum beta-lactamases (ESBLs) in Klebsiella pneumoniae . Ninety ESBL-producing and 178 non-ESBL-producing K . pneumoniae isolates gathered in five European countries were O serotyped and tested for sensitivity to the serum's bactericidal effect . The frequency of serum-resistant isolates was higher among ESBL-producing strains (30%; 27/90 isolates) than among non-ESBL-producing strains (17.9%; 32/178 isolates) (P = 0.037; odds ratio {OR} = 1.96; 95% confidence interval {95% CI} = 1.08 to 3.53) . Although O1 was the most common O serotype in both Klebsiella groups, its frequency among ESBL-producing strains was significantly higher (59%; 53/90 isolates) than among non-ESBL producers (36%; 64/178 isolates) (P = 0.0006; OR = 2.5; 95% CI = 1.52 to 4.29) . Furthermore, the prevalence of the O1 serotype was higher among serum-resistant strains of both ESBL-producing (74%; 20/27isolates) and non-ESBL producers (75%; 24/32 isolates) than among serum-sensitive ESBL producers (52.4%; 33/63 isolates) and non-ESBL producers (27.4%; 40/146 isolates) . Serum resistance among ESBL-producing strains (36%; 17/47 isolates) versus non-ESBL-producing strains (16%; 27/166 isolates) was also significantly higher after the exclusion of clonal strains (P = 0.0056; OR = 2.9; 95% CI = 1.41 to 6.01) . Sixteen ESBL types were detected, among which the frequency of serum resistance was significantly lower among the SHV-producing strains (9/48 isolates) than among the TEM producers (16/35 isolates) (P = 0.016; OR = 3.65; CI = 1.3 to 9.7) . Curing ESBL-coding plasmids did not influence the serum resistance of the bacteria; all six plasmid-cured derivatives maintained serum resistance . The present findings suggest that ESBL-producing strains have a greater pathogenic potential than non-ESBL-producing strains, but the linkage between O serotypes, serum resistance, and ESBL production remains unclear at this stage.

Zhonghua Nei Ke Za Zhi, 2004 Jul, 43(7), 487 - 90
{Plasmid-mediated cephalosporinase among extended-spectrum-beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae}; Wang QT et al.; OBJECTIVE: To investigate the prevalence and genotype of plasmid-mediated cephalosporinase (AmpC) beta-lactamase in extended-spectrum-beta-lactamase-producing (ESBL) Escherichia coli and Klebsiella pneumoniae . METHODS: 24 strains of cefoxitin-resistant ESBL-producing E . coli and 8 strains of K . pneumoniae were collected from January to December 2001 at Beijing Chaoyang Hospital . Analytical isoelectric focusing electrophoresis was used to measure the pI of the beta-lactamase . Conjugation experiment was used to study the transfer of cefoxitin resistance . The homology of the isolates was determined by pulsed field gel electrophoresis (PFGE) . Plasmid-mediated AmpC enzyme genes were amplified and sequenced by using multiplex PCR . RESULTS: The prevalence of ESBL-producing E . coli and K . pneumoniae were 16.8% (49/292) and 16.5% (35/212), respectively . The prevalence of AmpC enzyme among ESBL-producing E . coli and K . pneumoniae isolates were 2.0% (1/49) and 17.1% (6/35), respectively . These 7 isolates produced DHA-1 AmpC enzyme . One strain of K . pneumoniae could transfer cefoxition resistance to the recipient . Among 7strains, 5 strains produced CTX-M-3 and 2 produced SHV-12 ESBL . These 7 strains also produced TEM-1 broad-spectrum enzymes . These strains harbored 2 - 5 plasmids and one of them were 33 - 36 kb . PFGE showed these strains came from a variety of clones . CONCLUSIONS: In this hospital, 7 strains of the ESBL-positive E . coli and K . pneumoniae produced both DHA-1AmpC enzyme and CTX-M-3/SHV-12 ESBL . These 7 strains were from different clones.

Lik Sprava, 2001 Jan-Feb, (1), 97 - 102
{Pathomorphological aspects and outcome of influenza virus and Klebsiella pneumonia in the experiment}; Anisimova IuN; Mice infected with K . pneumoniae against the background of prior introduction of influenza A/Hong-Kong/68 virus developed focal bronchial pneumonia with leukocytic exudate that started resolving at day 10 of the experiment . At about this time and later there appeared in the lungs spots of apparent proliferative processes characteristic of productive inflammation . These were manifested by diffuse and focal infiltration of the interstice with plasmablasts, plasmacytes, histiocytes, lymphocytes, by proliferation of the vascular endothelium epithelium, of the bronchi, bronchioles, alveolar cells that were seen to be desquamative and developing obliterating macrophagal alveolitis, focal proliferation of fibroblasts . Abnormalities in immunoregulatory mechanisms were induced by immunodepressive action of the influenza virus, early chronization of viral-bacterial pneumonia, with pneumosclerosis developing in its wake.

J Korean Med Sci, 2004 Aug, 19(4), 608 - 10
Klebsiella pneumoniae Septic Arthritis in a Cirrhotic Patient with Hepatocellular Carcinoma; Park CH et al.; Despite septic arthritis is increasingly being reported in elderly patients with diabetes or alcoholism, reported cases of spontaneous bacterial arthritis in cirrhotic patients are extremely rare . We present the first reported case of K . pneumoniae septic arthritis and spontaneous bacterial peritonitis in a cirrhotic patient with hepatocellular carcinoma . K . pneumoniae, one of the most common causative organisms of spontaneous bacterial peritonitis in cirrhotic patients, was isolated from both the blood and the joint fluid, which suggests that the route of infection was hematogenous . After the treatment with cefotaxime and closed tube drainage, the condition of the patient was improved, and subsequently, the joint fluid became sterile and the blood cultures were proved negative . Therefore, this case provides further evidence for the mode of infection being bacteremia in cirrhotic patients and suggests that the enteric bacteremia in cirrhotics may cause infection in different organ systems . Copyright The Korean Academy of Medical Sciences

Clin Microbiol Infect, 2004 Aug, 10(8), 760 - 2
Results of two worldwide surveys into physician awareness and perceptions of extended-spectrum beta-lactamases; Goossens H et al.; An omnibus survey of microbiologists (n = 400) and a survey of participants (n = 49) in the Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) programme were conducted to determine the awareness and prevalence of extended-spectrum beta-lactamases (ESBLs), and the regularity and method of screening . Of the omnibus survey participants, 69% screened regularly for ESBLs, compared with 83% of MYSTIC participants . In both surveys, ESBLs were more common in Klebsiella pneumoniae (73% and 79%, respectively) and Escherichia coli (63% and 81%, respectively) than in other bacteria . The surveys demonstrated that awareness of, and testing for, ESBLs is inconsistent.

Acta Crystallogr D Biol Crystallogr, 1997 Mar, 53(Pt 2), 227 - 8
Crystallization and preliminary X-ray studies of nitrogenase component 1 (the MoFe protein) from Klebsiella pneumoniae; Roe SM; Two crystal forms of component 1 (the MoFe protein) of nitrogenase from Klebsiella pneumoniae have been isolated and characterized . The triclinic form has cell dimensions a = 76.0, b = 109.6, c = 144.6 A, alpha = 80.3, beta = 74.9 and gamma = 69.6 degrees, diffracts to around 3.0 A and has two molecules in the asymmetric unit . The monoclinic form belongs to space group P2(1) with a = 76.6, b = 127.8, c = 109.1 A and beta = 104.6 degrees (frozen at 100 K), diffracts to 1.5 A and has one molecule in the asymmetric unit . At this resolution the outstanding questions concerning the structure and the operation of the enzyme, in particular the linkage between the Fe(4)S(4) units in the P clusters, the true geometry of the apparently trigonal Fe atoms in the FeMoco and the reduction site itself, should be answerable.

J Clin Microbiol, 2004 Aug, 42(8), 3388 - 98
Molecular serotyping of Klebsiella species isolates by restriction of the amplified capsular antigen gene cluster; Brisse S et al.; The objective of the present work was to develop a molecular method that would enable determination of the capsular serotypes of Klebsiella isolates without the use of antiserum . PCR amplification of the capsular antigen gene cluster (cps) was followed by digestion with the restriction enzyme HincII (cps PCR-restriction fragment length polymorphism {RFLP} analysis) . The profiles (C patterns) obtained for 224 strains representing the 77 known K serotypes showed 3 to 13 fragments ranging in size from 0.2 to 4.4 kb . A total of 97 distinct C patterns were obtained; 100% of 61 pairs of samples tested twice showed reproducible C patterns . The C patterns were K-type specific; i.e., the C pattern(s) of any K serotype was distinct from the C patterns of all other K serotypes, with the only exceptions being serotypes K22 and K37, which are known to cross-react . For 12 of 17 K types for which at least two strains were included, C-pattern variations were found among strains with the same K serotype . Therefore, cps PCR-RFLP analysis has a higher discriminatory power than classical K serotyping . C-pattern identity was observed among strains with a given K type that were collected many years apart and from distinct sources, indicating C-pattern stability . Only 4.5% of the strains were nontypeable, because of unsuccessful PCR amplification (whereas 8 to 23% are nontypeable by classical K serotyping) . Three of four noncapsulated strains analyzed showed recognizable C patterns . The K serotypes of 18 (82%) of 22 recent Klebsiella pneumoniae clinical isolates could be deduced from their C patterns . In conclusion, cps PCR-RFLP analysis allows determination of the K serotype, while it is easier to perform and more discriminatory than classical serotyping.

Biotechnol Prog, 2004 Jul-Aug, 20(4), 1069 - 75
Biokinetic evaluation and modeling of continuous thiocyanate biodegradation by Klebsiella sp; Ahn JH et al.; Biokinetics for autotrophic degradation of thiocyanate using batch culture of Klebsiella sp . were evaluated both analytically and numerically . A sequential approach with an analytical method followed by a numerical approximation was used to evaluate and to ensure the accuracy of the parameter estimation . The nonlinear least-squares method with a 95% confidence interval was employed . The growth conditions were maintained at pH 7 and 38 degrees C for all experiments . With an automated incubation and turbidity reader, a total of 16 different initial thiocyanate concentrations, ranging from 10 to 300 mg L(-1), were used to develop a kinetic expression of specific growth rate as a function of substrate concentration . The biodegradation of thiocyanate with Klebsiella sp . followed a substrate inhibition pattern . Three identical automated bioreactors with working volumes of 1.5 L, equipped with sterilizable sampling ports, were also used for the numerical approximation of the biokinetic parameters in batch mode . A fourth order Runge-Kutta method was used to approximate the substrate inhibition kinetics of the Klebsiella sp . utilizing thiocyanate . Although the kinetic coefficients estimated by analytical and numerical methods were not statistically different at a 0.05 alpha level, model responses of numerical approximation generated a better prediction of changes in thiocyanate and cell mass concentrations . The hypothetical maximum growth rate, micro m, half saturation coefficient, Ks, microbial yield coefficient, Y, cell mass decay rate coefficient, kd, and substrate inhibition coefficient, Ksi, were evaluated as being 0.62 +/- 0.05 d(-1), 85 +/- 8 mg SCN- L(-1), 0.076 +/- 0.011 mg cell mass (mg SCN)(-1), 0.03 +/- 0.002 d(-1), and 131 +/- 22 mg SCN- L(-1), respectively . The calculated maximal substrate concentration, Sm, and apparent maximum specific growth rate, micro'm, were 105.5 +/- 8.7 mg SCN- L(-1) and 0.24 +/- 0.01 d(-1), respectively . Using these estimated parameters, the theoretical performance of the continuous operation was also illustrated, which depicts the residual thiocyanate and Klebsiella sp . concentrations in the non-steady and steady states at different hydraulic retention times (HRTs) . Assuming the influent concentration of 250 mg SCN- L(-1), the expected treatment efficiency ranged from 94.9% to 69.4% between 20 and 5 days HRT, respectively . Klebsiella sp . was expected to be washed out at 4.8 days HRT, thus resulting in no treatment of thiocyanate.

Eur J Biochem, 2004 Aug, 271(16), 3379 - 88
GlnK effects complex formation between NifA and NifL in Klebsiella pneumoniae; Stips J et al.; In Klebsiella pneumoniae, the nif specific transcriptional activator NifA is inhibited by NifL in response to molecular oxygen and ammonium . Here, we demonstrate complex formation between NifL and NifA (approximately 1 : 1 ratio), when synthesized in the presence of oxygen and/or ammonium . Under simultaneous oxygen- and nitrogen-limitation, significant but fewer NifL-NifA complexes (approximately 1%) were formed in the cytoplasm as a majority of NifL was sequestered to the cytoplasmic membrane . These findings indicate that inhibition of NifA in the presence of oxygen and/or ammonium occurs via direct NifL interaction and formation of those inhibitory NifL-NifA complexes appears to be directly and exclusively dependent on the localization of NifL in the cytoplasm . We further observed evidence that the nitrogen sensory protein GlnK forms a trimeric complex with NifL and NifA under nitrogen limitation . Binding of GlnK to NifL-NifA was specific; however the amount of GlnK within these complexes was small . Finally, two lines of evidence were obtained that under anaerobic conditions but in the presence of ammonium additional NtrC-independent GlnK synthesis inhibited the formation of stable inhibitory NifL-NifA complexes . Thus, we propose that the NifL-NifA-GlnK complex reflects a transitional structure and hypothesize that under nitrogen-limitation, GlnK interacts with the inhibitory NifL-NifA complex, resulting in its dissociation.

Sichuan Da Xue Xue Bao Yi Xue Ban, 2004 Jul, 35(4), 470 - 2
{Studies on the nucleotides sequences of extended-spectrum-beta-lactamases encoding genes of Escherichia coli and Klebsiella pneumoniae and the related molecular evolution}; Chen X et al.; OBJECTIVE: To identify TEM-type and SHV-type ESBLs encoding genes of ESBLs-producing Klebsiella pneumoniae and Escherichia coli isolated from clinical species in West China Hospital of Sichuan University and study the molecular evolution of the ESBLs . METHODS: The nucleotide sequences of TEM-type and SHV-type ESBLs encoding genes amplified by PCR were detected by automatic sequencer, and the subtypes of the encoding genes were determined by Blastx searching . The molecular evolution of ESBLs was studied by means of bioinformatics . RESULTS: In this study, the subtypes of ESBLs were SHV-2 and TEM-19, the distribution of silent mutation in ten bla(SHV-2) was identical, and that of two bla(TEM-19) was the same; the distribution of silent mutation of bla(TEM-19) was the same as that of bla(TEM-1) . The distribution of silent mutation of bla(SHV-2) observed here was different from that observed in other countries . CONCLUSION: SHV-2 was the main ESBLs in this study . The bla(SHV-2) and bla(TEM-19) in this study originated from the same transferable variants respectively . The prevalent SHV-2 in different countries resulted from convergent evolution . It seems possible that the bla(TEM-19) identified by this study might originate directly from the transferable bla(TEM-1) identified in this study.

Gene, 2004 Aug 4, 337, 189 - 98
Sequencing and analysis of the large virulence plasmid pLVPK of Klebsiella pneumoniae CG43; Chen YT et al.; We have determined the entire DNA sequence of pLVPK, which is a 219-kb virulence plasmid harbored in a bacteremic isolate of Klebsiella pneumoniae . A total of 251 open reading frames (ORFs) were annotated, of which 37% have homologous genes of known function, 31% match the hypothetical genes in the GenBank database, and the remaining 32% are novel sequences . The obvious virulence-associated genes carried by the plasmid are the capsular polysaccharide synthesis regulator rmpA and its homolog rmpA2, and multiple iron-acquisition systems, including iucABCDiutA and iroBCDN siderophore gene clusters, Mesorhizobium loti fepBC ABC-type transporter, and Escherichia coli fecIRA, which encodes a Fur-dependent regulatory system for iron uptake . In addition, several gene clusters homologous with copper, silver, lead, and tellurite resistance genes of other bacteria were also identified . Identification of a replication origin consisting of a repA gene lying in between two sets of iterons suggests that the replication of pLVPK is iteron-controlled and the iterons are the binding sites for the repA to initiate replication and maintain copy number of the plasmid . Genes homologous with E . coli sopA/sopB and parA/parB with nearby direct DNA repeats were also identified indicating the presence of an F plasmid-like partitioning system . Finally, the presence of 13 insertion sequences located mostly at the boundaries of the aforementioned gene clusters suggests that pLVPK was derived from a sequential assembly of various horizontally acquired DNA fragments.

Antimicrob Agents Chemother, 2004 Aug, 48(8), 3203 - 6
Role of beta-lactamases and porins in resistance to ertapenem and other beta-lactams in Klebsiella pneumoniae; Jacoby GA et al.; High-level resistance to ertapenem was produced by beta-lactamases of groups 1, 2f, and 3 in a strain of Klebsiella pneumoniae deficient in Omp35 and Omp36 . From a wild-type strain producing ACT-1 beta-lactamase, ertapenem-resistant mutants for which the ertapenem MICs were up to 128 microg/ml and expression of outer membrane proteins was diminished could be selected.

Antimicrob Agents Chemother, 2004 Aug, 48(8), 2905 - 10
Molecular characterization of a cephamycin-hydrolyzing and inhibitor-resistant class A beta-lactamase, GES-4, possessing a single G170S substitution in the omega-loop; Wachino J et al.; The nosocomial spread of six genetically related Klebsiella pneumoniae strains producing GES-type beta-lactamases was found in a neonatal intensive care unit, and we previously reported that one of the six strains, strain KG525, produced a new beta-lactamase, GES-3 . In the present study, the molecular mechanism of cephamycin resistance observed in strain KG502, one of the six strains described above, was investigated . This strain was found to produce a variant of GES-3, namely, GES-4, which was responsible for resistance to both cephamycins (cefoxitin MIC, >128 microg/ml) and beta-lactamase inhibitors (50% inhibitory concentration of clavulanic acid, 15.2 +/- 1.7 microM) . The GES-4 enzyme had a single G170S substitution in the Omega-loop region compared with the GES-3 sequence . This single amino acid substitution was closely involved with the augmented hydrolysis of cephamycins and carbapenems and the decreased affinities of beta-lactamase inhibitors to GES-4 . A cloning experiment and sequencing analysis revealed that strain KG502 possesses duplicate bla(GES-4) genes mediated by two distinct class 1 integrons with similar gene cassette configurations . Moreover, the genetic environments of the bla(GES-4) genes found in strain KG502 were almost identical to that of bla(GES-3) in strain KG525 . From these findings, these two phenotypically different strains were suggested to belong to a clonal lineage . The bla(GES-4) gene found in strain KG502 might well emerge from a point mutation in the bla(GES-3) gene harbored by its ancestor strains, such as strain KG525, under heavy antibiotic stress in order to acquire extended properties of resistance to cephamycins and carbapenems.

Biotechnol Lett, 2004 Jun, 26(11), 911 - 5
1,3-Propanediol production by Klebsiella pneumoniae under different aeration strategies; Cheng KK et al.; 1,3-Propanediol production by Klebsiella pneumoniae was studied in batch cultures under N2 flow and four airflow systems . Different byproducts were formed under different aeration conditions . An anaerobic/aerobic combined fed-batch culture was developed giving 70 g 1,3-propanediol l(-1) and 16 g 2,3-butanediol l(-1) with total diol yield of 0.6 mol(-1) glycerol.

Regul Toxicol Pharmacol, 2004 Jun, 39 Suppl 1, S47 - 56
Safety evaluation of an alpha-cyclodextrin glycosyltranferase preparation; Bar A et al.; Alpha-cyclodextrin glucosyltransferase (alpha-CGTase, EC 2.4.1.19) is an amylolytic enzyme used for the production of alpha-cyclodextrin (alpha-CD), a novel, soluble dietary fiber, from food-grade starch . The safety of an alpha-CGTase preparation obtained by batch fermentation from a recombinant strain of Escherichia coli K12 harboring the alpha-CGTase gene from Klebsiella oxytoca strain M5a1 was examined . In a 13-week subchronic toxicity study in rats, the administration by gavage of the alpha-CGTase preparation at levels of up to 20 ml/kg bw/day, corresponding to a total organic solids dosage of 260 mg/kg bw/day, did not cause any systemic toxic effect . Some signs of irritation were observed in the respiratory tract which occurred, however, in one sex only and/or were not dose-related . Accordingly, these changes were considered to be an unspecific consequence of the reflux and aspiration of the dosing solution . There was no evidence of a genotoxic activity in Ames tests and a chromosome aberration test in cultured human lymphocytes . It is concluded that the examined alpha-CGTase preparation is safe when used for the production of alpha-CD.

Microb Drug Resist, 2004 Summer, 10(2), 132 - 8
Involvement of SHV-12 and SHV-2a encoding plasmids in outbreaks of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in a Tunisian neonatal ward; Ben-Hamouda T et al.; Previous genotypic investigations of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae recovered in a Tunisian neonatal ward revealed the spread of two epidemic strains and a high number of genetically unrelated isolates . The aim of the present study was to determine the role of the dissemination of self-transferrable plasmids harboring bla genes in the outbreaks experienced by the ward . The 49 previously identified clinical isolates of ESBL-producing K . pneumoniae were examined for relationships between their enzymes and plasmids . Analysis of crude extracts by isoelectric focusing showed four beta-lactamase-activities at pI 8.2, 7.6, 6, and 5.4 . Clinical isolates contained large plasmids that could be transferred by conjugation and transformation conferring resistance to expanded-spectrum cephalosporins . DNA amplification and sequencing were performed to confirm the identities of transferred beta-lactamases . Nucleotide sequence analysis of SHV-specific PCR products from six isolates identified two bla(SHV) genes corresponding to SHV derived ESBLs, SHV-12 and SHV-2a . PstI digestion of plasmid DNA from transformants revealed six restriction patterns . The occurrence of the prevalent plasmid pattern in both epidemic strains and unrelated isolates indicated that diffusion and endemic persistence of the bla(SHV-ESBL) genes in the ward were due to concomitant spread of epidemic strains and plasmid dissemination among unrelated strains.

Niger Postgrad Med J, 2004 Mar, 11(1), 26 - 31
Problems of management of burns injuries among children; Okoromah CN et al.; BACKGROUND: Contrary to our local experience, published data elsewhere show increased survival rates from major burns due to improvements in management . This study aimed at examining problems of burns management in children . DESIGN: Relevant data extracted from the records of 44 children included sociodemographic, clinical, management characteristics and outcomes . RESULTS: There were 86.0% thermal burns due to accidental, domiciliary events in 36 (81.8% . Mean (range) BSA was 35.9% +/- 4.0 (1%-95%), mostly 2nd degree burns in 34 (77.3%) . Mean (range) duration of symptoms before presentation was 1.1 +/- 0.3 days (1-7 days) . Following hospitalisation, involvement of key experts in acute burns care was either delayed or omitted . Intensive care monitoring and support including mechanical ventilation were unavailable for 11 (25.0%) cases with cardiorespiratory compromise . Septicaemia & pneumonias were associated with death in 9 (56.3%) of the 16 deaths . Klebsiella, pseudomonas and coliform organisms were isolated from most burns wound . Oral acetominophen and intramuscular dipyrone were the main analgesics used in 24 (54.6%) and 8 (18.2%) cases respectively . Anxiolytics were used in only 2 94.5%) . Case fatality rate was 36.4% . Mortalities were 100% with BSA 50-100% (p=0 . 000) . CONCLUSION: Prevention and improvements in management of burns including early multidisciplinary care, critical care support, aggressive wound care and adequate pain control should be emphasised.

Diagn Microbiol Infect Dis, 2004 Jul, 49(3), 217 - 22
Prevalence and characterization of extended-spectrum beta-lactamases in Klebsiella pneumoniae and Escherichia coli isolates from Colombian hospitals; Villegas MV et al.; Gram-negative pathogens harboring extended-spectrum beta-lactamases (ESBL) are widely prevalent in Latin America, but little is known about their prevalence in Colombia . A network of 8 tertiary care hospitals in Bogota, Medellin, and Cali, Colombia, was formed in January 2002 to determine the prevalence of ESBL-producing Klebsiella pneumoniae and Escherichia coli . We characterized and established the molecular epidemiology of ESBLs from these hospitals . Data from 1074 E . coli and 394 K . pneumoniae isolates were obtained from hospital laboratories during 6 months . Isolates resistant to third-generation cephalosporins or aztreonam were sent to a central laboratory . The prevalence of strains with this phenotype was 32.6% in K . pneumoniae and 11.8% in E . coli from the intensive care units, with slightly lower percentages from wards . Although TEM and SHV enzymes were present, the dominant class was CTX-M . Molecular typing of chromosomal DNA showed that most strains were not clonal.

J Clin Microbiol, 2004 Jul, 42(7), 2902 - 6
Molecular characterization of extended-spectrum beta-lactamases produced by clinical isolates of Klebsiella pneumoniae and Escherichia coli from a Korean nationwide survey; Jeong SH et al.; To determine the prevalence and genotypes of extended-spectrum beta-lactamases (ESBLs) among clinical isolates of Klebsiella pneumoniae and Escherichia coli, we performed antibiotic susceptibility testing, pI determination, induction testing, transconjugation, and DNA sequencing analysis . Among the 509 isolates collected from 13 university hospitals in Korea, 39.2% produced ESBLs . ESBL-producing isolates were detected in every region in Korea . A total of 44.6% of the isolates produced both TEM- and SHV-type ESBLs, and 52% of ESBL-producing isolates transferred resistance to ceftazidime by transconjugation . The ESBLs were TEM-19, TEM-20, TEM-52, SHV-2a, SHV-12, and one new variant identified for the first time in Korea, namely, TEM-116 . TEM-1 and SHV-12 were by far the most common variants . TEM-1, TEM-116, and SHV-12 showed a high prevalence in K . pneumoniae . Two isolates (E . coli SH16 and K . pneumoniae SV3) produced CMY-1-like beta-lactamases, which play a decisive role in resistance to cefoxitin and cefotetan, as well as TEM-type enzymes (TEM-20 and TEM-52, respectively) . Using MIC patterns and DNA sequencing analysis, we postulated a possible evolution scheme among TEM-type beta-lactamases in Korea: from TEM-1 to TEM-19, from TEM-19 to TEM-20, and from TEM-20 to TEM-52.

Pediatr Blood Cancer, 2004 Aug, 43(2), 170 - 6
Management of coagulopathy with recombinant factor VIIa in a neonate with echovirus type 7; Tancabelic J et al.; A 5-day-old newborn presented with neonatal enteroviral infection . The patient's hospital course was complicated by acute liver dysfunction, renal insufficiency, fluid overload, respiratory failure, hypertension, catheter related thrombosis, Klebsiella pneumoniae sepsis, intracerebral and intraventricular hemorrhage, and disseminated intravascular coagulation (DIC) . Administration of fresh frozen plasma (FFP) and cryoprecipitate failed to control the patient's hemostasis and led to significant fluid overload . Recombinant activated factor VII (rFVIIa, Novoseven NovoNordisk, Bagsvaerd, Denmark) was given to the neonate as a bolus (rFVIIa at 60-80 microg/kg body weight), followed by a continuous infusion (2.5-16 microg/kg/hr) . Recombinant activated factor VII controlled hemostasis, until the patient's liver function recovered . The patient's blood product requirement significantly decreased and his fluid overload resolved . Administration of rFVIIa appears to have stabilized the coagulation process . The patient appears to have fully recovered from the infection's complications .

Int J Antimicrob Agents, 2004 Jul, 24(1), 48 - 52
In vitro activity of parenteral Beta-lactams, levofloxacin and tobramycin alone or in combination against extended-spectrum Beta-lactamase producing Klebsiella pneumoniae; Burgess DS et al.; MICs and time-kill studies were performed for four clinical isolates of extended-spectrum Beta-lactamase (ESBL)-producing Klebsiella pneumoniae . MICs (mg/L) were: piperacillin/tazobactam 8, cefepime 1-2, meropenem 0.03-0.06, levofloxacin 0.5-8 and tobramycin 0.25-32 . For monotherapy, only meropenem maintained bactericidal activity over the 24 h for all isolates . Levofloxacin and tobramycin maintained bactericidal activity against the isolate susceptible to each drug . Piperacillin/tazobactam and cefepime did not maintain bactericidal activity against any isolate . Combination therapy with piperacillin/tazobactam or cefepime combined with levofloxacin or tobramycin were able to provide dramatic killing against ESBL K . pneumoniae, but did not always maintain bactericidal activity . Future studies should evaluate different antimicrobial combinations against pathogens producing specific ESBL enzymes to define their utility as an alternative to carbapenems.

J Microbiol Immunol Infect, 2004 Jun, 37(3), 176 - 84
Comparison of pyogenic liver abscess caused by non-Klebsiella pneumoniae and Klebsiella pneumoniae; Yang CC et al.; From January 1996 to April 2002, a total of 248 patients with pyogenic liver abscess were enrolled in this study . Abscesses caused by Klebsiella pneumoniae accounted for 69% (171) of cases . Abscesses caused by K . pneumoniae were more strongly associated with diabetes mellitus or impaired fasting glucose than liver abscesses caused by non-K . pneumoniae (70.2% vs 32.5%) . Solitary abscess and monomicrobial isolates were more frequent in the K . pneumoniae group than that in the non-K . pneumoniae group . A total of 42 patients were treated with antibiotics alone . Antibiotics treatment was combined with other procedures, including single aspiration in 23 patients, percutaneous drainage in 176 and surgical drainage in 7 . A higher incidence of metastatic infections occurred in the K . pneumoniae group than in the non-K . pneumoniae group (14.6% vs 3.8%) . By contrast, the mortality rate of the K . pneumoniae group was lower than that of non-K . pneumoniae group (4.1% vs 20.8%) . There was no significant difference in the relapse rate between these 2 groups (6.5% vs 6.4%) . We also found that the presence of respiratory symptoms (including cough, dyspnea, or chest distress), size of abscess > or =5 cm in diameter and non-K . pneumoniae pathogens were significant prognostic factors for mortality.

Antimicrob Agents Chemother, 2004 Jul, 48(7), 2400 - 8
Diversity and evolution of the class A chromosomal beta-lactamase gene in Klebsiella pneumoniae; Haeggman S et al.; We investigated the diversity of the chromosomal class A beta-lactamase gene in Klebsiella pneumoniae in order to study the evolution of the gene . A 789-bp portion was sequenced in a panel of 28 strains, representative of three phylogenetic groups, KpI, KpII, and KpIII, recently identified in K . pneumoniae and of different chromosomal beta-lactamase variants previously identified . Three groups of sequences were found, two of them corresponding to the families SHV (pI 7.6) and LEN (pI 7.1), respectively, and one, more heterogeneous, corresponding to a new family that we named OKP (for other K . pneumoniae beta-lactamase) . Levels of susceptibility to ampicillin, cefuroxime, cefotaxime, ceftazidime, and aztreonam and inhibition by clavulanic acid were similar in the three groups . One new SHV variant, seven new LEN variants, and four OKP variants were identified . The OKP variants formed two subgroups based on nucleotide sequences, one with pIs of 7.8 and 8.1 and the other with pIs of 6.5 and 7.0 . The nucleotide sequences of the housekeeping genes gyrA, coding for subunit A of gyrase, and mdh, coding for malate dehydrogenase, were also determined . Phylogenetic analysis of the three genes studied revealed parallel evolution, with the SHV, OKP, and LEN beta-lactamase families corresponding to the phylogenetic groups KpI, KpII, and KpIII, respectively . This correspondence was fully confirmed for 34 additional strains in PCR assays specific for the three beta-lactamase families . We estimated the time since divergence of the phylogenetic groups KpI and KpIII at between 6 and 28 million years, confirming the ancient presence of the beta-lactamase gene in the genome of K . pneumoniae.

Infect Immun, 2004 Jul, 72(7), 3783 - 92
Isolation of a chromosomal region of Klebsiella pneumoniae associated with allantoin metabolism and liver infection; Chou HC et al.; Klebsiella pneumoniae liver abscess with metastatic complications is an emerging infectious disease in Taiwan . To identify genes associated with liver infection, we used a DNA microarray to compare the transcriptional profiles of three strains causing liver abscess and three strains not associated with liver infection . There were 13 clones that showed higher RNA expression levels in the three liver infection strains, and 3 of these 13 clones contained a region that was absent in MGH 78578 . Sequencing of the clones revealed the replacement of 149 bp of MGH 78578 with a 21,745-bp fragment in a liver infection strain, NTUH-K2044 . This 21,745-bp fragment contained 19 open reading frames, 14 of which were proven to be associated with allantoin metabolism . The K2044 (DeltaallS) mutant showed a significant decrease of virulence in intragastric inoculation of BALB/c mice, and the prevalence of this chromosomal region was significantly higher in strains associated with liver abscess than in those that were not (19 or 32 versus 2 of 94; P = 0.0001 {chi(2) test}) . Therefore, the 22-kb region may play a role in K . pneumoniae liver infection and serve as a marker for rapid identification.

J Immunol, 2004 Jul 1, 173(1), 559 - 65
Prostaglandin E2 inhibits alveolar macrophage phagocytosis through an E-prostanoid 2 receptor-mediated increase in intracellular cyclic AMP; Aronoff DM et al.; Prostaglandin E(2) is a potent lipid mediator of inflammation that effects changes in cell functions through ligation of four distinct G protein-coupled receptors (E-prostanoid (EP)1, EP2, EP3, and EP4) . During pneumonia, PGE(2) production is enhanced . In the present study, we sought to assess the effect of endogenously produced and exogenously added PGE(2) on FcRgamma-mediated phagocytosis of bacterial pathogens by alveolar macrophages (AMs), which are critical participants in lung innate immunity . We also sought to characterize the EP receptor signaling pathways responsible for these effects . PGE(2) (1-1000 nM) dose-dependently suppressed the phagocytosis by rat AMs of IgG-opsonized erythrocytes, immune serum-opsonized Klebsiella pneumoniae, and IgG-opsonized Escherichia coli . Conversely, phagocytosis was stimulated by pretreatment with the cyclooxygenase inhibitor indomethacin . PGE(2) suppression of phagocytosis was associated with enhanced intracellular cAMP production . Experiments using both forskolin (adenylate cyclase activator) and rolipram (phosphodiesterase IV inhibitor) confirmed the inhibitory effect of cAMP stimulation . Immunoblot analysis of rat AMs identified expression of only EP2 and EP3 receptors . The selective EP2 agonist butaprost, but neither the EP1/EP3 agonist sulprostone nor the EP4-selective agonist ONO-AE1-329, mimicked the effects of PGE(2) on phagocytosis and cAMP stimulation . Additionally, the EP2 antagonist AH-6809 abrogated the inhibitory effects of both PGE(2) and butaprost . We confirmed the specificity of our results by showing that AMs from EP2-deficient mice were resistant to the inhibitory effects of PGE(2) . Our data support a negative regulatory role for PGE(2) on the antimicrobial activity of AMs, which has important implications for future efforts to prevent and treat bacterial pneumonia.

Bioorg Med Chem, 2004 Jul 15, 12(14), 3847 - 55
Analogs of 1-phosphonooxy-2,2-dihydroxy-3-oxo-5-(methylthio)pentane, an acyclic intermediate in the methionine salvage pathway: a new preparation and characterization of activity with E1 enolase/phosphatase from Klebsiella oxytoca; Zhang Y et al.; The methionine salvage pathway allows the in vivo recovery of the methylthio moiety of methionine upon the formation of methylthioadenosine (MTA) from S-adenosylmethionine (SAM) . The Fe(II)-containing form of acireductone dioxygenase (ARD) catalyzes the penultimate step in the pathway in Klebsiella oxytoca, the oxidative cleavage of the acireductone 1,2-dihydroxy-3-oxo-5-(methylthio)pent-1-ene (2) by dioxygen to give formate and 2-oxo-4-(methylthio)butyrate (3) . The Ni(II)-bound form (Ni-ARD) catalyzes an off-pathway shunt, forming 3-(methylthio)propionate (4), carbon monoxide, and formate . Acireductone 2 is formed by the action of another enzyme, E1 enolase/phosphatase, on precursor 1-phosphonooxy-2,2-dihydroxy-3-oxo-5-methylthiopentane (1) . Simple syntheses of several analogs of 1 are described, and their activity as substrates for E1 enolase/phosphatase characterized . A new bacterial overexpression system and purification procedure for E1, a member of the haloacid dehalogenase (HAD) superfamily, is described, and further characterization of the enzyme presented.

Clin Infect Dis, 2004 Jul 1, 39(1), 55 - 60 Epub 2004 Jun 14.
Emergence of carbapenem-resistant Klebsiella species possessing the class A carbapenem-hydrolyzing KPC-2 and inhibitor-resistant TEM-30 beta-lactamases in New York City; Bradford PA et al.; Nineteen isolates of carbapenem-resistant Klebsiella species were recovered from 7 hospitals in New York City . Most K . pneumoniae belonged to a single ribotype . Nucleotide sequencing identified KPC-2, a carbapenem-hydrolyzing beta -lactamase . In 3 strains, TEM-30, an inhibitor-resistant beta -lactamase, was detected . Carbapenem-resistant Klebsiella species possessing KPC-2 are endemic in New York City . This study documents the identification of an inhibitor-resistant TEM beta -lactamase in the United States.

Clin Infect Dis, 2004 Jul 1, 39(1), 31 - 7 Epub 2004 Jun 08.
Antibiotic therapy for Klebsiella pneumoniae bacteremia: implications of production of extended-spectrum beta-lactamases; Paterson DL et al.; The prevalence of extended-spectrum beta -lactamase (ESBL) production by Klebsiella pneumonia approaches 50% in some countries, with particularly high rates in eastern Europe and Latin America . No randomized trials have ever been performed on treatment of bacteremia due to ESBL-producing organisms; existing data comes only from retrospective, single-institution studies . In a prospective study of 455 consecutive episodes of Klebsiella pneumoniae bacteremia in 12 hospitals in 7 countries, 85 episodes were due to an ESBL-producing organism . Failure to use an antibiotic active against ESBL-producing K . pneumoniae was associated with extremely high mortality . Use of a carbapenem (primarily imipenem) was associated with a significantly lower 14-day mortality than was use of other antibiotics active in vitro . Multivariate analysis including other predictors of mortality showed that use of a carbapenem during the 5-day period after onset of bacteremia due to an ESBL-producing organism was independently associated with lower mortality . Antibiotic choice is particularly important in seriously ill patients with infections due to ESBL-producing K . pneumoniae.

Exp Lung Res, 2004 Jun, 30(4), 251 - 60
Immunoglobulin M-enriched intravenous polyclonal immunoglobulins reduce bacteremia following Klebsiella pneumoniae infection in an acute respiratory distress syndrome rat model; Lachmann RA et al.; Mechanical ventilation is known to induce bacterial translocation from the lung into the systemic circulation . This study determined the effect of immunoglobulin M (IgM)-enriched polyclonal immunoglobulins on bacteremia due to ventilation-induced translocation in an acute respiratory distress syndrome (ARDS) rat model with Klebsiella-induced pneumonia . After whole lung lavage, Sprague-Dawley rats intravenously received either a high dose or a low dose of an immunoglobulin preparation, or an albumin solution as control, followed by an intratracheal injection of a Klebsiella pneumoniae solution . Blood colony-forming units (CFUs) in the treatment groups were significantly lower during the 3-hour ventilation period compared to the control group . The authors conclude that IgM-enriched polyclonal immunoglobulins lead to a reduction of bacteria in blood of surfactant-deficient, ventilated rats infected with Klebsiella pneumoniae.

J Antimicrob Chemother, 2004 Aug, 54(2), 406 - 9 Epub 2004 Jun 16.
A novel extended-spectrum beta-lactamase CTX-M-23 with a P167T substitution in the active-site omega loop associated with ceftazidime resistance; Sturenburg E et al.; OBJECTIVE: In recent years, cefotaximases of the CTX-M type have become a predominant cause of resistance to extended-spectrum cephalosporins in Gram-negative bacteria . Although most enzymes provide higher levels of resistance to cefotaxime than to ceftazidime, mutants with enhanced catalytic efficiency against ceftazidime have recently been described . This report identifies another ceftazidime-resistant mutant of the CTX-M class of enzymes . METHODS: Two ceftazidime-resistant strains, Escherichia coli IFI-1 and Klebsiella pneumoniae IFI-2, were isolated from a 46-year-old man during treatment of postoperative peritonitis with ceftazidime . Susceptibility testing, mating-out assays, isoelectric focusing as well as PCR and sequencing techniques were carried out to investigate the underlying mechanism of resistance . RESULTS: E . coli IFI-1 and K . pneumoniae IFI-2 exhibited a clavulanic acid-inhibited substrate profile that included extended-spectrum cephalosporins . Notably, both strains had up to a 32-fold higher level of resistance to ceftazidime than to cefotaxime . Further characterization revealed that a novel bla(CTX-M) gene encoding a beta-lactamase with a pI of 8.9 was implicated in this resistance: CTX-M-23 . Along with the substitutions D114N and S140A, CTX-M-23 differed from CTX-M-1, the most closely related enzyme, by a P167T replacement in the active-site omega loop, which has not previously been observed in other CTX-M enzymes . By analogy with what was observed with certain TEM/PSE/BPS-type beta-lactamases, the amino acid substitution in the omega loop may explain ceftazidime resistance, which has only rarely been reported for other CTX-M enzymes . CONCLUSION: The emergence of a new ceftazidime-resistant CTX-M-type mutant provides evidence that these enzymes are able to broaden their substrate spectrum towards ceftazidime, probably due to substitutions in the active-site omega loop.

J Vet Pharmacol Ther, 2004 Jun, 27(3), 155 - 62
Pharmacokinetics of ciprofloxacin after single intravenous and repeat oral administration to cats; Albarellos GA et al.; The pharmacokinetic properties of ciprofloxacin, a second-generation fluoroquinolone, were investigated in six cats after single intravenous and repeat oral administration at a dosage of 10 mg/kg b.i.d . Ciprofloxacin serum concentration was analyzed by microbiological assay using Klebsiella pneumoniae ATCC 10031 as microorganism test . Serum ciprofloxacin disposition was best fitted to a bicompartmental and a monocompartmental open models with first-order elimination after intravenous and oral dosing respectively . After intravenous administration, distribution was rapid (t(1/2(d)), 0.22 +/- 0.23 h) and wide as reflected by the steady-state volume of distribution of 3.85 +/- 1.34 L/kg . Furthermore, elimination was rapid with a plasma clearance of 0.64 +/- 0.28 L/h.kg and a t(1/2(el)) of 4.53 +/- 0.74 h . After repeat oral administration, absorption was rapid with a half-life of 0.23 +/- 0.22 h and T(max) of 1.30 +/- 0.67 h . However bioavailability was low (33 +/- 12%), the peak plasma concentration at steady-state was 1.26 +/- 0.67 microg/mL . Drug accumulation was not significant after seven oral administrations . When efficacy predictors were estimated ciprofloxacin showed a good profile against gram-negative bacteria when administered either intravenously or orally, although its efficacy against gram-positive microorganisms is lower.

Retina, 2004 Jun, 24(3), 383 - 90
A 10-year comparison of endogenous endophthalmitis outcomes: an east Asian experience with Klebsiella pneumoniae infection; Chen YJ et al.; PURPOSE: To evaluate the infection sources and causative organisms in cases of endogenous endophthalmitis and review the outcomes for patients with Klebsiella pneumoniae infection during a 10-year period . METHODS: All cases of endogenous endophthalmitis treated at one Taiwanese hospital from July 1992 to June 2002 were retrospectively reviewed (n = 74; 86 eyes) . The study was divided into two 5-year periods, with patients stratified into Group F or Group L according to onset date within the first or last of these periods, respectively . The outcomes of cases of K . pneumoniae infection in Group L (21 eyes) and Group F (32 eyes) were compared . RESULTS: The major source of infection (liver abscess) and the causative organism (K . pneumoniae) did not change throughout the 10-year review period; however, outcomes for Group L appeared superior . The interval from onset of ocular symptoms to ophthalmic consultation was shorter for Group L; however, a statistically significant difference was not demonstrated by between-group comparison . Patients with good final vision typically had good initial vision in cases of K . pneumoniae infection . CONCLUSION: The authors' experience with endogenous endophthalmitis has confirmed the findings of analogous East Asian studies, with liver abscess as the major source of infection and K . pneumoniae as the causative organism . Superior outcome may be achieved with more comprehensive and collaborative management, ideally through the combined efforts of multiple medical subspecialties.

J Clin Microbiol, 2004 Jun, 42(6), 2783 - 5
Clinical significance and mechanism of gas formation of pyogenic liver abscess due to Klebsiella pneumoniae; Lee HL et al.; We enrolled 22 patients with gas-forming pyogenic liver abscess in a study to assess the mechanism of gas formation . Klebsiella pneumoniae was cultured from specimens from all patients . Gas and pus samples from abscesses revealed four major components: nitrogen, oxygen, carbon dioxide, and hydrogen; this implicates mixed acid fermentation of glucose as the mechanism of gas formation.

J Clin Microbiol, 2004 Jun, 42(6), 2701 - 6
Detection and prevalence of active drug efflux mechanism in various multidrug-resistant Klebsiella pneumoniae strains from Turkey; Hasdemir UO et al.; The prevalence of active drug efflux pump and porin alterations was investigated in Turkish nosocomial strains of Klebsiella pneumoniae exhibiting a multidrug-resistant phenotype . MICs of various antibiotics, including quinolones, chloramphenicol, tetracycline, and beta-lactams, for those strains were determined either with or without the efflux pump inhibitor phenylalanine arginine beta-naphthylamide (PAbetaN) . Thirty-nine percent of the strains exhibited a PAbetaN-modulated resistance for quinolones, chloramphenicol, and tetracycline . In these strains, a significant increase of chloramphenicol accumulation was gained in the presence of the efflux pump inhibitor PAbetaN or with the energy uncoupler carbonyl cyanide m-chlorophenylhydrazone . Moreover, high-level expression of the membrane fusion protein AcrA, which was immunodetected in most of those isolates, suggests that the AcrAB/TolC efflux machinery contributed to their antibiotic resistance . Studies of K . pneumoniae porins indicated that the majority of the strains, including extended-spectrum beta-lactamase producers and efflux-positive ones, presented an alteration in their sorbitol-sensitive porin (OmpK35) expression . This is the first report showing the prominent role of active drug efflux in the antibiotic resistance of nosocomial K . pneumoniae strains from Turkey.

Carbohydr Res, 2004 Jun 1, 339(8), 1491 - 6
Structural and immunochemical relationship between the O-antigenic polysaccharides from the enteroaggregative Escherichia coli strain 396/C-1 and Escherichia coli O126; Larsson EA et al.; The structure of the O-antigen polysaccharide (PS) from the enteroaggregative Escherichia coli strain 396/C-1 has been determined . Sugar and methylation analyses together with 1H and 13C NMR spectroscopy were the main methods used . Inter-residue correlations were determined by 1H,1H-NOESY, 1H,13C-heteronuclear multiple-bond correlation and dipole-dipole cross-correlated relaxation experiments . The PS is composed of pentasaccharide repeating units with the following structure: {structure: see text} . Analysis of NMR data reveals that on average the PS consists of approximately 13 repeating units and indicates that the biological repeating unit contains an N-acetylglucosamine residue at its reducing end . This structure is different to that reported for the O-antigen polysaccharide from E . coli O126 . Monospecific anti-E . coli O126 rabbit serum from The International Escherichia and Klebsiella Centre did not distinguish between the E . coli strain 396/C-1 and the E . coli O126 reference strain, neither in slide agglutination nor in an indirect enzyme immunoassay . Subsequent successful serotyping of the E . coli strain 396/C-1 showed it to be E . coli O126:K+:H27 .

Blood, 2004 Sep 15, 104(6), 1778 - 83 Epub 2004 May 27.
Direct bacterial protein PAMP recognition by human NK cells involves TLRs and triggers alpha-defensin production; Chalifour A et al.; Although human CD56(+)CD3(-) natural killer (NK) cells participate in immune responses against microorganisms, their capacity to directly recognize and be activated by pathogens remains unclear . These cells encode members of the Toll-like receptor (TLR) family, involved in innate cell activation on recognition of pathogen-associated molecular patterns (PAMPs) . We therefore evaluated whether the 2 bacterial protein PAMPs, the outer membrane protein A from Klebsiella pneumoniae (KpOmpA) and flagellin, which signal through TLR2 and TLR5, respectively, may directly stimulate human NK cells . These proteins induce interferon-gamma (IFN-gamma) production by NK cells and synergize with interleukin-2 (IL-2) and proinflammatory cytokines in PAMP-induced activation . Similar results were obtained using CD56(+)CD3(+) (NKR-expressing) T cells . NK cells from TLR2(-/-) mice fail to respond to KpOmpA, demonstrating TLR involvement in this effect . Defensins are antimicrobial peptides expressed mainly by epithelial cells and neutrophils that disrupt the bacterial membrane, leading to pathogen death . We show that NK cells and NKR-expressing T cells constitutively express alpha-defensins and that KpOmpA and flagellin rapidly induce their release . These data demonstrate for the first time that highly purified NK cells directly recognize and respond to pathogen components through TLRs and evidence defensins as a novel and direct cytotoxic pathway involved in NK cell-mediated protection against microorganisms.

Int J Antimicrob Agents, 2004 Mar, 23(3), 262 - 7
A Klebsiella pneumoniae producing three kinds of class A beta-lactamases encoded by one single plasmid isolated from a patient in Huashan Hospital, Shanghai, China; Xiong Z et al.; A Klebsiella pneumoniae strain was isolated from a sputum specimen of a patient in the intensive care unit in 1999 in Shanghai Huashan Hospital, China . The isolate was confirmed as an extended-spectrum beta-lactamase (ESBL) producing strain by double-disk synergy test . The results of susceptibility test showed that it was resistant to most beta-lactams (including third generation cephalosporins) and non-beta-lactam antimicrobial agents . Transconjugants were obtained at a frequency of 10(-4) . A plasmid of about 60 kb was obtained from the transconjugant by plasmid extraction . Three major nitrocefin-hydrolysing bands with pIs of 5.4, 8.2 and 8.4, were shown in extracts of the transconjugant . Partial gene amplification products of bla(TEM), bla(SHV), and CTX-M-1 group gene were obtained from the isolate as well as its transconjugant . The entire bla(TEM), bla(SHV), and bla(CTX-M) in the transconjugant were amplified by PCR and the PCR products were cloned into a pHSG398 vector . Afterwards, the susceptibility of transformants and activities of beta-lactamases of transformants on antibiotics were tested . The PCR products were directly sequenced, analysed and identified as TEM-1, SHV-12, and CTX-M-3 genes . These results confirm that this strain of Klebsiella pneumoniae produces SHV-12, CTX-M-3 ESBLs and TEM-1 beta-lactamase, encoded by one single plasmid, which is responsible for the resistance of this strain to most beta-lactams.

J Antimicrob Chemother, 2004 Jul, 54(1), 69 - 75 Epub 2004 May 26.
Evolutionary mapping of the SHV beta-lactamase and evidence for two separate IS26-dependent blaSHV mobilization events from the Klebsiella pneumoniae chromosome; Ford PJ et al.; OBJECTIVES: To determine the most likely evolutionary pathway that has led to the development of extended-spectrum SHV derivatives, and to the mobilization of blaSHV . MATERIALS AND METHODS: Evolutionary mapping used a shortest-path analysis of aligned blaSHV variants, and other basic bioinformatic approaches, such as CLUSTAL W and Blast were employed . RESULTS: Two main branches of the blaSHV evolutionary tree were located; both are derived from variant blaSHV-1 alleles . Identical mutations, responsible for extended-spectrum SHV substrate profiles, have been selected independently in each branch . There is evidence for a pool of non-mobile blaSHV framework sequences . Analysis of the genome sequence of Klebsiella pneumoniae confirms the chromosomal origin of blaSHV, whose mobilization has occurred at least twice, once for each of the main evolutionary branches . Both these mobilization events have been catalysed by IS26 . Evolution of blaSHV to give common extended-spectrum variants is most likely to have occurred following mobilization . CONCLUSIONS: These data shed new light on the evolution and mobilization of blaSHV, and these observations may be useful in predicting what might happen in future, both for blaSHV, and for other beta-lactamase genes.

Bioorg Med Chem Lett, 2004 Jun 21, 14(12), 3103 - 7
Conformationally restricted analogs of deoxynegamycin; Raju B et al.; Deoxynegamycin (1b) is a protein synthesis inhibitor with activity against Gram-negative (GN) bacteria . A series of conformationally restricted analogs were synthesized to probe its bioactive conformation . Indeed, some of the constrained analogs were found to be equal or better than deoxynegamycin in protein synthesis assay (1b, IC(50)=8.2 microM; 44, IC(50)=6.6 microM; 35e(2), IC(50)=1 microM) . However, deoxynegamycin had the best in vitro whole cell antibacterial activity (Escherichia coli, MIC=4-16 microg/mL; Klebsiella pneumoniae, MIC=8 microg/mL) suggesting that other factors such as permeation may also be contributing to the overall whole cell activity . A new finding is that deoxynegamycin is efficacious in an E . coli murine septicemia model (ED(50)=4.8 mg/kg), providing further evidence of the favorable in vivo properties of this class of molecules.

J Biol Chem, 2004 Jul 23, 279(30), 31113 - 20 Epub 2004 May 17.
Alternating access and a pore-loop structure in the Na+-citrate transporter CitS of Klebsiella pneumoniae; Sobczak I et al.; CitS of Klebsiella pneumoniae is a secondary transporter that transports citrate in symport with 2 Na(+) ions . Reaction of Cys-398 and Cys-414, which are located in a cytoplasmic loop of the protein that is believed to be involved in catalysis, with thiol reagents resulted in significant inhibition of uptake activity . The reactivity of the two residues was determined in single Cys mutants in different catalytic states of the transporter and from both sides of the membrane . The single Cys mutants were shown to have the same transport stoichiometry as wild type CitS, but the C398S mutation was responsible for a 10-fold loss of affinity for Na(+) . Both cysteine residues were accessible from the periplasmic as well as from the cytoplasmic side of the membrane by the membrane-impermeable thiol reagent {2-(trimethylammonium)ethyl} methanethiosulfonate bromide (MTSET) suggesting that the residues are part of the translocation site . Binding of citrate to the outward facing binding site of the transporter resulted in partial protection against inactivation by N-ethylmaleimide, whereas binding to the inward facing binding site resulted in essentially complete protection . A 10-fold higher concentration of citrate was required at the cytoplasmic rather than at the periplasmic side of the membrane to promote protection . Only marginal effects of citrate binding were seen on reactivity with MTSET . Binding of Na(+) at the periplasmic side of the transporter protected both Cys-398 and Cys-414 against reaction with the thiol reagents, whereas binding at the cytoplasmic side was less effective and discriminated between Cys-398 and Cys-414 . A model is presented in which part of the cytoplasmic loop containing Cys-398 and Cys-414 folds back into the translocation pore as a pore-loop structure . The loop protrudes into the pore beyond the citrate-binding site that is situated at the membrane-cytoplasm interface.

Diagn Microbiol Infect Dis, 2004 May, 49(1), 41 - 6
In vitro killing of parenteral beta-lactams against standard and high inocula of extended-spectrum beta-lactamase and non-ESBL producing Klebsiella pneumoniae; Burgess DS et al.; Minimum inhibitory concentrations and time-kill curves were performed against 8 Klebsiella pneumoniae (4 non-extended-spectrum beta-lactamase{ESBL} and 4 ESBL) for piperacillin/tazobactam (40/5 microg/mL), cefepime (20 microg/mL), and meropenem (4 microg/mL) by using a standard and high inocula . Imipenem was evaluated only at the standard inoculum for the non-ESBL and ESBL isolates . Samples were withdrawn at 7 predetermined time-points over 24 hours and plated on trypticase soy agar plates . Minimum inhibitory concentrations were: piperacillin/tazobactam 4 to 8 microg/mL (ESBL and non-ESBL), cefepime 1 to 2 microg/mL (ESBL) and 0.06 to 0.125 microg/mL (non-ESBL), imipenem 0.125 to 0.25 microg/mL (ESBL and non-ESBL), and meropenem 0.03 to 0.06 microg/mL (ESBL and non-ESBL) . Each antibiotic reached and maintained bactericidal killing (> or =3 log killing) for 24 hours against all non-ESBL isolates for both the standard and high inoculum . Cefepime, imipenem, and meropenem showed the same bactericidal activity against each ESBL isolate at the standard inoculum, whereas piperacillin/tazobactam showed bactericidal killing against only 1 ESBL isolate . At the high inoculum, cefepime and piperacillin/tazobactam were unable to maintain bactericidal activity against any of the ESBL isolates . Only meropenem was able to maintain bactericidal killing over 24 hours against the ESBL isolates at the high inoculum . In summary, meropenem and imipenem maintained bactericidal activity against non-ESBL and ESBL K . pneumoniae irrespective of the inoculum size . While piperacillin/tazobactam and cefepime are bactericidal against non-ESBL K . pneumoniae, their activity against ESBL K . pneumoniae is limited and based on the size of the inoculum . Until more data are available, piperacillin/tazobactam and cefepime should not be used for the treatment of ESBL K . pneumoniae.

Comp Med, 2004 Apr, 54(2), 185 - 92
Antimicrobial therapies for pulmonary Klebsiella pneumoniae infection in B6D2F1/J mice immunocompromised by use of sublethal irradiation; Bentzel DE et al.; Klebsiella pneumoniae is a common cause of nosocomially acquired pneumonia in immunocompromised patients . Previously, we established a pneumonia model using Klebsiella pneumoniae in B6D2F1/J mice sublethally irradiated with 7-Gy 60Co gamma-radiation and inoculated intratracheally . In the study reported here, we investigated survival of mice following 10 days of antimicrobial therapy with ceftriaxone, gentamicin, gatifloxacin, and a ceftriaxone-gentamicin combination given once daily . Survival was significantly prolonged in response to all therapies . However, survival of mice was 95% when treated with the ceftriaxone-gentamicin combination followed by ceftriaxone alone (75%), and gatifloxacin (80%), whereas survival for controls was 0% . In addition, resistance to any of the treatments did not develop during the study . We conclude that an immunocompromised status does not alter the Infectious Disease Society of America's primary recommendation for treating community-acquired K . pneumoniae pneumonia using a third-generation cephalosporin, with or without an aminoglycoside.

J Eukaryot Microbiol, 2003 Jul-Aug, 50(4), 299 - 303
Catalase is the bacteria-derived detoxifying substance against paramecia-killing toxin in wheat grass powder infusion; Mizobuchi N et al.; Paramecium cells are usually cultured in a wheat grass powder infusion inoculated with Klebsiella pneumoniae . However, non-bacterized wheat grass powder infusion is toxic to paramecia, and bacteria-derived substance detoxifies the toxic substance . Here, the detoxifying substance from K . pneumoniae, which was found to be proteinaceous, was purified to homogeneity . The protein had an apparent molecular mass of about 200 kDa by gel filtration and 92 kDa by SDS-polyacrylamide gel electrophoresis . Although the amino acid sequence of the amino terminal region did not show a high sequence homology with any reported proteins, amino acid sequences of internal regions of the protein were nearly identical to catalase HPII from Escherichia coli . When the wheat grass powder infusion was treated at 25 degrees C for 1 h with commercially available catalase from bovine liver, the toxicity of the infusion against paramecia was completely abolished . The initial concentration of hydrogen peroxide in the wheat grass powder infusion was about 30 microM and was completely decomposed by the catalase treatment . Therefore, the toxic substance in the wheat grass powder infusion and the detoxifying substance from K . pneumoniae are considered as hydrogen peroxide and catalase, respectively.

Eur J Clin Microbiol Infect Dis, 2004 May, 23(5), 403 - 7 Epub 2004 Apr 27.
Four cases of necrotizing fasciitis caused by Klebsiella species; Wong CH et al.; Presented here are four cases of necrotizing fasciitis caused by Klebsiella spp . that were treated at one hospital over a 2-year period . Klebsiella necrotizing fasciitis can occur via direct inoculation, local trauma or, more commonly, hematogenous spread from other septic foci . Early, aggressive, surgical debridement and appropriate antimicrobial treatment are the cornerstones of treatment for this condition . Necrotizing fasciitis due to Klebsiella spp . is unique in that it is commonly associated with multiple septic foci . While liver abscesses and endogenous endophthalmitis are better-known associations of disseminated Klebsiella infection, necrotizing fasciitis is increasingly recognized as one of the manifestations of this syndrome . When treating Klebsiella necrotizing fasciitis, awareness of the potential for multiorgan involvement should prompt a thorough search for associated foci of infection.

FEBS Lett, 2004 Apr 30, 564(3), 340 - 8
An antibody library for stabilizing and crystallizing membrane proteins - selecting binders to the citrate carrier CitS; Rothlisberger D et al.; Co-crystallization of membrane proteins with antibody fragments may emerge as a general tool to facilitate crystal growth and improve crystal quality . The bound antibody fragment enlarges the hydrophilic part of the mostly hydrophobic membrane protein, thereby increasing the interaction area for possible protein-protein contacts in the crystal . Additionally, it may restrain flexible parts or lock the membrane protein in a defined conformational state . For successful co-crystallization trials, the antibody fragments must be stable in detergents during the extended period of crystal growth and must be easily produced in amounts necessary for crystallography . Therefore, we constructed a library of antibody Fab fragments from a framework subset of the HuCAL GOLD library (Morphosys, Munich, Germany) . By combining the most stable and well expressed frameworks, V(H)3 and V(kappa)3, with the further stabilizing constant domains, a Fab library with the desired properties was obtained in a standard phage display format . As a proof of principle, we selected binders with phage display against the detergent-solubilized citrate transporter CitS of Klebsiella pneumoniae . We describe efficient methods for the immobilization of the membrane protein during selection, for ELISA screening, and for BIAcore evaluation . We demonstrate that the selected Fab fragments form stable complexes with native CitS and recognize conformational epitopes with affinities in the low nanomolar range.

Antonie Van Leeuwenhoek, 2004 Jul, 86(1), 65 - 76
Factors influencing the replication of somatic coliphages in the water environment; Muniesa M et al.; The potential replication of somatic coliphages in the environment has been considered a drawback for their use as viral indicators, although the extent to which this affects their numbers in environmental samples has not been assessed . In this study, the replication of somatic coliphages in various conditions was assayed using suspensions containing naturally occurring somatic coliphages and Escherichia coli WG5, which is a host strain recommended for detecting somatic coliphages . The effects on phage replication of exposing strain WG5 and phages to a range of physiological conditions and the effects of the presence of suspended particles or other bacteria were also assayed . Phage replication was further tested using a strain of Klebsiella terrigena and naturally occurring E . coli cells as hosts . Our results indicate that threshold densities of both host bacterium and phages should occur simultaneously to ensure appreciable phage replication . Host cells originating from a culture in the exponential growth phase and incubation at 37 degrees C were the best conditions for phage replication in E . coli WG5 . In these conditions the threshold densities required to ensure phage replication were about 10(4) host cells/ml and 10(3) phages/ml, or 10(3) host cells/ml and 10(4) phages/ml, or intermediate values of both . The threshold densities needed for phage replication were higher when the cells proceeded from a culture in the stationary growth phase or when suspended particles or other bacteria were present . Furthermore E . coli WG5 was more efficient in supporting phage replication than either K . terrigenae or E . coli cells naturally occurring in sewage . Our results indicate that the phage and bacterium densities and the bacterial physiological conditions needed for phage replication are rarely expected to be found in the natural water environments.

J Biol Chem, 2004 Jul 2, 279(27), 28233 - 42 Epub 2004 Apr 21.
Siderophore peptide, a new type of post-translationally modified antibacterial peptide with potent activity; Thomas X et al.; Microcin E492 (MccE492, 7886 Da), the 84-amino acid antimicrobial peptide from Klebsiella pneumoniae, was purified in a post-translationally modified form, MccE492m (8717 Da), from culture supernatants of either the recombinant Escherichia coli VCS257 strain harboring the pJAM229 plasmid or the K . pneumoniae RYC492 strain . Chymotrypsin digestion of MccE492m led to the MccE492m-(74-84) C-terminal fragment that carries the modification and that was analyzed by mass spectrometry and nuclear magnetic resonance at natural abundance . The 831-Da post-translational modification consists of a trimer of N-(2,3-dihydroxybenzoyl)-l-serine linked via a C-glycosidic linkage to a beta-d-glucose moiety, itself linked to the MccE492m Ser-84-carboxyl through an O-glycosidic bond . This modification, which mimics a catechol-type siderophore, was shown to bind ferric ions by analysis of the collision-induced dissociation pattern obtained for MccE492m-(74-84) by electrospray ion trap mass spectrometry experiments in the presence of FeCl(3) . By using a series of wild-type and mutant isogenic strains, the three catechol-type siderophore receptors Fiu, Cir, and FepA were shown to be responsible for the recognition of MccE492m at the outer membrane of sensitive bacteria . Because MccE492m shows a broader spectrum of antibacterial activity and is more potent than MccE492, we propose that by increasing the microcin/receptor affinity, the modification leads to a better recognition and subsequently to a higher antimicrobial activity of the microcin . Therefore, MccE492m is the first member of a new class of antimicrobial peptides carrying a siderophore-like post-translational modification and showing potent activity, which we term siderophore-peptides.

Alcohol Clin Exp Res, 2004 Apr, 28(4), 635 - 42
Acute alcohol intoxication during hemorrhagic shock: impact on host defense from infection; Zambell KL et al.; BACKGROUND: Acute alcohol intoxication is a frequent underlying condition associated with traumatic injury . Our studies have demonstrated that acute alcohol intoxication significantly impairs the immediate hemodynamic, metabolic, and inflammatory responses to hemorrhagic shock . This study investigated whether acute alcohol intoxication during hemorrhagic shock would alter the outcome from an infectious challenge during the initial 24 hr recovery period . METHODS: Chronically catheterized male Sprague Dawley rats were randomized to acute alcohol intoxication (EtOH; 1.75 g/kg bolus followed by a constant 15 hr infusion at 250-300 mg/kg/hr) or isocaloric isovolemic dextrose infusion (dex; 3 ml + 0.375 ml/hr) . EtOH and dex were assigned to either fixed-volume (50%) hemorrhagic shock followed by fluid resuscitation with Ringer's lactate (EtOH/hem, dex/hem) or sham hemorrhagic shock (EtOH/sham, dex/sham) . Indexes of circulating neutrophil function (apoptosis, phagocytosis, oxidative burst) were obtained at baseline, at completion of hemorrhagic shock, and at the end of fluid resuscitation . Bacterial clearance, lung cytokine expression, and myeloperoxidase activity were determined at 6 and 18 hr after an intratracheal challenge with Klebsiella pneumoniae (10 colony-forming units) . RESULTS: Mean arterial blood pressure was significantly lower in acute alcohol intoxication-hemorrhagic shock animals throughout the hemorrhagic shock . In sham animals, acute alcohol intoxication alone did not produce significant changes in neutrophil apoptosis or phagocytic activity but significantly suppressed phorbol myristic acid (PMA)-stimulated oxidative burst . Hemorrhagic shock produced a modest increase in neutrophil apoptosis and suppression of neutrophil phagocytic capacity but significantly suppressed PMA-stimulated oxidative burst . Acute alcohol intoxication exacerbated the hemorrhagic shock-induced neutrophil apoptosis and the hemorrhagic shock-induced suppression of phagocytosis without further affecting PMA-stimulated oxidative burst . Fluid resuscitation did not restore neutrophil phagocytosis or oxidative burst . Acute alcohol intoxication decreased (-40%) 3-day survival from K . pneumoniae in hemorrhagic shock animals, impaired bacterial clearance during the first 18 hr postinfection, and prolonged lung proinflammatory cytokine expression . CONCLUSIONS: These results demonstrate that the early alterations in metabolic and inflammatory responses to hemorrhagic shock produced by acute alcohol intoxication are associated with neutrophil dysfunction and impaired host response to a secondary infectious challenge leading to increased morbidity and mortality.

Int J Antimicrob Agents, 2004 Apr, 23(4), 398 - 400
Klebsiella pneumoniae isolate from South Africa with multiple TEM, SHV and AmpC beta-lactamases; Essack SY et al.; Klebsiella pneumoniae 2207, from Durban, was resistant to cefoxitin and beta-lactamase inhibitor combinations as well as oxyimino-aminothiazolyl cephalosporins . Beta-lactamases with isoelectric points of 5.4, 5.6, 7.6, 8.2 and 8.4 were found . DNA hybridisation identified two BamHI and three HindIII fragments carrying blaTEM, and two SalI fragments carrying blaSHV . At least two genes encoded TEM-1 enzyme; one blaSHV copy encoded SHV-5 but the other determined SHV-23, a novel SHV-5 variant with conservative amino-acid substitutions far from the catalytic site . The pI 8.4 activity was an AmpC-type enzyme . Determinants of the pI 5.6 and 7.6 activities were not identified.

Diagn Microbiol Infect Dis, 2004 Apr, 48(4), 277 - 82
A pragmatic approach to identify extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in Taiwan: in vitro activity of newer and established antimicrobial agents; Yu WL et al.; The activities of 17 antimicrobials were evaluated against 211 clinical extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae isolates from Taiwan . A pragmatic approach by sequential Etest (AB BIODISK, Solna, Sweden) ESBL screen (narrow MIC range) and/or the usual Etest method (broad MIC range) was used . Among 131 isolates with a ceftazidime MIC of > 8 microg/ml, 125 (95.4%) had a reduction of > or =3 log2 dilution steps for ceftazidime (positive test) . Among 83 isolates with a ceftriaxone MIC of > 8 microg/ml and ceftazidime MIC at < or =8 microg/ml, 81 (97.5%) had a reduction of > or =3 three log2 dilution steps for ceftriaxone . Among the remaining eight isolates with nondeterminable results, additional Etest MIC method results revealed five ESBL-positive and two ESBL-negative (putative AmpC) determinations . This approach offered a cost-effective strategy to screen for ESBL among large number of isolates . The carbapenems (meropenem and imipenem) were the most active compounds (100% susceptibility) followed by newer fluoroquinolones (levofloxacin, gemifloxacin and gatifloxacin) at approximately 80% susceptible . Co-resistance to gentamicin was 96%, tobramycin 96%, and amikacin 62% . In conclusion, ESBL-producing strains of K . pneumoniae, also resistant to cefepime and aminoglycosides, are now widespread in Taiwan . The carbapenems and newer fluoroquinolones remain quite active against these ESBL strains recognized by this novel diagnostic approach.

Infect Control Hosp Epidemiol, 2004 Mar, 25(3), 221 - 5
Klebsiella pneumoniae bloodstream infections among neonates in a high-risk nursery in Cali, Colombia; Richards C et al.; OBJECTIVES: To determine the cause of an outbreak of Klebsiella pneumoniae bloodstream infections (BSIs) among neonates in a high-risk nursery and to institute control measures . DESIGN: During the on-site investigation, a cohort study to identify risk factors for K . pneumoniae BSI, a point-prevalence study to assess K . pneumoniae colonization, a maternal cohort study to determine maternal K . pneumoniae colonization, and an observational study to evaluate healthcare worker (HCW) compliance with infection control practices were conducted . PATIENTS AND SETTING: Neonates in a 40-bed high-risk nursery in a 700-bed university hospital in Cali, Colombia . INTERVENTION: Cohorting of neonates colonized with K . pneumoniae . RESULTS: The overall K . pneumoniae BSI attack rate was 10 of 105 (9.5%) . In the retrospective cohort study, the number of blood transfusions (OR, 3.1 per transfusion; P = .02; CI95, 1.4-9.7) and intravenous injections (OR, 1.2 per injection; P = .04; CI95, 1.0-1.5) were independently associated with K . pneumoniae BSI . The overall prevalence of K . pneumoniae colonization was 61% among neonates and 7% among mothers . During the HCW assessment, suboptimal intravenous therapy practices were observed . A cohorting intervention resulted in a significant reduction in K . pneumoniae colonization (12% vs 61%; RR, 0.19; P < .001) . During the intervention period, no K . pneumoniae BSIs occurred . CONCLUSIONS: This investigation suggested that the outbreak probably occurred due to widespread colonization and suboptimal infection control and intravenous therapy practices . Cohorting successfully reduced the overall prevalence of K . pneumoniae colonization and, along with improved infection control practices, probably prevented K . pneumoniae BSIs

Infect Control Hosp Epidemiol, 2004 Mar, 25(3), 210 - 5
Outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in a neonatal intensive care unit linked to artificial nails; Gupta A et al.; BACKGROUND: From April to June 2001, an outbreak of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae infections was investigated in our neonatal intensive care unit . METHODS: Cultures of the gastrointestinal tracts of patients, the hands of healthcare workers (HCWs), and the environment were performed to detect potential reservoirs for ESBL-producing K . pneumoniae . Strains of K . pneumoniae were typed by pulsed-field gel electrophoresis using XbaI . A case-control study was performed to determine risk factors for acquisition of the outbreak clone (clone A); cases were infants infected or colonized with clone A and controls (3 per case) were infants with negative surveillance cultures . RESULTS: During the study period, 19 case-infants, of whom 13 were detected by surveillance cultures, harbored clone A . The overall attack rate for the outbreak strain was 45%; 9 of 19 infants presented with invasive disease (n = 6) or developed invasive disease (n = 3) after colonization was detected . Clone A was found on the hands of 2 HCWs, 1 of whom wore artificial nails, and on the designated stethoscope of a case-infant . Multiple logistic regression analysis revealed that length of stay per day (odds ratio {OR}, 1.05; 95% confidence interval {CI95}, 1.02 to 1.09) and exposure to the HCW wearing artificial fingernails (OR, 7.87; CI95, 1.75 to 35.36) were associated with infection or colonization with clone A . CONCLUSION: Short, well-groomed, natural nails should be mandatory for HCWs with direct patient contact

Biochem Cell Biol, 2004 Apr, 82(2), 305 - 13
Low concentration of guanidine hydrochloride induces the formation of an aggregation-prone state in alpha-urease; McDuff FO et al.; Canavalia ensiformis (jack bean) alpha-urease is a hexameric protein characterized by a complex denaturation mechanism . In previous papers, we have shown that a hydrophobic 8-anilino-1-naphthalenesulfonic acid (ANSA) binding conformer could be populated in a moderate concentration of denaturant . This state was obtained under conditions that had no detectable impact on its tertiary structure, as indicated by fluorescence measurements . In the present study, we further characterized this ANSA-binding state in an attempt to understand urease behavior . Evidence presented here shows that the presence of ANSA was not required for the generation of the conformer and that its affinity for ANSA came from an increase in hydrophobicity leading to aggregation . Circular dichroism investigation of urease revealed that it had periodical secondary structure content similar to Klebsiella aerogenes urease (secondary structures calculated on the basis of crystallographic data) . The impact of 0.9 M guanidine hydrochloride (GuHCl) on soluble urease secondary structures was minimal but is compatible with a slight increase in beta-sheet structures . Such modification may indicates that aggregation involves amyloid-like fibril formation . Electron microscopy analysis of urease in the absence of GuHCl revealed the presence of urease hexamers (round shape 13 nm in diameter) . These particles disappeared in the presence of moderate denaturant concentration owing to the formation of aggregates and fibril-like structures . The fibrils obtained in 1.5 M GuHCl had an average diameter of 6.5 nm, suggesting that urease hexamers dissociated into smaller oligomeric forms when forming such fibrils.

Syst Appl Microbiol, 2004 Feb, 27(1), 27 - 35
Klebsiella variicola, a novel species with clinical and plant-associated isolates; Rosenblueth M et al.; A new Klebsiella species, K . variicola, is proposed on the basis of total DNA-DNA hybridization, on the monophyly observed in the phylogenetic analysis derived from the sequences of rpoB, gyrA, mdh, infB, phoE and nifH genes and on distinct phenotypic traits . The bacteria from this new species seem to be genetically isolated from K . pneumoniae strains, do not ferment adonitol and were obtained from plants (such as banana, rice, sugar cane and maize) and hospitals . The type strain is F2R9T (= ATCC BAA-830T = CFNE 2004T).

Biotechnol Lett, 2004 Feb, 26(3), 251 - 5
Cloning and sequence analysis of the dhaT gene of the 1,3-propanediol regulon from Klebsiella pneumoniae; Yuanyuan Z et al.; 1,3-Propanediol oxidoreductase encoded by dhaT gene, a gene of 1,3-propanediol regulon, is important in converting glycerol to 1,3-propanediol in Klebsiella pneumoniae . DhaT gene was amplified from the genome of K . pneumoniae, sequenced and its amino acid sequence deduced . A predicted secondary structure and 3D-structural model was constructed by homology modelling . Based on these results, we infer that 1,3-propanediol oxidoreductase belongs to NAD(P)-dependent alcohol dehydrogenase group III of iron-activated dehydrogenases.

Antimicrob Agents Chemother, 2004 Apr, 48(4), 1400 - 1
Activities of newer quinolones against Escherichia coli and Klebsiella pneumoniae containing the plasmid-mediated quinolone resistance determinant qnr; Wang M et al.; Seventeen qnr-containing transconjugants were constructed with azide-resistant Escherichia coli J53 as the recipient, and the MICs of 12 quinolones were tested by agar dilution methods . Sitafloxacin, BAYy3118, and premafloxacin had higher activity in vitro than ciprofloxacin against transconjugants and donors containing qnr . The donors had higher quinolone MICs than the transconjugants.

Antimicrob Agents Chemother, 2004 Apr, 48(4), 1295 - 9
Emerging plasmid-mediated quinolone resistance associated with the qnr gene in Klebsiella pneumoniae clinical isolates in the United States; Wang M et al.; Although quinolone resistance commonly results from chromosomal mutation, recent studies indicate that such resistance can also be transferred on plasmids carrying the gene responsible, qnr . One hundred ten ciprofloxacin-resistant clinical isolates of Klebsiella pneumoniae and Escherichia coli from the United States were screened for the qnr gene by PCR and Southern hybridization of plasmid DNA . Conjugation experiments were done with azide-resistant E . coli J53 as the recipient and selection with azide and sulfonamide, a resistance frequently linked to qnr . EcoRI and BamHI digests of qnr-hybridizing plasmids were subjected to electrophoresis on agarose gels and probed with qnr by Southern hybridization . qnr was detected in 8 (11.1%) of 72 K . pneumoniae strains . These eight positive strains were from six states in the United States . qnr was not found in any of the 38 E . coli strains tested . Quinolone resistance was transferred from seven of the eight probe-positive strains . Transconjugants with qnr-hybridizing plasmids had 32-fold increases in ciprofloxacin MICs relative to E . coli J53 . For all eight strains, the sequence of qnr was identical to that originally reported . By size and restriction digests, four plasmids were related to the first-reported plasmid, pMG252, and three were different . Five new qnr plasmids encoded FOX-5 beta-lactamase, as did pMG252, but two others produced SHV-7 extended-spectrum beta-lactamase . Transferable plasmid-mediated quinolone resistance associated with qnr is now widely distributed in quinolone-resistant clinical strains of K . pneumoniae in the United States . Plasmid-determined quinolone resistance contributes to the increasing quinolone resistance of K . pneumoniae isolates and to the linkage previously observed between resistance to quinolones and the latest beta-lactam antibiotics.

Antimicrob Agents Chemother, 2004 Apr, 48(4), 1204 - 14
Ambler class A extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella spp . in Canadian hospitals; Mulvey MR et al.; This report describes a study carried out to gain baseline information on the molecular characteristics of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella spp . in Canada . A total of 29,323 E . coli and 5,156 Klebsiella sp . isolates were screened at 12 participating sites . Of these, 505 clinically significant, nonrepeat isolates displaying reduced susceptibility to the NCCLS-recommended beta-lactams were submitted to a central laboratory over a 1-year period ending on 30 September 2000 . A total of 116 isolates were confirmed to be ESBL producers . PCR and sequence analysis revealed the presence of TEM-11 (n = 1), TEM-12 (n = 1), TEM-29 (n = 1), TEM-52 (n = 4), CTX-M-13 (n = 1), CTX-M-14 (n = 15), CTX-M-15 (n = 11), SHV-2 (n = 2), SHV-2a (n = 12), SHV-5 (n = 6), SHV-12 (n = 45), and SHV-30 (n = 2) . Five novel beta-lactamases were identified and designated TEM-115 (n = 2), TEM-120 (n = 1), SHV-40 (n = 2), SHV-41 (n = 4), and SHV-42 (n = 1) . In addition, no molecular mechanism was identified for five isolates displaying an ESBL phenotype . Macrorestriction analysis of all ESBL isolates was conducted, as was restriction fragment length polymorphism analysis of plasmids harboring ESBLs . Although a "clonal" distribution of isolates was observed at some individual sites, there was very little evidence suggesting intrahospital spread . In addition, examples of identical or closely related plasmids that were identified at geographically distinct sites across Canada are given . However, there was considerable diversity with respect to plasmid types observed.

Cancer, 2004 Apr 1, 100(7), 1531 - 6
Strongyloidiasis in patients at a comprehensive cancer center in the United States; Safdar A et al.; BACKGROUND: The frequency of Strongyloides stercoralis infestation and complication in patients with cancer in the United States is unknown . METHODS: The authors performed a retrospective analysis of S . stercoralis infection in patients who were undergoing cancer treatment at The University of Texas M . D . Anderson Cancer Center (Houston, TX) . RESULTS: The overall S . stercoralis infection frequency was approximately 1.0 per 10,000 new cancer cases between 1971 and 2003 . Twenty-two of 25 patients (88%) were U.S . residents (19 from Texas; 1 each from Mississippi, Tennessee, and Puerto Rico), and the remaining 3 (13%) were from Latin America . Thirteen (52%) had solid-organ malignancies, whereas 12 (48%) had hematologic malignancies (lymphoma or multiple myeloma, n=8; leukemia, n=3; aplastic anemia, n=1) . Twelve patients (48%) received systemic corticosteroids, 9 (36%) received antineoplastic therapy, and 2 underwent hematopoietic stem cell transplantation (HSCT) . Diarrhea was reported in 13 patients (57%), and eosinophilia was observed in 11 patients (48%); 4 patients (16%) had probable hyperinfection syndrome (in 3 cases of polymicrobial gram-negative bacteremia, 1 patient had Klebsiella pneumoniae pneumonia, whereas 1 patient presented with K . pneumoniae lung infection alone) . Evidence of definite pulmonary hyperinfection syndrome was observed in 2 HSCT recipients (8%) . Fourteen (74%) of 19 patients responded to thiabendazole therapy . Two patients with definite pulmonary hyperinfection syndrome developed fatal S . stercoralis hemorrhagic alveolitis despite receiving high-dose thiabendazole plus ivermectin therapy . CONCLUSIONS: In the current study, strongyloidiasis was uncommon in patients with cancer and remained localized in individuals with solid-organ malignancies . Definite pulmonary accelerated autoinfections were observed only in HSCT recipients . Therefore, pre-HSCT S . stercoralis screening in individuals from endemic regions of the United States warrants further study .

Vaccine, 2004 Feb 17, 22(7), 818 - 21
O antigen seroepidemiology of Klebsiella clinical isolates and implications for immunoprophylaxis of Klebsiella infections; Trautmann M et al.; Prevention of Klebsiella infections by passive immunotherapy has received more attention during the last decade . Both K antigen-and O antigen-specific antisera and monoclonal antibodies (mAbs) have been studied with respect to phagocytosis-enhancing and in vivo protective capacities . Our own work has focussed on the generation of O serogroup-specific rabbit antisera and O antigen specific murine antibodies . O-specific rabbit sera were absorbed extensively with heterologous O antigen strains in order to obtain highly specific typing reagents . Using these for typing a collection of 378 clinical strains, we found that 82% of them belonged to one of the four serogroups O1, O2ab, O3 and O5 . Phagocytosis experiments using antisera and mAbs showed that O antigen specific antibodies were able to opsonize non-encapsulated strains, while fully encapsulated bacteria were rather resistant against the opsonizing effect . Nevertheless, in vivo experiments demonstrated a prophylactic effect on both Klebsiella septicemia and pneumonia in a mouse model of lethal infection . Given the limited number of O serogroups, O antigen-specific antibodies may be suited to supplement K antigen-specific hyperimmune globulins for passive immunoprophylaxis of Klebsiella infections.

Presse Med, 2004 Jan 31, 33(2), 98 - 100
{Hepatic abscess in diabetics, 2 case reports}; Saad F et al.; INTRODUCTION: Over the past few years, the hepatic abscess appears as a privileged septic localisation in the case of diabetes mellitus, particularly in the elderly . OBSERVATIONS: Two, 75 year-old and 82 year-old, diabetic patients were hospitalised for non-ketonic decompensation of type 2 diabetes mellitus . Examination revealed a sub-febrile state, the absence of clinical hepatic signs and a biological infectious syndrome The abscesses were discovered during the systematic hepatic sonography . Liver puncture was only possible in one patient and revealed Klebsiella oxytoca . The progression with antibiotics alone in one patient, and associated with surgical draining in the other, was positive . The origin appeared to be bilary in one patient and arterial on the other . COMMENTS: These case reports underline the interest of the systematic evocation of an abscessed hepatic localisation in cases of imbalance in diabetes, particularly when associated with an unexplained infectious syndrome.

Int J Antimicrob Agents, 2004 Feb, 23(2), 150 - 4
Immunomodulating effect of antimicrobial agents on cytokine production by human polymorphonuclear neutrophils; Reato G et al.; It has been previously demonstrated that some antimicrobial agents enhance activities of human polymorphonuclear neutrophils (PMNs) . The effect on the release of cytokines in an inflammatory context from PMNs by these antibiotics was evaluated . We studied the effect of the release of some cytokines by human PMNs RT-PCR analysis on a clinical strain of Klebsiella pneumoniae by comparing the effect with that observed in the presence of co-amoxiclav, sanfetrinem, clarithromycin, prulifloxacin and tobramycin . All the drugs tested were capable of modulating PMN synthesis in vitro of pro-inflammatory cytokines IL-8, IL-1beta, TNF-alpha and IL-6, but not that of anti-inflammatory cytokine IL-10 . The degree of their stimulatory or inhibitory potency varied with the cytokine examined.

J Clin Microbiol, 2004 Mar, 42(3), 1337 - 40
Rapid detection of Klebsiella pneumoniae from blood culture bottles by real-time PCR; Kurupati P et al.; A LightCycler real-time PCR hybridization probe-based assay which detects a partial Klebsiella pneumoniae 16S rRNA gene was developed for the rapid identification of K . pneumoniae directly from growth-positive blood culture bottles (BACTEC 9240 system) within 2 h . No cross-reactivity was observed with 65 negative-control blood cultures that grew bacteria other than K . pneumoniae and 48 negative blood cultures from double-blind experiments, thus demonstrating 100% specificity when compared to results of conventional biochemical characterization . The assay also showed 100% sensitivity, as it correctly identified all 142 positive-control blood cultures and 4 from double-blind trials.

J Gravit Physiol, 2002 Jul, 9(1), P199 - 200
Stress, suspension and resistance to infection; Sonnenfeld G et al.; Immune function is altered in stressful situations, including space flight . This may result in increased risk of infection . Antiorthostatic suspension has been used to study the effects of space flight-like conditions on immunity . The mechanisms of promoting infection in stressful situations have not been defined, but catecholamines could play a role . In the present study gram negative bacteria grown with catecholamines showed enhanced bacterial growth compared to controls . Additionally, antiorthostatically suspended mice infected with Klebsiella pneumoniae showed decreased survival compared to restrained or normally caged controls . Therefore, stress-induced enhanced bacterial growth and immunosuppression could play a role in suspension-induced enhanced mortality due to infection.

J Mol Biol, 2004 Mar 12, 337(1), 77 - 92
Protelomerase uses a topoisomerase IB/Y-recombinase type mechanism to generate DNA hairpin ends; Huang WM et al.; Protelomerases are enzymes responsible for the generation of closed hairpin ends in linear DNA . It is proposed that they use a breaking-and-rejoin type mechanism to affect DNA rearrangement on specific DNA sequences . In doing so, one strand turns around and becomes the complementary strand . Using the purified enzyme from the Escherichia coli phage N15 and the Klebsiella phage phiKO2 and synthetic oligonucleotide substrates, we directly demonstrate the location where the cutting/re-ligation occurs . We identified a pair of transient staggered cleavages six base-pairs apart centered around the axis of dyad symmetry of the target site . Two molecules of the protelomerase form a pair of protein-linked DNA intermediates at each 3' end of the cleaved openings leaving a 5'-OH . Then, in a process not yet clearly defined, the partners of the two initial openings are exchanged, and the transient breaks are resealed to generate hairpin ends . The formation of 3'-covalent DNA-protein intermediates is a hallmark of the topoisomerase IB type reaction, and we have thus shown experimentally that protelomerase is a member of the tyrosine-recombinase superfamily . In addition, by introducing single nicks in the substrates as perturbation, we found that the integrity of the nucleotide chain 4 bp away from the cutting site as well as this nucleotide's complementary location on the stem if the strands were to fold into a cruciform structure are required for activity, suggesting that these locations may be important substrate-protein contacts . We determined that N15 and phiKO2 protelomerases are monomers in solution and two molecules are needed to interact with the substrate to form two closed hairpin products . The target sites of protelomerases invariably consist of inverted repeats . Comparative studies using the related target sites of different protelomerases suggest that these proteins may require both sequence-specific and structure (possibly cruciform)-specific recognition for activity.

J Bacteriol, 2004 Mar, 186(6), 1818 - 32
The pKO2 linear plasmid prophage of Klebsiella oxytoca; Casjens SR et al.; Temperate bacteriophages with plasmid prophages are uncommon in nature, and of these only phages N15 and PY54 are known to have a linear plasmid prophage with closed hairpin telomeres . We report here the complete nucleotide sequence of the 51,601-bp Klebsiella oxytoca linear plasmid pKO2, and we demonstrate experimentally that it is also a prophage . We call this bacteriophage phiKO2 . An analysis of the 64 predicted phiKO2 genes indicate that it is a fairly close relative of phage N15; they share a mosaic relationship that is typical of different members of double-stranded DNA tailed-phage groups . Although the head, tail shaft, and lysis genes are not recognizably homologous between these phages, other genes such as the plasmid partitioning, replicase, prophage repressor, and protelomerase genes (and their putative targets) are so similar that we predict that they must have nearly identical DNA binding specificities . The phiKO2 virion is unusual in that its phage lambda-like tails have an exceptionally long (3,433 amino acids) central tip tail fiber protein . The phiKO2 genome also carries putative homologues of bacterial dinI and umuD genes, both of which are involved in the host SOS response . We show that these divergently transcribed genes are regulated by LexA protein binding to a single target site that overlaps both promoters.

J Exp Med, 2004 Mar 1, 199(5), 697 - 705
A novel virulence gene in Klebsiella pneumoniae strains causing primary liver abscess and septic metastatic complications; Fang CT et al.; Primary Klebsiella pneumoniae liver abscess complicated with metastatic meningitis or endophthalmitis is a globally emerging infectious disease . Its pathogenic mechanism remains unclear . The bacterial virulence factors were explored by comparing clinical isolates . Differences in mucoviscosity were observed between strains that caused primary liver abscess (invasive) and those that did not (noninvasive) . Hypermucoviscosity correlated with a high serum resistance and was more prevalent in invasive strains (52/53 vs . 9/52; P < 0.0001) . Transposon mutagenesis identified candidate virulence genes . A novel 1.2-kb locus, magA, which encoded a 43-kD outer membrane protein, was significantly more prevalent in invasive strains (52/53 vs . 14/52; P < 0.0001) . The wild-type strain produced a mucoviscous exopolysaccharide web, actively proliferated in nonimmune human serum, resisted phagocytosis, and caused liver microabscess and meningitis in mice . However, magA- mutants lost the exopolysaccharide web and became extremely serum sensitive, phagocytosis susceptible, and avirulent to mice . Virulence was restored by complementation using a magA-containing plasmid . We conclude that magA fits molecular Koch's postulates as a virulence gene . Thus, this locus can be used as a marker for the rapid diagnosis and for tracing the source of this emerging infectious disease.

Arch Environ Health, 2003 Jun, 58(6), 337 - 47
Indoor air pollutants and immune biomarkers among Hungarian asthmatic children; Erdei E et al.; The authors examined the relationship between immune biomarkers and indoor air pollution cross-sectionally in school children 9-11 yr of age who had immunologically related respiratory diseases and who resided in Hungarian cities . Nitrogen dioxide, formaldehyde, benzene, xylene, and toluene were measured passively indoors prior to the collection of venous blood samples for blood counts and identification of immune biomarkers . House dust mite allergen was also measured . Numerous immune biomarkers were significantly elevated in these sensitive children, compared with normal children, and several biomarker alterations in these children were related to high concentrations of air pollutants in the home . The strongest and most significant associations were seen between high indoor nitrogen dioxide concentrations and increased white blood cells, monocytes, red blood cells, and immunoglobulin G (IgG), as well as decreased immunoglobulin M (IgM) and Klebsiella pneumoniae-specific IgM . Bacterial-specific IgGs were related significantly to formaldehyde concentrations . These findings suggest the important role of indoor air pollutants in immune reactions.

J Antimicrob Chemother, 2004 Apr, 53(4), 616 - 9 Epub 2004 Feb 25.
Post-antibiotic and post-beta-lactamase inhibitor effects of ceftazidime plus sulbactam on extended-spectrum beta-lactamase-producing Gram-negative bacteria; Lavigne JP et al.; OBJECTIVES: To measure the in vitro post-antibiotic effect (PAE) and post-beta-lactamase inhibitor effect (PLIE) of a ceftazidime-sulbactam combination on bacteria producing extended-spectrum beta-lactamases (ESBLs) . METHODS: PAE and PLIE were studied for ESBL-producing strains of Escherichia coli and Klebsiella pneumoniae . Two ATCC beta-lactamase-negative strains of E . coli and K . pneumoniae were used as controls . The MICs of a ceftazidime-sulbactam combination were determined with a fixed concentration of sulbactam (8 mg/L) . The organisms were exposed to the antibiotics at twice the MIC for 2 h before removal of the antibiotics by filtration of the culture . Bacteria on the filter were resuspended in drug-free medium to determine the PAE and in medium containing ceftazidime, at the same concentration as originally present, to determine the PLIE . RESULTS: The PAE of ceftazidime was similar for bacteria producing the same ESBL except for E . coli producing CTX-M-1 . PLIE values varied according to the type of beta-lactamase but similar results were observed for the strains producing the same ESBLs . PLIEs were longer than PAEs and were longer when the MICs of ceftazidime were lower . CONCLUSIONS: To the best of our knowledge, we describe here for the first time an in vitro PLIE for a ceftazidime-sulbactam combination on different bacteria producing different ESBLs . These findings indicate that suicide inhibitors may be used in combination with third-generation cephalosporins.

J Trop Pediatr, 2004 Feb, 50(1), 26 - 31
Antibiotic resistance patterns in nosocomial gram-negative bacterial infections in units with heavy antibiotic usage; Ariffin H et al.; The pattern of antibiotic resistance amongst gram-negative bacteria (GNB) in paediatric units, which have heavy empirical usage of broad-spectrum antibiotics, was studied prospectively over a 6-month period . A total of 200 consecutive, non-duplicate gram-negative isolates were obtained from 109 patients admitted to intensive care and oncology units in two hospitals . The commonest isolates were Klebsiella spp (36.5 per cent) and Pseudomonas (20.0 per cent) . The isolates showed lower susceptibility rates to the third-generation cephalosporins (47-62 per cent) compared with cefepime (91 per cent), imipenem (90 per cent) and ciprofloxacin (99 per cent) . Fifty-four (52.8 per cent) Klebsiella and Escherichia coli isolates were determined to be extended-spectrum beta-lactamase (ESBL) producing strains . Antibiotics found to be effective against ESBL-producers were imipenem and ciprofloxacin . The high resistance rate amongst GNB to third-generation cephalosporins is a likely consequence of heavy empirical usage of this group of antibiotics . The carbapenems and quinolones remain useful agents in the management of patients admitted to these units.

Infect Immun, 2004 Mar, 72(3), 1767 - 74
C3 promotes clearance of Klebsiella pneumoniae by A549 epithelial cells; de Astorza B et al.; The airway epithelium represents a primary site for contact between microbes and their hosts . To assess the role of complement in this event, we studied the interaction between the A549 cell line derived from human alveolar epithelial cells and a major nosocomial pathogen, Klebsiella pneumoniae, in the presence of serum . In vitro, we found that C3 opsonization of poorly encapsulated K . pneumoniae clinical isolates and an unencapsulated mutant enhanced dramatically bacterial internalization by A549 epithelial cells compared to highly encapsulated clinical isolates . Local complement components (either present in the human bronchoalveolar lavage or produced by A549 epithelial cells) were sufficient to opsonize K . pneumoniae . CD46 could competitively inhibit the internalization of K . pneumoniae by the epithelial cells, suggesting that CD46 is a receptor for the binding of complement-opsonized K . pneumoniae to these cells . We observed that poorly encapsulated strains appeared into the alveolar epithelial cells in vivo but that (by contrast) they were completely avirulent in a mouse model of pneumonia compared to the highly encapsulated strains . Our results show that bacterial opsonization by complement enhances the internalization of the avirulent microorganisms by nonphagocytic cells such as A549 epithelial cells and allows an efficient innate defense.

Infect Immun, 2004 Mar, 72(3), 1423 - 30
The Klebsiella pneumoniae O antigen contributes to bacteremia and lethality during murine pneumonia; Shankar-Sinha S et al.; Bacterial surface carbohydrates are important pathogenic factors in gram-negative pneumonia infections . Among these factors, O antigen has been reported to protect pathogens against complement-mediated killing . To examine further the role of O antigen, we insertionally inactivated the gene encoding a galactosyltransferase necessary for serotype O1 O-antigen synthesis (wbbO) from Klebsiella pneumoniae 43816 . Analysis of the mutant lipopolysaccharide by sodium dodecyl sulfate-polyacrylamide gel electrophoresis confirmed the absence of O antigen . In vitro, there were no detectable differences between wild-type K . pneumoniae and the O-antigen-deficient mutant in regard to avid binding by murine complement C3 or resistance to serum- or whole-blood-mediated killing . Nevertheless, the 72-h 50% lethal dose of the wild-type strain was 30-fold greater than that of the mutant (2 x 10(3) versus 6 x 10(4) CFU) after intratracheal injection in ICR strain mice . Despite being less lethal, the mutant organism exhibited comparable intrapulmonary proliferation at 24 h compared to the level of the wild type . Whole-lung chemokine expression (CCL3 and CXCL2) and bronchoalveolar inflammatory cell content were also similar between the two infections . However, whereas the wild-type organism produced bacteremia within 24 h of infection in every instance, bacteremia was not seen in mutant-infected mice . These results suggest that during murine pneumonia caused by K . pneumoniae, O antigen contributes to lethality by increasing the propensity for bacteremia and not by significantly changing the early course of intrapulmonary infection.

Folia Microbiol (Praha), 2003, 48(5), 699 - 702
Contribution of capsular and lipopolysaccharide antigens to the pathogenesis of Klebsiella pneumoniae respiratory tract infection; Chhibber S et al.; The role of Klebsiella pneumoniae K- and O-polysaccharide antigens was determined in a rat model of lobar pneumonia . The induction of experimental infection in rats by wild-type strain, and its lipopolysaccharide- and capsular polysaccharide-deficient mutants was compared . Though the mutant lacking both antigens (K- O-) induced infection it could not successfully establish itself in the rat lung . It caused only mild infection, as compared to the wild type strain (K+ O+) and the strain lacking CPS alone (K- O+) . Besides capsular polysaccharide, the lipopolysaccharide antigen was shown to be an important factor in pathogenesis of K . pneumoniae acute respiratory tract infection.

Folia Microbiol (Praha), 2003, 48(5), 665 - 9
Establishment of a sepsis model following implantation of Klebsiella pneumoniae-infected fibrin clot into the peritoneal cavity of mice; Toky V et al.; Successful establishment of sepsis by entrapping a dose of 150 colony forming units of Klebsiella pneumoniae in a fibrin clot following implantation into the peritoneal cavity of mice is reported . The dose in the fibrin clot gave 50% mortality in mice, spread over a period of one week . All the infected mice showed positive blood culture up to 6 d post-infection; histopathology revealed inflammatory changes in both liver and spleen . Introduction of K . pneumoniae into experimental mice without entrapment in fibrin clot caused no mortality and blood culture remained positive only up to 2 d; histopathology of liver and spleen throughout the period of study showed relatively mild inflammatory changes, which almost cleared during 14 d post-infection . The use of the fibrin-clot model may thus be considered to be useful in studying both the initial and the persisting stage of infection in the peritoneum, whence a slow release of bacteria into the blood takes place which finally leads to sepsis and septicemia.

J Biol Chem, 2004 Apr 30, 279(18), 18377 - 83 Epub 2004 Feb 17.
The Escherichia coli NADH:ubiquinone oxidoreductase (complex I) is a primary proton pump but may be capable of secondary sodium antiport; Stolpe S et al.; The NADH:ubiquinone oxidoreductase (complex I) couples the transfer of electrons from NADH to ubiquinone with the translocation of protons across the membrane . Recently, it was demonstrated that complex I from Klebsiella pneumoniae translocates sodium ions instead of protons . Experimental evidence suggested that complex I from the close relative Escherichia coli works as a primary sodium pump as well . However, data obtained with whole cells showed the presence of an NADH-induced electrochemical proton gradient . In addition, Fourier transform IR spectroscopy demonstrated that the redox reaction of the E . coli complex I is coupled to a protonation of amino acids . To resolve this contradiction we measured the properties of isolated E . coli complex I reconstituted in phospholipids . We found that the NADH:ubiquinone oxidoreductase activity did not depend on the sodium concentration . The redox reaction of the complex in proteoliposomes caused a membrane potential due to an electrochemical proton gradient as measured with fluorescent probes . The signals were sensitive to the protonophore carbonyl cyanide m-chlorophenylhydrazone (CCCP), the inhibitors piericidin A, dicyclohexylcarbodi-imide (DCCD), and amiloride derivatives, but were insensitive to the sodium ionophore ETH-157 . Furthermore, monensin acting as a Na(+)/H(+) exchanger prevented the generation of a proton gradient . Thus, our data demonstrated that the E . coli complex I is a primary electrogenic proton pump . However, the magnitude of the pH gradient depended on the sodium concentration . The capability of complex I for secondary Na(+)/H(+) antiport is discussed.

J Biomed Sci, 2004 Mar-Apr, 11(2), 152 - 62
N-acetylcysteine ameliorates lipopolysaccharide-induced organ damage in conscious rats; Hsu BG et al.; Lipopolysaccharide is strongly associated with septic shock, leading to multiple organ failure . It can activate monocytes and macrophages to release proinflammatory mediators such as tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and nitric oxide (NO) . The present experiments were designed to induce endotoxin shock by an intravenous injection of Klebsiella pneumoniae lipopolysaccharide (LPS, 10 mg/kg) in conscious rats . Arterial pressure and heart rate (HR) were continuously monitored for 48 h after LPS administration . N-Acetylcysteine was used to study its effects on organ damage . Biochemical substances were measured to reflect organ functions . Biochemical factors included blood urea nitrogen (BUN), creatinine (Cre), lactic dehydrogenase (LDH), creatine phosphokinase (CPK), aspartate transferase (GOT), alanine transferase (GPT), TNF-alpha, IL-1 beta, methyl guanidine (MG), and nitrites/nitrates . LPS caused significant increases in blood BUN, Cre, LDH, CPK, GOT, GPT, TNF-alpha, IL-1 beta, MG levels, and HR, as well as a decrease in mean arterial pressure and an elevation of nitrites/nitrates . N-Acetylcysteine suppressed the release of TNF-alpha, IL-1 beta, and MG, but enhanced NO production . These actions ameliorate LPS-induced organ damage in conscious rats . The beneficial effects may suggest a potential chemopreventive effect of this compound in sepsis prevention and treatment .

Acta Paediatr Taiwan, 2003 Sep-Oct, 44(5), 282 - 6
Liver abscess in children: a single institutional experience in southern Taiwan; Tsai CC et al.; Liver abscess is uncommon in children . The purpose of this study is to evaluate the predisposing factors, pathogens, duration of hospitalization, and the managements of liver abscess in children . From 1986 to 2001, fifteen children were admitted to our hospital under the diagnosis of liver abscess . Thirteen cases were older than 8 years old and two were younger than one year old . Fever (15/15, 100%) and abdominal pain (13/15, 87%) were the most common symptoms . Twelve patients (80%) had prolonged fever (fever for 7 days or longer before diagnosis) . Eleven (73%) cases were cryptogenic in origin . Most of the microorganisms were obtained solely from cultures of pus . Klebsiella pneumoniae was the most common organism isolated (6/15, 40%) . Beside administration of antibiotics, percutaneous catheter drainage (PCD) was performed in 11 patients (73%); only one underwent surgical intervention due to poor response to PCD management . All of our patients were surviving after at least one year follow-up . In conclusion, liver abscess should be suspected in the patients with prolonged fever of unknown origin and abdominal pain . PCD combined with adequate antibiotics were sufficient for therapy of liver abscess in most cases . K . pneumoniae was the most common isolated pathogen in southern Taiwan.

Eur J Clin Microbiol Infect Dis, 2004 Mar, 23(3), 200 - 2 Epub 2004 Feb 07.
Protocol for the accelerated detection of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae strains from blood cultures; Navon-Venezia S et al.; The study presented here was performed to evaluate an accelerated protocol for the early detection of organisms producing extended-spectrum beta-lactamase (ESBL) . The procedure involved testing isolates directly from positive blood-culture bottles, and a total of 40 clinical isolates (10 ESBL-producing and 10 non-ESBL-producing isolates of both Escherichia coli and Klebsiella pneumoniae) were used . The isolates were inoculated into blood cultures bottles and, upon growth signal, fluid from the bottle was cultured directly onto plates with combination discs containing cefotaxime or ceftazidime with and without clavulanate . Results were compared with those of standard methods for the detection of ESBL . High concordance between the two methods was found, and the direct test showed high sensitivity (95%) and specificity (100%) . Use of this accelerated protocol may speed detection of the ESBL phenotype and thereby facilitate the early administration of appropriate antimicrobial therapy.

Res Microbiol, 2004 Jan-Feb, 155(1), 17 - 23
Discrimination of Klebsiella pneumoniae and Klebsiella oxytoca phylogenetic groups and other Klebsiella species by use of amplified fragment length polymorphism; Jonas D et al.; Bacteria of the genus Klebsiella are opportunistic pathogens responsible for an increasing number of multiresistant infections in hospitals . The two clinically and epidemiologically most important species, Klebsiella pneumoniae and K . oxytoca, have recently been shown to be subdivided into three and two phylogenetic groups, respectively . The aim of this study was an in depth evaluation of the amplified fragment length polymorphism (AFLP) genetic characterization method for epidemiological and phylogenic analyzes of Klebsiella isolates . First, we investigated the variability of AFLP patterns for Klebsiella strains within and between different outbreaks . Second, by use of carefully characterized phylogenetically representative strains, we examined whether different Klebsiella species and phylogenetic groups can be discriminated using AFLP . Twenty-four strains originating from seven presumed outbreaks and 31 non-associated strains were investigated . The AFLP fingerprints of all epidemiologically associated strains showed three or fewer fragment differences, whereas unrelated strains differed by at least four fragments . Cluster analysis of the AFLP data revealed a very high concordance with the phylogenetic assignation of strains based on the gyrA sequence and ribotyping data . The species K . pneumoniae, K . oxytoca, K . terrigena and the possibly synonymous pair K . planticola/K . ornithinolytica each formed a separate cluster . Similarly, strains of the phylogenetic groups of K . pneumoniae and K . oxytoca fell into their corresponding clusters, with only two exceptions . This study provides a preliminary cut-off value for distinguishing epidemiologically non-related Klebsiella isolates based on AFLP data; it confirms the sharp delineation of the recently identified phylogenetic groups, and demonstrates that AFLP is suitable for identification of Klebsiella species and phylogenetic groups.

Zhonghua Er Ke Za Zhi, 2003 May, 41(5), 352 - 6
{Evaluation of antibacterial activity of amoxycillin sodium and clavulanate potassium and the pharmacoeconomics in the therapy of acute respiratory infection}; Xu F et al.; OBJECTIVE: To explore the antibacterial activity of amoxycillin sodium and clavulanate potassium (trade name: Anqi) in vitro and the pharmacoeconomics in the therapy of acute respiratory infection . METHODS: Minimal inhibition concentration (MIC), minimal bactericidal concentration (MBC) and bactericidal curve of amoxycillin sodium and clavulanate potassium against common pathogens were determined and compared with some other same kind of antibiotics without beta-Lactamase inhibitor . Eighty cases diagnosed as respiratory infection were randomly divided into 4 groups: group 1 was treated with i.v . Anqi; group 2 was treated with i.v . Anqi and oral consecutive strategy; group 3 was treated with iv ampicillin and sulbactam; group 4 was treated with i.v . cefuroxime . The clinical therapeutic effects were observed and cost-effectiveness analyzed . RESULTS: In terms of MIC, MBC and bactericidal curve of 135 bacterial strains, Anqi was superior to the other same-kind antibiotics without beta-lactamase inhibitor, this effect was especially obvious on Klebsiella pneumoniae and Escherichia coli which can produce extended spectrum beta-lactamases (ESBLs) . The cost-effectiveness of the consecutive therapy group was the best . CONCLUSION: Anqi has a wide antimicrobial spectrum and strong effect on the bacteria producing ESBLs, the consecutive therapy strategy should be clinically recommended.

J Biol Chem, 2004 Apr 9, 279(15), 15305 - 13 Epub 2004 Jan 28.
Chemical cross-linking and mass spectrometric identification of sites of interaction for UreD, UreF, and urease; Chang Z et al.; Synthesis of active Klebsiella aerogenes urease requires four accessory proteins to generate, in a GTP-dependent process, a dinuclear nickel active site with the metal ions bridged by a carbamylated lysine residue . The UreD and UreF accessory proteins form stable complexes with urease apoprotein, comprised of UreA, UreB, and UreC . The sites of protein-protein interactions were explored by using homobifunctional amino group-specific chemical cross-linkers with reactive residues being identified by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) of tryptic peptides . On the basis of studies of the UreABCD complex, UreD is capable of cross-linking with UreB Lys(9), UreB Lys(76), and UreC Lys(401) . Furthermore UreD appears to be positioned over UreC Lys(515) according to decreased reactivity of this residue compared with its reactivity in UreD-free apoprotein . Several UreB-UreC and UreC-UreC cross-links also were observed within this complex; e.g . UreB Lys(76) with the UreC amino terminus, UreB Lys(9) with UreC Lys(20), and UreC Lys(515) with UreC Lys(89) . These interactions are consistent with the proximate surface locations of these residues observed in the UreABC crystal structure . MALDI-TOF MS analyses of UreABCDF are consistent with a cross-link between the UreF amino terminus and UreB Lys(76) . On the basis of an unexpected cross-link between UreB Lys(76) and UreC Lys(382) (distant from each other in the UreABC structure) along with increased side chain reactivities for UreC Lys(515) and Lys(522), UreF is proposed to induce a conformational change within urease that repositions UreB and potentially could increase the accessibility of nickel ions and CO(2) to residues that form the active site.

Indian J Med Res, 2003 Jul, 118, 47 - 52
Induction & resolution of lobar pneumonia following intranasal instillation with Klebsiella pneumoniae in mice; Yadav V et al.; BACKGROUND & OBJECTIVES: Pneumonia caused by Klebsiella pneumoniae is important due to its high morbidity and mortality, especially in context of nosocomial infections . Many experimental studies have focused on the induction and progression of infection till it peaks, but the process of resolution has not been described . In the present study, we successfully attempted to establish an acute respiratory tract infection model in BALB/c strain of mice with K . pneumoniae employing a simple, reproducible intranasal instillation method . METHODS: Experimental pneumonia was induced by two strains of K . pneumoniae in BALB/c mice following intranasal instillation, and the course of pneumonia was studied by bacteriological and histopathological evaluation of the lung tissue . RESULTS: Both the strains were similar in their ability to induce infection which peaked on day 3, post infection . However, a strain dependent difference in relation to bacterial load and the process of resolution was observed . INTERPRETATION & CONCLUSION: The present study provides a model of lobar pneumonia produced by K . pneumoniae which can be useful for studying therapeutic and preventive interventions.

Acta Crystallogr D Biol Crystallogr, 2004 Feb, 60(Pt 2), 326 - 8 Epub 2004 Jan 23.
Expression, purification and crystallization of an extended-spectrum beta-lactamase from Klebsiella oxytoca; Wu SW et al.; OXY-1a is an extended-spectrum beta-lactamase from the conditional pathogenic bacterium Klebsiella oxytoca . OXY-1a is responsible for the antibiotic resistance of this pathogen . A soluble form of OXY-1a with a His tag at its C-terminus was overexpressed in Escherichia coli . The recombinant protein was purified and crystallized at room temperature using PEG 4000 as the main precipitant . Two crystal forms were obtained from the same growth conditions . One was orthorhombic, with crystals that diffracted to better than 1.9 A, while the other was tetragonal, with crystals that only diffracted to about 3.0 A . Complete data sets were collected from both crystal forms . The orthorhombic crystal belongs to space group P2(1)2(1)2(1), with unit-cell parameters a = 46.54, b = 73.43, c = 84.56 A, while the tetragonal crystal has unit-cell parameters a = b = 73.72, c = 96.81 A . The asymmetric unit of the orthorhombic crystal is estimated to contain one OXY-1a molecule, giving a crystal volume per protein weight (V(M)) of 2.25 A(3) Da(-1) and a solvent content of 45%.

Lett Appl Microbiol, 2004, 38(2), 146 - 50
Identification of heat stable protease of Klebsiella oxytoca isolated from raw milk; Tondo EC et al.; AIMS: The aim of this study was to identify and characterize heat stable proteinases of psychrotrophic proteolytic bacteria isolated from raw milk . METHODS AND RESULTS: A strain of Klebsiella oxytoca producing a high proteolytic activity when cultured on milk was isolated . Maximum proteolytic activity was observed at the stationary phase during growth on milk or casein-peptone broth . The bacterium demonstrated the capability to grow at 7 degrees C, classified as psychrotrophic . The crude enzyme showed optimum activity at 37 degrees C, and pH 5.0 and 7.0 . The proteinase was very resistant to heat, maintaining 74% of initial activity after incubation at 142 degrees C . CONCLUSIONS: A heat stable protease of a psychrotrophic strain of K . oxytoca was identified and partially characterized . SIGNIFICANCE AND IMPACT OF THE STUDY: Thermal stable proteases may constitute a serious problem to ultra-high temperature (UHT) processed milk, leading to undesirable physical and sensory alterations.

Antimicrob Agents Chemother, 2004 Feb, 48(2), 629 - 31
CTX-M-12 beta-lactamase in a Klebsiella pneumoniae clinical isolate in Colombia; Villegas MV et al.; We describe the detection of the CTX-M-12 beta-lactamase from a clinical isolate of Klebsiella pneumoniae in Colombia . Screening of nosocomial Klebsiella spp . and Escherichia coli isolates from a network of teaching hospitals revealed the presence of CTX-M enzymes in multiple cities . This is the first description of CTX-M in Colombia.

Antimicrob Agents Chemother, 2004 Feb, 48(2), 533 - 7
Epidemiology of conjugative plasmid-mediated AmpC beta-lactamases in the United States; Alvarez M et al.; A sample of 752 resistant Klebsiella pneumoniae, Klebsiella oxytoca, and Escherichia coli strains from 70 sites in 25 U.S . states and the District of Columbia was examined for transmissibility of resistance to ceftazidime and the nature of the plasmid-mediated beta-lactamase involved . Fifty-nine percent of the K . pneumoniae, 24% of the K . oxytoca, and 44% of the E . coli isolates transferred resistance to ceftazidime . Plasmids encoding AmpC-type beta-lactamase were found in 8.5% of the K . pneumoniae samples, 6.9% of the K . oxytoca samples, and 4% of the E . coli samples, at 20 of the 70 sites and in 10 of the 25 states . ACT-1 beta-lactamase was found at eight sites, four of which were near New York City, where the ACT-1 enzyme was first discovered; ACT-1 beta-lactamase was also found in Massachusetts, Pennsylvania, and Virginia . FOX-5 beta-lactamase was also found at eight sites, mainly in southeastern states but also in New York . Two E . coli strains produced CMY-2, and one K . pneumoniae strain produced DHA-1 beta-lactamase . Pulsed-field gel electrophoresis and plasmid analysis suggested that AmpC-mediated resistance spread both by strain and plasmid dissemination . All AmpC beta-lactamase-containing isolates were resistant to cefoxitin, but so were 11% of strains containing transmissible SHV- and TEM-type extended-spectrum beta-lactamases . A beta-lactamase inhibitor test was helpful in distinguishing the two types of resistance but was not definitive since 24% of clinical isolates producing AmpC beta-lactamase had a positive response to clavulanic acid . Coexistence of AmpC and extended-spectrum beta-lactamases was the main reason for these discrepancies . Plasmid-mediated AmpC-type enzymes are thus responsible for an appreciable fraction of resistance in clinical isolates of Klebsiella spp . and E . coli, are disseminated around the United States, and are not so easily distinguished from other enzymes that mediate resistance to oxyimino-beta-lactams.

Appl Microbiol Biotechnol, 2004 Jul, 65(1), 110 - 8 Epub 2004 Jan 16.
Molecular and physiological characterisation of a 3-phytase from soil bacterium Klebsiella sp . ASR1; Sajidan A et al.; Klebsiella sp . strain ASR1 isolated from an Indonesian rice field is able to hydrolyse myo-inositol hexakis phosphate (phytate) . The phytase protein was purified and characterised as a 42 kDa protein accepting phytate, NADP and sugar phosphates as substrates . The corresponding gene (phyK) was cloned from chromosomal DNA using a combined approach of protein and genome analysis, and expressed in Escherichia coli . The recombinant enzyme was identified as a 3-phytase yielding myo-inositol monophosphate, Ins(2)P, as the final product of enzymatic phytate hydrolysis . Based on its amino acid sequence, PhyK appears to be a member of a hitherto unknown subfamily of histidine acid phytate-degrading enzymes with the active site RHGXRXP and HD sequence motifs, and is different from other general phosphatases and phytases . Due to its ability to degrade sodium phytate to the mono phosphate ester, the phyK gene product is an interesting candidate for industrial and agricultural applications to make phytate phosphorous available for plant and animal nutrition.

Pathol Int, 2004 Feb, 54(2), 101 - 4
Rhinoscleroma associated with Rosai-Dorfman reaction of regional lymph nodes; Kasper HU et al.; Rhinoscleroma is an uncommon chronic, destructive infection of the respiratory mucosa caused by Klebsiella rhinoscleromatis . This coccobacillus can be found in the typical histiocytes, the Mikulicz cells . Extranasal and nodal involvement in this disease is rare, but documented . Rosai-Dorfman disease or sinus histiocytosis with massive lymphadenopathy is also a rare, non-hereditary disorder . Bilateral cervical lymphadenopathy with emperipolesis, as the main histological characteristic, is the most common presentation . It can also occur extranodally . We report a case of rhinoscleroma occurring in a 62-year-old woman since 1984, who developed parotid gland and lymph node involvement . The changes in the nasal mucosa and the parotid gland showed chronic inflammation with Mikulicz cells . In the lymph nodes, features characteristic of Rosai-Dorfman disease were seen . Taking into consideration the literature dealing with both of these diseases, we discuss that Rosai-Dorfman disease could be a special type of lymph node reaction and is not necessarily an entity of its own . Therefore, it should be known as Rosai-Dorfman lymph node reaction . Furthermore, there seems to be an interconnection between Rosai-Dorfman disease and rhinoscleroma.

Am J Respir Med, 2002, 1(3), 177 - 83
Peptide receptor imaging: advances in the diagnosis of pulmonary diseases; Van de Wiele C et al.; Radiolabeled cell-surface peptide receptor-binding molecules are emerging as an important class of radiopharmaceuticals . Their binding to specific cell membrane receptors allows for noninvasive assessment of regional receptor proteomics in vivo . Information thus obtained can be used for diagnostic purposes and for predicting and monitoring response to treatment . This paradigm also applies to pulmonary diseases . In this review, available radiopharmaceuticals of great potential or already in clinical use for imaging of lung cancer, lung inflammation and infection and pulmonary embolism are discussed . In lung cancer, somatostatin receptor imaging by means of technetium-99m (99mTc)-octreotide scintigraphy has proven useful for characterizing malignancy in solitary pulmonary nodules . Additionally, several radiopharmaceuticals targeting tyrosine-kinase, e.g . 99mTc labeled epidermal growth factor and indium-111 (111In)-diethylene triamine penta-acetic acid-trastuzumab, or G-protein coupled receptors, e.g . 99mTc-bombesin, iodine-123-vasoactive intestinal peptide and 111In-tetraazacyclododecane tetra-acetic acid (DOTA)-cholecystokinine-B, are being explored for their diagnostic as well as treatment monitoring potential . With the purpose of better evaluating the source of pulmonary embolism, as well as to differentiate acute from chronic deep venous thrombosis, several radiolabeled peptides targeting the glycoprotein IIb/IIIa fibrinogen receptor found on activated platelets have been developed . Out of these, 99mTc-P280 is now approved by the US Food and Drug Administration for scintigraphic imaging of suspected acute venous thrombosis in the lower extremities of patients . In the field of lung inflammation and infection, non-specific 111In and 99mTc-human polyclonal immunoglobulins have been successfully used to identify the presence and extent of Pneumocystis carinii, cytomegalovirus, Mycobaterium avium and fungal infections in patients with HIV infection . The clinical role of other radiopharmaceuticals such as 99mTc-J001X, a nonpyrogenic acylated polygalactoside isolated from Klebsiella pneumoniae and binding with high affinity to CD11b and CD14 lipopolysaccharide receptors expressed on monocytes/macrophages, and 111In-octreotide, binding to up-regulated somatostatin receptors on activated lymphocytes needs to be further defined.

J Clin Microbiol, 2004 Jan, 42(1), 269 - 75
Effects of inoculum and beta-lactamase activity in AmpC- and extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae clinical isolates tested by using NCCLS ESBL methodology; Queenan AM et al.; Escherichia coli and Klebsiella pneumoniae isolates with extended-spectrum beta-lactamases (ESBLs) or AmpC cephalosporinases generally respond as predicted to NCCLS tests for ESBL production . However, inoculum size may affect MICs . The effect of inoculum level in clinical isolates expressing beta-lactamases were studied at inocula within 0.5 log unit of the standard inoculum, using broth microdilution methodology with ceftazidime, cefotaxime, cefepime, cefpodoxime, and aztreonam . Strains with TEM-1 or no beta-lactamases gave consistent MIC results with inocula of 10(5) and 10(6) CFU/ml . When the bacteria were screened for ESBL production and the lower inoculum was used, several strains with ESBLs, including CTX-M-10, TEM-3, TEM-10, TEM-12, TEM-6, SHV-18, and K1, gave false-negative results for one or more antimicrobial agents (MICs below the NCCLS screening concentration for detecting suspected ESBLs) . When the higher inoculum was used, MICs of at least one antimicrobial agent increased at least fourfold in strains producing TEM-3, TEM-10, TEM-28, TEM-43, SHV-5, SHV-18, and K1 . All antimicrobial agents showed an inoculum effect with at least one ESBL producer . Confirmatory clavulanate effects were seen for both inocula for all ESBL-producing strains with all antimicrobial agents tested, except for the CTX-M-10-producing E . coli with ceftazidime and the SHV-18-producing K . pneumoniae with cefotaxime . In kinetic studies, cefpodoxime and cefepime were hydrolyzed by ESBLs in a manner similar to that of cefotaxime . When total beta-lactamase activity and hydrolysis parameters were evaluated, however, no single factor was predictive of inoculum effects . These results indicate that the NCCLS screening and confirmation tests are generally predictive of ESBL production, but false-negative results can arise when a lower inoculum is used in testing.

J Clin Microbiol, 2004 Jan, 42(1), 30 - 5
Clonal and horizontal dissemination of Klebsiella pneumoniae expressing SHV-5 extended-spectrum beta-lactamase in a Mexican pediatric hospital; Miranda G et al.; One hundred eighty-four clinical isolates of Klebsiella pneumoniae were recovered from August 1996 to October 1997 at the Pediatric Hospital of the Instituto Mexicano del Seguro Social in Mexico City, Mexico . Most of the isolates were collected from the neonatal intensive care unit and infant wards, which are located on the same floor of the hospital . Isolates were genotypically compared by pulsed-field gel electrophoresis with XbaI restriction of chromosomal DNA . Of 184 clinical isolates, 91 belonged to cluster A and comprised three subtypes (A1, A2, and A3), while 93 isolates, comprising two minor clones, B (10 isolates) and C (7 isolates), and 76 unique patterns, were considered unrelated isolates (URI) . Susceptibility patterns were indistinguishable in both groups . Fifty extended-spectrum beta-lactamase-producing isolates, including 34 from clone A and 16 from URI, were examined for further studies . Molecular and genetic analysis showed that 47 of 50 clinical isolates expressed the SHV-5 beta-lactamase . This enzyme, in combination with TEM-1, was encoded in a >or=170-kb conjugative plasmid . Results indicate that dissemination of this resistance was due to clonal and horizontal spread.

Plasmid, 2004 Jan, 51(1), 48 - 53
The SHV-5 extended-spectrum beta-lactamase gene of pACM1 is located on the remnant of a compound transposon; Preston KE et al.; The SHV-5 extended-spectrum beta-lactamase gene of pACM1 was previously shown to reside on a segment of DNA ( approximately 7.9 kb) homologous to part of the Klebsiella pneumoniae chromosome . Regions of pACM1 overlapping the ends of the homology were sequenced . A defective copy of IS26 was found on each side of, and immediately adjacent to, the homology . The copies were oriented as direct repeats reminiscent of the compound transposon Tn2680 . Other mobile elements and a putative mutagenesis gene, several of which were also defective, were also located in the vicinity of the homology . An intact precursor to the transposon remnant might have contributed to the dissemination of the SHV-5 gene.

Ann Intern Med, 2004 Jan 6, 140(1), 26 - 32
International prospective study of Klebsiella pneumoniae bacteremia: implications of extended-spectrum beta-lactamase production in nosocomial Infections; Paterson DL et al.; BACKGROUND: Commonly encountered nosocomially acquired gram-negative bacteria, especially Klebsiella pneumoniae, produce extended-spectrum beta-lactamases (ESBLs) as an antibiotic resistance mechanism . OBJECTIVE: To determine whether microbiology laboratories should report the presence of ESBLs and to establish the infection-control implications of ESBL-producing organisms . DESIGN: Prospective observational study . SETTING: 12 hospitals in South Africa, Taiwan, Australia, Argentina, the United States, Belgium, and Turkey . PATIENTS: 440 patients with 455 consecutive episodes of K . pneumoniae bacteremia between 1 January 1996 and 31 December 1997; of these, 253 episodes were nosocomially acquired . MEASUREMENTS: The K . pneumoniae isolates were examined for the presence of ESBLs . Pulsed-field gel electrophoresis was used to analyze the molecular epidemiology of nosocomial bacteremia with ESBL-producing K . pneumoniae . RESULTS: Overall, 30.8% (78 of 253) episodes of nosocomial bacteremia and 43.5% (30 of 69) episodes acquired in intensive care units were due to ESBL-producing organisms . After adjustment for potentially confounding variables, previous administration of beta-lactam antibiotics containing an oxyimino group (cefuroxime, cefotaxime, ceftriaxone, ceftazidime, or aztreonam) was associated with bacteremia due to ESBL-producing strains (risk ratio, 3.9 {95% CI, 1.1 to 13.8}) . In 7 of 10 hospitals with more than 1 ESBL-producing isolate, multiple strains with the same genotypic pattern were observed, indicating patient-to-patient spread of the organism . CONCLUSIONS: Production of ESBLs by Klebsiella pneumoniae is a widespread nosocomial problem . Appropriate infection control and antibiotic management strategies are needed to stem the spread of this emerging form of resistance.

Clin Infect Dis, 2004 Jan 15, 38(2), 243 - 51 Epub 2003 Dec 19.
Bacteremia due to Klebsiella pneumoniae isolates producing the TEM-52 extended-spectrum beta-lactamase: treatment outcome of patients receiving imipenem or ciprofloxacin; Endimiani A et al.; The treatment outcome of 35 cases of bacteremia due to Klebsiella pneumoniae isolates producing TEM-52 extended-spectrum beta-lactamase was studied . Twenty-eight cases, classified as "nonfatal disease" using the McCabe and Jackson classification, were investigated with regard to ciprofloxacin and imipenem response . Because ciprofloxacin was active in vitro against 21 of 28 isolates, only the treatment outcome of the ciprofloxacin-susceptible subgroup was evaluated . Eight of 10 cases occurred in patients who experienced a complete response to imipenem; 2 of 10 failed to respond . In contrast, only 2 of 7 cases had a partial response to ciprofloxacin, and, in 5 of 7 cases, the treatment failed . Statistical analysis revealed a significant difference in the treatment outcome of the 2 groups (P=.03) . Because the isolates had minimum inhibitory concentrations of ciprofloxacin close to the susceptibility breakpoint, treatment failure could be ascribed to the inability of the drug to reach therapeutic concentrations at infected sites.

Taehan Kan Hakhoe Chi, 2003 Dec, 9(4), 275 - 83
{Recent changes of organism and treatment in pyogenic liver abscess}; Nah BK et al.; BACKGROUND/AIMS: With the advance of antibiotics and the development of newer imaging techniques, marked changes in etiology, diagnosis, treatment and prognosis of liver abscess have been reported . METHODS: We reviewed the clinical data related to 94 patients with pyogenic liver abscess . RESULTS: Of the 94 patients in the study group, the male to female ratio was 1.4:1 and the peak incidence of liver abcess was in the 7th decade . About three quaters (74.5%) of the abcesses were of unknown origin . The predominant location was in the right lobe (70.3%) . Single lesion was found in 80 patients and multiple lesions in 14 patients . Pathogens were identified in 67 patients, of which Klebsiella pneumoniae (65.7%) and E . coli (16.4%) were the most common . The modalities of treatment were percutaneous drainage with antibiotics (73.4%), percutaneous aspiration with antibiotics (16.0%), or antibiotics alone (8.5%) . The case fatality rate, mainly from associated underlying diseases, was 9 cases (9.6%) . Associated diseases were diabetes mellitus (14.9%) and malignancy (10.6%) . CONCLUSIONS: Our study revealed that the most common organism was Klebsiella pneumoniae and percutaneous needle aspiration and/or catheter drainage were safe and effective treatment modalities for pyogenic liver abscess . Prognosis was determined by the underlying condition.

Antimicrob Agents Chemother, 2004 Jan, 48(1), 348 - 51
Chromosome-encoded ambler class D beta-lactamase of Shewanella oneidensis as a progenitor of carbapenem-hydrolyzing oxacillinase; Poirel L et al.; A chromosome-encoded beta-lactamase gene from a Shewanella oneidensis reference strain was cloned and expressed in Escherichia coli . It encoded a carbapenem-hydrolyzing Ambler class D beta-lactamase, OXA-54, that shared 92% amino acid identity with the plasmid-encoded carbapenem-hydrolyzing oxacillinase OXA-48 from Klebsiella pneumoniae . This work suggests that Shewanella spp . may produce the progenitor of oxacillinases compromising the efficacy of imipenem in clinically relevant gram-negative pathogens.

Antimicrob Agents Chemother, 2004 Jan, 48(1), 15 - 22
Emergence of oxacillinase-mediated resistance to imipenem in Klebsiella pneumoniae; Poirel L et al.; Klebsiella pneumoniae strain 11978 was isolated in Turkey in 2001 and was found to be resistant to all beta-lactams, including carbapenems . Cloning and expression in Escherichia coli identified five beta-lactamases, including two novel oxacillinases . The beta-lactamase OXA-48 hydrolyzed imipenem at a high level and was remotely related (less than 46% amino acid identity) to the other oxacillinases . It hydrolyzed penicillins and imipenem but not expanded-spectrum cephalosporins . The bla(OXA-48) gene was plasmid encoded and not associated with an integron, in contrast to most of the oxacillinase genes . An insertion sequence, IS1999, was found immediately upstream of bla(OXA-48) . Another plasmid that encoded a second oxacillinase gene, bla(OXA-47), located inside a class 1 integron was identified in K . pneumoniae 11978 . OXA-47 had a narrow spectrum of hydrolysis activity and did not hydrolyze ceftazidime or imipenem, as is found for the beta-lactamase (OXA-1) to which it is related . In addition, beta-lactamases TEM-1 and SHV-2a were expressed from the same K . pneumoniae isolate . Analysis of the outer membrane proteins of this isolate revealed that it lacked a porin of ca . 36 kDa . Thus, the high-level resistance to beta-lactams of this clinical isolate resulted from peculiar beta-lactamases and modification of outer membrane proteins.

J Pediatr (Rio J), 1996 Jul-Aug, 72(4), 230 - 4
{Septicaemia caused by Klebsiella pneumoniae--a review of 28 cases}; Escobar AM et al.; Twenty-eight children with septicaemia and positive blood cultures for Klebsiella pneumoniae were retrospectively studied and compared with 190 children with sepsis caused by other organisms, identified or not in blood cultures . Septicaemia due to Klebsiella pneumoniae occurred more frequently in children older than 2 years of age, especially those who had an underlying disease and, therefore, were malnourished or had an impaired immune defense system that had required invasive procedures and previous hospitalization . Although the case fatality rate was high in both groups, Klebsiella pneumoniae did not contribute to elevate the relative risk of death . In this study, Klebsiella pneumoniae isolates were highly sensitive to colistin (92.9%) and cefoxitin (82.1%), but poorly sensitive to third generation cephalosporin and imipenen.

J Pediatr (Rio J), 1999 Sep-Oct, 75(5), 361 - 6
{Joint effort to improve quality in a Brazilian pediatric public hospital through cross-infection control}; Lopes JM et al.; OBJECTIVES: To examine the role of the laboratory in nosocomial infection control from January 1993 to December 1996 in Centro Geral de Pediatria of Hospital Foundation of Minas Gerais state . METHODS: Follow -up of 101,139 patient-days (11,147 discharges + deaths + transfers) in the wards and intensive care unit by using the National Nosocomial Infection Surveillance (NNIS) system proposed by the Centers for Disease Control and Prevention (CDC- Atlanta) . Prospective surveillance of nosocomial infections at all sites was performed according to the hospital - wide (since 1992) and intensive care unit (since 1996) NNIS components . The CDC definitions since 1988 and Brazilian Ministry of Health regulation number 930 since 1992 were used to diagnose the nosocomial infections . RESULTS: The five most frequent nosocomial pathogens (from a total of 139 isolates) were Klebsiella sp = 24.5%; S . aureus = 18%; P . aeruginosa = 13.7%; E . coli = 12.9%; S . epidermidis = 12.2% . The percentage of identification of pathogens isolated from nosocomial infection sites has increased from 6.2% in 1993 to 13.3% in 1995 and 28.2% in 1996 (p< 0.001) and so has the attempt to isolate the pathogens: 7.5% in 1993, 16.1% in 1995, 33.8% in 1996 (p< 0.001) . The time interval taken for lab results (from specimen collected to microbiology result) has decreased from the average of ten days in 1993 to six days in 1996 (p = 0.001) . CONCLUSIONS: The continuing education and improved communication among infection control personnel, pediatricians, surgeons and members of the laboratory have proven to play a key role in the epidemiology of nosocomial infections by defining their etiologies in the Centro Geral de Pediatria . A task force to determine the microbiology has been achieved by the understanding of all clinicians that it is important to treat their patients specifically . The NNIS method applied to Brazilian hospitals has shown its impact on the microbiology lab role in nosocomial infection control as well.

J Nippon Med Sch, 2003 Dec, 70(6), 515 - 8
Infected solitary hepatic cyst; Yoshida H et al.; An unusual case involving an infected hepatic cyst in which the correct diagnosis was made without operation is reported . A 93-year-old woman presented with acute onset of right upper quadrant abdominal pain, mild left lower quadrant abdominal pain, diarrhea, and fever . On admission, computed tomography revealed a 15 cm solitary hepatic cyst in the anterior-superior segment of the liver with a thickened wall that enhanced with contrast media . Ultrasonography demonstrated a 15 cm anechoic lesion with a hypoechoic area in the dependent portion of the cyst and a thickened wall . The serum concentration of C-reactive protein was 24.3 mg/dL, and the white blood cell count was 13,800/microL . A diagnosis of infected hepatic cyst was suspected, and percutaneous transhepatic drainage of the cyst was performed . Milky yellow fluid was obtained and the patient's right upper quadrant abdominal pain resolved after drainage . Klebsiella pneumoniae was cultured from the drainage fluid . The patient was discharged 20 days after drainage . Infection has not recurred and the hepatic cyst has not enlarged after 18 months.

Endocrinology, 2004 Apr, 145(4), 1933 - 42 Epub 2003 Dec 18.
Identification and characterization of an androgen-responsive gene encoding an aci-reductone dioxygenase-like protein in the rat prostate; Oram S et al.; The ALP1 {aci-reductone dioxygenase (ARD)-like protein 1} gene was identified in a comprehensive cDNA subtraction aimed at identifying genes regulated by androgens in the rat ventral prostate . ALP1 is homologous to the ARD/ARD' that were discovered in Klebsiella pneumoniae as enzymes that have the same polypeptide sequence and differ only in their metal content . This family of proteins is evolutionarily conserved from bacteria to humans and is involved in the methionine salvage pathway . Northern and Western blot confirmed the regulation of ALP1 by androgens in the rat ventral prostate . ALP1 mRNA is expressed in a variety of tissues; however, its regulation by androgens was specific to the prostate . ALP1 is expressed by the glandular epithelial cells of the rat prostate, with little or no expression in the stromal cells . ALP1 is down-regulated in the different rat Dunning tumor cell lines compared with the normal or castrated rat prostate . Expression studies showed that ALP1 overexpression is not tolerated by AT6.1 cells . Further studies demonstrated that ALP1 is also down-regulated in the human prostate cancer cell lines LNCaP, PC3, and DU145, and overexpression induces cell death in these cells . Taken together, our observations suggest that ALP1 may have an important role in androgen regulated prostate homeostasis as well as in prostate cancer progression by regulating cell death of prostate cancer cells.

Clin Infect Dis, 2004 Jan 1, 38(1), e7 - 9 Epub 2003 Dec 04.
Colistin for Klebsiella pneumoniae-associated sepsis; Karabinis A et al.; Klebsiella pneumoniae that was resistant to all available antibiotics (minimum inhibitory concentration of imipenem, 32 microg/mL), including carbapenems, was isolated from blood samples obtained from a 48-year-old patient in the intensive care unit . The patient developed septic shock, which was successfully treated with colistin, the only antibiotic with activity against this multidrug-resistant strain.

Water Res, 2004 Jan, 38(2), 301 - 8
Factors influencing inactivation of Klebsiella pneumoniae by chlorine and chloramine; Goel S et al.; Inactivation of Klebsiella pneumoniae cultures by chlorine and chloramine was evaluated under different growth conditions by varying nutrient media dilution, concentrations of essential inorganic nutrients (FeCl3, MgSO4, phosphate, and ammonium salts), and temperature . All inactivation assays were performed at room temperature (22-23 degrees C) and near neutral pH (7.2-7.5) . C*T(99.9) values for chlorine increased >20-fold and for chloramine increased 2.6-fold when cells were grown in 100-fold diluted nutrient broth (2NB) solutions (final TOC of 35-40 mg/L) . Background levels of Mg: 6.75 x 10(-2) mM and Fe: 3.58 x 10(-5) mM or high levels of FeCl3 (0.01 mM) and MgSO4 (1 mM) during growth resulted in the highest resistances to chlorine with C*T(99.9) values of 13.06 (+/-0.91) and 13.78 (+/-1.97) mg-min/L, respectively . Addition of low levels of FeCl3 (0.001 mM) and MgSO4 (0.1 mM) to K . pneumoniae cultures during growth resulted in the lowest bacterial resistances to inactivation; C*T(99.9) values ranged from 0.28 (+/-0.06) to 1.88 (+/-0.53)mg-min/L in these cultures . Increase in growth temperature from 22.5 degrees C to 35 degrees C for unamended 2NB cultures resulted in a 42-fold decrease in C*T(99.9) values for chlorine . A similar change in temperature resulted in no significant change in C*T(99.9) values for chloramine . These results indicate that inactivation of K . pneumoniae cultures by chlorine was highly sensitive to changes in growth conditions unlike inactivation by chloramine.

Kansenshogaku Zasshi, 2003 Nov, 77(11), 977 - 81
{A case of ventriculitis with bacterial meningitis occurred during the treatment of liver abscess}; Honma Y et al.; A 47-case-year old male was admitted to our hospital because of high fever and general fatigue . He had no immune deficiency, and had no other disease in his past history . On admission, the white blood cell count and C-reacted protein were severely elevated (18,700/microliter, 27.7 mg/dl, respectively) and abdominal CT revealed multiple low density, From these results, he was diagnosed as liver abscess . Intravenous MINO and SBT/CPZ injection were started . On the fifth hospital day, he suffered from headache and nuchal rigidity . The clinical data revealed the cerebro-spinal fluid (CSF) counting 8,336 cells/mm3 (mononuclear 8,000,) protein at 119 mg/dl, and sugar 42 mg/dl . CSF cultures were negative, but Klebsiella was recognized in the blood culture and drainage fluid in liver abscess . This condition was diagnosed as bacterial meningitis and antibiotics were changed to intravenous CTRX and MEPM . Furthermore we administered oral PSL and intravenous steroid-pulse therapy . After these combination therapies his condition improved gradually . After 40 hospital day, however, he suddenly had double vision, Axial FLAIR (SE6,000/120) image revealed with high signal intensity at 4th ventricle . Intravenous MEPM was administered again . On the 60th hospital day, double vision was gradually improved and abnormal intensity at 4th ventricle was almost disappeared . This case may provide us a considerable suggestion on the treatment of bacterial meningitis.

World J Gastroenterol, 2003 Dec, 9(12), 2821 - 3
Clinical predictors of severe gallbladder complications in acute acalculous cholecystitis; Wang AJ et al.; AIM: To evaluate the relationship between clinical information (including age, laboratory data, and sonographic findings) and severe complications, such as gangrene, perforation, or abscess, in patients with acute acalculous cholecystitis (AAC) . METHODS: The medical records of patients hospitalized from January 1997 to December 2002 with a diagnosis of acute cholecystitis were retrospectively reviewed to find those with AAC, confirmed at operation or by histologic examination . Data collected included age, sex, white blood cell count, AST, total bilirubin, alkaline phosphatase, bacteriology, mortality, and sonographic findings . The sonographic findings were recorded on a 3-point scale with 1 point each for gallbladder distention, gallbladder wall thickness >3.5 mm, and sludge . The patients were divided into 2 groups based on the presence (group A) or absence (group B) of severe gallbladder complications, defined as perforation, gangrene, or abscess . RESULTS: There were 52 cases of AAC, accounting for 3.7% of all cases of acute cholecystitis . Males predominated . Most patients were diagnosed by ultrasonography (48 of 52) or computed tomography (17 of 52) . Severe gallbladder complications were present in 27 patients (52%, group A) and absent in 25 (group B) . Six patients died with a mortality of 12% . Four of the 6 who died were in group A . Patients in group A were significantly older than those in group B (mean 60.88 y vs . 54.12 y, P=0.04) and had a significantly higher white blood cell count (mean 15,885.19 vs . 9,948.40, P=0.0005) . All the 6 patients who died had normal white blood cell counts with an elevated percentage of band forms . The most commonly cultured bacteria in both blood and bile were E . coli and Klebsiella pneumoniae . The cumulative sonographic points did not reliably distinguish between groups A and B, even though group A tended to have more points . CONCLUSION: Older patients with a high white cell count are more likely to have severe gallbladder complications . In these patients, earlier surgical intervention should be considered if the sonographic findings support the diagnosis of AAC.

J Immunol, 2003 Dec 15, 171(12), 6697 - 705
Outer membrane protein A from Klebsiella pneumoniae activates bronchial epithelial cells: implication in neutrophil recruitment; Pichavant M et al.; Aside from its mechanical barrier function, bronchial epithelium plays an important role both in the host defense and in the pathogenesis of inflammatory airway disorders . To investigate its role in lung defense, the effect of a bacterial cell wall protein, the outer membrane protein A from Klebsiella pneumoniae (kpOmpA) on bronchial epithelial cells (BEC) was evaluated on adhesion molecule expression and cytokine production . Moreover, the potential implication of this mechanism in kpOmpA-induced lung inflammation was also determined . Our in vitro studies demonstrated that kpOmpA strongly bound to BEAS-2B cells, a human BEC line, and to BEC primary cultures, resulting in NF-kappaB signaling pathway activation . Exposure to kpOmpA increased ICAM-1 mRNA and cell surface expression, as well as the secretion of IL-6, CXC chemokine ligand (CXCL)1, CXCL8, C-C chemokine ligand 2, CXCL10 by BEAS-2B cells, and BEC primary cultures (p < 0.005) . We analyzed in vivo the consequences of intratracheal injection of kpOmpA to BALB/c mice . In kpOmpA-treated mice, a transient neutrophilia (with a maximum at 24 h) was observed in bronchoalveolar lavage and lung sections . In vivo kpOmpA priming induced bronchial epithelium activation as evaluated by ICAM-1 and CXCL1 expression, associated with the secretion of CXCL1 and CXCL5 in bronchoalveolar lavage fluids . In the lung, an increased level of the IL-6, CXCL1, CXCL5, CXCL10 mRNA was observed with a maximum at 6 h . These data showed that kpOmpA is involved in host defense mechanism by its ability to activate not only APC but also BEC, resulting in a lung neutrophilia.

Biotechnol Prog, 2003 Nov-Dec, 19(6), 1697 - 702
Optimization of cyclodextrin glycosyltransferase production from Klebsiella pneumoniae AS-22 in batch, fed-batch, and continuous cultures; Gawande BN et al.; Production of a novel cyclodextrin glycosyltransferase (CGTase) from Klebsiella pneumoniae AS-22 strain, which converts starch predominantly to alpha-CD at high conversion yields, in batch, fed-batch, and continuous cultures, is presented . In batch fermentations, optimization of different operating parameters such as temperature, pH, agitation speed, and carbon-source concentration resulted in more than 6-fold increase in CGTase activity . The enzyme production was further improved by two fed-batch approaches . First, using glucose-based feed to increase cell density, followed by starch-based feed to induce enzyme production, resulted in high cell density of 76 g dry cell weight/L, although the CGTase production was low . Using the second approach of a single dextrin-based feed, 20-fold higher CGTase was produced compared to that in batch fermentations with media containing tapioca starch . In continuous operation, more than 8-fold increase in volumetric CGTase productivity was obtained using dextrin-based media compared to that in batch culture using starch-based media.

Proteome Sci . 2003 Dec 3;1(1):6.
Protein identification from two-dimensional gel electrophoresis analysis of Klebsiella pneumoniae by combined use of mass spectrometry data and raw genome sequences; Wang W et al.; Separation of proteins by two-dimensional gel electrophoresis (2-DE) coupled with identification of proteins through peptide mass fingerprinting (PMF) by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is the widely used technique for proteomic analysis . This approach relies, however, on the presence of the proteins studied in public-accessible protein databases or the availability of annotated genome sequences of an organism . In this work, we investigated the reliability of using raw genome sequences for identifying proteins by PMF without the need of additional information such as amino acid sequences . The method is demonstrated for proteomic analysis of Klebsiella pneumoniae grown anaerobically on glycerol . For 197 spots excised from 2-DE gels and submitted for mass spectrometric analysis 164 spots were clearly identified as 122 individual proteins . 95% of the 164 spots can be successfully identified merely by using peptide mass fingerprints and a strain-specific protein database (ProtKpn) constructed from the raw genome sequences of K . pneumoniae . Cross-species protein searching in the public databases mainly resulted in the identification of 57% of the 66 high expressed protein spots in comparison to 97% by using the ProtKpn database . 10 dha regulon related proteins that are essential for the initial enzymatic steps of anaerobic glycerol metabolism were successfully identified using the ProtKpn database, whereas none of them could be identified by cross-species searching . In conclusion, the use of strain-specific protein database constructed from raw genome sequences makes it possible to reliably identify most of the proteins from 2-DE analysis simply through peptide mass fingerprinting.

Eur J Clin Microbiol Infect Dis, 2004 Jan, 23(1), 20 - 6 Epub 2003 Dec 02.
Impairment of respiratory burst in polymorphonuclear leukocytes by extended-spectrum beta-lactamase-producing strains of Klebsiella pneumoniae; Sahly H et al.; The ability of extended-spectrum beta-lactamase (ESBL)-producing and non-ESBL-producing Klebsiella pneumoniae strains to induce a respiratory burst in polymorphonuclear leukocytes (PMNLs) was investigated . Ninety ESBL-producing and 178 non-ESBL-producing Klebsiella pneumoniae isolates were serotyped and their ability to induce a respiratory burst in PMNLs tested by monitoring the cells' chemiluminescence (CL) response . The percentage of isolates inducing high levels of CL response (CL>75%) was significantly higher among non-ESBL producers (52%) than among ESBL producers (32.2%) ( P<0.0001; OR=3.396; 95%CI=2.036-5.664) . The median CL response was significantly higher among the non-ESBL producers (76.9%) than among the ESBL producers (52.6%) ( P=0.034) . The two groups did not differ in their ability to resist intracellular killing by PMNLs ( P>0.05), with strains inducing high levels of CL response having significantly lower survival rates (31.8% vs . 42.4%) than strains inducing low levels of CL response (164% vs . 200%) ( P<0.01) . The frequencies of the K2 and the K25 serotypes were significantly higher among ESBL-producing strains (17.8% and 22.2%, respectively) than among the non-ESBL producers (6.2% and 1.7%, respectively) ( P=0.0057 and P<0.0001) . Of the 77 Klebsiella K serotypes, 71 were detectable among the non-ESBL producers, but only 24 were detectable among the ESBL producers . ESBL-producing Klebsiella pneumoniae strains might have a greater pathogenic potential by virtue of their ability to escape the phagocytic activity of PMNLs.

J Bacteriol, 2003 Dec, 185(24), 7213 - 21
The Klebsiella pneumoniae wabG gene: role in biosynthesis of the core lipopolysaccharide and virulence; Izquierdo L et al.; To determine the function of the wabG gene in the biosynthesis of the core lipopolysaccharide (LPS) of Klebsiella pneumoniae, we constructed wabG nonpolar mutants . Data obtained from the comparative chemical and structural analysis of LPS samples obtained from the wild type, the mutant strain, and the complemented mutant demonstrated that the wabG gene is involved in attachment to alpha-L-glycero-D-manno-heptopyranose II (L,D-HeppII) at the O-3 position of an alpha-D-galactopyranosyluronic acid (alpha-D-GalAp) residue . K . pneumoniae nonpolar wabG mutants were devoid of the cell-attached capsular polysaccharide but were still able to produce capsular polysaccharide . Similar results were obtained with K . pneumoniae nonpolar waaC and waaF mutants, which produce shorter LPS core molecules than do wabG mutants . Other outer core K . pneumoniae nonpolar mutants in the waa gene cluster were encapsulated . K . pneumoniae waaC, waaF, and wabG mutants were avirulent when tested in different animal models . Furthermore, these mutants were more sensitive to some hydrophobic compounds than the wild-type strains . All these characteristics were rescued by reintroduction of the waaC, waaF, and wabG genes from K . pneumoniae.

Am J Infect Control, 2003 Nov, 31(7), 424 - 30
A cluster of nosocomial Klebsiella pneumoniae bloodstream infections in a neonatal intensive care department: Identification of transmission and intervention; Gastmeier P et al.; OBJECTIVE: We sought to determine the cause and mode of transmission of a cluster of bloodstream infections as a result of Klebsiella pneumoniae . DESIGN AND SETTING: We conducted a prospective cohort study in a neonatal intensive care department from May 1999 to December 2000 . METHODS: We performed surveillance of nosocomial infections, and clinical and environmental investigations . RESULTS: During an 8-week period, 5 cases of K pneumoniae bloodstream infections were observed, at least 3 of them belonging to the same genotype . Before the second case developed any symptoms of infection, the same strain had also been found in the patient environment . Intervention measures were, therefore, immediately introduced . Further cases, however, occurred in the following weeks . Even after further intervention activities and the end of the outbreak, the same strain was discovered in environmental samples from a stethoscope and a nurse's hand . CONCLUSIONS: Even where there is acute awareness of the problem and a generally high infection control level in a department, it is difficult to change behavior in such a way that further nosocomial infections can be totally excluded.

Antimicrob Agents Chemother, 2003 Dec, 47(12), 3901 - 6
Novispirin G10-induced lung toxicity in a Klebsiella pneumoniae infection model; Bartlett KH et al.; Mammalian cathelicidins are a class of innate antimicrobial peptides isolated from leukocytes and epithelial cells that aid host defense against bacterial infections . Synthetic analogs of cathelicidins offer the promise of potent broad-spectrum antimicrobial efficacy . We developed a combined lung infection and ex vivo whole-blood assay model to characterize the toxicity and efficacy of synthetic cathelicidin-derived peptides . Male C57BL/6 mice were administered saline or Klebsiella pneumoniae by intratracheal instillation . Five hours later, the Klebsiella-infected mice were instilled with saline, tobramycin (1 mg/kg of body weight or 10 mg/kg), novispirin G10 (0.4 mg/kg), or a combination of tobramycin (1 mg/kg) and G10 (0.4 mg/kg) . At 24 h, bronchoalveolar lavage fluid (BAL) was collected for analysis of culturable bacteria and for markers of inflammation and lung toxicity . Blood samples were analyzed for circulating cytokines . Recovery of Klebsiella from the lung, recruitment of neutrophils, and production of interleukin-6 (IL-6) in BAL samples were highly correlated (r=0.68 and 0.84, respectively; P<0.01) . Animals treated with G10 or G10 plus tobramycin had increased hemoglobin (P<0.001) and protein (P<0.001) levels compared to those for Klebsiella-infected or tobramycin-alone-treated animals . The levels of circulating IL-6 in mice infected with Klebsiella were 1000- to 10,000-fold higher than in the noninfected controls . The highest levels of IL-6 were measured in mice given G10 alone or in combination with tobramycin . These studies demonstrated that G10 was relatively nontoxic in saline-treated mice but was highly toxic in mice infected with Klebsiella . This finding establishes the importance of investigating candidate antimicrobial agents in an in vivo infection model.

Antimicrob Agents Chemother, 2003 Dec, 47(12), 3881 - 9
Carbapenem-resistant strain of Klebsiella oxytoca harboring carbapenem-hydrolyzing beta-lactamase KPC-2; Yigit H et al.; We investigated a Klebsiella oxytoca isolate demonstrating resistance to imipenem, meropenem, extended-spectrum cephalosporins, and aztreonam . The MICs of both imipenem and meropenem were 32 microg/ml . The beta-lactamase activity against imipenem and meropenem was inhibited in the presence of clavulanic acid . Isoelectric focusing studies demonstrated five beta-lactamases with pIs of 8.2 (SHV-46), 6.7 (KPC-2), 6.5 (unknown), 6.4 (probable OXY-2), and 5.4 (TEM-1) . The presence of the bla(SHV) and bla(TEM) genes was confirmed by specific PCR assays and DNA sequence analysis . Transformation and conjugation studies with Escherichia coli showed that the beta-lactamase with a pI of 6.7, Klebsiella pneumoniae carbapenemase-2 (KPC-2), was encoded on an approximately 70-kb conjugative plasmid that also carried SHV-46, TEM-1, and the beta-lactamase with a pI of 6.5 . The bla(KPC-2) determinant was cloned in E . coli and conferred resistance to imipenem, meropenem, extended-spectrum cephalosporins, and aztreonam . The amino acid sequence of KPC-2 showed a single amino acid difference, S174G, when compared with KPC-1, another carbapenem-hydrolyzing beta-lactamase from K . pneumoniae 1534 . Hydrolysis studies showed that purified KPC-2 hydrolyzed not only carbapenems but also penicillins, cephalosporins, and aztreonam . KPC-2 had the highest affinity for meropenem . The kinetic studies revealed that KPC-2 was inhibited by clavulanic acid and tazobactam . An examination of the outer membrane proteins of the parent K . oxytoca strain demonstrated that it expressed detectable levels of OmpK36 (the homolog of OmpC) and a higher-molecular-weight OmpK35 (the homolog of OmpF) . Thus, carbapenem resistance in K . oxytoca 3127 is due to production of the Bush group 2f, class A, carbapenem-hydrolyzing beta-lactamase KPC-2 . This beta-lactamase is likely located on a transposon that is part of a conjugative plasmid and thus has a very high potential for dissemination.

Acta Paediatr, 2003 Oct, 92(10), 1205 - 7
Reduction in multiresistant nosocomial infections in neonates following substitution of ceftazidime with piperacillin/tazobactam in empiric antibiotic therapy; Flidel-Rimon O et al.; AIM: To evaluate the effect of a change in antibiotic protocol on pathogens that cause neonatal sepsis . METHODS: Suspected sepsis was treated with amikacin together with ceftazidime in 1995-1998 and piperacillin/tazobactam in 1999-2002 . RESULTS: The annual rate for Klebsiella sepsis fell from 2.5 to 0.45 cases per 1000 admission days (p = 0.0001) between the two periods studied . CONCLUSION: The change from ceftazidime to piperacillin/tazobactam is associated with a decrease in the incidence of Klebsiella sepsis.

Dig Dis Sci, 2003 Oct, 48(10), 1955 - 9
Preoperative antimicrobial administration for prevention of postoperative infection in patients with laparoscopic cholecystectomy; Uchiyama K et al.; The present study was designed to investigate whether the administration of antimicrobial agents before laparoscopic cholecystectomy (LC) is more effective for prevention of postoperative infection . During the period from January 1991 to September 2001, 397 patients treated with sulbactam/cefoperazone (SBT/CPZ) for prevention of postoperative infection were studied: 200 patients received SBT/CPZ 1 hr before LC, and 197 patients were not given the preoperative treatment . The positive rate of bacteria in the gallbladder bile in the group receiving preoperative SBT/CPZ was 12.0%, a significant suppression compared with 19.8% in the group without preoperative treatment (P < 0.05) . Identification of microorganisms in the bile revealed E . coli and Klebsiella in the preoperative treatment group, which showed a significant suppression (P < 0.05) . The mean white blood cell count was significantly lower in the preoperative treatment group (9860/microl) than in the nonpreoperative treatment group (10,520/microl) (P < 0.05) . The above results demonstrate that administration of SBT/CPZ before LC suppressed the level of bacteria in the bile, resulting in a significant reduction in complications induced by postoperative infection.

Pediatr Surg Int, 2003 Nov, 19(9-10), 632 - 4 Epub 2003 Nov 12.
Is it justified to obtain routine peritoneal fluid cultures during appendectomy in children?
Celik A, Ergun O, Ozcan C, Aldemir H, Balik E.
Controversy exists regarding obtaining routine peritoneal cultures during appendectomy . The aim of the study was to determine the impact of obtaining routine peritoneal fluid cultures during appendectomy on the treatment and clinical outcome in children . The charts of 269 children who were operated with the diagnosis of appendicitis between January 1996 and January 2001 were reviewed . The microorganisms in peritoneal cultures, selection of antibiotics and clinical outcome were evaluated . Average age was 10.1+/-3.3 (range, 1 to 17 years) years with a male to female ratio of 1.7 (170/99) . There were two groups of patients; Group 1: uncomplicated appendicitis (201/269=75%), and Group 2: complicated (perforated) appendicitis (49/269=18%) . In the series, 19 patients were found to have a normal appendix in histopathological examination (7%) . Cultures were obtained from 95 (35.3%) patients (group 1: 59/95, group 2: 36/95) . In patients with uncomplicated appendicitis, 6.7% of the cultures (4/59) were positive while in group 2, the rate was 47.2% (17/36) ( p<0.05) . Only in four patients who were in group 2, antibiotics were re-adjusted according to the cultures . Escherichia coli and Klebsiella pneumoniae were the most common microorganisms . There were no complications in group 1, while wound infection (18.3%) and intra-abdominal abscess (2%) were the two most common complications in group 2 . Intra-operative peritoneal cultures during appendectomy do not add much to the treatment of children . Therefore, it is not necessary to get peritoneal swab cultures during the procedures, and empiric use of wide spectrum antibiotics when necessary is generally sufficient in the management of this group of children.

J Antimicrob Chemother, 2003 Dec, 52(6), 899 - 903 Epub 2003 Nov 12.
Outer membrane protein alterations and blaTEM-1 variants: their role in beta-lactam resistance in Klebsiella pneumoniae; Nelson EC et al.; OBJECTIVES: The aim of the study was to characterize the genetic basis of resistance to selected beta-lactam antibiotics in two clinical isolates of Klebsiella pneumoniae . METHODS AND RESULTS: K . pneumoniae strains were isolated from two hospitalized patients . One of the strains was resistant to amoxicillin, co-amoxiclav, cefuroxime, piperacillin and cefoxitin but susceptible to all the other cephalosporins tested . The second strain displayed a similar phenotype except that it was resistant to piperacillin/tazobactam and susceptible to cefoxitin . PCR assays and DNA sequencing showed that the cefoxitin-susceptible strain contained a novel blaTEM-1 variant downstream of the strong Pa/Pb promoter . SDS-PAGE analysis of the outer membrane proteins (OMPs) did not identify OmpK35 and suggested reduced expression of OmpK36 in this strain . Following passage in non-selective media, expression of OmpK36 was restored with a concomitant increase in cefuroxime susceptibility . A similar experimental approach identified blaTEM-1C in the cefoxitin-resistant K . pneumoniae strain . This strain was deficient in OmpK35 and OmpK36; absence of the latter protein was due to the presence of IS1 in the ompK36 regulatory region . CONCLUSIONS: Resistance to selected beta-lactams in two clinical isolates of K . pneumoniae was due to interplay between the expression of OMPs and TEM-1.

World J Surg, 2004 Jan, 28(1), 38 - 42 Epub 2003 Nov 14.
Ocular manifestations and complications of pyogenic liver abscess; Tan YM et al.; In anecdotal reports, septic metastatic lesions from a pyogenic liver abscess can result in endogenous endophthalmitis, an infection of intraocular contents . Recent reports suggest that this devastating complication is increasing in frequency . The initial presentation may be nonspecific and easily misdiagnosed by the surgical team . When the infecting organism is virulent, it tends to be rapidly progressive and often leads to permanent visual deterioration or blindness despite medical intervention . We conducted a study to determine the incidence of endophthalmitis associated with pyogenic liver abscess, to identify its associations, and to determine the outcome of treatment . A retrospective review of 289 patients with a clinical diagnosis of pyogenic liver abscess admitted between January 1995 and March 2001 revealed 10 patients (3.5%) with the complication of endogenous endophthalmitis . Among them, seven had a previous history of diabetes mellitus . The offending organism was Klebsiella pneumoniae in all cases . There was no mortality in this series . Final visual outcomes of our patients were as follows: Five had no light perception (two had undergone evisceration), one had light perception only, and four were able to visualize hand motion only . There is a trend toward a worse outcome when ocular symptoms are not diagnosed and treated within 24 hours of onset . Of the five patients who lost their eyesight completely, three were initially misdiagnosed, and referral to the ophthalmologist was delayed . Surgeons must be alert to the complication of endogenous endophthalmitis . Ocular symptoms in patients treated for pyogenic liver abscess must be referred early for an ophthalmologic consult . Increased awareness and a high index of suspicion are required for salvage of visual function.

Scand J Infect Dis, 2003, 35(10), 700 - 3
Comparison of the E-test method with an automated bacterial identification and antimicrobial susceptibility detection system for screening extended-spectrum beta-lactamase producers; Ozakin C et al.; Some automated systems used in clinical microbiology laboratories are able to detect products responsible for antimicrobial resistance . In this study, 626 isolates (436 Escherichia coli, 134 Klebsiella pneumoniae and 56 Klebsiella oxytoca strains) were examined for the presumptive detection of extended-spectrum beta-lactamase (ESBL) production by 2 methods: the Sceptor system (BD, Sparks, MD, USA) and the E-test . ESBL production was detected in 26 E . coli strains (5.96%), 60 K . pneumoniae strains (44.77%) and 15 K . oxytoca strains (26.78%) by ceftazidime/ceftazidime-clavulanate E-test . Using the E-test, ESBL production was detected in 25 of 201 E . coli strains (12.43%), 55 of 75 K . pneumoniae (73.33%) and 14 of 27 K . oxytoca strains (51.85%) that were alerted as ESBL-producing strains by the Sceptor system . ESBL positivity was detected in 1 E . coli, 5 K . pneumoniae and 1 K . oxytoca strains, that were not warned as being ESBL producers by the Sceptor system . These data suggest that clinical microbiology laboratories should not only rely on these rapid automated systems but also use another method for screening ESBL producers, such as the E-test . The rates of these ESBL-producing isolates in this study were lower than those in other studies reported from other parts of Turkey, but higher than those reported from the USA and Europe.

J Trop Pediatr, 2003 Oct, 49(5), 295 - 7
Intravenous lines-related sepsis in newborn babies admitted to NICU in a developing country; Bakr AF; Nosocomial sepsis is very common in newborn units in developing countries . Routes of infection are multiple but the personal factor stays important . The hypothesis of this study was that intravenous lines may be important routes of infection and that contamination of cannula hub may preceded sepsis episodes . Infants in the neonatal intensive care unit level III were enrolled in the study . Culture samples were obtained from the intravenous line hubs every day until removed . At times of suspected sepsis, all patients had blood obtained for culture from a peripheral vein and from the i.v . line hubs at the same time . Sepsis was considered i.v . line-related if the micro-organism isolated from the peripheral blood culture was identical to the organism recovered from the cannula hub or tip or from purulent material at the site of skin entry of the cannula . Two hundred and sixty lines were placed in 83 patients . Forty-five episodes of sepsis were diagnosed clinically and by blood culturing . Klebsiella species was the predominant organism . Among the Klebsiella cases, the organism was isolated from the i.v . line hub in more than 50 per cent of the cases before the onset of clinical and laboratory sepsis, and in 14 per cent of the cases it was also isolated from the i.v . line hub at the time of sepsis . This study supports the hypothesis that the cannula hub is a major portal of entry for causing sepsis in newborn units.

Int J Antimicrob Agents, 2003 Nov, 22(5), 521 - 5
Dissemination and spread of CTX-M extended-spectrum beta-lactamases among clinical isolates of Klebsiella pneumoniae in central China; Li CR et al.; Of 50 extended-spectrum beta-lactamase-producing (ESBL) isolates of Klebsiella pneumoniae collected from six hospitals in Hubei Province, 20 were found to produce CTX-M ESBLs (40%) . Sequence analysis of the six isolates carrying bla(CTX-M) genes revealed that they all harboured bla(CTX-M-3) . In the majority of isolates, bla(CTX-M) genes were within large conjugative plasmids . A high degree of diversity of the RAPD types revealed that all the isolates carrying CTX-M were genetically unrelated and horizontal transfer of plasmids was probably the main mechanism of bla(CTX-M) spread . This is the first report of the occurrence of CTX-M-3 ESBLs in central China; previously this enzyme was identified only in Europe . A more comprehensive survey of ESBL types from China is urgently needed.

Am J Surg, 2003 Nov, 186(5), 493 - 9
A novel model of pneumonia from intraperitoneal injection of bacteria; Franklin GA et al.; BACKGROUND: Pneumonia remains a major clinical problem in the surgical patient . Experimental modeling by intratracheal injection of bacteria is not consistently reproducible . In an attempt to produce peritonitis by Klebsiella, we found evidence of pneumonia on autopsy and further developed this approach as a new experimental model . METHODS: Male Swiss Webster mice were given intraperitoneal (IP) injections of Klebsiella pneumoniae serotype 2 in different doses and this was compared with similar doses given intravenously (IV) . A dose dependent survival curve was generated . Subsequently, 10(3) colony forming units (CFU) of bacteria were used in further experiments . Blood, peritoneal fluid and lung tissue were collected at time points up to 72 hours after injection and were cultured for levels of bacteria . Lung weights and myeloperoxidase levels were also measured . RESULTS: Intraperitoneal administration of Klebsiella was uniformly lethal with as few as 10(2) bacteria . Lung weight increased after IP Klebsiella, and all animals became bacteremic within 24 hours correlating with high bacterial levels in the lung . Conversely, most animals (72%) survived IV injection of bacteria, and were able to clear bacteria from the blood and lung . CONCLUSIONS: We found that this model produced no clinically apparent peritonitis after 48 hours, but uniformly resulted in histopathologic changes of pneumonia by 24 hours . Survival time was related to initial dose of Klebsiella and there was a linear correlation between bacterial levels in the blood and lung . This model is reproducible, simple to perform, and the severity is easy to manipulate.

Pediatrics . 2003 Nov;112(5):e354.
Closure of patent ductus arteriosus with oral ibuprofen suspension in premature newborns: a pilot study; Heyman E et al.; OBJECTIVE: Patent ductus arteriosus (PDA), a common finding among premature infants, is conventionally treated by intravenous indomethacin . Intravenous ibuprofen was recently shown to be as effective and to have fewer adverse reactions in preterm infants . If equally effective, then oral ibuprofen for PDA closure would have several important advantages over the intravenous route . This study was designed to determine whether oral ibuprofen treatment is efficacious and safe in closure of a PDA in premature infants with respiratory distress syndrome . METHODS: Twenty-two preterm newborns (gestational age: 27.5 +/- 1.75 {range: 23.9-31 weeks}; weight: 979 +/- 266 {range: 380-1500 g}) with PDA and respiratory distress syndrome were studied prospectively . They received oral ibuprofen suspension 10 mg/kg/body weight for the first dose, followed at 24-hour intervals by 2 additional doses of 5 mg/kg each, if needed, starting on the second day of life . Echocardiography was performed before treatment and 24 hours after each dose . Every child underwent cranial ultrasonography before and after each ibuprofen dose . The rate of ductal closure, the need for additional treatment, side effects, complications, and the infants' clinical courses were recorded . RESULTS: Ductal closure was achieved in all newborns except for 1 (95.5%), in whom clinically nonsignificant ductal shunting persisted . No infant required surgical ligation of the ductus . There was no reopening of the ductus after closure had been achieved . Fourteen newborns were treated with 1 dose of ibuprofen, 6 were treated with 2 doses, and the remaining 2 were treated with 3 doses . The survival rate at 1 month was 86.4% (19 of 22) . Three (13.6%) infants died from the following causes: 1 who was born at 24 weeks' gestation with a birth weight of 380 g died as a result of extreme prematurity complications, necrotizing enterocolitis, and low birth weight; 1 died as a result of Candida sepsis; and the third died as a result of Klebsiella sepsis . Intraventricular hemorrhage was observed in 7 infants . The classification was changed from grade 2 to grade 3 in 1 and from grade 0 to grade 1 or higher in 3 others . The rate of survival to discharge was 86.4% (19 of 22) . No bronchopulmonary dysplasia was observed in the study group, and there was no case of tendency to bleed . There were no significant differences in the levels of serum creatinine before and after treatment with oral ibuprofen . CONCLUSIONS: Oral ibuprofen suspension may be an effective and safe alternative for PDA closure in premature infants with PDA . However, larger comparative studies are warranted.

Cell Physiol Biochem, 2003, 13(5), 309 - 14
Phagocytosis and allogeneic T cell stimulation by cultured human osteoblast-like cells; Ruiz C et al.; BACKGROUND/AIMS: The antigen phenotype of human osteoblast-like cells suggests that they are related to other cellular populations and may also have immunologic functions in common . METHODS: Flow cytometry and transmission electron microscopy were used to show the phagocytotic activity of osteoblast-like cells in culture . The allogeneic stimulation of T cells by human osteoblast-like cells was determined by the measurement of T cell proliferation . RESULTS: We demonstrated in vitro that human osteoblast-like cells isolated from normal bone specimens obtained during mandibular osteotomy can phagocytose particles of different nature and size and can stimulate allogeneic T cells . Phagocytosis of microorganisms (E.coli, Klebsiella or C . albicans) was observed, although at a very low rate of activity in comparison with the phagocytosis of latex particles . CONCLUSION: Our results suggest that human osteoblast-like cells may perform immunologic functions and act as antigen presentation cells .

Br J Pharmacol, 2003 Nov, 140(5), 855 - 62
Impaired host defense to Klebsiella pneumoniae infection in mice treated with the PDE4 inhibitor rolipram; Soares AC et al.; The increase in levels of cAMP in leukocytes by selective inhibitors of PDE4 may result in reduction of inflammation, and may be useful in the treatment of pulmonary inflammatory disorders in humans . Here, we have assessed whether oral treatment with the prototype PDE4 inhibitor, rolipram, interfered with the antibacterial host response following pulmonary infection of mice with Klebsiella pneumoniae . K . pneumoniae infection induced a marked increase in the recruitment of neutrophils to the lungs and the production of proinflammatory cytokines and chemokines, including tumor necrosis factor-alpha (TNF-alpha) and keratinocyte-derived chemokine (KC), in bronchoalveolar (BAL) fluid and lung tissue . There were also detectable amounts of interleukin-10 (IL-10) and significant lethality . Treatment with rolipram (3-30 mg kg-1) was associated with earlier lethality and significant inhibition of the TNF-alpha production . This was associated with enhanced production of IL-10 in lung tissue of rolipram-treated animals . Rolipram treatment did not affect KC expression and the recruitment of neutrophils in the lung tissue . Over 70% of neutrophils that migrated into the BAL fluid following K . pneumoniae infection ingested bacteria . Treatment with rolipram inhibited the percentage of neutrophils undergoing phagocytosis of K . pneumoniae in a dose-dependent manner . Maximal inhibition (62%) occurred at doses equal to or greater than 10 mg kg-1 . Thus, treatment of mice with the PDE4 inhibitor rolipram is accompanied by earlier lethality, enhanced bacterial load and decreased capacity of the responding host to produce TNF-alpha and of neutrophils to phagocytose bacteria . It will be important to investigate whether the shown ability of PDE4 inhibitors to inhibit neutrophil phagocytosis and control experimental bacterial infection will translate into an inhibition of the ability of neutrophils to deal with infectious microorganisms in the clinical setting.

J Microbiol Immunol Infect, 2003 Sep, 36(3), 182 - 6
Association of antibiotic utilization measures and reduced incidence of infections with extended-spectrum beta-lactamase-producing organisms; Lan CK et al.; With the overuse of expanded-spectrum cephalosporins, especially ceftazidime, outbreaks of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae and Escherichia coli infections have been reported . In this prospective observational study, we demonstrated that the addition of piperacillin/tazobactam to the formulary and the restriction of ceftazidime were associated with a decrease in the percentage of ceftazidime-resistant isolates . When the use of ceftazidime decreased by 96.43%, and the use of piperacillin/tazobactam increased by over 50% during the 9-month study period, a concomitant decrease was found in the percentage of colonization and infection by ESBL-producing E . coli or K . pneumoniae in patients admitted to the intensive care unit . Results from this 9-month intervention study support the concept that levels of local and institutional use of ceftazidime are of substantial importance to the emergence and persistence of endemic ceftazidime-resistant K . pneumoniae.

Digestion, 2003, 68(2-3), 91 - 3 Epub 2003 Oct 24.
Spontaneous bacterial peritonitis in a patient with myxedema ascites; Alberti LE et al.; Ascites is uncommon in patients with hypothyroidism . Herein we describe an 84-year-old female patient with myxedema ascites that resolved completely with thyroid replacement medication . Bacteriological studies of the ascitic fluid revealed gram-negative rods which eventually proved to be Klebsiella pneumoniae treated successfully with antibiotics . Our review of the literature failed to reveal a previous case of myxedema ascites with concomitant subclinical spontaneous bacterial peritonitis .

Biochim Biophys Acta, 2003 Nov 3, 1652(1), 64 - 74
Localization of ligand-binding sites on human C1q globular head region using recombinant globular head fragments and single-chain antibodies; Kojouharova MS et al.; As a charge pattern recognition molecule, human C1q can bind a range of immunoglobulin and non-immunoglobulin ligands via its carboxy-terminal globular domain and activate the classical complement pathway . Each globular domain has a heterotrimeric organization, composed of the carboxy-terminal halves of one A (ghA), one B (ghB), and one C (ghC) chain . Recently, we have found that the recombinant forms of individual ghA, ghB and ghC bind differentially to IgG, IgM, gp41 peptide 601-613 of human immunodeficiency virus-1 (HIV-1), gp21 peptide 400-429 of human T cell lymphotrophic virus-I (HTLV-I), beta-amyloid peptide, and apoptotic cells, suggesting a modular organization of the globular domain . This paper examines the interaction of ghA, ghB and ghC with two known C1q ligands: Klebsiella pneumoniae porin OmpK36 and salivary agglutinin . In addition, we have used a panel of recombinant single-chain antibodies (scFv) specific for ghA, ghB and ghC in order to map sites on the heterotrimeric globular domain which are likely to interact with IgG1, IgG3, IgM, OmpK36, salivary agglutinin and gp41 loop peptide . The combined use of recombinant ghA, ghB, ghC and single-chain antibodies has revealed at least three ligand-binding sites on the globular domain of C1q: one is IgG- and OmpK36-specific, the second (IgM-binding site) is most likely overlapping with IgG/OmpK36 binding site, and the third (the gp41-binding site) seems to be located at the junction between the collagen and globular domains.

Antimicrob Agents Chemother, 2003 Nov, 47(11), 3610 - 2
Effect of parenteral antibiotic administration on establishment of intestinal colonization in mice by Klebsiella pneumoniae strains producing extended-spectrum beta-lactamases; Hoyen CK et al.; A mouse model was used to test the hypothesis that antibiotics with activity against anaerobes promote overgrowth of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae strains in stool . Subcutaneous clindamycin consistently promoted establishment of high-density colonization, whereas piperacillin-tazobactam, ceftriaxone, and ceftazidime promoted colonization only when a large inoculum and/or more resistant strain was administered.

Antimicrob Agents Chemother, 2003 Nov, 47(11), 3554 - 60
Extended-spectrum beta-lactamases in Klebsiella pneumoniae bloodstream isolates from seven countries: dominance and widespread prevalence of SHV- and CTX-M-type beta-lactamases; Paterson DL et al.; A huge variety of extended-spectrum beta-lactamases (ESBLs) have been detected during the last 20 years . The majority of these have been of the TEM or SHV lineage . We have assessed ESBLs occurring among a collection of 455 bloodstream isolates of Klebsiella pneumoniae, collected from 12 hospitals in seven countries . Multiple beta-lactamases were produced by isolates with phenotypic evidence of ESBL production (mean of 2.7 beta-lactamases per isolate; range, 1 to 5) . SHV-type ESBLs were the most common ESBL, occurring in 67.1% (49 of 73) of isolates with phenotypic evidence of ESBL production . In contrast, TEM-type ESBLs (TEM-10 type, -12 type, -26 type, and -63 type) were found in just 16.4% (12 of 73) of isolates . The finding of TEM-10 type and TEM-12 type represents the first detection of a TEM-type ESBL in South America . PER (for Pseudomonas extended resistance)-type beta-lactamases were detected in five of the nine isolates from Turkey and were found with SHV-2-type and SHV-5-type ESBLs in two of the isolates . CTX-M-type ESBLs (bla(CTX-M-2) type and bla(CTX-M-3) type) were found in 23.3% (17 of 73) of isolates and were found in all study countries except for the United States . We also detected CTX-M-type ESBLs in four countries where they have previously not been described-Australia, Belgium, Turkey, and South Africa . The widespread emergence and proliferation of CTX-M-type ESBLs is particularly noteworthy and may have important implications for clinical microbiology laboratories and for physicians treating patients with serious K . pneumoniae infections.

J Biol Chem, 2004 Jan 16, 279(3), 2242 - 53 Epub 2003 Oct 13.
The crystal structures of Klebsiella pneumoniae acetolactate synthase with enzyme-bound cofactor and with an unusual intermediate; Pang SS et al.; Acetohydroxyacid synthase (AHAS) and acetolactate synthase (ALS) are thiamine diphosphate (ThDP)-dependent enzymes that catalyze the decarboxylation of pyruvate to give a cofactor-bound hydroxyethyl group, which is transferred to a second molecule of pyruvate to give 2-acetolactate . AHAS is found in plants, fungi, and bacteria, is involved in the biosynthesis of the branched-chain amino acids, and contains non-catalytic FAD . ALS is found only in some bacteria, is a catabolic enzyme required for the butanediol fermentation, and does not contain FAD . Here we report the 2.3-A crystal structure of Klebsiella pneumoniae ALS . The overall structure is similar to AHAS except for a groove that accommodates FAD in AHAS, which is filled with amino acid side chains in ALS . The ThDP cofactor has an unusual conformation that is unprecedented among the 26 known three-dimensional structures of nine ThDP-dependent enzymes, including AHAS . This conformation suggests a novel mechanism for ALS . A second structure, at 2.0 A, is described in which the enzyme is trapped halfway through the catalytic cycle so that it contains the hydroxyethyl intermediate bound to ThDP . The cofactor has a tricyclic structure that has not been observed previously in any ThDP-dependent enzyme, although similar structures are well known for free thiamine . This structure is consistent with our proposed mechanism and probably results from an intramolecular proton transfer within a tricyclic carbanion that is the true reaction intermediate . Modeling of the second molecule of pyruvate into the active site of the enzyme with the bound intermediate is consistent with the stereochemistry and specificity of ALS.

J Korean Med Sci, 2003 Oct, 18(5), 758 - 60
Emphysematous prostatic abscess due to Klebsiella pneumoniae: report of a case and review of the literature; Bae GB et al.; Emphysematous prostatic abscess is a very rare form of prostatitis . Emphysematous prostatic abscess due to Klebsiella pneumoniae may have a poor prognosis according to a few previous reports . We report a rare case of successfully treated emphysematous prostatic abscess with cystitis due to Klebsiella pneumoniae in a 50-yr-old man with 15-yr history of diabetes mellitus . The patient was referred to the emergency room of our hospital . The KUB film revealed gas shadows in the lower pelvic area suggestive of emphysematous cystitis or emphysematous prostatic abscess . The gas was mainly occupying the prostate and was also seen in the bladder on pelvic CT . The patient was successfully treated with long-term antibiotic use and additional percutaneous drainage of the abscess . Emphysematous prostatic abscess may be misdiagnosed as emphysematous cystitis due to the similar location of gas shadows on radiography . Computerized tomography and transrectal ultrasonography are helpful in making the diagnosis of emphysematous prostatic abscess . Appropriate use of effective antibiotics with drainage of pus is the best treatment . This case emphasizes the importance of timely and accurate diagnosis followed by appropriate treatment in emphysematous prostatic abscess in diabetic patients.

J Korean Med Sci, 2003 Oct, 18(5), 756 - 7
Retroperitoneal abscess complicated by acupuncture: case report; Cho YP et al.; With acupuncture treatment becoming an increasingly popular analgesic, there have been increasing reports on its associated complications . Although pneumothorax is the most frequently reported injury caused by acupuncture needles, infectious complications may not be uncommon . Most infectious complications show less serious clinical manifestations than pneumothorax, but retroperitoneal or intraabdominal abscess caused by acupuncture may be much more serious conditions . We experienced a 56-yr-old male diabetic patient presenting with serious retroperitoneal abscess after acupuncture treatments . Emergency operative drainage with adequate antibiotic therapy was performed . Bacterial culture of blood and closed pus specimens recovered Klebsiella pneumoniae . In addition to application of better knowledge on anatomy, appropriate antiseptic practice by practitioners will reduce many serious complications associated with acupuncture.

Korean J Gastroenterol, 2003 Sep, 42(3), 226 - 31
{Clinical significance of Klebsiella pneumoniae in liver abscess}; Lim SW et al.; BACKGROUND/AIMS: Klebsiella pneumoniae (K . pneumoniae) has been emerging as the leading cause of liver abscess although the most common pathogen was Escherichia coli in the past . Our study was to clarify the significance of K . pneumoniae as a pathogen of pyogenic liver abscess . METHODS: We reviewed 157 cases of pyogenic liver abscess treated at Yeungnam University Hospital from 1996 to 2001 . They were classified into two groups: K . pneumoniae group and non-K . pneumoniae group . The clinical presentations, characteristics of liver abscess, laboratory findings and the results of bacteriological studies were compared . RESULTS: The K . pneumoniae group included 60 (60.6%) cases among 99 cases with positive culture . We found higher incidence of alcoholics (45.0%) or diabetes millitus (35.0%) in K . pneumoniae group . Cryptogenic cause (61.7%) was the most frequent portal entry in K . pneumoniae liver abscess . On the other hand, in non-K . pneumoniae group, the cause of portal entry was usually the secondary (23.1%) following biliary disease (61.5%) . Statistically, there was no significant difference in age, sex, symptom, characteristics of abscess, laboratory findings except total bilirubin level between the two groups . CONCLUSIONS: Liver abscess caused by K . pneumoniae has emerged as an important infectious disease with new clinical significance . When clinicians see pyogenic liver abscess in patients with alcoholics or diabetes millitus, K . pneumoniae should be considered first as a cause of liver abscess.

Biochemistry, 2003 Oct 14, 42(40), 11615 - 24
Site-directed sulfhydryl labeling of the oxaloacetate decarboxylase Na+ pump of Klebsiella pneumoniae: helix VIII comprises a portion of the sodium ion channel; Wild MR et al.; Helix VIII of the beta-subunit of the oxaloacetate decarboxylase of Klebsiella pneumoniae contains the functionally important residues betaN373, betaG377, betaS382, and betaR389 . Using a functional oxaloacetate decarboxylase mutant devoid of Cys residues in the beta-subunit, each amino acid residue in helix VIII was replaced individually with Cys . Structural and dynamic features of this region were studied by using site-directed sulfhydryl modification of 20 single-Cys replacement mutants with methanethiosulfonate (MTS) reagents in the absence or presence of Na(+) ions . The pattern of accessibility of the MTS reagents from the periplasmic side of helix VIII shows a periodicity which suggests that this region is alpha-helical . In particular, a water-accessible face comprising betaN373, betaG377, betaS382, betaM386, and betaV390 may be part of a Na(+) channel . Cys residues introduced in the cytoplasmically oriented part of helix VIII were accessible to three different water-soluble MTS compounds and therefore believed to be exposed to water on this side of the membrane . Most residues located in the upper part of helix VIII (residues betaN373-betaV381C) were protected by Na(+) ions for inactivation by the MTS reagents . The distinct results on accessibility toward the different MTS reagents obtained in the presence or absence of Na(+) ions may suggest a conformational change upon binding of Na(+) in this region . The betaR389C mutant had a reduced activity and a pH optimum at pH 9, which could be restored to a wild-type pH optimum of 6.5 and to a 400% gain in activity upon chemical modification with 2-aminoethyl methanethiosulfonate.

J Bacteriol, 2003 Oct, 185(20), 6025 - 31
DpiA binding to the replication origin of Escherichia coli plasmids and chromosomes destabilizes plasmid inheritance and induces the bacterial SOS response; Miller C et al.; The dpiA and dpiB genes of Escherichia coli, which are orthologs of genes that regulate citrate uptake and utilization in Klebsiella pneumoniae, comprise a two-component signal transduction system that can modulate the replication of and destabilize the inheritance of pSC101 and certain other plasmids . Here we show that perturbed replication and inheritance result from binding of the effector protein DpiA to A+T-rich replication origin sequences that resemble those in the K . pneumoniae promoter region targeted by the DpiA ortholog, CitB . Consistent with its ability to bind to A+T-rich origin sequences, overproduction of DpiA induced the SOS response in E . coli, suggesting that chromosomal DNA replication is affected . Bacteria that overexpressed DpiA showed an increased amount of DNA per cell and increased cell size-both also characteristic of the SOS response . Concurrent overexpression of the DNA replication initiation protein, DnaA, or the DNA helicase, DnaB-both of which act at A+T-rich replication origin sequences in the E . coli chromosome and DpiA-targeted plasmids-reversed SOS induction as well as plasmid destabilization by DpiA . Our finding that physical and functional interactions between DpiA and sites of replication initiation modulate DNA replication and plasmid inheritance suggests a mechanism by which environmental stimuli transmitted by these gene products can regulate chromosomal and plasmid dynamics.

Acad Emerg Med, 2003 Oct, 10(10), 1019 - 23
Prevention of descending pneumonia in rts with perflubron-delivered tobramycin; Dickson EW et al.; OBJECTIVES: Patients undergoing emergent endotracheal intubation are at increased risk for developing pneumonia . Although numerous strategies have been investigated to reduce ventilator-associated pneumonia (VAP), the incidence of VAP and its associated mortality remains high . This investigation tested the hypothesis that LiquiVent (Alliance Pharmaceutical, San Diego, CA-LV) delivered antibiotics (via spray-dried microspheres-SDM) would improve survival in a rat model of descending gram-negative pneumonia . METHODS: Wistar rats (n = 49) were randomized to receive prophylaxis with 1) . nothing (controls); 2) . intramuscular (IM) tobramycin, 3) . intratracheal LV plus SDM shells (vehicle), 4) . intratracheal LV plus SDM shells plus IM tobramycin, or 5) . intratracheal LV plus SDM containing 1 mg/kg of tobramycin . All interventions were given 24 hours before a bacterial challenge with 10(8) colony-forming units of intratracheal Klebsiella pneumoniae . Mortality at ten days was the sole outcome measure . Survival in individual groups was compared with controls by Fisher's exact test with Bonferroni correction for multiple comparisons . RESULTS: All animals in the control group died of pneumonia within ten days of bacterial inoculation (0% survival) . Prophylaxis with either IM tobramycin or SDM vehicle plus IM tobramycin provided no protection (0% survival) . This is in sharp contrast to the cohort receiving pretreatment with tobramycin-containing SDM delivered via LV, in which 60% of the animals survived to study completion (p < 0.05) . CONCLUSIONS: Prophylaxis with SDM containing antibiotics delivered in low-dose LV provided significant protection in a rat model of descending gram-negative pneumonia . These data support the hypothesis that perfluorocarbon-delivered intratracheal antimicrobials may be useful in the prevention of VAP.

Comp Med, 2003 Aug, 53(4), 397 - 403
Susceptibility of irradiated B6D2F1/J mice to Klebsiella pneumoniae administered intratracheally: a pulmonary infection model in an immunocompromised host; Keller CE et al.; Bacteria such as Klebsiella pneumoniae can invade and colonize an immunocompromised host and complicate clinical recovery . In the study reported here, an experimental model of induced pneumonia was developed in 60Co gamma-photon-irradiated mice for the purpose of evaluating efficacy of therapeutic agents . The model was characterized by use of probit analysis of bacterial dose, and microbiologic, and histopathologic results . Bacterial colony-forming-unit (CFU) values producing 50% mortality within 30 days (LD50/30) and their 95% confidence intervals were 4.0 x 10(4) {1.7 x 10(4) - 8.9 x 10(4)} for 0-Gray (Gy)-irradiated mice, 1.9 x 10(4) {7.0 x 10(3) - 4.8 x 10(4)} for 5-Gy-irradiated mice, and 1.0 x 10(3) {2.8 x 10(2) - 3.3 x 10(3)} for 7-Gy-irradiated mice . Probit regression line fits calculated by use of an iterative, weighted least-squares fit, were used to assess a dose-modifying factor (DMF) . The DMFs for mortality, compared with that for the 0-Gy dose, with their 95% confidence intervals, were 2.2 {0.63 - 7.7} for the 5-Gy and 38.9 {9.6 -165.0} for 7-Gy doses . The 5-Gy probit line did not significantly differ (P = 0.21) from the 0-Gy probit line (dose ratios did not significantly differ from 1), whereas the 7-Gy probit line differed significantly from the 0-Gy probit line (P < 0.001) . These results demonstrate that 7-Gy 60Co gamma-photon radiation in combination with intratracheal K . pneumoniae challenge induces a valid pulmonary infection model in immunocompromised female B6D2F1/J mice.

Chembiochem, 2003 Oct 6, 4(10), 1049 - 56
Antisense inhibition of Escherichia coli RNase P RNA: mechanistic aspects; Gruegelsiepe H et al.; The ribonucleoprotein enzyme RNase P catalyzes endonucleolytic 5'-maturation of tRNA primary transcripts in all domains of life . The indispensability of RNase P for bacterial cell growth and the large differences in structure and function between bacterial and eukaryotic RNase P enzymes comply with the basic requirements for a bacterial enzyme to be suitable as a potential novel drug target . We have identified RNA oligonucleotides that start to show an inhibitory effect on bacterial RNase P RNAs of the structural type A (for example, the Escherichia coli or Klebsiella pneumoniae enzymes) at subnanomolar concentrations in our in vitro precursor tRNA (ptRNA) processing assay . These oligonucleotides are directed against the so-called P15 loop region of RNase P RNA known to interact with the 3'-CCA portion of ptRNA substrates . Lead probing experiments demonstrate that a complementary RNA or DNA 14-mer fully invades the P15 loop region and thereby disrupts local structure in the catalytic core of RNase P RNA . Binding of the RNA 14-mer is essentially irreversible because of a very low dissociation rate . The association rate of this oligonucleotide is on the order of 10(4) M(-1) s(-1) and is thus comparable to those of many other artificial antisense oligonucleotides . The remarkable inhibition efficacy is attributable to the dual effect of direct interference with substrate binding to the RNase P RNA active site and induction of misfolding of the catalytic core of RNase P RNA . Based on our findings, the P15 loop region of bacterial RNase P RNAs of the structural type A can be considered the "Achilles' heel" of the ribozyme and therefore represents a promising target for combatting multiresistant bacterial pathogens.

Int J Antimicrob Agents, 2003 Oct, 22(4), 367 - 73
Clinically significant borderline resistance of sequential clinical isolates of Klebsiella pneumoniae; Wagenlehner FM et al.; Two sequential clinical isolates of Klebsiella pneumoniae (Kpn) were isolated from bronchoalveolar lavage fluid (Kpn#1) and sputum (Kpn#2) of a patient with pneumonia, complicated by anatomical and immunosuppressive problems due to Wegener's granulomatosis . Despite 4 weeks of systemic treatment with ciprofloxacin (CIP) Kpn#2 was isolated thereafter . A fluoroquinolone-resistant mutant (Kpn#1-SEL) was derived from Kpn#1 in vitro by selecting on agar plates supplemented with ofloxacin . Kpn#1, Kpn#1-SEL and Kpn#2 had an identical pattern in PFGE . CIP MICs were 0.25, 2 and 4 mg/l for Kpn#1, Kpn#2 and Kpn#1-SEL, respectively . Kpn ATCC 10031 (CIP MIC 0.002 mg/l) served as control . We analyzed mechanisms of fluoroquinolone resistance by determining antibiotic susceptibility, organic solvent tolerance, accumulation of fluoroquinolones, dominance testing with wild-type topoisomerase genes (gyrA/B, parC/E), sequencing of the quinolone resistance determining regions of gyrA/B, parC/E and marR and Northern blotting of marR and acrAB genes . Compared with Kpn ATCC 10031, elevated MICs to fluoroquinolones and unrelated antibiotics in Kpn#1 was presumably due to a primary efflux pump other than AcrAB and increased the CIP MIC 125-fold . Although Kpn#1 tested sensitive according to NCCLS breakpoints, the elevated CIP MIC of 0.25 mg/l presumably rendered this isolate clinically resistant and lead to therapeutic failure in this case . Further increase of MIC to fluoroquinolones in vivo and in vitro was distinct . Kpn#1-SEL, selected in vitro, acquired a GyrA target mutation, whereas in Kpn#2 no known resistance mechanism could be detected.

Prostaglandins Other Lipid Mediat, 2003 Jul, 71(3-4), 131 - 45
Prolonged lipopolysaccharide inhibits leukotriene synthesis in peritoneal macrophages: mediation by nitric oxide and prostaglandins; Brock TG et al.; Resident rat peritoneal macrophages synthesize a variety of prostanoids and leukotrienes from arachidonic acid . Overnight treatment with lipopolysaccharide (LPS) induces the synthesis of cyclooxygenase-2 (COX-2) and an altered prostanoid profile that emphasizes the preferential conversion of arachidonic acid to prostacyclin and prostaglandin E2 . In these studies, we report that exposure to LPS also caused a strong suppression of 5-lipoxygenase but not 12-lipoxygenase activity, indicated by the inhibition of synthesis of both leukotriene B4 and 5-hydroxyeicosatetraenoic acid (5-HETE), but not of 12-HETE . Inhibition of 5-lipoxygenase activity by LPS was both time- and dose-dependent . Treatment of macrophages with prostaglandin E2 partially inhibited leukotriene synthesis, and cyclooxygenase inhibitors partially blocked the inhibition of leukotriene generation in LPS-treated cells . In addition to COX-2, nitric oxide synthase (NOS) was also induced by LPS . Treatment of macrophages with an NO donor mimicked the ability of LPS to significantly reduce leukotriene B4 synthesis . Inhibition of NOS activity in LPS-treated cells blunted the suppression of leukotriene synthesis . Inhibition of both inducible NOS and COX completely eliminated leukotriene suppression . Finally, macrophages exposed to prolonged LPS demonstrated impaired killing of Klebsiella pneumoniae and the combination of NOS and COX inhibitors restored killing to the control level . These results indicate that prolonged exposure to LPS severely inhibits leukotriene production via the combined action of COX and NOS products . The shift in mediator profile, to one that minimizes leukotrienes and emphasizes prostacyclin, prostaglandin E2 and NO, provides a signal that reduces leukocyte function, as indicated by impaired killing of Gram-negative bacteria.

Indian J Med Sci, 2003 Feb, 57(2), 68 - 70
Characterisation, biotyping, antibiogram and klebocin typing of Klebsiella with special reference to Klebsiella oxytoca; Aggarwal A et al.; 400 strains of Klebsiellae identified by culture characteristics and biochemical reactions were subjected to biotyping, antibiogram and klebocin typing . Based on indole production, pectin and gelatin liquefaction 16.0% of all the isolates were Klebsiella oxytoca . Maximum sensitivity was shown to Amikacin (72%) and maximum resistance to Ampicillin (87.5%) . Klebocin typability was 73.5% . So by combining biotyping, antibiogram and Klebocin typing, Klebsiella could be differentiated better than based on any single marker.

APMIS, 2003 Sep, 111(9), 857 - 66
Patterns of mutations in target genes in septicemia isolates of Escherichia coli and Klebsiella pneumoniae with resistance or reduced susceptibility to ciprofloxacin; Fendukly F et al.; Thirty-two Escherichia coli and 21 Klebsiella pneumoniae septicemia isolates with varying degrees of resistance to ciprofloxacin were analyzed for the presence of point mutations within the quinolone-resistance target genes . The number of mutations observed in the resistant isolates agreed with the level of ciprofloxacin resistance in both species . Such isolates were also resistant to nalidixic acid . Isolates with borderline susceptibility to ciprofloxacin, on the other hand, behaved differently in the two species . In E . coli all the isolates harbored at least one mutation and these isolates were also resistant to nalidixic acid, while no mutations were detected in the K . pneumoniae isolates, and susceptibility to nalidixic acid was unpredictable . Therefore, nalidixic acid cannot be used as a class representative . Time-kill curve studies on an isolate with borderline susceptibility from each species showed higher degrees of resistance to ciprofloxacin in comparison to that of the wild-type E . coli . A previously unreported parC mutation, S57-->T, was detected in a resistant E . coli isolate and might expand the QRDR of this gene . Normalized resistance interpretations of histograms confirmed the setting of microbiological zone breakpoints for ciprofloxacin testing.

J AOAC Int, 2003 Jul-Aug, 86(4), 669 - 74
Comparison between a bioassay and liquid chromatography-fluorescence-mass spectrometry(n) for the determination of incurred enrofloxacin in whole eggs; Donoghue DJ et al.; The objective of this study was to compare a bioassay with a liquid chromatography-fluorescence-mass spectrometry(n) method for detection of enrofloxacin (ENRO) in incurred eggs . The bioassay developed by our laboratories involves an agar diffusion microbiological method using Klebsiella pneumoniae as an indicator organism . Results demonstrate that both methods are capable of detecting incurred fluoroquinolone residues in eggs . During the 3-day dosing period of hens (Days 1-3) and following drug withdrawal (Days 5, 7, and 9), both of these methods were able to detect incurred ENRO in eggs above the zero tolerance established by the U.S . Food and Drug Administration . The LC-fluorescence-MS(n) method has the benefit of providing confirmation for fluoroquinolones, while the bioassay may be used as an effective, rapid screening method for detection of fluoroquinolone residues in eggs.

Antimicrob Agents Chemother, 2003 Oct, 47(10), 3332 - 5
Role of Klebsiella pneumoniae OmpK35 porin in antimicrobial resistance; Domenech-Sanchez A et al.; OmpK35 from Klebsiella pneumoniae is the homologue of Escherichia coli OmpF porin . Expression of OmpK35 in K . pneumoniae strain CSUB10R (lacking both OmpK35 and OmpK36) decreased the MICs of cephalosporins and meropenem > or = 128-fold and decreased the MICs of imipenem, ciprofloxacin, and chloramphenicol > or = 8-fold . MIC reductions by OmpK35 were 4 times (cefepime), 8 times (cefotetan, cefotaxime, and cefpirome), or 128 times (ceftazidime) higher than those caused by OmpK36, but the MICs were similar or 1 dilution lower for other evaluated agents.

Shock, 2003 Oct, 20(4), 309 - 15
Anti-tumor necrosis factor-alpha therapy during murine Klebsiella pneumoniae bacteremia: increased mortality in the absence of liver injury; Moore TA et al.; Klebsiella pneumoniae is a leading cause of gram-negative bacterial pneumonia, often resulting in bacteremia concurrent with the localized pulmonary infection . The beneficial role of tumor necrosis factor (TNF)-alpha during pulmonary infection has been well documented; however, consequences of TNF-alpha production during systemic bacterial infection are controversial . A murine model of K . pneumoniae was developed to address this important issue . Liver-associated TNF-alpha mRNA was induced within 30 min after intravenous bacterial inoculation and remained elevated through 6 h before returning to near-baseline at 24 h postinfection . Intravenous K . pneumoniae infection induced liver cellular injury that was completely ablated when mice were pretreated with a neutralizing anti-TNF-alpha antibody . Interestingly, this reduction in liver injury failed to translate into improved survival . Mice receiving anti-TNF-alpha continued to succumb to the infection even out to day 10 postinfection . Bacterial clearance after TNF-alpha neutralization was significantly impaired at later time points during infection . Correlating with impaired bacterial clearance was diminished production of liver-associated MIP-2, MIP-1alpha, MCP-1, and interferon-gamma . Further evidence of diminished antibacterial immune responses was noted when the activational status of splenic natural killer cells in anti-TNF-alpha-treated mice was examined 24 h postinfection . Natural killer cells displayed decreased CD69 expression . Combined, these data indicate that the beneficial effects of TNF-alpha during systemic K . pneumoniae infection outweigh the detrimental effects of TNF-alpha-mediated hepatocyte cellular injury . Anti-TNF-alpha therapy, although preventing liver injury during blood-borne bacterial infection, results in a dampened anti-bacterial host response, resulting in decreased bacterial clearance and overall survival.

J Perinatol, 2003 Sep, 23(6), 439 - 43
Extended spectrum beta lactamase-producing Klebsiella pneumoniae infections: a review of the literature; Gupta A et al.; Infections caused by extended-spectrum beta-lactamase (ESBL)-producing pathogens, particularly Klebsiella pneumoniae, are increasing . The epidemiology of ESBL-producing K . pneumoniae, the mechanisms of resistance, and treatment strategies for infections caused by these organisms are reviewed.

J Bacteriol, 2003 Oct, 185(19), 5882 - 90
A novel outer membrane protein, Wzi, is involved in surface assembly of the Escherichia coli K30 group 1 capsule; Rahn A et al.; Escherichia coli group 1 K antigens form a tightly associated capsule structure on the cell surface . Although the general features of the early steps in capsular polysaccharide biosynthesis have been described, little is known about the later stages that culminate in assembly of a capsular structure on the cell surface . Group 1 capsule biosynthesis gene clusters (cps) in E . coli and Klebsiella pneumoniae include a conserved open reading frame, wzi . The wzi gene is the first of a block of four conserved genes (wzi-wza-wzb-wzc) found in all group 1 K-antigen serotypes . Unlike wza, wzb, and wzc homologs that are found in gene clusters responsible for production of exopolysaccharides (i.e., predominantly cell-free polymer) in a range of bacteria, wzi is found only in systems that assemble capsular polysaccharides . The predicted Wzi protein shows no similarity to any other known proteins in the databases, but computer analysis of Wzi predicted a cleavable signal sequence . Wzi was expressed with a C-terminal hexahistidine tag, purified, and used for the production of specific antibodies that facilitated localization of Wzi to the outer membrane . Circular dichroism spectroscopy indicates that Wzi consists primarily of a beta-barrel structure, and dynamic light scattering studies established that the protein behaves as a monomer in solution . A nonpolar wzi chromosomal mutant retained a mucoid phenotype and remained sensitive to lysis by a K30-specific bacteriophage . However, the mutant showed a significant reduction in cell-bound polymer, with a corresponding increase in cell-free material . Furthermore, examination of the mutant by electron microscopy showed that it lacked a coherent capsule structure . It is proposed that the Wzi protein plays a late role in capsule assembly, perhaps in the process that links high-molecular-weight capsule to the cell surface.

Biomacromolecules, 2003 Sep-Oct, 4(5), 1372 - 9
Structure and properties of a bacterial polysaccharide from a Klebsiella strain (ATCC 12657); Guetta O et al.; The chemical structure and the rheological behavior of the Klebsiella polysaccharide ATCC 12657 was studied and compared with data described in the literature and obtained for similar polysaccharides . The acetylated polysaccharide presents in solution a normal viscoelastic behavior with no evidence of an ordered conformation whatever the experimental conditions are . The deacetylated form can induce the formation of physical gels, in the presence of salt excess or ethanol . Microcalorimetry, optical rotation, and rheology experiments demonstrate that a thermally reversible and highly cooperative conformational transition occurs at the same temperature than a sol-gel transition . The melting of the gel and the conformational transition temperatures are dependent on the nature of cations and ionic concentration, whereas the gel strength is only influenced by polymer concentration.

Microb Drug Resist, 2003 Fall, 9(3), 265 - 71
The roles of mutations in gyrA, parC, and ompK35 in fluoroquinolone resistance in Klebsiella pneumoniae; Chen FJ et al.; In a survey of 541 Klebsiella pneumoniae isolates from 44 hospitals in Taiwan, three distinct populations were identified by the disk diffusion method according to the disribution of zone diameters of ciprofloxacin . Isolates with resistant, reduced-susceptible, and susceptible to fluoroquinolone were defined as CIP zone diameters of < or = 15 mm, 16-26 mm, and > or = 27 mm, respectively . Thus, in addition to 38 (7%) resistant isolates, there were 30 (5.5%) reduced-susceptible isolates and 473 (87.5%) susceptible isolates . A total of 34 isolates consisting of nine resistant, 13 reduced-susceptible, and 12 susceptible isolates were assessed for point mutations in gyrA and parC and the outer membrane profiles . The susceptibility to fluoroquinolone of 13 reduced-susceptible isolates was not altered in the presence of carbonyl cyanide m-chlorophenylhydrazone, an efflux inhibitor, showing that efflux is not a major contributor to reduced susceptibility . In addition to single mutation in gyrA, OmpK35 porin loss can also be the first step for developing fluoroquinolone resistance . No strain possesses a parC mutation without the simultaneous presence of a gyrA mutation, suggesting that mutations in parC play a complementary role for higher-level of fluoroquinolone resistance and fluoroquinolone resistance is a multistep process.

Indian Pediatr, 2003 Aug, 40(8), 784 - 5
Pulmonary gangrene complicating bacterial pneumonia; Kothari PR et al.; Two cases of pulmonary gangrene involving left lower lobe in an 18-month and 4-year-old female children are reported . The patients looked like having empyema following Klebsiella pneumonia . The diagnosis was made following computerized tomography scan and during decortication respectively.

J Antimicrob Chemother, 2003 Oct, 52(4), 703 - 6 Epub 2003 Sep 01.
Detection of the plasmid-mediated quinolone resistance determinant qnr among clinical isolates of Klebsiella pneumoniae producing AmpC-type beta-lactamase; Rodriguez-Martinez JM et al.; OBJECTIVES: Plasmid pMG252 contains the qnr locus, which is responsible for low-level resistance to quinolones by protecting the DNA gyrase . pMG252 also encodes the AmpC-type beta-lactamase (pACBL), FOX-5 . The aim of this study was to determine the prevalence of qnr in strains from different geographical locations in America and Europe . METHODS: Four hundred and twenty-five (159 Klebsiella pneumoniae and 266 Escherichia coli) clinical isolates were studied . The detection of qnr was by PCR using specific primers for an internal fragment of 543 bp . RESULTS: qnr was detected in three cefoxitin-resistant K . pneumoniae strains, which also produced a pACBL . None of the E . coli isolates tested contained qnr . The three qnr-positive K . pneumoniae came from the USA, and all transferred a conjugative plasmid coding for cefoxitin resistance to E . coli J53 . qnr was also transferred by the same plasmid in two out of the three strains . The sequences of amplified qnr fragments from the three strains were identical to the qnr sequence from pMG252 . CONCLUSIONS: The qnr determinant is uncommon among clinical isolates of K . pneumoniae and E . coli, but its identification in three pACBL+ K . pneumoniae from the USA indicates the emergence of this quinolone resistance mechanism.

Infect Control Hosp Epidemiol, 2003 Aug, 24(8), 601 - 6
Attributable costs and length of stay of an extended-spectrum beta-lactamase-producing Klebsiella pneumoniae outbreak in a neonatal intensive care unit; Stone PW et al.; OBJECTIVES: To determine the costs of the interventions aimed at controlling the 4-month outbreak and to determine the attributable length of stay (LOS) associated with infection and colonization with extended-spectrum beta-lactamase-producing Klebsiella pneumoniae . DESIGN: A retrospective cost analysis was conducted from the hospital perspective . A micro-costing approach was employed . The LOS of four groups of hospitalized patients were compared with each other . National Perinatal Information Center criteria were used to stratify infants for severity of risk . The LOS of each group was compared with that of a national sample of similarly stratified infants . SETTING: A level III-IV, 45-bed neonatal intensive care unit . PATIENTS: Infant groups were infected (n = 8), colonized (n = 14), concurrent cohort (n = 54), and prior cohort (n = 486) . RESULTS: The cost of the outbreak totaled 341,751 dollars . The largest proportion of costs was related to healthcare worker time providing direct patient care (2,489 hours at a cost of 146,331 dollars) . Infected and colonized neonates had longer LOS than either the concurrent cohort or the prior cohort (P < .001) . Compared with the national sample, infected infants had a 48.5-day longer mean LOS (95% confidence interval {CI95}, 1.7 to 95.2), whereas the prior cohort's mean LOS was 6 days shorter (CI95, -9.4 to -2.9) . CONCLUSIONS: This study increases the understanding of the burden of these multidrug-resistant organisms . Further research is needed to estimate the societal costs of these infections and the cost-effectiveness of preventive interventions.

Antimicrob Agents Chemother, 2003 Sep, 47(9), 2938 - 45
Insertion sequence ISEcp1B is involved in expression and mobilization of a bla(CTX-M) beta-lactamase gene; Poirel L et al.; The genetic structures (ca . 10-kb DNA fragment) surrounding the plasmid-borne extended-spectrum beta-lactamase bla(CTX-M-19) gene in a Klebsiella pneumoniae clinical isolate were determined . This beta-lactamase gene was part of a 4,797-bp transposon inserted inside orf1 of Tn1721 . Inside this transposon, bla(CTX-M-19) was bracketed upstream and downstream by insertion sequences ISE cp1B and IS903D, respectively, and further downstream by a truncated gene encoding an outer membrane protein for iron transport . The single-copy ISEcp1B element was probably involved alone in the mobilization process that led to a 5-bp duplication at the target site of the transposed fragment . This mobilization event probably involved one inverted repeat of ISE cp1B and a second sequence farther away, resembling its second inverted repeat . Additionally, ISEcp1B provided -35 and -10 promoter sequences, contributing to the high-level expression of the bla(CTX-M-19) gene . Southern blot analysis failed to identify a reservoir of ISEcp1-like sequences among a series of gram-negative and gram-positive bacterial species usually found in the skin and intestinal human floras . The ability of ISEcp1-like elements to mobilize and to promote the expression of beta-lactamase genes may explain, in part, the current spread of CTX-M-type enzymes worldwide.

Antimicrob Agents Chemother, 2003 Sep, 47(9), 2922 - 8
New Klebsiella oxytoca beta-lactamase genes bla(OXY-3) and bla(OXY-4) and a third genetic group of K oxytoca based on bla(OXY-3); Granier SA et al.; The two genetic groups (oxy-1 and oxy-2) previously identified in the Klebsiella oxytoca taxon are recognizable by four independent molecular markers: (i) . ERIC-1R profiles, (ii) . 16S ribosomal DNA (rDNA) signature sequences, (iii) . singular nucleotides in a defined fragment of the rpoB gene, and (iv) the type of the strain's bla(OXY) gene (i.e., bla(OXY-1) or bla(OXY-2)) . K . oxytoca strains SG266 and SG271 could not be classified into these genetic groups based on their ERIC-1R profile and bla(OXY) gene sequence . With regard to the gene identity percentages between the bla(OXY-1) and bla(OXY-2) gene groups (86.8% +/- 0.4%) and within a bla(OXY) gene group (>99%), it was concluded that the bla(OXY) gene of strain SG271 was representative of a new bla(OXY) gene group (bla(OXY-3)), since the mean identity percentages between it and the two bla(OXY) gene groups were 85.5% +/- 0.2% and 84.4% +/- 0.4%, respectively . Since the corresponding percentages were 95.0% +/- 0.4% and 86.2% +/- 0.3% for strain SG266, it was impossible to classify its bla(OXY) gene, which was therefore named bla(OXY-4) . The 16S rDNA signature sequences of the two strains could be determined only after cloning experiments . The SG266 clones displayed the same signature sequence as that of the genetic group oxy-1, whereas the SG271 clones displayed three different 16S rDNA signature sequences that also differed from those of the two genetic groups . Singular nucleotides were found within the rpoB sequence of the two strains, allowing for their distinction from the two genetic groups . All of these results, combined with those previously obtained by the ERIC-1R PCR method, indicate that strain SG271 is representative of a new K . oxytoca genetic group (oxy-3), whereas strain SG266 could not be classified.

Antimicrob Agents Chemother, 2003 Sep, 47(9), 2831 - 7
Role of AcrR and ramA in fluoroquinolone resistance in clinical Klebsiella pneumoniae isolates from Singapore; Schneiders T et al.; The MICs of ciprofloxacin for 33 clinical isolates of K . pneumoniae resistant to extended-spectrum cephalosporins from three hospitals in Singapore ranged from 0.25 to >128 microg/ml . Nineteen of the isolates were fluoroquinolone resistant according to the NCCLS guidelines . Strains for which the ciprofloxacin MIC was >or=0.5 microg/ml harbored a mutation in DNA gyrase A (Ser83-->Tyr, Leu, or IIe), and some had a secondary Asp87-->Asn mutation . Isolates for which the MIC was 16 microg/ml possessed an additional alteration in ParC (Ser80-->IIe, Trp, or Arg) . Tolerance of the organic solvent cyclohexane was observed in 10 of the 19 fluoroquinolone-resistant strains; 3 of these were also pentane tolerant . Five of the 10 organic solvent-tolerant isolates overexpressed AcrA and also showed deletions within the acrR gene . Complementation of the mutated acrR gene with the wild-type gene decreased AcrA levels and produced a two- to fourfold reduction in the fluoroquinolone MICs . None of the organic solvent-tolerant clinical isolates overexpressed another efflux-related gene, acrE . While marA and soxS were not overexpressed, another marA homologue, ramA, was overexpressed in 3 of 10 organic solvent-tolerant isolates . These findings indicate that multiple target and nontarget gene changes contribute to fluoroquinolone resistance in K . pneumoniae . Besides AcrR mutations, ramA overexpression (but not marA or soxS overexpression) was related to increased AcrAB efflux pump expression in this collection of isolates.

Infect Immun, 2003 Sep, 71(9), 4891 - 900
Increased mortality and dysregulated cytokine production in tumor necrosis factor receptor 1-deficient mice following systemic Klebsiella pneumoniae infection; Moore TA et al.; A significant clinical complication of pulmonary infections with Klebsiella pneumoniae is peripheral blood dissemination, resulting in a systemic infection concurrent with the localized pulmonary infection . In this context, little is known about the role of tumor necrosis factor receptor 1 (TNFR1)-mediated innate immune responses during systemic Klebsiella infections . Mice lacking TNFR1 were significantly more susceptible to Klebsiella-induced mortality following intravenous inoculation . Bacterial clearance was impaired in TNFR1-deficient mice at early times following infection . Unexpectedly, bacterial burdens at the onset of mortality (days 2 to 3 postinfection) were not higher in mice lacking TNFR1 . However, elevated production of liver-associated proinflammatory cytokines (interleukin-12, tumor necrosis factor alpha {TNF-alpha{, and gamma interferon {IFN-gamma}) and chemokines (MIP-1 alpha, MIP-2, and MCP-1) was observed within the first 24 h of infection . Additionally, excessive plasma-associated IFN-gamma was also observed late in the course of infection (day 3) . Spleen cells from day-3 infected TNFR1-deficient mice secreted markedly enhanced levels of IFN-gamma when cultured in vitro . Additionally, there was a marked increase in the total number of activated lymphocyte subsets as indicated by CD69 upregulation . A notable exception was the sharp decrease in the frequency of splenic NK T cells in infected TNFR1 knockout (KO) mice . Anti-TNF-alpha therapy in TNFR1 KO mice significantly reduced chemokine production and liver injury . Combined, these data indicate a dysregulated antibacterial host response following intravenous Klebsiella infection in the absence of TNFR1 signaling, resulting in heightened cytokine production and hyperactivation of specific splenic lymphocyte subsets.

Biostatistics, 2001 Dec, 2(4), 433 - 44
Bayesian analysis of a time series of counts with covariates: an application to the control of an infectious disease; Hay JL et al.; This paper presents a Bayesian analysis of a time series of counts to assess its dependence on an explanatory variable . The time series represented is the incidence of the infectious disease ESBL-producing Klebsiella pneumoniae in an Australian hospital and the explanatory variable is the number of grams of antibiotic (third generation) cephalosporin used during that time . We demonstrate that there is a statistically significant relationship between disease occurrence and use of the antibiotic, lagged by three months . The model used is a parameter-driven model in the form of a generalized linear mixed model . Comparison of models is made in terms of mean square error.

Am J Clin Pathol, 2003 Aug, 120(2), 265 - 7
Cross-class resistance to non-beta-lactam antimicrobials in extended-spectrum beta-lactamase-producing Klebsiella pneumoniae; Procop GW et al.; Extended spectrum beta-lactamases are modified beta-lactamase enzymes that impart resistance to third-generation cephalosporins and make all beta-lactam antibiotics and cephalosporins useless for therapy . We compared the antimicrobial susceptibility profiles of extended-spectrum beta-lactamase (ESBL)-producing and non-ESBL-producing isolates of Klebsiella pneumoniae . The ESBL producers had significantly diminished susceptibility compared with the non-ESBL producers for gentamicin (P < .001), tobramycin (P < .001), amikacin (P < .005), trimethoprim-sulfamethoxazole (P < .01), ciprofloxacin (P < .001), and nitrofurantoin (P < .001) . All isolates were susceptible to imipenem . ESBL-producing K pneumoniae may also be resistant to non-beta-lactam antibiotics . Therefore, susceptibility testing of these isolates is critical for guiding therapy.

Clin Microbiol Infect, 2003 Jul, 9(7), 708 - 12
Antimicrobial activity against strains of Escherichia coli and Klebsiella spp . with resistance phenotypes consistent with an extended-spectrum beta-lactamase in Europe; Jones RN et al.; Extended-spectrum beta-lactamases (ESBLs) have continued to evolve after their initial detection in Europe nearly two decades ago . The summary results from the MYSTIC Program (31 medical centers) were utilized to assess the extent of ESBL occurrence in Europe from 1997 to 2000 . ESBL phenotype rates in Klebsiella spp . (32.8%) and Escherichia coli (14.4%) were generally stable, but extensive hospital-to-hospital and unit-to-unit variations were noted . The highest ESBL rates were found in eastern Europe (including Turkey) and in intensive care unit patient populations . Carbapenems remained active against the ESBL-producing strains (meropenem MIC90, 0.25-1 mg/L), while some other agents, such as aminoglycosides, fluoroquinolones, and piperacillin-tazobactam, were significantly less effective . International surveillance initiatives should be maintained to monitor future progression of this important resistance.

J Bacteriol, 2003 Sep, 185(17), 5240 - 7
Yeast two-hybrid studies on interaction of proteins involved in regulation of nitrogen fixation in the phototrophic bacterium Rhodobacter capsulatus; Pawlowski A et al.; Rhodobacter capsulatus contains two PII-like proteins, GlnB and GlnK, which play central roles in controlling the synthesis and activity of nitrogenase in response to ammonium availability . Here we used the yeast two-hybrid system to probe interactions between these PII-like proteins and proteins known to be involved in regulating nitrogen fixation . Analysis of defined protein pairs demonstrated the following interactions: GlnB-NtrB, GlnB-NifA1, GlnB-NifA2, GlnB-DraT, GlnK-NifA1, GlnK-NifA2, and GlnK-DraT . These results corroborate earlier genetic data and in addition show that PII-dependent ammonium regulation of nitrogen fixation in R . capsulatus does not require additional proteins, like NifL in Klebsiella pneumoniae . In addition, we found interactions for the protein pairs GlnB-GlnB, GlnB-GlnK, NifA1-NifA1, NifA2-NifA2, and NifA1-NifA2, suggesting that fine tuning of the nitrogen fixation process in R . capsulatus may involve the formation of GlnB-GlnK heterotrimers as well as NifA1-NifA2 heterodimers . In order to identify new proteins that interact with GlnB and GlnK, we constructed an R . capsulatus genomic library for use in yeast two-hybrid studies . Screening of this library identified the ATP-dependent helicase PcrA as a new putative protein that interacts with GlnB and the Ras-like protein Era as a new protein that interacts with GlnK.

Vaccine, 2003 Sep 8, 21(25-26), 3765 - 74
The outer membrane protein X from Escherichia coli exhibits immune properties; Maisnier-Patin K et al.; Outer membrane proteins (OMP) are expressed in Gram-negative bacterial cell wall . OmpA from Klebsiella pneumoniae (KpOmpA) has been shown to bind and to activate selectively antigen presenting cells (APCs), eliciting protective CTL responses . In this study, we investigated whether OmpX, another member of the OMP family and structurally related to OmpA, exhibits the same immune properties . Using recombinant OmpX from Escherichia coli (EcOmpX), we report that EcOmpX binds to and is internalized by human APCs . However, EcOmpX does not activate APCs . EcOmpX acts as an efficient carrier protein as it induces a potent and Th1/Th2 mixed anti-TNP humoral response . However, adjuvant is required to generate a protective anti-tumoral immune response in mice injected with a tumor model antigen coupled to EcOmpX . Collectively, these data show that EcOmpX is recognized by innate cells but does not activate them, suggesting that EcOmpX does not provide a signal danger to APCs . In conclusion, this study provides information on the molecular mechanisms involved in the recognition and activation of innate cells by bacterial outer membrane proteins.

J Appl Microbiol, 2003, 95(3), 521 - 7
Substrate induction of isomaltulose synthase in a newly isolated Klebsiella sp . LX3; Li X et al.; AIMS: Production of isomaltulose by newly isolated Klebsiella sp . LX3 . METHODS AND RESULTS: The bacterial isolate LX3, which transforms sucrose to isomaltulose and trehalulose, has been isolated from a soil sample in Singapore . Morphological and biochemical analysis, as well as 16s rRNA sequence demonstrated that the isolate could represent a new member of genus Klebsiella . The strain has several interesting features . The immobilized cells of Klebsiella sp . LX3 convert more than 99% of sucrose to products that consist of more than 87% of isomaltulose, 11.6% of trehalulose, and <1% of glucose . CONCLUSIONS: The production of isomaltulose synthase in isolate LX3 is inducible by its substrate sucrose and the sugars containing a fructofuranosyl group . SIGNIFICANCE AND IMPACT OF STUDY: It would be useful for future biotechnological applications to understand the structural features or motifs of the isomaltulose synthases that determine the sucrose conversion efficiency and the ratio of the conversion products.

Biochemistry, 2003 Aug 19, 42(32), 9789 - 96
Accessibility of cysteine residues in a cytoplasmic loop of CitS of Klebsiella pneumoniae is controlled by the catalytic state of the transporter; Sobczak I et al.; The citrate transporter CitS of Klebsiella pneumoniae is a secondary transporter that transports citrate in symport with two sodium ions and one proton . Treatment of CitS with the alkylating agent N-ethylmaleimide resulted in a complete loss of transport activity . Treatment of mutant proteins in which the five endogenous cysteine residues were mutated into serines in different combinations revealed that two cysteine residues located in the C-terminal cytoplasmic loop, Cys-398 and Cys-414, were responsible for the inactivation . Labeling with the membrane impermeable methanethiosulfonate derivatives MTSET and MTSES in right-side-out membrane vesicles showed that the cytoplasmic loop was accessible from the periplasmic side of the membrane . The membrane impermeable but more bulky maleimide AmdiS did not inactivate the transporter in right-side-out membrane vesicles . Inactivation by N-ethylmaleimide, MTSES, and MTSET was prevented by the presence of the co-ion Na(+) . Protection was obtained upon binding 2 Na(+), which equals the transport stoichiometry . In the absence of Na(+), the substrate citrate had no effect on the inactivation by permeable or impermeable thiol reagents . In contrast, when subsaturating concentrations of Na(+) were present, citrate significantly reduced inactivation suggesting ordered binding of the substrate and co-ion; citrate is bound after Na(+) . In the presence of the proton motive force, the reactivity of the Cys residues was increased significantly for the membrane permeable N-ethylmaleimide, while no difference was observed for the membrane impermeable thiol reagents . The results are discussed in the context of a model for the opening and closing of the translocation pore during turnover of the transporter.

Appl Microbiol Biotechnol, 2003 Dec, 63(2), 143 - 6 Epub 2003 Aug 08.
Microbial fed-batch production of 1,3-propanediol by Klebsiella pneumoniae under micro-aerobic conditions; Chen X et al.; The microbial production of 1,3-propanediol (1,3-PD) by Klebsiella pneumoniae under micro-aerobic conditions was investigated in this study . The experimental results of batch fermentation showed that the final concentration and yield of 1,3-PD on glycerol under micro-aerobic conditions approached values achieved under anaerobic conditions . However, less ethanol was produced under microaerobic than anaerobic conditions at the end of fermentation . The batch micro-aerobic fermentation time was markedly shorter than that of anaerobic fermentation . This led to an increment of productivity of 1,3-PD . For instance, the concentration, molar yield, and productivity of 1,3-PD of batch micro-aerobic fermentation by K . pneumoniae DSM 2026 were 17.65 g/l, 56.13%, and 2.94 g l(-1) h(-1), respectively, with a fermentation time of 6 h and an initial glycerol concentration of 40 g/l . Compared with DSM 2026, the microbial growth of K . pneumoniae AS 1.1736 was slow and the concentration of 1,3-PD was low under the same conditions . Furthermore, the microbial growth in fed-batch fermentation by K . pneumoniae DSM 2026 was faster under micro-aerobic than anaerobic conditions . The concentration, molar yield, and productivity of 1,3-PD in fed-batch fermentation under micro-aerobic conditions were 59.50 g/l, 51.75%, and 1.57 g l(-1) h(-1), respectively . The volumetric productivity of 1,3-PD under microaerobic conditions was almost twice that of anaerobic fed-batch fermentation, at 1.57 and 0.80 g l(-1) h(-1), respectively.

J Clin Microbiol, 2003 Aug, 41(8), 3893 - 6
VIM-1 Metallo-beta-lactamase-producing Klebsiella pneumoniae strains in Greek hospitals; Giakkoupi P et al.; Seventeen Klebsiella pneumoniae clinical isolates carrying the bla(VIM-1) metallo-beta-lactamase gene were collected in the intensive care units of three hospitals in Athens, Greece, in 2002 . They exhibited various carbapenem resistance levels (Etest MICs of imipenem ranged from 4 to 32 microg/ml) . All isolates gave positive results by the imipenem-EDTA synergy Etest . The isolates were classified into four main types by pulsed-field gel electrophoresis; the majority of the isolates (5 and 10 isolates) belonged to two types . The bla(VIM-1) gene cassette was part of the variable region of a class 1 integron that also included aac6, dhfrI, and aadA . This structure was carried by transferable plasmids.

Urol Int, 2003, 71(2), 226 - 7
Infected hydrocoele of the canal of Nuck in a neonate; Ameh EA et al.; Hydrocoele of the canal of Nuck is an uncommon presentation in the neonate and complications are rare . A 6-day-old girl presented with a right groin swelling from birth . The swelling remained static until age 3 days when it increased rapidly in size . There was no fever or gastrointestinal symptoms . Physical examination showed a large nontender mass extending from the right groin into the ipsilateral labium majus with distortion of the external genitalia . Needle aspiration yielded cloudy fluid, which gave a growth of Klebsiella on culture . A hydrocoele of the canal of Nuck was confirmed at surgery and was excised . Postoperative course was uneventful and there has been no recurrence at 2 years of follow-up .

Nucleic Acids Res, 2003 Aug 1, 31(15), 4345 - 53
Transposases are responsible for the target specificity of IS1397 and ISKpn1 for two different types of palindromic units (PUs); Wilde C et al.; Insertion sequences (IS)1397 and ISKpn1, found in Escherichia coli and Klebsiella pneumoniae, respectively, are IS3 family members that insert specifically into short palindromic repeated sequences (palindromic units or PUs) . In this paper, we first show that although PUs are naturally absent from extrachromosomal elements, both ISs are able to transpose from the chromosome or from a plasmid into PUs artificially introduced into target plasmids . We also show that ISKpn1 target specificity is restricted to K.pneumoniae Z1 PU type, whereas IS1397 target specificity is less stringent since the IS targets the three E.coli Y, Z1 and Z2 PU types indifferently . Experiments of transposition of both ISs driven by both transposases demonstrate that the inverted repeats flanking the ISs are not responsible for this target specificity, which is entirely due to the transposase itself . Implications on ISs evolution are presented.

Infect Control Hosp Epidemiol, 2003 Jul, 24(7), 495 - 500
Analysis of three outbreaks due to Klebsiella species in a neonatal intensive care unit; Ayan M et al.; OBJECTIVE: To investigate the clinical, microbiological, and epidemiologic features of three outbreaks caused by Klesiella during 3 years . SETTING: Neonatal intensive care unit of a university hospital . PATIENTS: Thirty affected neonates . METHODS: Data were collected through chart reviews and conversations with physicians . Screening samples were obtained from the staff, the neonates, and the environment . Antibiogram typing and arbitrarily primed polymerase chain reaction-based fingerprinting were used to type the strains . RESULTS: The first outbreak had 13 K . pneumoniae strains isolated . The second outbreak had 10 K . oxytoca strains isolated . The third outbreak had 20 K . pneumoniae strains isolated . More than half of the patients had low birth weights, were premature, and underwent mechanical ventilation and intravenous catheterization . Approximately three-fourths of the patients died . The isolates tested were completely susceptible to meropenem, cefoxitin, and ciprofloxacin and were resistant to cephalothin . More than half of these strains were resistant to many beta-lactam antibiotics, amikacin, and trimethoprim/sulfamethoxazole . Typing procedures yielded 3 antibiotypes and 3 genotypes among the isolates of the first outbreak, 3 antibiotypes with 1 subtype and 2 genotypes with 1 subtype in the second outbreak, and 2 antibiotypes and 2 genotypes in the third outbreak . CONCLUSIONS: Klebsiella outbreaks mainly affected premature neonates with intravenous catheters, mechanical ventilation, or both . The high mortality rate (76.7%) was notable . Resistance to multiple antibiotics, but mainly to broad-spectrum beta-lactam antibiotics, was observed, particularly in K . pneumoniae isolates . Molecular typing indicated that the three outbreaks were not related to one other.

Biophys J, 2003 Aug, 85(2), 876 - 85
CymA of Klebsiella oxytoca outer membrane: binding of cyclodextrins and study of the current noise of the open channel; Orlik F et al.; CymA, the outer membrane component of the cyclodextrin (CD) uptake and metabolism system of Klebsiella oxytoca, was reconstituted into lipid bilayer membranes . The channel properties of this unusual porin were studied in detail . The binding of CDs to the channel resulted in its complete block for ion transport . This result allowed the detailed investigation of carbohydrate binding, and the stability constants for the binding of cyclic and linear carbohydrates to the binding site inside the channel were calculated from titration experiments of the membrane conductance with the carbohydrates . Highest stability constant was observed for alpha-cyclodextrin (alpha-CD; K = 32,000 1/M) followed by beta-cyclodextrin (beta-CD; K = 1970 1/M) and gamma-cyclodextrin (gamma-CD; K = 310 1/M) . Linear maltooligosaccharides bound also to CymA but with much smaller stability constants as compared to cyclic ones . The noise of the current through CymA in multi- and single-channel experiments was investigated using fast Fourier transformation . The current through the open channels had a rather high spectral density, which was a Lorentzian function of the frequency up to 2000 Hz . Upon addition of cyclic dextrins to the aqueous phase the spectral density decreased in a dose-dependent manner, which made it impossible to evaluate the binding kinetics . Experiments with single CymA-channels demonstrated the channel is highly asymmetric concerning channel flickers and current noise.

Eur J Clin Microbiol Infect Dis, 2003 Aug, 22(8), 486 - 8 Epub 2003 Jul 18.
Community-acquired Klebsiella pneumoniae central nervous system infections in adults in Singapore; Habib AG et al.; A series of successfully managed community-acquired Klebsiella pneumoniae infections of the central nervous system (CNS) that occurred in six non-neurosurgical adult patients in Singapore over a 2-year period is reported . Three patients had abscesses that were drained, and three had meningitis; all were treated with third-generation cephalosporins . All six patients were middle-aged adults, three of whom were food handlers . Clinicians should be aware of Klebsiella pneumoniae as an important CNS pathogen, particularly in East Asia . Although third-generation cephalosporins have had a major impact on the outcome of Klebsiella pneumoniae CNS infections, the emergence of extended-spectrum beta-lactamase-producing strains may lead to their reduced efficacy in this clinical setting.

J Biol Chem, 2003 Oct 3, 278(40), 39189 - 96 Epub 2003 Jul 16.
The structure of the periplasmic ligand-binding domain of the sensor kinase CitA reveals the first extracellular PAS domain; Reinelt S et al.; The integral membrane sensor kinase CitA of Klebsiella pneumoniae is part of a two-component signal transduction system that regulates the transport and metabolism of citrate in response to its environmental concentration . Two-component systems are widely used by bacteria for such adaptive processes, but the stereochemistry of periplasmic ligand binding and the mechanism of signal transduction across the membrane remain poorly understood . The crystal structure of the CitAP periplasmic sensor domain in complex with citrate reveals a PAS fold, a versatile ligand-binding structural motif that has not previously been observed outside the cytoplasm or implicated in the transduction of conformational signals across the membrane . Citrate is bound in a pocket that is shared among many PAS domains but that shows structural variation according to the nature of the bound ligand . In CitAP, some of the citrate contact residues are located in the final strand of the central beta-sheet, which is connected to the C-terminal transmembrane helix . These secondary structure elements thus provide a potential conformational link between the periplasmic ligand binding site and the cytoplasmic signaling domains of the receptor.

J Immunol, 2003 Jul 15, 171(2), 955 - 63
Sublethal hyperoxia impairs pulmonary innate immunity; Baleeiro CE et al.; Supplemental oxygen is often required in the treatment of critically ill patients . The impact of hyperoxia on pulmonary host defense is not well-established . We hypothesized that hyperoxia directly impairs pulmonary host defense, beyond effects on alveolar wall barrier function . C57BL/6 mice were kept in an atmosphere of >95% O(2) for 4 days followed by return to room air . This exposure does not lead to mortality in mice subsequently returned to room air . Mice kept in room air served as controls . Mice were intratracheally inoculated with Klebsiella pneumoniae and followed for survival . Alveolar macrophages (AM) were harvested by bronchoalveolar lavage after 4 days of in vivo hyperoxia for ex vivo experiments . Mortality from pneumonia increased significantly in mice exposed to hyperoxia compared with infected mice in room air . Burden of organisms in the lung and dissemination of infection were increased in the hyperoxia group whereas accumulation of inflammatory cells in the lung was impaired . Hyperoxia alone had no impact on AM numbers, viability, or ability to phagocytize latex microbeads . However, following in vivo hyperoxia, AM phagocytosis and killing of Gram-negative bacteria and production of TNF-alpha and IL-6 in response to LPS were significantly reduced . AM surface expression of Toll-like receptor-4 was significantly decreased following in vivo hyperoxia . Thus sublethal hyperoxia increases Gram-negative bacterial pneumonia mortality and has a significant adverse effect on AM host defense function . Impaired AM function due to high concentrations of supplemental oxygen may contribute to the high rate of ventilator-associated pneumonia seen in critically ill patients.

Appl Environ Microbiol, 2003 Jul, 69(7), 3791 - 7
Construction of deoxyriboaldolase-overexpressing Escherichia coli and its application to 2-deoxyribose 5-phosphate synthesis from glucose and acetaldehyde for 2'-deoxyribonucleoside production; Horinouchi N et al.; The gene encoding a deoxyriboaldolase (DERA) was cloned from the chromosomal DNA of Klebsiella pneumoniae B-4-4 . This gene contains an open reading frame consisting of 780 nucleotides encoding 259 amino acid residues . The predicted amino acid sequence exhibited 94.6% homology with the sequence of DERA from Escherichia coli . The DERA of K . pneumoniae was expressed in recombinant E . coli cells, and the specific activity of the enzyme in the cell extract was as high as 2.5 U/mg, which was threefold higher than the specific activity in the K . pneumoniae cell extract . One of the E . coli transformants, 10B5/pTS8, which had a defect in alkaline phosphatase activity, was a good catalyst for 2-deoxyribose 5-phosphate (DR5P) synthesis from glyceraldehyde 3-phosphate and acetaldehyde . The E . coli cells produced DR5P from glucose and acetaldehyde in the presence of ATP . Under the optimal conditions, 100 mM DR5P was produced from 900 mM glucose, 200 mM acetaldehyde, and 100 mM ATP by the E . coli cells . The DR5P produced was further transformed to 2'-deoxyribonucleoside through coupling the enzymatic reactions of phosphopentomutase and nucleoside phosphorylase . These results indicated that production of 2'-deoxyribonucleoside from glucose, acetaldehyde, and a nucleobase is possible with the addition of a suitable energy source, such as ATP.

Zhonghua Bing Li Xue Za Zhi, 2003 Apr, 32(2), 142 - 6
{Changes of the actin and transforming growth factor-beta1 expression in the small airways of the rat with chronic obstructive lung disease}; Ge XN et al.; OBJECTIVE: To study the roles of actin and transforming growth factor (TGF)-beta(1) in the injury repair and the development of emphysema . METHODS: Wistar rats were randomly divided into two groups: the smoking and infection group (group SI) and the control group (group C) . The rats of group SI received smoking irritation accompanying with repeated intranasal infection . Subgroups of the experimental animals were killed in the 2nd, 4th, 8th and 16th weeks respectively . The morphological changes of lungs were compared and PaO(2), PaCO(2) as well as the right ventricular systolic pressure (RVSP) were analysed . The lung sections were stained with immunohistochemistry for actin and TGF-beta(1) . RESULTS: In comparison with animals of group C, thickening of the bronchiolar walls, narrowing of bronchiolar lumens, and area of emphysema were much severe in animals of group SI (P < 0.05) . The muscularization of intra-alveolar arteries in group SI in the 16th week was apparent in comparing with that in group C (P < 0.05) . PaO(2) values in group SI were significantly decreased, and RVSP values in group SI were significantly increased in the 8th and 16th week (P < 0.05) . Actin expression was increased in animals of group SI in the 4th and 8th week (0.24 +/- 0.06 and 0.25 +/- 0.05) in comparing with that of group C (0.09 +/- 0.03) (P < 0.05) . Animals of group SI showed a significant increase of TGF-beta(1) in lung tissue in different periods as mentioned in above (33.33 +/- 12.11, 45.71 +/- 15.12, 71.43 +/- 16.76 and 86.25 +/- 20.66 respectively) . CONCLUSIONS: The increased expression of actin and TGF-beta(1) protein in small airways induced by smoking irritation and Klebsiella Pneumoniae may interfere with the repair response, and contributes to the development of emphysema.

J Assoc Physicians India, 2003 Mar, 51, 306 - 8
Chronic Klebsiella pneumonia in an immunocompetent host; Sinha R et al.; A 55 years immunocompetent male was evaluated for chronic pulmonary disease of over 12-month duration for which he had twice been prescribed anti-tubercular therapy . Investigations led to the diagnosis of chronic Klebsiella pneumonia, which is rarely encountered in immunocompetent hosts in the antibiotic era.

Rev Argent Microbiol, 2003 Jan-Mar, 35(1), 1 - 7
{Broad-spectrum beta-lactamases in Klebsiella pneumoniae isolated at the Cordoba Children's Hospital, Argentina}; Saka HA et al.; The aim of the present study was to investigate the presence of extended-spectrum beta-lactamases (ESBL) in Klebsiella pneumoniae isolated at the "Hospital de Ninos de Cordoba" . The strains were collected from inpatients between January 1996 and July 2000 . A total of 150 ESBL producer isolates were detected . During 1996 the prevalence of ESBL producer K . pneumoniae was 20%, but since 1998 the values have increased to approximately 60% . Phenotypic analysis such as isoelectric point (pl) and antibiotyping performed in 32 randomly selected isolates showed two different enzyme profiles: 81% had ESBL with pl = 7.9 and preferential activity against cefotaxime, while 19% showed ESBL with pl = 5.4 and preferential activity against ceftazidime . No isolates resistant to imipenem or ciprofloxacin were detected . Susceptibility to other antimicrobial agents varied, but resistance to gentamicin was strongly associated with ESBL producer isolates . Resistance determinants could be transferred to Escherichia coli by conjugation assays.

Biotechnol Bioeng, 2003 Sep 5, 83(5), 525 - 36
Combined use of proteomic analysis and enzyme activity assays for metabolic pathway analysis of glycerol fermentation by Klebsiella pneumoniae; Wang W et al.; The fed-batch fermentation of glycerol to 1,3-propanediol by Klebsiella pneumoniae displayed an unusual dynamic behavior that can be clearly divided into four distinct phases according to cell growth and CO(2) evolution rate . Metabolism changed significantly during the different phases as reflected by the varied specific rates of substrate consumption and product formation . An assay of activities of the three initial enzymes of glycerol metabolism, namely glycerol dehydratase (GDHt), glycerol dehydrogenase (GDH), and 1,3-propanediol-oxidoreductase (PDOR), showed apparently different patterns of expression . To understand the culture dynamics and patterns of enzyme formation at a more systemic level we analyzed the expression patterns of intracellular proteins of K . pneumoniae from different phases of the fed-batch fermentation using two-dimensional gel electrophoresis (2DE) . Two new enzymes, namely a phosphoenolpyruvate-dependent dihydroxyacetone kinase (DHAK II) and a hypothetical oxidoreductase (HOR), which are directly related to glycerol metabolism and 1,3-propanediol formation, were identified among the highly expressed proteins . The changes in expression of these new enzymes and several other proteins identified from the 2DE analysis helped to understand not only the dynamic behavior of the fed-batch fermentation reported in this work but also some previously insufficiently understood phenomena related to this fermentation process . In particular, we demonstrated the combined use of proteomic analysis and enzyme activity assay data for metabolic pathway analysis and for a better identification of targets for bioprocess improvement .

Retina, 2003 Jun, 23(3), 366 - 70
Result of early vitrectomy for endogenous Klebsiella pneumoniae endophthalmitis; Yoon YH et al.; PURPOSE: To determine the role of pars plana vitrectomy (PPV) in the treatment of Klebsiella pneumoniae endogenous endophthalmitis . METHODS: Records of seven consecutive patients (10 eyes) diagnosed with Klebsiella endogenous endophthalmitis were retrospectively reviewed . RESULTS: Five patients (71%) had diabetes, and four (57%) had a liver abscess as the source . In most cases, the inflammation progressed within days and resulted in decreased vision worse than hand motions and a total vitreous abscess, despite systemic and intravitreal antibiotic injections . A PPV with subretinal abscess drainage and silicone oil tamponade was performed within 2 weeks . After 6 months, the retina remained attached in all eyes (100%), and vision was counting fingers or better in five eyes (50%) . Two eyes recovered visual acuity between 20/63 and 20/125 . CONCLUSIONS: Physicians should be alerted to the development of endogenous endophthalmitis in patients with Klebsiella septicemia, especially in diabetics with a hepatobiliary abscess . Aggressive therapy, including early vitrectomy with antibiotic injection, may improve the final outcome in this otherwise devastating ocular condition.

Antimicrob Agents Chemother, 2003 Jul, 47(7), 2242 - 8
Plasmid-mediated quinolone resistance in clinical isolates of Escherichia coli from Shanghai, China; Wang M et al.; Although quinolone resistance usually results from chromosomal mutations, recent studies indicate that quinolone resistance can also be plasmid mediated . The gene responsible, qnr, is distinct from the known quinolone resistance genes and in previous studies seemed to be restricted to Klebsiella pneumoniae and Escherichia coli isolates from the University of Alabama in Birmingham, where this resistance was discovered . In Shanghai, the frequency of ciprofloxacin resistance in E . coli has exceeded 50% since 1993 . Seventy-eight unique ciprofloxacin-resistant clinical isolates of E . coli from Shanghai hospitals were screened for the qnr gene by colony blotting and Southern hybridization of plasmid DNA . Conjugation experiments were done with azide-resistant E . coli J53 as a recipient with selection for plasmid-encoded antimicrobial resistance (chloramphenicol, gentamicin, or tetracycline) and azide counterselection . qnr genes were sequenced, and the structure of the plasmid DNA adjacent to qnr was analyzed by primer walking with a sequential series of outward-facing sequencing primers with plasmid DNA templates purified from transconjugants . Six (7.7%) of 78 strains gave a reproducible hybridization signal with a qnr gene probe on colony blots and yielded strong signals on plasmid DNA preparations . Quinolone resistance was transferred from all six probe-positive strains . Transconjugants had 16- to 250-fold increases in the MICs of ciprofloxacin relative to that of the recipient . All six strains contained qnr with a nucleotide sequence identical to that originally reported, except for a single nucleotide change (CTA-->CTG at position 537) encoding the same amino acid . qnr was located in complex In4 family class 1 integrons . Two completely sequenced integrons were designated In36 and In37 . Transferable plasmid-mediated quinolone resistance associated with qnr is thus prevalent in quinolone-resistant clinical strains of E . coli from Shanghai and may contribute to the rapid increase in bacterial resistance to quinolones in China.

Antimicrob Agents Chemother, 2003 Jul, 47(7), 2088 - 92
Extended-spectrum cephalosporin compared to cefazolin for treatment of Klebsiella pneumoniae-caused liver abscess; Cheng HP et al.; From January 1995 to May 2000, a total of 107 adults with liver abscess due to Klebsiella pneumoniae admitted at a large medical center in northern Taiwan were reviewed . Patients were considered to have received cefazolin or an extended-spectrum cephalosporin if they received at least 3 days of that antibiotic within the first 5 days of hospitalization . Fifty-nine (55.1%) patients received cefazolin, and 48 (44.9%) patients received an extended-spectrum cephalosporin . The demographic data, clinical features, severities of illness, and rates of early drainage for the two groups were comparable . However, the rates of developing complications for the two groups were significantly different (37.3 versus 6.3%, respectively; P < 0.001) . Furthermore, six independent factors preventing severe complications following liver abscess due to K . pneumoniae were identified: normal platelet count, alkaline phosphatase less than 300 U/liter, no gas formation in the abscess, APACHE III score less than 40, use of an extended-spectrum cephalosporin, and early drainage . In conclusion, cefazolin therapy may be suboptimal for patients with liver abscess due to K . pneumoniae despite active in vitro susceptibility . Use of an extended-spectrum cephalosporin and early drainage for patients with liver abscess due to K . pneumoniae are suggested.

J Biol Chem, 2003 Sep 12, 278(37), 35428 - 34 Epub 2003 Jun 20.
Isomaltulose synthase (PalI) of Klebsiella sp . LX3 . Crystal structure and implication of mechanism; Zhang D et al.; Isomaltulose synthase from Klebsiella sp . LX3 (PalI, EC 5.4.99.11) catalyzes the isomerization of sucrose to produce isomaltulose (alpha-D-glucosylpyranosyl-1,6-D-fructofuranose) and trehalulose (alpha-D-glucosylpyranosyl-1,1-d-fructofuranose) . The PalI structure, solved at 2.2-A resolution with an R-factor of 19.4% and Rfree of 24.2%, consists of three domains: an N-terminal catalytic (beta/alpha)8 domain, a subdomain between N beta 3 and N alpha 3, and a C-terminal domain having seven beta-strands . The active site architecture of PalI is identical to that of other glycoside hydrolase family 13 members, suggesting a similar mechanism in substrate binding and hydrolysis . However, a unique RLDRD motif in the proximity of the active site has been identified and shown biochemically to be responsible for sucrose isomerization . A two-step reaction mechanism for hydrolysis and isomerization, which occurs in the same pocket is proposed based on both the structural and biochemical data . Selected C-terminal truncations have been shown to reduce and even abolish the enzyme activity, consistent with the predicted role of the C-terminal residues in the maintenance of enzyme conformation and active site topology.

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