Surg Today, 1999, 29(9), 963 - 5 Biliary complications after orthotopic liver transplantation in rats; Nosaka T et al.; We recently experienced a high frequency of biliary complications after orthotopic liver transplantation in rats (22 of 25 cases (88%): biloma, 20 cases; biliary peritonitis, 2 cases) . These complications seemed to be rare in general, but some researchers reported such cases and addressed them mainly through rearterialization . The biliary complications we encountered were found to be associated with necrosis of the donor bile duct and an opportunistic infection of Enterobacteriaceae . After administering appropriate antibiotics, the complications significantly diminished (2 of 25 cases (8%), P = 0.0001) . The nonarterialized bile duct, which becomes ischemic soon after liver transplantation, appears to be susceptible to infections . Such opportunistic infections may prevent the development of arterial collaterals, causing bile duct necrosis and the subsequent leakage of bile juice . When biliary complications frequently occur after nonarterialized liver transplantation in rats, the possibility of an opportunistic infection should thus be considered. S Afr Med J, 1999 Aug, 89(8), 874 - 6 Antibiotic use and infection in snakebite victims; Blaylock RS; OBJECTIVES: To determine the incidence of infection in snakebite patients, the bacterial species involved, and the indication for antibiotics . METHOD: A prospective trial was undertaken at Eshowe Hospital, KwaZulu-Natal, involving 363 snakebite patients (records available for 310 patients) . It was protocol not to give antibiotics unless necrosis was present or anticipated . Bacterial species were identified from necrotic areas and abscesses . A swelling classification was devised . RESULTS: The syndromic presentation included no clinical envenomation (12%), painful swelling (85%), weakness (1.8%), venom ophthalmia (0.6%) and other presentations (0.6%) . There was 1 death, of an 11-year-old with gross swelling and thrombocytopenia . 15.2% of patients received antibiotics . Protocol was broken in 23 patients . None of the patients who did not receive an antibiotic became infected, and hospital stay was not prolonged in this group . Of 20 bacteria isolated, 18 were Gram-negative aerobic enterobacteriaceae . No anaerobes were cultured . CONCLUSIONS: Antibiotics should be reserved for those snakebite patients with necrosis (< 10%) and should cover Gram-negative aerobic bacilli and Gram-positive aerobic cocci. J Med Microbiol, 1999 Sep, 48(9), 841 - 7 Phylogenetic analysis of Calymmatobacterium granulomatis based on 16S rRNA gene sequences; Kharsany AB et al.; Calymmatobacterium granulomatis is the aetiological agent of granuloma inguinale - a chronic granulomatous genital infection - and is morphologically similar to members of the genus Klebsiella . This study determined the 16S rRNA gene sequence of C . granulomatis and the taxonomic position of the organism in relation to the genus Klebsiella . Genomic DNA was extracted from C . granulomatis-infected monocytes and from frozen and formalin-fixed paraffin wax-embedded tissue biopsy specimens from patients with histologically proven granuloma inguinale . The 16S rDNA was amplified by PCR with broad range oligonucleotide primers . The amplified DNA fragments were cloned into pMOS vector, digested with Bam HI and Pst1 restriction endonucleases, hybridised with a gram-negative bacterial probe (DL04), sequenced in both directions by the automated ALF DNA sequencer, verified on an ABI Prism 377 automated sequencer and analysed with DNASIS and MEGA software packages . Sequence analysis revealed DNA homology of 99% in C . granulomatis from the different sources, supporting the belief that the bacteria in the culture and the biopsy specimens belonged to the same species, although there was some diversity within the species . Phylogenetically, the strains were closely related to the genera Klebsiella and Enterobacter with similarities of 95% and 94% respectively . C . granulomatis is a unique species, distinct from other related organisms belonging to the gamma subclass of Proteobacteria. Scand J Infect Dis, 1999, 31(3), 287 - 91 Enterobacteriaceae meningitis in adults: a review of 20 consecutive cases 1977-97; Harder E et al.; Enterobacteriaceae are not a frequent cause of meningitis in adults and are seen mainly in neurosurgical patients and on occasion in elderly and debilitated patients . Consequently, most series studied have been small and selected . In order to obtain a clearer clinical picture, we reviewed 20 consecutive cases of Enterobacteriaceae meningitis admitted to the Department of Infectious Diseases, Rigshospitalet, Copenhagen, during the years 1977-97 . They comprised 1.5% of all cases of acute bacterial meningitis admitted to the department . All of the patients were either elderly and/or had 1 or more underlying diseases and predisposing factors . The clinical presentation and cerebrospinal fluid findings were not different from that of acute bacterial meningitis in general . The mortality rate was 40% and correlated with simultaneous bacteraemia . Complications were seen in a further 30% of patients and 25% survived with different sequelae . These high rates may, at least in part, be due to the advanced age and debilitated state of the patients studied . Escherichia coli was the most frequent of the Enterobacteriaceae. Biosci Biotechnol Biochem, 1999 Jul, 63(7), 1261 - 8 Purification, characterization and gene analysis of N-acetylglucosaminidase from Enterobacter sp . G-1; Matsuo Y et al.; Enterobacter sp . G-1 is a bacterium isolated previously as a chitinase-producing bacterium . We found this bacterium also produced N-acetylglucosaminidase and characterized that in this study . Extracellular N-acetylglucosaminidase of 92.0 kDa was purified near homogeneity by 8.57-fold from Enterobacter sp . G-1 . The optimum temperature and the optimum pH of the purified N-acetylglucosaminidase was 45 degrees C and 6.0, respectively . The N-terminal amino acid sequence of 23 residues of N-acetylglucosaminidase was identified . Based on the N-terminal sequence, we amplified pieces of the DNA fragments by PCR . Using these PCR products as probes, we screened the genomic library and successfully isolated the entire N-acetylglucosaminidase gene (designated nag1) from Enterobacter sp . G-1 . The nucleotide sequence of the nag1 gene was found to consist of 2,655 bp encoding a protein of 885 amino acid residues . Comparison of the deduced amino acid sequence from the nag1 gene found 97.3% identity with chitobiase from Serratia marcescens, 54.4% identity with N,N'-diacetylchitobiase from Vibrio harveyi, and 42.7% identity with N-acetylglucosaminidase (ExoI) from Vibrio furnissii . Enzymatic activity assay of N-acetylglucosaminidase indicated stronger activity toward PNP-GlcNAc than PNP-(GlcNAc)2 or PNP-(GlcNAc)3. FEMS Microbiol Lett, 1999 Aug 15, 177(2), 305 - 11 Glycosylation of the Enterobacter cloacae outer membrane protein OmpX in eukaryotic cells; de Kort G et al.; The topological model of the Enterobacter cloacae outer membrane protein OmpX showed three putative glycosylation sites . When OmpX was expressed in bacteria that were cultured under aerated conditions, no glycosylation was observed . The coupling of carbohydrate chains to the ompX gene product was also investigated in the eukaryotic baculovirus expression system . For this purpose, a recombinant ompX gene-containing baculovirus was made . Infection of insect cells with this recombinant virus resulted in the production of sufficient amounts of OmpX to study glycosylation . In this system, all potential N-glycosylation sites of OmpX were utilized . Furthermore, it became clear that glycosylated OmpX was retained in the insect cells and was not secreted in the medium . Given the fact that OmpX plays a role in the invasion of E . cloacae in rabbit enterocytes, glycosylation of this protein occurring only under specific conditions may be involved in this process. Acta Haematol, 1999, 102(1), 7 - 11 Bacteremia by gram-negative bacilli in patients with hematologic malignancies . Comparison of the clinical presentation and outcome of infections by enterobacteria and non-glucose-fermenting gram-negative bacilli; Martino R et al.; To compare the characteristics of bacteremic infections by different aerobic gram-negative bacilli (GNB) in patients with hematologic malignancies, we studied 54 consecutive monomicrobial bacteremias by Enterobacteriaceae (EB), 15 by Pseudomonas aeruginosa, 43 by other non-glucose-fermenting GNB (NGFGNB) and 11 by other GNB . Patients with EB and P . aeruginosa bacteremia usually developed the infection after intensive chemotherapy for leukemia or during a hematopoietic stem cell transplantation, while most infections in outpatients off therapy were due to NGFGNB . A significant proportion of bacteremias by EB (37%) and P . aeruginosa (40%) were accompanied by severe morbidity (septic shock, pneumonia or deep-seated organ infections) vs . only 7% of other NGFGNB (p < 0.01) . Most infections by these latter bacteria were catheter-related bacteremias (80 vs . 2% of EB, p < 0.005), while most EB infections (61%) were uncomplicated bacteremias of unknown source (vs . 14% of other NGFGNB, p < 0.005) . Appropriate antibiotics alone cured 98% of EB and 73% of P . aeruginosa bacteremias but only 26% of other NGFGNB (p < 0.005 for both differences), which were cured by catheter removal in 70%, usually after failure of antibiotic treatment . In conclusion, our results suggest that there are significant differences in the patient populations and clinical characteristics of bacteremic infections by the classic GNB (EB and P . aeruginosa) and the new NGFGNB in adults with hematologic malignancies. Clin Exp Immunol, 1999 Sep, 117(3), 568 - 73 Anti-lactoferrin antibodies and other types of anti-neutrophil cytoplasmic antibodies (ANCA) in reactive arthritis and ankylosing spondylitis; Locht H et al.; Fifty-five serum samples from patients with reactive arthritis (ReA), 40 from patients with ankylosing spondylitis (AS) and three from patients with chronic sacroiliac joint arthritis were analysed for the presence of ANCA of IgG class by means of enzyme immunosorbent assay using lactoferrin (Lf), myeloperoxidase (MPO) and antigen extracted from azurophil granules ('alpha-antigen') containing proteinase 3 (PR3) as substrate . IgG-ANCA were found in 31 (56%) patients with ReA . Twenty-three (42%) had anti-Lf antibodies, nine (16%) had anti-MPO and eight (15%) had anti-alpha-antigen antibodies, none of which reacted with PR3 . Only six (14%) AS or sacroiliac joint arthritis patients had ANCA (P < 0.001) . Three (7%) had anti-Lf, two (5%) anti-MPO and two (5%) anti-alpha-antigen antibodies . Yersinia and Salmonella bacteria were separated by SDS-PAGE and blots were incubated with serum from rabbits immunized with human Lf . The hyperimmune serum recognized a band of 78 kD from both bacteria which was not seen when preimmune serum was used . The reaction to the 78-kD antigen could be completely inhibited when anti-Lf antibodies were absorbed on Lf coupled to cyanogen bromide-activated Sepharose, possibly indicating cross-reacting epitopes in Lf and enterobacterial antigen. Braz J Med Biol Res, 1999 Sep, 32(9), 1077 - 81 Phenotyping and genotyping methods applied to investigate the relatedness of Brazilian isolates of Enterobacter cloacae; Darini AL et al.; In order to evaluate the resolving power of several typing methods to identify relatedness among Brazilian strains of Enterobacter cloacae, we selected twenty isolates from different patients on three wards of a University Hospital (Orthopedics, Nephrology, and Hematology) . Traditional phenotyping methods applied to isolates included biotyping, antibiotic sensitivity, phage-typing, and O-serotyping . Plasmid profile analysis, ribotyping, and macrorestriction analysis by pulsed-field gel electrophoresis (PFGE) were used as genotyping methods . Sero- and phage-typing were not useful since the majority of isolates could not be subtyped by these methods . Biotyping, antibiogram and plasmid profile permitted us to classify the samples into different groups depending on the method used, and consequently were not reliable . Ribotyping and PFGE were significantly correlated with the clinical epidemiological analysis . PFGE did not type strains containing nonspecific DNase . Ribotyping was the most discriminative method for typing Brazilian isolates of E . cloacae. J Biol Chem, 1999 Sep 3, 274(36), 25260 - 5 Inhibition of the broad spectrum nonmetallocarbapenamase of class A (NMC-A) beta-lactamase from Enterobacter cloacae by monocyclic beta-lactams; Mourey L et al.; beta-Lactamases hydrolyze beta-lactam antibiotics, a reaction that destroys their antibacterial activity . These enzymes, of which four classes are known, are the primary cause of resistance to beta-lactam antibiotics . The class A beta-lactamases form the largest group . A novel class A beta-lactamase, named the nonmetallocarbapenamase of class A (NMC-A) beta-lactamase, has been discovered recently that has a broad substrate profile that included carbapenem antibiotics . This is a serious development, since carbapenems have been relatively immune to the action of these resistance enzymes . Inhibitors for this enzyme are sought . We describe herein that a type of monobactam molecule of our design inactivates the NMC-A beta-lactamase rapidly, efficiently, and irreversibly . The mechanism of inactivation was investigated by solving the x-ray structure of the inhibited NMC-A enzyme to 1.95 A resolution . The structure shed light on the nature of the fragmentation of the inhibitor on enzyme acylation and indicated that there are two acyl-enzyme species that account for enzyme inhibition . Each of these inhibited enzyme species is trapped in a distinct local energy minimum that does not predispose the inhibitor species for deacylation, accounting for the irreversible mode of enzyme inhibition . Molecular dynamics simulations provided evidence in favor of a dynamic motion for the acyl-enzyme species, which samples a considerable conformational space prior to the entrapment of the two stable acyl-enzyme species in the local energy minima . A discussion of the likelihood of such dynamic motion for turnover of substrates during the normal catalytic processes of the enzyme is presented. J Hosp Infect, 1999 Sep, 43(1), 49 - 56 An analysis of hospital-acquired bacteraemia in intensive care unit patients in a university hospital in Kuwait; Jamal WY et al.; An analysis of hospital-acquired bacteraemia among ICU patients was carried out over a two-year period in order to determine the incidence, associated mortality rate and susceptibility pattern of causative pathogens . There was a high incidence of bacteraemia, occurring in 127 (18.4%) of 692 patients . Mortality attributable to nosocomial bacteraemia was 52% of the total 79 deaths from all causes . The highest mortality rate (58.5%) occurred in patients with fungal infections, whilst death from Gram-negative bacteraemia was only 17% . Over 98% of patients had underlying disease . Nearly half (46.8%) of 267 organisms isolated were Gram-positive . In comparison, Gram-negative bacteria accounted for 36.6% and the rest (17.6%) were fungi (mainly Candida albicans) . The majority of the bactereamic episodes were monomicrobial (90.2%) . Coagulase-negative staphylococci (CNS) were the commonest pathogens isolated, representing 32.6% of all organisms . Inducible beta-lactamase producing organism (Enterobacter spp . 9.7%, Serratia marcescens 6.7%, Klebsiella pneumoniae 6% and Pseudomonas aeruginosa 6%) formed the bulk of Gram-negative bacteria . In contrast, Escherichia coli (7.5%) and K . pneumoniae (4%) were the commonest Gram-negative bacteria from hospital-acquired bacteraemia in the general hospital population . The majority (80%) of CNS were resistant to methicillin (MRSE) but susceptible to vancomycin; they were relatively resistant to erythromycin, clindamycin and beta-lactams antibiotics . Whilst Gram-negative organisms were relatively susceptible to imipenem (85%), ciprofloxacin (88%) and amikacin (87%), they had unacceptably low levels of susceptibility to cefuroxime (59.3%), cefotaxime (71%), ceftazidime (60.9%), and piperacillin (51.1%) . This study shows that hospital-acquired bacteraemia in ICU patients carries a poor prognosis . Information regarding the infective agents and their susceptibility in the ICU setting is valuable for the selection of empirical therapy before culture and susceptibility results are known . Transgenic Res, 1998 May, 7(3), 157 - 63 Biosafety of E . coli beta-glucuronidase (GUS) in plants; Gilissen LJ et al.; The beta-glucuronidase (GUS) gene is to date the most frequently used reporter gene in plants . Marketing of crops containing this gene requires prior evaluation of their biosafety . To aid such evaluations of the GUS gene, irrespective of the plant into which the gene has been introduced, the ecological and toxicological aspects of the gene and gene product have been examined . GUS activity is found in many bacterial species, is common in all tissues of vertebrates and is also present in organisms of various invertebrate taxa . The transgenic GUS originates from the enterobacterial species Escherichia coli that is widespread in the vertebrate intestine, and in soil and water ecosystems . Any GUS activity added to the ecosystem through genetically modified plants will be of no or minor influence . Selective advantages to genetically modified plants that posses and express the E . coli GUS transgene are unlikely . No increase of weediness of E . coli GUS expressing crop plants, or wild relatives that might have received the transgene through outcrossing, is expected . Since E . coli GUS naturally occurs ubiquitously in the digestive tract of consumers, its presence in food and feed from genetically modified plants is unlikely to cause any harm . E . coli GUS in genetically modified plants and their products can be regarded as safe for the environment and consumers. J Antimicrob Chemother, 1999 Jul, 44(1), 113 - 6 Antimicrobial resistance patterns in urinary isolates from nursing home residents . Fifteen years of data reviewed; Vromen M et al.; The antibiotic resistance patterns of gram-negative bacteria isolated from nursing home patients between 1983 and 1997 were analysed . Escherichia coli was the most prevalent isolate (48%) followed by Proteus spp . (26%) and other Enterobacteriaceae (20%) . During the study period, the susceptibility of E . coli decreased for co-trimoxazole (79% to 62%), increased for nitrofurantoin (79% to 91%) and remained unchanged for amoxycillin (41%) . Susceptibility to norfloxacin, available from 1990, decreased from 87% to 71% . Similar trends were observed when the susceptibilities of all gram-negative urinary pathogens were combined . The changes in susceptibility can probably be attributed to the empirical prescribing practices in the nursing homes studied. J Food Prot, 1999 Aug, 62(8), 913 - 20 Microbial shelf life determination of vacuum-packaged fresh beef treated with polylactic acid, lactic acid, and nisin solutions; Ariyapitipun T et al.; The effectiveness of polylactic acid, lactic acid, nisin, and combinations of the acids and nisin on extending the shelf-life of raw beef was determined . Fresh beef pieces (5 by 5 by 2.5 cm) were dipped in a solution of 2% low molecular weight polylactic acid (LMW-PLA), 2% lactic acid (LA), 200 IU of nisin per ml, or the combinations of nisin in either 2% LMW-PLA or 2% LA . The samples were then drip-dried, vacuum-packaged, and stored at 4 degrees C for up to 56 days . The beef surface pH values and numbers of psychrotrophic aerobic bacteria, psychrotrophic and mesophilic Enterobacteriaceae, Pseudomonas, and Lactobacillus were determined weekly for 56 days . The average surface pH values of the beef samples treated with 2% LMW-PLA or the combination of 200 IU of nisin per ml and 2% LMW-PLA were significantly reduced to 5.19 and 5.17, respectively, at day 0 (P < or = 0.05), while those decontaminated with 2% LA or 200 IU of nisin per ml in 2% LA solution were significantly decreased from 5.62 to 4.98 and 4.96, respectively . The 2% LMW-PLA, 2% LA, or the combinations of each acid and nisin showed immediate inhibitory effects on psychrotrophic aerobic bacteria (1.94, 2.36, 2.59, and 1.76 log reduction, respectively), psychrotrophic Enterobacteriaceae (1.37, 1.86, 1.77, and 1.35 log reduction, respectively), mesophilic Enterobacteriaceae (1.00, 1.00, 0.82, and 0.68 log reduction, respectively), and Pseudomonas (1.77, 1.57, 1.76, and 1.41 log reduction, respectively) on fresh beef (P < or = 0.05) . The reduction was evident up to 56 days as seen by the numbers of Enterobacteriaceae and Pseudomonas (P < or = 0.05) . Because there was no interaction between treatments and storage times, the data in each period were combined and presented as effect of treatments on overall microbial counts of fresh beef . It was found that 2% LMW-PLA, 2% LA, and the combinations of each acid and nisin significantly lowered the population of the above organisms compared with the untreated control, water, or nisin alone (P < or = 0.05). Pharmacotherapy, 1999 Aug, 19(8 Pt 2), 120S - 128S; discussion 133S-137S Successful interventions for gram-negative resistance to extended-spectrum beta-lactam antiobiotics; Rice LB; Antibiotic resistance among nosocomial pathogens in this country's hospitals adds significantly to patient morbidity and mortality, and the cost of health care . Optimism for identifying antimicrobial agents that would "solve the problem" of resistance has been replaced by a much more guarded and realistic view of the battle between humans and pathogenic microorganisms . Efforts now are more appropriately directed toward limiting, rather than completely eliminating, resistance, generally by either infection control or antibiotic control measures, and sometime combinations of the two . Methicillin-oxacillin resistance in Staphylococcus aureus (MRSA) results from the expression of an acquired penicillin-binding protein (PBP 2a) that is not transferable in vitro . In most hospitals, even those with high percentages of MRSA, relatively few resistant clones are identified, suggesting transmission of individual strains throughout the hospital population . Because person-to-person spread is so important in transmission of MRSA, strategies aimed at preventing transmission of the resistant strains are remarkably effective when strictly enforced . Ceftazidime resistance in Enterobacteriaceae results from point mutations within genes that encode widely prevalent and often transferable plasmid-mediated enzymes . In addition, mutations of these genes that allow hydrolysis of cephalosporins usually result in decreased activity against other drugs, including the penicillins and beta-lactamase inhibitors . Effective measures to control ceftazidime-resistant Enterobacteriaceae have as their cornerstone limiting administration of antibiotics that select for the emergence and spread of these mutations, especially ceftazidime . The importance of infection-control techniques in limiting the prevalence of ceftazidime-resistant Enterobacteriaceae is less well established . Methods that are informed by a detailed understanding of the molecular mechanisms of resistance and resistance spread offer the best hope for limiting dissemination of antibiotic-resistant bacteria in a cost-effective manner. J Clin Microbiol, 1999 Sep, 37(9), 3029 - 30 Rapid detection of methicillin resistance in Staphylococcus aureus isolates by the MRSA-screen latex agglutination test; van Leeuwen WB et al.; The slide agglutination test MRSA-Screen (Denka Seiken Co., Niigata, Japan) was compared with the mecA PCR ("gold standard") for the detection of methicillin resistance in Staphylococcus aureus . The MRSA-Screen test detected the penicillin-binding protein 2a (PBP2a) antigen in 87 of 90 genetically diverse methicillin-resistant S . aureus (MRSA) stock culture strains, leading to a sensitivity of 97% . The three discrepant MRSA strains displayed positive results only after induction of the mecA gene by exposure to methicillin . Both mecA PCR and MRSA-Screen displayed negative results among the methicillin-susceptible S . aureus strains (n = 106), as well as for Micrococcus spp . (n = 10), members of the family Enterobacteriaceae (n = 10), Streptococcus pneumoniae (n = 10), and Enterococcus spp . (n = 10) (specificity = 100%) . Producing the same PBP2a antigen, all 10 methicillin-resistant Staphylococcus epidermidis strains score positived in both the latex test and the mecA PCR . Consequently, the MRSA-Screen test should be applied only after identification of the MRSA strain to the species level to rule out coagulase-negative staphylococci . In conclusion, due to excellent specificity and sensitivity the MRSA-Screen latex test has the potential to be successfully used for routine applications in the microbiology laboratory. J Clin Microbiol, 1999 Sep, 37(9), 2772 - 6 PCR-Based methods for genotyping viridans group streptococci; Alam S et al.; Standard repetitive extragenic palindromic (REP)-PCR, enterobacterial repetitive intergenic consensus-PCR, and Salmonella enteritidis repetitive element-PCR methods for bacterial strain typing were performed with DNA extracted by boiling members of each of the currently recognized species of human viridans group streptococci . Each of the methods was reproducible . The unique isolates (n = 72) from 15 species of viridans group streptococci were readily distinguishable, with no two isolates showing greater than 90% per cent similarity . The majority of strains exhibited much less than 90% similarity . Isolates identical by REP-PCR were also identical by the other two methods . These PCR-based typing methods, although they do not permit determination of the species of the isolates, are simple to perform and are suitable for clinical and ecological investigations of viridans group streptococci. Immunology, 1999 Jul, 97(3), 420 - 8 Enterobacterial infection modulates major histocompatibility complex class I expression on mononuclear cells; Kirveskari J et al.; Major histocompatibility complex (MHC) class I expression is reduced in several viral infections, but it is not known whether the same happens during infections caused by intracellular enterobacteria . In this study, the expression of MHC class I antigens on peripheral blood mononuclear cells (PBMC) from 16 patients with Salmonella, Yersinia, or Klebsiella infection was investigated . During or after the acute infection, the expression of MHC class I antigens was markedly decreased in eight patients, all with genotype HLA-B27, and six out of eight with reactive arthritis (ReA) . A significant decrease of monomorphic MHC class I was found in three patients, of HLA-B27 in eight (P<0.05) and of HLA-A2 in two . However, patients negative for the HLA-B27 genotype, or healthy HLA-B27-positive individuals, did not have a significant decrease of MHC class I antigens . During the decreased expression on the cell surface, intracellular retention of MHC class I antigens was observed, whereas HLA-B27 mRNA levels did not vary significantly . This is the first evidence that enterobacterial infection may down-regulate expression of MHC class I molecules in vivo and that down-regulation is predominant in patients with the HLA-B27 genotype. Science, 1999 Aug 13, 285(5430), 1061 - 6 X-ray structure of the FimC-FimH chaperone-adhesin complex from uropathogenic Escherichia coli; Choudhury D et al.; Type 1 pili-adhesive fibers expressed in most members of the Enterobacteriaceae family-mediate binding to mannose receptors on host cells through the FimH adhesin . Pilus biogenesis proceeds by way of the chaperone/usher pathway . The x-ray structure of the FimC-FimH chaperone-adhesin complex from uropathogenic Escherichia coli at 2.5 angstrom resolution reveals the basis for carbohydrate recognition and for pilus assembly . The carboxyl-terminal pilin domain of FimH has an immunoglobulin-like fold, except that the seventh strand is missing, leaving part of the hydrophobic core exposed . A donor strand complementation mechanism in which the chaperone donates a strand to complete the pilin domain explains the basis for both chaperone function and pilus biogenesis. FEMS Immunol Med Microbiol, 1999 Aug 1, 25(1-2), 115 - 23 Animal models used to test the interactions between infectious agents and products of cigarette smoked implicated in sudden infant death syndrome; Sayers NM et al.; Animal test systems are reviewed that have relevance to sudden infant death syndrome (SIDS) are reviewed . These test interactions between infectious agents (or their toxins) and products of cigarette smoke . Infectious agents implicated in SIDS include members of the enterobacteria and clostridia, Staphylococcus aureus and Streptococcus pyogenes . Smoking is thought to be the single most preventable cause of SIDS . Tobacco smoke contains many extremely toxic products including cyanide and nicotine . Many animal test systems are available to examine the potency of bacterial toxins and smoke-derived components . These include mice, hamsters, rats and chick embryos . Such systems reveal synergy between bacterial toxins, especially endotoxin and superantigens . They have also demonstrated potentiation of low levels of bacterial toxin by low levels of both nicotine and its primary metabolite, cotinine . These findings suggest a possible causal explanation for the fact that passive exposure to cigarette smoke is a risk factor in sudden infant death syndrome. FEMS Immunol Med Microbiol, 1999 Aug 1, 25(1-2), 37 - 50 Immunological evidence for a bacterial toxin aetiology in sudden infant death syndrome; Siarakas S et al.; Toxin-specific antibodies to clostridial, enterobacterial and staphylococcal toxins implicated in sudden infant death syndrome were studied in sera from sudden infant death syndrome infants and a comparison group of infants (babies with phenylketonuria) . The results indicated a higher proportion of sera from sudden infant death syndrome infants contained IgA that bound to clostridial and enterobacterial toxins but a higher proportion of sera from the phenylketonuria comparison group contained IgA that bound staphylococcal toxins . The higher proportion of serum samples with IgG and IgM in the healthy comparison babies serum probably indicated immunity in this group of babies to these toxins . The effect of gender and age had a minimal effect on the incidence of these antibodies . The presence of toxin-specific antibodies in sudden infant death syndrome and the of comparison infants suggests that all infants are exposed to these toxins and most babies successfully overcome the toxic challenge . Some infants with predisposing risk factors (temperature change, smoking, infection, immune development, sleeping position, etc.) that could affect the baby's immune competency could succumb to these and possibly other toxins . This immunological evidence further strengthens the view that bacterial toxins are a significant cause of sudden infant death syndrome. Ophthalmology, 1999 Aug, 106(8), 1500 - 3 Microbiologic analysis of bottled water: is it safe for use with contact lenses? Penland RL, Wilhelmus KR. OBJECTIVE: To analyze commercially available bottled water as a possible source of microbial contamination of contact lenses . METHODS: Two different lots of 23 brands of noncarbonated bottled water were tested for coliforms, total bacteria, fungi, and free-living amebae . A sample consisted of three separate 100-ml aliquots from one lot of each brand (46 samples) . Aliquots were vacuum-filtered using a 0.45-microm Nalgene analytical filter unit, and the membrane filter was placed on a filter pad in a Petri dish containing test medium . Plates were examined under a stereomicroscope, and the number of colony-forming units (CFUs) was calculated for each sample . To test for the presence of free-living amebae, three aliquots totaling approximately 3800 ml were concentrated using 8-microm filters, and the filters were placed on non-nutrient agar with live Enterobacter aerogenes . To assess the possibility of contaminating contact lenses, etafilcon lenses were rinsed in 2-ml aliquots of four brands of bottled water and then cultured . RESULTS: Seventeen (37%) of 46 samples, representing 11 (48%) of 23 brands, contained viable micro-organisms . Bacteria, including coliforms, were recovered from 12 samples of 8 brands . Yeasts or molds were recovered from seven samples of five brands . Free-living amebae were isolated from two samples, and fresh-water algae were found in both samples of one brand . Nine (20%) of 46 samples, representing 7 (30%) of the 23 brands, had more than 500 CFUs per ml or contained coliforms . Sterile contact lenses became contaminated when exposed for 1 minute to two of four brands of water from which micro-organisms were recovered . CONCLUSION: Some bottled waters contain high numbers of potential ocular pathogens . Bottled water is not safe for routine use with contact lenses. Eur J Clin Microbiol Infect Dis, 1999 Jun, 18(6), 414 - 21 Prevalence of aminoglycoside resistance in 20 European university hospitals participating in the European SENTRY Antimicrobial Surveillance Programme; Schmitz FJ et al.; The aim of this study was to analyse the current prevalence of aminoglycoside resistance in Europe and compare the in vitro activity of amikacin, gentamicin, and tobramycin against 7057 bacterial isolates from 20 university hospitals participating in the European SENTRY Antimicrobial Surveillance Programme . Amikacin exhibited better in vitro activity than tobramycin and gentamicin against most gram-negative bacilli in Europe . The resistance levels were 0.4-3% for amikacin, 2-13.1% for gentamicin, and 2.5-15.3% for tobramycin among different members of the family Enterobacteriaceae . Of the Staphylococcus aureus isolates tested, 75% were susceptible to gentamicin . Only 21% of all enterococcal strains tested were fully susceptible to gentamicin . Although intra-country variations in the prevalence of resistance phenotypes in Escherichia coli, Klebsiella spp., and Pseudomonas aeruginosa as well as in staphylococci and enterococci did occur, aminoglycoside resistance rates were generally higher in Italy, Portugal, Spain, Greece, France, the UK, and Poland than in Austria, Belgium, Germany, the Netherlands, and Switzerland . Compared with the 1987-88 data of the European Study Group on Antibiotic Resistance, gentamicin resistance has increased up to 5% in some gram-negative bacterial species . Furthermore, a greater than 10% increase in resistance to gentamicin has been seen in Staphylococcus aureus during the last decade . The reason for this observation is unclear, although changes in antibiotic prescribing patterns that result in increased selective pressure from gentamicin may have contributed to these increased rates of aminoglycoside resistance. Eur J Clin Microbiol Infect Dis, 1999 Jun, 18(6), 403 - 8 Frequency of occurrence and antimicrobial susceptibility of bacterial pathogens associated with skin and soft tissue infections during 1997 from an International Surveillance Programme . SENTRY Participants Group; Jones ME et al.; The SENTRY Antimicrobial Surveillance Programme was established to provide a coordinated, standardised, international surveillance on antimicrobial resistance . In one part of the programme, isolates from skin and soft tissue infections sent from 20 hospitals in 12 different European countries were investigated in the European coordinating centre . Of 1013 isolates, Staphylococcus aureus and Pseudomonas aeruginosa were the most significant species, constituting almost 50% of the referred isolates . Methicillin resistance in Staphylococcus aureus averaged 22% across Europe, only slightly less than that in isolates derived from blood . Less than 5% of the enterococcal isolates were resistant to vancomycin . Piperacillin/tazobactam was the most active penicillin-derived beta-lactam compound against Pseudomonas aeruginosa, inhibiting 91.3% of the isolates, while ceftazidime and cefepime were the most active cephalosporins, inhibiting 85.8% and 80.3% of the isolates, respectively . Putative extended-spectrum beta-lactamase production was not detected in Escherichia coli and was found in only 5.1% of the Klebsiella pneumoniae isolates . In general, strains of the family Enterobacteriaceae remained mostly susceptible to carbapenems, cefepime, and amikacin. Biochemistry, 1999 Aug 10, 38(32), 10499 - 510 On the importance of a methyl group in beta-lactamase evolution: free energy profiles and molecular modeling; Bernstein NJ et al.; beta-Lactam antibiotics are generally thought to inhibit their target enzymes, the bacterial cell wall-synthesizing DD-peptidases, because of their resemblance to D-alanyl-D-alanine peptides . Although a favorable conformation of the latter does structurally resemble the beta-lactams with respect to backbone conformation, a significant difference is the presence of a D-methyl substituent on the penultimate alanine residue of the cell wall peptide . A classical beta-lactam antibiotic has a hydrogen in the corresponding position . In the process of evolution of a beta-lactamase from a DD-peptidase, it seems likely that this D-methyl group would be selected against, to ensure that the former enzyme would hydrolyze beta-lactams rather than peptides . In this paper, the effect of the penultimate D-alanine residue (as opposed to a glycine residue) has been examined in peptide substrates of a present-day DD-peptidase and a beta-lactamase . The peptides N-(phenylacetyl)-D-alanyl-D-phenylalanine and N-(phenylacetyl)glycyl-D-phenylalanine were used as a test pair against the DD-peptidase of Streptomyces R61 and the structurally very similar class C beta-lactamase of Enterobacter cloacae P99 . The kinetics of turnover of both of these substrates were determined for both enzymes . To quantify the partitioning of the acyl-enzyme intermediate, the aminolysis by D-phenylalanine of a cognate pair of depsipeptides was also studied . Thus, free energy-reaction coordinate diagrams were constructed for turnover of both peptides by both enzymes . Comparison of these profiles showed that the D-methyl group is preferred over hydrogen by the DD-peptidase at all stages of catalysis (acyl-enzyme and acylation and deacylation transition states), whereas the beta-lactamase selects against the D-methyl group only at the peptide acylation transition state . A process of evolution by uniform dissociation of the methyl group by the beta-lactamase has apparently occurred . These results were explored structurally by computational models of the acylation tetrahedral intermediates . A methyl group pocket on the DD-peptidase, less favorable on the beta-lactamase, was identified . The interaction of the leaving group, the terminal D-alanine residue, with the two enzymes was interesting, since it seemed that different positively charged active site residues were directly associated with the carboxylate, Lys 315 in the beta-lactamase and Arg 285 (rather than His 298) in the case of the DD-peptidase . The problems posed by larger substituents on the penultimate residue of the peptide, and in particular by the heterocyclic substituent present in a bicyclic beta-lactam, were analyzed . Qualitative and quantitative analysis of the models support the proposed importance of the penultimate D-alanine in beta-lactamase evolution. Biochemistry, 1999 Aug 10, 38(32), 10256 - 61 Structure of the extended-spectrum class C beta-lactamase of Enterobacter cloacae GC1, a natural mutant with a tandem tripeptide insertion; Crichlow GV et al.; A class C beta-lactamase from a clinical isolate of Enterobacter cloacae strain GC1 with improved hydrolytic activity for oxyimino beta-lactam antibiotics has been analyzed by X-ray crystallography to 1.8 A resolution . Relative to the wild-type P99 beta-lactamase, this natural mutant contains a highly unique tandem repeat Ala211-Val212-Arg213 {Nugaka et al . (1995) J . Biol . Chem . 270, 5729-5735} . The 39.4 kDa chromosomal beta-lactamase crystallizes from poly(ethylene glycol) 8000 in potassium phosphate in space group P2(1)2(1)2 with cell dimensions a = 78.0 A, b = 69.5 A, and c = 63.1 A . The crystal structure was solved by the molecular replacement method, and the model has been refined to an R-factor of 0.20 for all nonzero data from 8 to 1.8 A . Deviations of model bonds and angles from ideal values are 0.008 A and 1.4 degrees, respectively . Overlay of alpha-carbon atoms in the GC1 and P99 beta-lactamases results in an rms deviation of 0.6 A . Largest deviations occur in a loop containing Gln120 and in the Omega loop region (200-218) where the three residues 213-215 are disordered . Possibly as a result of this disorder, the width of the opening to the substrate binding cavity, as measured from the 318-324 beta-strand to two loops containing Gln120 and Tyr150 on the other side, is 0.6-1.4 A wider than in P99 . It is suggested that conformational flexibility in the expanded Omega loop, and its influence on adjacent protein structure, may facilitate hydrolysis of oxyimino beta-lactams by making the acyl intermediate more open to attack by water . Nevertheless, backbone atoms in core catalytic site residues Ser64, Lys67, Tyr150, Asn152, Lys318, and Ser321 deviate only 0.4 A (rmsd) from atoms in P99 . A rotation of a potential catalytic base, Tyr150, relative to P99 at pH 8, is consistent with the requirement for a lower than normal pK(a) for this residue. APMIS, 1999 Jul, 107(7), 703 - 8 An evaluation of susceptibility testing methods for ampicillin-sulbactam using a panel of beta-lactamase-producing bacteria; Siu LK et al.; Bacteria possessing TEM-1-like beta-lactamases are generally regarded as susceptible to ampicillin-sulbactam (SAM), while those harboring OXA-1 enzymes are considered resistant . The current study was undertaken to compare susceptibility testing using various combinations of ampicillin and sulbactam to improve clinical correlation . Members of the Enterobacteriaceae family harboring TEM-1, SHV-1 or OXA-1-like beta-lactamases were tested using the agar dilution method . A substantial proportion of strains harboring OXA-1-like beta-lactamases showed false susceptibility to SAM at the 1:1 ratio or fixed sulbactam concentration of 8 microg/ml . At a fixed sulbactam concentration of 4 microg/ml, the activity of ampicillin-sulbactam appeared to be reduced, with large numbers of TEM-1 producers becoming frankly resistant . Results obtained with the 2:1 ratio exhibited the closest correlation with that obtained by the currently recommended disk diffusion test . However, very major errors were still found between the disk diffusion test and agar dilution test, suggesting the necessity for consideration of a change in criteria for interpretation of disk diffusion test results . In conclusion, SAM susceptibility testing by agar dilution using other than a 2:1 ratio is not recommended and results should be interpreted with caution. Zhonghua Nei Ke Za Zhi, 1997 Aug, 36(8), 540 - 2 {The antibacterial activity of cefmetazole and other antibiotics to 463 isolates}; Xu Y et al.; We compared the in-vitro antibacterial activity of cefmetazole and other 4 antibiotics against clinical isolates . The minimal inhibitory concentration (MIC) of cefmetazole against 463 isolates was determined by standard (NCCLS) agar dilution testing, and compared with that of cefazolin, cefuroxime, cefotaxime and ceftazidime . The results showed that cefmetazole was the most effective in 5 antibiotics to indole (+)P . vulgaris and M . morganii (MIC(90) 8 mg/L), and cefmetazole had the same activity as cefotaxime (sensitive 82%-100%), but less activity than ceftazidime (sensitive 88%-100%) against E . coli, K . pneumoniae and P . morabilis . To oxacillin-sensitive staphylococci, cefmetazole was highly active, with the MIC 90 of 4 mg/L . Our results indicate that cefmetazole is highly active against Enterobacteriaceae and oxacillin-sensitive staphylococci. Medicina (B Aires), 1999, 59 Suppl 1, 8 - 16 {In vitro activity of trovafloxacin, of other fluoroquinolones and of related antimicrobials against clinical isolates . Grupo colaborativo WHONET-Argentina}; Rossi A et al.; The in vitro activity of trovafloxacin (TRV) has been evaluated in comparison with that of other antimicrobial agents against 5671 clinical isolates recovered by representative institutions of different provinces in our country . The resistance percentage to gentamicin and third generation cephalosporins among enterobacteriaceae was high: 17% and 16% respectively, with a considerable variation according to the analyzed species . The resistance to ciprofloxacin (CIP) and TRV affected approximately 9% of the isolates, without significant differences between both drugs . Fluoroquinolones (FQ) presented excellent activity on 166 isolates of Salmonella spp., 208 of Shigella flexneri and 76 of Shigella sonnei, where only one S.sonnei isolate was resistant to CIP, but susceptible to TRV . About half the isolates of Salmonella spp . and S.sonnei and almost all S.flexneri isolates were resistant to ampicillin, and more than 60% of Shigella spp . isolates were resistant to trimethoprim-sulfamethoxazole . A 41% of Staphylococcus aureus and 55% of coagulase-negative staphylococci isolates were resistant to oxacillin, presenting a highly associated multi-resistance . The resistance to FQ was also strongly related to oxacillin resistance, but the resistance to TRV was significantly lower than the CIP resistance: 9% vs 57% for S.aureus and 4% vs 41% for coagulase-negative staphylococci . A similar behavior was observed with Enterococcus spp., where 54% of the isolates were resistant to norfloxacin and only 13% were resistant to TRV . Neither Streptococcus pneumoniae (n = 193) nor Haemophilus influenzae (n = 139) isolates presented resistant to TRV. Eur J Ophthalmol, 1999 Apr-Jun, 9(2), 120 - 4 Bacteriological profile of ophthalmic infections in an Israeli hospital; Mezer E et al.; AIM: To find the optimal antibiotic treatment for ophthalmic infections in an Israeli hospital . METHODS: In a retrospective study from our laboratory, which serves as both a primary and secondary referral center, we analyzed the bacteriological profile and the antibiotic sensitivity of ophthalmic infections using the computerized laboratory reports of 331 consecutive ophthlamic bacteriological cultures from patients with various ophthalmic infections . RESULTS: Microbiological growth was obtained in 113 samples (34.1%) . The most commonly isolated organism was coagulase-negative staphylococcus (19.5%), followed by coagulase-positive staphylococcus (16.8%), Enterobacteriaceae (14.2%), Pseudomonas aeruginosa (13.3%), and streptococcal species (8.9%) . Pseudomonas species were the most common isolates from the lacrimal pathways (20.0%) . Streptococci were the most common isolates cultured from the conjunctiva (27.3%) . Coagulase-positive staphylococcus was the most common isolate from corneal ulcers (33.3%), and coagulase-negative staphylococcus from the vitreous (30.8%) . The overall antibiotic sensitivity of common ophthalmic pathogens was similar to that reported from other parts of the world . CONCLUSIONS: Although essentially similar to previous series, this report from the Middle East differs as follows . Firstly, Pseudomonas species were the most common isolates from the lacrimal pathways . Secondly, the overall rate of streptococcal isolates was lower than in previous reports . Thirdly, streptococcal species were rarely isolated from corneal samples . Although other studies from the region have described the causative organisms of ocular infections in specific ocular sites, this is the first study from the Middle East to summarize the full bacteriological profile of ocular infections in one medical center. Lett Appl Microbiol, 1999 Jul, 29(1), 37 - 41 Colicin V can be produced by lactic acid bacteria; McCormick JK et al.; Colicin V is a small, proteinaceous bacterial toxin, produced by many strains of Escherichia coli and other members of the Enterobacteriaceae, that fits the definition of class II bacteriocins of Gram-positive bacteria . Export of colicin V is dependent on specific ABC (ATP-binding cassette) secretion proteins which recognize a double-glycine-type leader peptide on the immature colicin V bacteriocin . Replacement of the colicin V leader peptide by a signal peptide from the signal sequence-dependent bacteriocin divergicin A allowed expression of colicin V in lactic acid bacteria . This system may serve as a model for the heterologous expression of other small bacteriocins active against Gram-negative bacteria and other antibacterial peptides from lactic acid bacteria. J Appl Microbiol, 1999 Jul, 87(1), 131 - 40 Culture-independent quantification of physiologically-active microbial groups in fermented foods using rRNA-targeted oligonucleotide probes: application to pozol, a Mexican lactic acid fermented maize dough; Ampe F et al.; Nine phylogenetic oligonucleotide probes were used to describe at the genus level the microbial community responsible for the spontaneous fermentation of maize, leading to the production of Mexican pozol . Ribosomal RNAs of specific groups and genera, in particular, lactic acid bacteria, were quantified using a culture-independent approach . In the early stage of the fermentation, Lactococcus and Leuconostoc appeared to be the dominant genera . A contrario, these represented minor genera at the end of the fermentation when Lactobacillus dominated the process . In addition, eukaryotes seemed to play a significant role throughout the fermentation and enterobacteria could be detected by this method. J Chir (Paris), 1999 Mar, 136(1), 15 - 20 {Antibiotic treatment of peritonitis}; Chalfine A et al.; Secondary peritonitis usually results from perforation of a digestive tract organ . The bacterial contamination depends on the site of the perforation (supra or infra mesocolic) and the clinical setting (community or nosocomial) . Although bacteriological specimens have not been proven to be diagnostic in community-acquired peritonitis, they are nevertheless mandatory in the nosocomial setting due to the multiresistant nature of the pathogens . Experimental models have evidenced a biphasic course in peritonitis with microbial synergism between aerobic and anaerobic pathogens . These experimental studies have also evidenced the importance of treating enterobacteria and strict anaerobic pathogens . The treatment of community-acquired peritonitis should be targeted against Gram negative bacilli, strict anaerobic germs and enterococci . Resistant Gram negative bacilli and enterococci are the target bacteria for nosocomial peritonitis . Doses should be adapted to renal function and hemodynamic conditions using antibiotics with proven efficacy on susceptibility tests . The theoretical duration of treatment is a question of debate and should be adapted to each individual case. Antimicrob Agents Chemother, 1999 Aug, 43(8), 2069 - 73 TEM-24 produced by four different species of Enterobacteriaceae, including Providencia rettgeri, in a single patient; Marchandin H et al.; Four species of members of the family Enterobacteriaceae harboring extended-spectrum beta-lactamase (ESBL) were recovered in a single patient hospitalized in an intensive care unit . Among these isolates, we describe for the first time an ESBL-producing Providencia rettgeri strain . Bacteria from the same species were shown to be genetically related by pulsed-field gel electrophoresis analysis . These strains produced the same TEM derivative ESBL, characterized as TEM-24 . This enzyme had the peculiarity of being encoded by a large conjugative plasmid of 180 kb, never previously described for such an ESBL. Antimicrob Agents Chemother, 1999 Aug, 43(8), 2051 - 5 Comparative in vitro activities of ciprofloxacin, clinafloxacin, gatifloxacin, levofloxacin, moxifloxacin, and trovafloxacin against Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter cloacae, and Enterobacter aerogenes clinical isolates with alterations in GyrA and ParC proteins; Brisse S et al.; The in vitro activities of ciprofloxacin, clinafloxacin, gatifloxacin, levofloxacin, moxifloxacin, and trovafloxacin were tested against 72 ciprofloxacin-resistant and 28 ciprofloxacin-susceptible isolates of Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter cloacae, and Enterobacter aerogenes . Irrespective of the alterations in GyrA and ParC proteins, clinafloxacin exhibited greater activity than all other fluoroquinolones tested against K . pneumoniae and E . aerogenes. Appl Environ Microbiol, 1999 Aug, 65(8), 3458 - 63 Production of acylated homoserine lactones by psychrotrophic members of the Enterobacteriaceae isolated from foods; Gram L et al.; Bacteria are able to communicate and gene regulation can be mediated through the production of acylated homoserine lactone (AHL) signal molecules . These signals play important roles in several pathogenic and symbiotic bacteria . The following study was undertaken to investigate whether AHLs are produced by bacteria found in food at temperatures and NaCl conditions commercially used for food preservation and storage . A minimum of 116 of 154 psychrotrophic Enterobacteriaceae strains isolated from cold-smoked salmon or vacuum-packed chilled meat produced AHLs . Analysis by thin-layer chromatography indicated that N-3-oxo-hexanoyl homoserine lactone was the major AHL of several of the strains isolated from cold-smoked salmon and meat . AHL-positive strains cultured at 5 degrees C in medium supplemented with 4% NaCl produced detectable amounts of AHL(s) at cell densities of 10(6) CFU/ml . AHLs were detected in cold-smoked salmon inoculated with strains of Enterobacteriaceae stored at 5 degrees C under an N(2) atmosphere when mean cell densities increased to 10(6) CFU/g and above . Similarly, AHLs were detected in uninoculated samples of commercially produced cold-smoked salmon when the level of indigenous Enterobacteriaceae reached 10(6) CFU/g . This level of Enterobacteriaceae is often found in lightly preserved foods, and AHL-mediated gene regulation may play a role in bacteria associated with food spoilage or food toxicity. Int J Syst Bacteriol, 1999 Jul, 49 Pt 3, 941 - 51 Complex genomic and phenotypic characterization of the related species Staphylococcus carnosus and Staphylococcus piscifermentans; Pantucek R et al.; On the basis of numerical analysis of 100 phenotypic features, the strains of two species, Staphylococcus carnosus and Staphylococcus piscifermentans, were differentiated into two separate phenons corresponding with the macrorestriction patterns of their genomic DNA, as well as with the results of ribotyping and PCR amplification of enterobacterial repetitive intergenic consensus sequences . One of the S . carnosus strains, the F-2 strain, was shown to be marginal, exhibiting the lowest genomic and phenotypic similarity to the S . carnosus type strain DSM 20501T . Two of the strains studied (strains S . carnosus SK 06 and S . piscifermentans SK 05) were phenotypically convergent, forming a separate phenon . They were phenotypically similar, even though the genomic DNA of one of them was homologous with that of the S . carnosus type strain, whereas that of the other was homologous with the genomic DNA of the S . piscifermentans type strain . In such cases, fingerprinting methods (particularly macrorestriction analysis and ribotyping) served as important correctives, as they allow phenotypically convergent strains to be distinguished on the basis of their genomic profiles . The results of this paper support the proposal for the new species Staphylococcus condimenti as well as the new subspecies Staphylococcus carnosus subsp . utilis. Lik Sprava, 1999 Jan-Feb, (1), 33 - 5 {The use of the natural mineral saponite for water decontamination}; Hyrin VM et al.; Sorption properties were studied of natural and activated specimens of saponite with respect to poliomyelitis virus, Coxsackie B 1 and B 6 viruses as well as to Enterobacteriaceae group bacteria . With the purpose of comparing the processes of sorption of microorganisms, other minerals were also used, such as bentonite, alunite, glauconite, ceolite . The natural saponite adsorptive properties were found out to undergo changes during the process of thermoactivation . Mechanisms are discussed of a decontaminating effect of thermoactivated saponite in water. Antonie Van Leeuwenhoek, 1999 Jan-Feb, 75(1-2), 135 - 41 Molecular genetics of carbapenem antibiotic biosynthesis; McGowan SJ et al.; Carbapenems are potent beta-lactam antibiotics with a broad spectrum of activity against both Gram positive and Gram negative bacteria . As naturally produced metabolites, they have been isolated from species of Streptomyces, Erwinia and Serratia . The latter two members of the Enterobacteriaceae have proved to be genetically amenable and a growing body of research on these organisms now exists concerning the genes responsible for carbapenem biosynthesis and the regulatory mechanisms controlling their expression . A cluster of nine carbapenem (car) genes has been identified on the chromosome of Erwinia carotovora . These genes encode the enzymes required for construction of carbapenem and the proteins responsible for a novel beta-lactam resistance mechanism, conferring carbapenem immunity in the producing host . Although sharing no homology with the well known enzymes of penicillin biosynthesis, two of the encoded proteins are apparently similar to enzymes of the clavulanic acid biosynthetic pathway implying a common mechanism for construction of the beta-lactam ring . In addition, a transcriptional activator is encoded as the first gene of the carbapenem cluster and this allows positive expression of the remaining downstream genes in response to a quorum sensing, N-acyl homoserine lactone, signalling molecule. Eur J Clin Microbiol Infect Dis, 1999 May, 18(5), 330 - 4 Home intravenous antibiotic therapy for patients with infective endocarditis; Huminer D et al.; Although home intravenous antibiotic therapy (HIAT) is increasingly being used for various infectious diseases, outpatient treatment of infective endocarditis (IE) is still uncommon . Recently, the American Heart Association recommended outpatient treatment of endocarditis only for infections with streptococci that are highly susceptible to penicillin . Herein, the experience with HIAT in patients with IE due to a diversity of pathogens is presented . During a 3-year period, 37 patients with IE who were in a stable condition and were cooperative were enrolled in a service for HIAT after completion of diagnostic procedures . Of the 37 patients, 21 were male; mean age was 64.3 years (range 20-87 years); in most cases (26/37), IE involved a native valve . Causative organisms were Streptococcus spp . (20), Staphylococcus spp . (10), Enterococcus spp . (2), Enterobacter spp . (1), and Erysipelothrix rhusiopathiae (1), while three were unknown . The most common antibiotics used were ceftriaxone and vancomycin . Almost three-quarters of the intravenous lines were peripheral . The mean duration of HIAT was 26.2 +/- 8.5 days, with 92% of the patients cured by it . Most complications were minor . Six patients were rehospitalised and two of them required valve replacement . In half of the rehospitalised patients, the complication was unrelated to HIAT . Surprisingly, almost all of the complications necessitating rehospitalisation occurred in patients with streptococcal IE and most involved native valves . HIAT may be suitable for IE due to a diversity of pathogens and involving prosthetic as well as native heart valves, provided there are proper patient and antibiotic selections, good follow-up, and vigilant monitoring of complications. Mikrobiologiia, 1999 Mar-Apr, 68(2), 149 - 54 {FMN-reductase from Escherichia coli and its effect on the activity of luciferase from marine bacterium Vibrio fischeri}; Mazhul' MM et al.; Interactions of luciferases isolated from Vibrio fischeri 6 and Escherichia coli JM109(pF3) (bearing cloned V . fischeri luxAB genes) with FMN reductase isolated from E . coli JM109 were studied . FMN reductase formed a stable complex with luciferase, suggesting similar properties of the FMN reductases in the taxonomically close families Vibrionaceae and Enterobacteriaceae. J Food Prot, 1999 Apr, 62(4), 398 - 402 Biogenic amines and sensory changes associated with the microbial flora of Mediterranean gilt-head sea bream (Sparus aurata) stored aerobically at 0, 8, and 15 degrees C; Koutsoumanis K et al.; Changes in the concentrations of tyramine, agmatine, putrescine, cadaverine, spermidine, tryptamine, spermine, histamine, and trimethylamine were studied in parallel with the development of the microbial population during the storage of Mediterranean gilt-head sea bream (Sparus aurata) at three temperatures (0, 8, 15 degrees C) . Changes in sensory scores were also recorded . Pseudomonads and H2S-producing bacteria were the dominant microorganisms . Enterobacteriaceae and lactic acid bacteria were also present in the fish microflora . Among the biogenic amines, putrescine and cadaverine were detected when pseudomonads exceeded 10(6) to 10(7) CFU/g . Histamine was produced only in samples stored at 15 degrees C . Tyramine, tryptamine, agmatine, and trimethylamine were absent regardless of the storage temperature. Int J Antimicrob Agents, 1999 Jul, 12(2), 129 - 34 Selection of resistant variants of respiratory pathogens by quinolones; Sefton AM et al.; Quinolones are widely used in the treatment of respiratory tract infections . However, some disquiet has been expressed over using quinolones for community-acquired pneumonia since their activity is generally rather poor against Streptococcus pneumoniae . In addition, it is known that resistant variants emerge at a fairly high frequency during exposure of Enterobacteriaceae to quinolones; if this also occurred during quinolone treatment of community-acquired pneumonia it could lead to an increased risk of clinical failure . We therefore determined the selection rate of quinolone-resistant variants for six strains of S . pneumoniae, Haemophilus influenzae and Moraxella catarrhalis with nalidixic acid (except for S . pneumoniae), ciprofloxacin, ofloxacin and levofloxacin . We were only able to select resistant variants at low frequency from two of the six strains of S . pneumoniae with ciprofloxacin: no resistant variants were selected by either ofloxacin or levofloxacin . Variants of H . influenzae and M . catarrhalis with decreased susceptibility to quinolones were produced both with more strains and with a greater frequency; however, these variants still remained susceptible according to the NCCLS guidelines . Our study suggests that resistant variants of S . pneumoniae are relatively unlikely to occur in individuals treated with fluoroquinolones especially if they are given quinolones with enhanced anti-gram-positive activity compared to ciprofloxacin. FEMS Microbiol Lett, 1999 Jul 1, 176(1), 11 - 5 Penetration of beta-lactamase inhibitors into the periplasm of gram-negative bacteria; Farmer TH et al.; The effectiveness of a beta-lactamase inhibitor/beta-lactam combination against Gram-negative pathogens depends on many interplaying factors, one of which is the penetration of the inhibitor across the outer membrane . In this work we have measured the relative penetrations of clavulanic acid, sulbactam, tazobactam and BRL 42715 into two strains of Escherichia coli producing TEM-1 beta-lactamase, two strains of Klebsiella pneumoniae producing either TEM-1 or K-1, and two strains of Enterobacter cloacae each producing a Class C beta-lactamase . It was shown that clavulanic acid penetrated the outer membranes of all these strains more readily than the other beta-lactamase inhibitors . For the strains of E . coli and K . pneumoniae clavulanic acid penetrated approximately 6 to 19 times more effectively than tazobactam, 2 to 9 times more effectively than sulbactam and 4 to 25 times more effectively than BRL 42715 . The superior penetration of clavulanic acid observed in this study is likely to contribute to the efficacy of clavulanic acid/beta-lactam combinations in combating beta-lactam resistant bacterial pathogens. Pathol Biol (Paris), 1999 May, 47(5), 437 - 9 Emergence of multidrug-resistant Enterobacter cloacae: nosocomial outbreak or change of microbial ecology? Honderlick P, Saheb F, Cahen P. Frequent selection of mutants resistant to extended and broad spectrum cephalosporins in Enterobacter cloacae is observed in hospital . As we noticed an unusual number of isolates of these strains and to answer the question arose whether these Enterobacter had a common source, we retrospectivally studied 56 strains collected in 11 wards of the hospital . Using PFGE with Spe 1 restriction analysis we identified a prevalent clone (11 patients) dispatched in 8 wards . We also obviously proved cross-contamination patients to patients with other clones . PFGE allow us to point out that clonal Enterobacter cloacae has taken place in our hospital, even if there is no real outbreak . A reinforcement of basic hygienic measures and a control of antibiotics prescription seemed very important to jugulate the sudden increase of multiresistant Enterobacter cloacae prevalence. Mol Microbiol, 1999 Aug, 33(3), 590 - 8 Na+ translocation by the NADH:ubiquinone oxidoreductase (complex I) from Klebsiella pneumoniae; Krebs W et al.; Complex I is the site for electrons entering the respiratory chain and therefore of prime importance for the conservation of cell energy . It is generally accepted that the complex I-catalysed oxidation of NADH by ubiquinone is coupled specifically to proton translocation across the membrane . In variance to this view, we show here that complex I of Klebsiella pneumoniae operates as a primary Na+ pump . Membranes from Klebsiella pneumoniae catalysed Na+-stimulated electron transfer from NADH or deaminoNADH to ubiquinone-1 (0.1-0.2 micromol min-1 mg-1) . Upon NADH or deaminoNADH oxidation, Na+ ions were transported into the lumen of inverted membrane vesicles . Rate and extent of Na+ transport were significantly enhanced by the uncoupler carbonylcyanide-m-chlorophenylhydrazone (CCCP) to values of approximately 0.2 micromol min-1 mg-1 protein . This characterizes the responsible enzyme as a primary Na+ pump . The uptake of sodium ions was severely inhibited by the complex I-specific inhibitor rotenone with deaminoNADH or NADH as substrate . N-terminal amino acid sequence analyses of the partially purified Na+-stimulated NADH:ubiquinone oxidoreductase from K . pneumoniae revealed that two polypeptides were highly similar to the NuoF and NuoG subunits from the H+-translocating NADH:ubiquinone oxidoreductases from enterobacteria. Arch Latinoam Nutr, 1999 Mar, 49(1), 76 - 80 {Microbiological quality of pasteurized milk creams manufactured in Venezuela}; Szwarcbort de Tamsut L et al.; A total of 100 samples of pasteurized milk creams produced by eleven (11) dairy milk industries were analyzed for the presence of microoganisms . The dairy milk industries were distributed along different places of Venezuela . The samples were analyzed for the presence of mesophilic aerobic bacteria, psychotropic bacteria, Staphylococcus aureus, coliformes, molds and yeasts 75% of the analyzed samples did not reach the international standards for aerobic mesophilic bacteria, similarly, 95% for Staphylococcus aureus, 91% for coliformes and 58% for molds and yeasts, so pathogenic enterobacteria we have found: Salmonella Typhimurium, Shigella sonnei and Escherichia coli enteropathogenic. Pneumologie, 1999 Apr, 53(4), 199 - 206 {Inpatient treatment costs of exacerbated chronic obstructive lung disease}; Riecke K et al.; Economic aspects are of increasing importance in health care . However, treatment expenditures for most diseases are unknown . We performed a detailed cost analysis for the treatment of the exacerbated chronic obstructive pulmonary disease (ECOPD) in our department . For one year, all patients admitted because of exacerbated chronic obstructive pulmonary disease were included in this study . The workload was assessed for each patient by time keeping . Diagnostic and therapeutic procedures were considered according to the price list of the German hospital association . From 101 patients included into the study, 100 were evaluable . The median duration of inpatient hospitalisation amounted to 18 days (range: 4 to 210 days) . Median total cost was DM 7680.- and mean cost DM 11900.- . This consisted of non-medical cost items (36%), personnel expenditures (29%), laboratory tests (14%), respiratory and cardiovascular laboratory (7%), radiology (5%) and pharmacy cost (7%) . Endoscopy, external diagnostics and medical reports amounted to 2.8% of the expenditure . Treatment cost correlated with the duration of stay, but hardly with lung function and blood gases, these being independent of age and sex, but significantly higher in case of bronchiectasis, enterobacteriae, cor pulmonale or intensive care . The proportion of the pharmacy expenditures was rather small, and hence this is not a primary target for the realisation of major savings. J Clin Microbiol, 1999 Aug, 37(8), 2488 - 92 Value of enterobacterial repetitive intergenic consensus PCR for study of Pasteurella multocida strains isolated from mouths of dogs; Loubinoux J et al.; Fifty-six Pasteurella multocida strains (40 P . multocida subsp . septica and 16 P . multocida subsp . multocida strains) isolated from the mouths of 56 dogs among the 134 living in a French canine military training center (132e Groupe Cynophile de l'Armee de Terre, Suippes, France) were studied by use of enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) and restriction fragment length polymorphism (RFLP) techniques . Both techniques showed genomic heterogeneity of the strains studied . However, RFLP was more discriminatory than ERIC-PCR for differentiating P . multocida strains . All but three pairs of strains were discriminated by RFLP, suggesting a limited circulation of strains between these dogs living in proximity . Although ERIC-PCR is easier and faster to perform, it cannot be recommended for epidemiological studies of P . multocida strains. J Clin Microbiol, 1999 Aug, 37(8), 2473 - 8 Comparison of molecular methods for typing Vibrio parahaemolyticus; Marshall S et al.; An outbreak of Vibrio parahaemolyticus gastroenteritis on Canada's west coast in 1997 emphasized the need to develop molecular methods for differentiation and typing of these organisms . Isolates were analyzed by enterobacterial repetitive intergenic consensus sequence (ERIC) PCR, detection of restriction fragment length polymorphisms (RFLP) in rRNA genes (ribotyping), pulsed-field gel electrophoresis (PFGE), and RFLP analysis of the genetic locus encoding the polar flagellum (Fla locus RFLP analysis) . ERIC PCR and ribotyping were the most informative typing methods, especially when used together, while Fla locus RFLP analysis was the least discriminatory . PFGE exhibited good discrimination but suffered from a high incidence of DNA degradation . ERIC PCR and ribotyping will be useful for the evaluation of genetic and epidemiological relationships among V . parahaemolyticus strains. Arch Pharm Res, 1999 Jun, 22(3), 274 - 8 Expression of the recombinant Klebsiella aerogenes UreF protein as a MalE fusion; Kim KY et al.; Expression of the active urease of the enterobacterium, Klebsiella aerogenes, requires the presence of the accessory genes (ureD, ureE, ureF, and ureG) in addition to the three structural genes (ureA, ureB, and ureC) . These accessory genes are involved in functional assembly of the nickel-metallocenter for the enzyme . Characterization of ureF gene has been hindered, however, since the UreF protein is produced in only minute amount compared to other urease gene products . In order to overexpress the ureF gene, a recombinant pMAL-UreF plasmid was constructed from which the UreF was produced as a fusion with maltose-binding protein . The MBP-UreF fusion protein was purified by using an amylose-affinity column chromatography followed by an anion exchange column chromatography . Polyclonal antibodies raised against the fusion protein were purified and shown to specifically recognize both MBP and UreF peptides . The UreF protein was shown to be unstable when separated from MBP by digestion with factor Xa. Pharmazie, 1999 Jun, 54(6), 460 - 3 Comparative study on the in vitro antibacterial activity of Australian tea tree oil, cajuput oil, niaouli oil, manuka oil, kanuka oil, and eucalyptus oil; Harkenthal M et al.; To compare the antibacterial activity of the Australian tea tree oil (TTO) with various other medicinally and commercially important essential myrtaceous oils (cajuput oil, niaouli oil, kanuka oil, manuka oil, and eucalyptus oil) the essential oils were first analysed by GC-MS and then tested against various bacteria using a broth microdilution method . The highest activity was obtained by TTO, with MIC values of 0.25% for Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Salmonella choleraesuis, Shigella flexneri, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, S . saprophyticus, and S . xylosus . It is noteworthy that manuka oil exhibited a higher activity than TTO against gram-positive bacteria, with MIC values of 0.12% . Both TTO and manuka oil also demonstrated a very good antimicrobial efficacy against various antibiotic-resistant Staphylococcus species . Pseudomonas aeruginosa was resistant to all essential oils tested, even at the highest concentration of 4%. Arch Microbiol, 1999 Jul, 172(1), 22 - 30 Genetic basis of enterobacterial repetitive intergenic consensus (ERIC)-PCR fingerprint pattern in Sinorhizobium meliloti and identification of S . meliloti employing PCR primers derived from an ERIC-PCR fragment; Niemann S et al.; The enterobacterial repetitive intergenic consensus (ERIC)-PCR method was employed to generate genomic amplification products of Sinorhizobium meliloti strain 2011 . Eleven distinctive PCR fragments obtained in PCR reactions by using the ERIC2 primer were cloned and their partial or complete nucleotide sequences established . DNA sequences that extended past the ERIC2 primer region were not conserved among the 11 PCR fragments and showed no sequence similarity to the enterobacterial ERIC consensus sequence . Thus, repetitive ERIC or ERIC-like sequences seem not to be an integral part of the S . meliloti genome . An amplification product of S . meliloti 2011 was identified which was present in S . meliloti strains but absent in other rhizobial species . Based on the nucleotide sequence information, a pair of PCR primers was designed and used for PCR amplification of sequences of S . meliloti laboratory strains 2011, L5-30, AK631 and 102F34 . Nucleotide sequence analysis of the amplification products revealed a 100% DNA sequence conservation . Database searches showed that the DNA fragment putatively encodes the C-terminal part of a protein displaying similarity to 2-hydroxyacid dehydrogenases of various organisms . The newly designed PCR primers should be useful for the rapid identification of S . meliloti isolates. Acta Biochim Pol, 1998, 45(4), 1011 - 9 Immunochemical studies on R mutants of Yersinia enterocolitica O:3; Radziejewska-Lebrecht J et al.; Three mutants of Yersinia enterocolitica O:3, namely: YeO3-R1, YeO3-RfbR7 and YeO3-c-trs8-R were classified on the basis of sodium dodecyl sulphate/polyacrylamide gel electrophoresis (SDS/PAGE) profile of isolated lipopolysaccharides (LPS) as belonging to the Ra- (the first) and the Rc-type (the other two mutants) . Methylation analysis, in addition to 13C and 1H NMR studies of purified core oligosaccharides revealed structures similar to those established previously for the full core of Y . enterocolitica O:3 in the case of the Ra mutant, and identical to that reported for the Rc mutant Ye75R, in the case of the two other mutants . The O-specific sugar, 6d-L-altrose, which forms a homopolymeric O-chain, was present in small amounts in all three LPS preparations, as well as in the core oligosaccha ride preparations along with the Ra and the Rc sugars, characteristic of the Y . enterocolitica O:3 core . This result is in line with genetic data, indicating that it is the inner core region which is the receptor for the O-specific chain in Y . enterocolitica O:3 . This region seems likewise to be the anchoring region for the enterobacterial common antigen (ECA), as shown by SDS/PAGE/Western blot analysis with monoclonal antibodies against ECA . In addition, we also demonstrated that the Ye75R mutant Rc and its parental strain Ye75S, both were ECA-immunogenic strains . So far, ECA-immunogenic strains, i.e . those with LPS-linked ECA, were only identified in E . coli mutants of the R1, R4 and K-12 serotype. Int J Antimicrob Agents, 1999 May, 11(3-4), 305 - 8 The prevalence of antimicrobial resistance among uropathogens causing acute uncomplicated cystitis in young women; Gupta K et al.; Four hundred and fifty-two urine isolates from women with acute uncomplicated cystitis and a positive urine culture presenting to a sexually transmitted disease clinic were collected during 1989-1991, and 213 specimens were collected over 1995-1997 . The predominant species was Escherichia coli, representing 68% of the isolates; others included Staphylococcus saprophyticus (8%), Group B streptococci (7%), Proteus spp . (6%), Klebsiella spp . (4%) and Enterococcus spp.(3%) . More than 10% of the E . coli isolates were resistant to ampicillin, cephalothin, tetracycline and trimethoprim sulfamethoxazole (TMP SMX ) during both study periods, with the greatest increase in resistance to ampicillin and TMP/SMX between the two periods . Six hundred and four urinary tract infection isolates, including 83% E . coli, 7% S . saprophyticus, 3%, Klebsiella spp . 2% Proteus spp., 2% enterococci, 1% Enterobacter spp . and 2% other organisms, were collected from women with acute cystitis attending a university student health service during 1995 . Among E . coli isolates, 25% were resistant to ampicillin, 24% to tetracycline and 11%, to TMP SMX . Resistance to fluoroquinolones was essentially absent among gram-negative pathogens . Continued evaluation of susceptibility patterns of pathogens causing acute uncomplicated cystitis to traditional as well as new antimicrobials in well defined populations is necessary to ascertain the optimal empiric therapy. Klin Med (Mosk), 1999, 77(5), 27 - 31 {Population study of antibodies to some potential pathogens of spondyloarthopathies: the study of the Chukotka population}; Guseva IA et al.; The paper presents the results of the study of specific immune response stimulated by some enterobacteria in populations with high incidence of HLA-B27 . A, M and G antibodies to Yersinia, Clebsiella, Salmonella and Campilobacter were studied on 292 plasma samples . The levels of the antibodies varied with anthropological parameters of the examinees (gender, age, nationality) . The presence of the gene HLA-B27 in the genotype levels gender dimorphism of the specific humoral immune response . This may be of importance in pathogenesis of spondyloarthropathies which occur more frequently in men. Proc Natl Acad Sci U S A, 1999 Jul 6, 96(14), 8110 - 5 The mast cell tumor necrosis factor alpha response to FimH-expressing Escherichia coli is mediated by the glycosylphosphatidylinositol-anchored molecule CD48; Malaviya R et al.; Mast cells are well known for their harmful role in IgE-mediated hypersensitivity reactions, but their physiological role remains a mystery . Several recent studies have reported that mast cells play a critical role in innate immunity in mice by releasing tumor necrosis factor alpha (TNF-alpha) to recruit neutrophils to sites of enterobacterial infection . In some cases, the mast cell TNF-alpha response was triggered when these cells directly bound FimH on the surface of Escherichia coli . We have identified CD48, a glycosylphosphatidylinositol-anchored molecule, to be the complementary FimH-binding moiety in rodent mast cell membrane fractions . We showed that (i) pretreatment of mast cell membranes with antibodies to CD48 or phospholipase C inhibited binding of FimH+ E . coli, (ii) FimH+ E . coli but not a FimH- derivative bound isolated CD48 in a mannose-inhibitable manner, (iii) binding of FimH+ bacteria to Chinese hamster ovary (CHO) cells was markedly increased when these cells were transfected with CD48 cDNA, and (iv) antibodies to CD48 specifically blocked the mast cell TNF-alpha response to FimH+ E . coli . Thus, CD48 is a functionally relevant microbial receptor on mast cells that plays a role in triggering inflammation. Biochem J, 1999 Jul 15, 341 ( Pt 2), 409 - 13 Peptidase activity of beta-lactamases; Rhazi N et al.; Although beta-lactamases have generally been considered as being devoid of peptidase activity, a low but significant hydrolysis of various N-acylated dipeptides was observed with representatives of each class of beta-lactamases . The kcat/Km values were below 0.1 M(-1) . s(-1), but the enzyme rate enhancement factors were in the range 5000-20000 for the best substrates . Not unexpectedly, the best 'peptidase' was the class C beta-lactamase of Enterobacter cloacae P99, but, more surprisingly, the activity was always higher with the phenylacetyl- and benzoyl-d-Ala-d-Ala dipeptides than with the diacetyl- and alpha-acetyl-l-Lys-d-Ala-d-Ala tripeptides, which are the preferred substrates of the low-molecular-mass, soluble dd-peptidases . A comparison between the beta-lactamases and dd-peptidases showed that it might be as difficult for a dd-peptidase to open the beta-lactam ring as it is for the beta-lactamases to hydrolyse the peptides, an observation which can be explained by geometric and stereoelectronic considerations. Antimicrob Agents Chemother, 1999 Jul, 43(7), 1759 - 60 Sequence of the MIR-1 beta-lactamase gene; Jacoby GA et al.; The complete nucleotide sequence of the plasmid-mediated MIR-1 beta-lactamase gene confirms its relationship to chromosomally located ampC genes of Enterobacter cloacae . blaMIR-1 is not part of a typical gene cassette but does lie near an element that could be involved in its capture on a plasmid. Antimicrob Agents Chemother, 1999 Jul, 43(7), 1743 - 6 Class C beta-lactamases operate at the diffusion limit for turnover of their preferred cephalosporin substrates; Bulychev A et al.; It has been suggested that class C beta-lactamases have evolved to carry out a metabolic reaction other than hydrolysis of beta-lactam antibiotics . It is demonstrated in the present study that the class C beta-lactamase from Enterobacter cloacae P99 has reached the diffusion limit in its ability to hydrolyze its preferred cephalosporin substrates . The increase in the solution viscosity by addition of a microviscogen (sucrose) caused the decline in the parameter kcat/Km for hydrolysis of cephaloridine and cephalosporin C (approximately 2.5-fold at a relative viscosity of 2.9) . A similar increase in viscosity has no effect on the turnover rate of the poorer substrates cefepime and penicillin G . Addition of a macroviscogen (polyethylene glycol) to the reaction mixture did not change the rate of turnover for any of the substrates tested because in this case the viscogen would not interfere with the motion of small molecules, as was expected . Therefore, it would appear that the driving force behind the evolution of this class C beta-lactamase and, in principle, other enzymes of this class is indeed the functional reaction of this enzyme as a drug resistance factor. Int J Antimicrob Agents, 1999 Jun, 12(1), 33 - 9 In vitro activity of clinafloxacin against fluoroquinolone resistant Spanish clinical isolates; Lopez-Brea M et al.; The in vitro activity of clinafloxacin against 162 ciprofloxacin-resistant clinical isolates was determined . Isolates were selected when their MIC to ciprofloxacin was 2 mg/l (intermediate) or > 2 mg/l (resistant) . The following strains were tested: 61 Escherichia coli, 12 Klebsiella pneumoniae, 7 Proteus mirabilis, 21 Serratia marcescens, 4 Enterobacter cloacae, 21 Pseudomonas aeruginosa, 21 Staphylococcus . aureus (resistant to methicillin) and 15 Enterococcus spp . Clinafloxacin, ciprofloxacin, ofloxacin and norfloxacin activities were evaluated by agar dilution using Mueller-Hinton agar according to NCCLS recommendations . Of the 162 isolates, 16 (9.8%) were intermediate and 146 (90.1%) resistant to ciprofloxacin . 95 of the 162 strains (58.6%) were susceptible, 27 (16.7%) intermediately susceptible, and 40 strains (24.7%) were resistant to clinafloxacin . The percentage susceptible to clinafloxacin was 65.6% for E . coli, 75% for K . pneumoniae, 71.4% for P . mirabilis, 28.6% for S . marcescens, 75% for E . cloacae, 33.3% for P . aeruginosa, 90.5% for S . aureus and 40% for Enterococcus spp . Clinafloxacin was active against 58.6% of the ciprofloxacin-resistant clinical isolates tested . It was particularly active against S . aureus strains resistant to both ciprofloxacin and methicillin. An Med Interna, 1999 May, 16(5), 236 - 8 {Urinary tract infection and antibiotic sensitivity in the south of Albacete, Spain}; Atienza Morales MP et al.; OBJECTIVES: Describing the bacteriological map of the urinary tract infections (UTI) in our area including intra and extrahospitalized patients during 1997 . MATERIAL AND METHODS: Descriptive-retrospective study, 12,937 urocultives were carried out in our laboratory: 847 from hospitalized patients and 12,090 from 15 Health Centres . RESULTS: 1,527 positive cultures (12.6%) were obteined from Health Centre patients and 215 (25.3%) from hospitalized patients . Bacterial distribution was similar between them, except enterocci and negative coagulase estafilococci which were more frequent in hospitalized patients . We have observed a high prevalence of Enterobacter sp . (4%) and Pseudomonas sp . (4%) which disagrees with other studies . E.coli (presents in 69% of the positive urocultives) was widespread resistant to quinolones, pipemidic acid and nitrofuration, while it had high sensitivity to fosfomicin, cephuroxim and amoxicilin-clavulanic acid . CONCLUSIONS: The level of resistance to the quinolones is considerable in our area, so clinicians should give them up in empirical treatment and use fosfomicine, cephuroxime or amoxicilin-clavulanic acid. Kansenshogaku Zasshi, 1999 May, 73(5), 429 - 36 {A trial of povidone-iodine (PVP-I) nasal inhalation and gargling to remove potentially pathogenic bacteria colonized in the pharynx}; Kawana A et al.; OBJECTIVE: Aspiration of potentially pathogenic bacteria (PPB) colonized in the upper airway is a major cause of bacterial pneumonia . We hypothesized that PVP-I nasal inhalation is effective in removing PPB from the upper airway . The aim of this study was to investigate the effectiveness and safety of PVP-I nasal inhalation . METHODS: Patients with asymptomatic PPB (MRSA and/or aerobic GNB i.e . Pseudomonas aeruginosa, Enterobacteriaceae) colonization in the pharynx were enrolled in this study . These patients were divided randomly into two groups as follows: a PVP-I nasal inhalation group (N group) which was asked to inhale 1% PVP-I solution x 2/day nasally by a jet nebulizer and gargling with PVP-I solution x 2/day, and a control group (C group), which was asked to gargle with PVP-I solution x 2/day . The study period was 2 weeks in both groups . RESULTS: Group N consisted of 16 cases, which included 9 (56%) cases with chronic respiratory complications and group C consisted of 14 cases which included 6 (43%) cases with complications . In N and C group, PPB disappearance from the pharynx was observed in 44% and 14% of patients after the study period, respectively . In the patients of group N, without chronic respiratory complication, PPB disappeared in 86% ot the cases . There was no adverse effect correlated with PVP-I nasal inhalation . CONCLUSION: We conclude that PVP-I nasal inhalation is a safe procedure for removing PPB from the upper airway, and this method may contribute to preventing bacterial pneumonia. Eur J Clin Microbiol Infect Dis, 1999 Apr, 18(4), 305 - 9 Antibacterial activity of moxifloxacin (Bay 12-8039) against aerobic clinical isolates, and provisional criteria for disk susceptibility tests; Barry AL et al.; Moxifloxacin (Bay 12-8039), ciprofloxacin, and levofloxacin were compared in vitro against 1074 clinical isolates gathered from different medical centers throughout North America during the winter months of 1997 . Moxifloxacin E tests and broth microdilution tests gave comparable results . Moxifloxacin was particularly potent against respiratory pathogens such as Haemophilus influenzae and Streptococcus pneumoniae . Ciprofloxacin was the most potent study drug against the family of Enterobacteriaceae and Pseudomonas spp . For tests of 5 microg moxifloxacin disks, zone size criteria of < or = 17 mm for resistant (MIC > or = 8 microg/ml) and > or = 21 mm for susceptible (MIC < or = 2 microg/ml) are provisionally proposed for use while clinical trials are under way. J Antimicrob Chemother, 1999 May, 43(5), 703 - 6 In-vitro antimicrobial activity of a carbapenem, MK-0826 (L-749,345) and provisional interpretive criteria for disc tests; Fuchs PC et al.; The in-vitro activity of MK-0826, a new oral carbapenem, was compared with that of imipenem by broth microdilution susceptibility tests against 545 bacterial isolates . MK-0826 had significantly greater activity against Enterobacteriaceae and poorer activity against Pseudomonas aeruginosa and many gram-positive species . MK-0826 disc diffusion tests were also performed according to the NCCLS procedure and tentative interpretive criteria were determined for possible susceptible MIC breakpoints of < or = 4.0 and < or = 2.0 mg/L. J Food Prot, 1999 Jun, 62(6), 615 - 8 Antimicrobial resistance of bacterial flora associated with bovine products in South Africa; Manie T et al.; The administration of subtherapeutic doses of antibiotics to livestock introduces selective pressures that may lead to the emergence and dissemination of resistant bacteria . This study determined the antibiotic-resistance spectra of the microbial flora found on freshly slaughtered and retail beef and in unpasteurized and pasteurized packaged milk . Staphylococci, Enterobacteriaeae, and isolates from total aerobic plate counts were tested for resistance to vancomycin, streptomycin, methicillin, tetracycline, and gentamicin using the disc diffusion susceptibility test and resistance to penicillin was determined by using oxacillin . A larger proportion of resistance to most antibiotics, except for vancomycin, was displayed by isolates from abattoir samples . The incidence of multiple antibiotic resistance (MAR) pathogenic bacteria is also higher in the abattoir . Resistance genes lost because of lack of selective pressure or resistant flora being replaced by more sensitive flora during processing is the reason for the lower incidence of MAR pathogenic bacteria among retail samples . These resistant bacteria can be transferred to humans through the consumption of rare or raw beef and unpasteurized milk, thus rendering the resultant food-related infections difficult to treat . The present findings clearly demonstrate that antibiotic-resistant bacteria in beef and milk pose a serious problem in South Africa. Antibiot Khimioter, 1999, 44(3), 15 - 8 {Investigation and identification of the antimicrobial component of the drug "Tomatol"}; Vorob'ev AA et al.; Antimicrobial activity of Tomatol against laboratory strains of Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538-P and Candida albicans ATCC 885-653 as well as against clinical isolates of Enterobacter spp., Streptococcus spp., Staphylococcus spp., Klebsiella spp . and Escherichia spp . was tested . Tomatol was shown to have a broad antimicrobial spectrum including gram-positive and gram-negative organisms and Candida . The TLC investigation demonstrated that the Tomatol antimicrobial component was that of a complex of organic acids such as succinic, citric, tartaric and others. J Antimicrob Chemother, 1999 Jan, 43(1), 119 - 26 Risk of resistance related to antibiotic use before admission in patients with community-acquired bacteraemia; Pedersen G et al.; We analysed the association of antibiotic therapy before admission and antibiotic resistance of blood isolates in a total of 1717 community-acquired bacteraemias in the County of Northern Jutland during 1992-96 . Antibiotics had been prescribed to 14% of the patients during the 30 days before admission and to 37% during the 6 months . The most frequently prescribed antibiotics within 30 days were ampicillin (28%), penicillin G (27%), sulphonamides and/or trimethoprim (16%) and macrolides (14%) . The most frequent blood isolates were Escherichia coli (33%), other Enterobacteriaceae (8%), Streptococcus pneumoniae (23%) and Staphylococcus aureus (10%) . Of the 575 isolates of E . coli, 425 (74%), 432 (75%) and 518 (90%) were susceptible to ampicillin, sulphonamides and trimethoprim, respectively . Previous antibiotic prescriptions were strongly associated with resistance to ampicillin, sulphonamides and trimethoprim in E . coli . The association was less pronounced for S . aureus and enteric rods other than E . coli . Antibiotic prescriptions within the last 3 months predicted antibiotic resistance, and this should be taken into account when selecting empirical antibiotic therapy of severe community-acquired infections. J Antimicrob Chemother, 1999 Jan, 43(1), 71 - 7 The post-exposure response of Enterobacteriaceae to ceftibuten; MacKenzie FM et al.; The responses of ten isolates of Enterobacteriaceae to ceftibuten exposure were monitored by measuring several parameters . Post-antibiotic effect (PAE), control-related effective regrowth time (CERT) and post-antibiotic sub-MIC effect (PA-SME) were determined by bacterial enumeration carried out either by impedance in combination with viable counting (IMP/VC) or by impedance in combination with bioluminescence (IMP/BIOL) . Kill curves were carried out by bioluminescence, viable counting and direct microscopy and post-exposure morphology was established . Ceftibuten primarily provoked filamentation . Over 24 h, kill of up to 3.6 log10 was evident by viable counting and direct microscopy at and above the MIC . Minimal kill, of up to 0.26 log10, was shown by bioluminescence . PAE was found to be method dependent, with statistical differences established by Student's t-test . PAE values of up to 0.48 h and 1.47 h (by IMP/BIOL and IMP/VC respectively) were not concentration dependent above 1 x MIC . CERT values were not method dependent, with values of up to 1.71 h also showing a lack of concentration dependence above 1 x MIC . PA-SME may reflect the situation in vivo more accurately than either PAE or CERT . In PAE and CERT studies the antibiotic is eliminated almost immediately, whereas in vivo there is gradual decrease in antibiotic levels . These persisting levels are reflected more accurately by PA-SME . Compared with PAE and CERT, significantly longer values, of up to 7.27 h, were obtained by PA-SME, although this parameter was also found to be method dependent . The results of the PA-SME studies, which may be the most clinically relevant pharmacodynamic parameter, confirm the appropriateness of the current once- or twice-daily dosing schedules despite the lack of PAE. J Antimicrob Chemother, 1999 Jan, 43(1), 55 - 60 Markedly different rates and resistance profiles exhibited by seven commonly used and newer beta-lactams on the selection of resistant variants of Enterobacter cloacae; Chan WC et al.; Seven beta-lactam antibiotics (cefepime, cefoperazone, ceftazidime, ceftriaxone, cefamandole, imipenem and meropenem) were tested for their potential to select resistance in standard and clinical strains of Enterobacter cloacae (n = 9) . The strains were subcultured daily with the test antibiotics at doubling concentrations starting at 0.125 x MIC . Development of resistance throughout the passages was detected by a disc diffusion test . Ceftazidime, ceftriaxone and cefamandole selected resistance at a faster rate than cefoperazone, cefepime and meropenem . Imipenem did not select resistance in the nine strains tested and was the only antibiotic that eradicated all the strains during selection . The resistance patterns of strains selected by meropenem, cefepime and the other cephalosporins were markedly different, although cross-resistance to the early generation cephalosporins was common . The resistance phenotypes of most strains remained stable upon serial passages in antibiotic-free medium . The findings of this study highlight the importance of the choice of antibiotic for therapy not only on the basis of its antibacterial activity, but also on its potential to select resistance to itself and other antibiotics. Can J Microbiol, 1999 Feb, 45(2), 162 - 71 Phenol degradation by an enterobacterium: a Klebsiella strain carries a TOL-like plasmid and a gene encoding a novel phenol hydroxylase; Heesche-Wagner K et al.; Although phenol catabolism is described for many different microorganisms, there is no example for such a pathway in an enterobacterial strain . Here we characterize a Klebsiella oxytoca strain that grows on phenol as the only source of carbon and energy . As the key enzyme of phenol degradation, phenol hydroxylase was purified to apparent homogeneity . Compared with other phenol hydroxylases, the Klebsiella enzyme differs with respect to several properties: (i) SDS-PAGE and gel-filtration analysis of the purified protein revealed that the enzyme is a monomer with a molecular mass of 156 kDa; (ii) steady-state kinetic measurements resulted in a K(m) value of 0.22 mM for phenol; and (iii) the enzyme is both dependent on NADPH/FAD and sensitive to EDTA . Further degradation of catechol, the reaction product of phenol hydroxylase, may occur via the effective meta-fission pathway often located on TOL or TOL-like plasmids . Such a plasmid was prepared from the Klebsiella strain and further characterized . The given data demonstrate that the isolated strain exhibits all characteristics of an efficient phenol-degrading microorganism. Pediatr Pulmonol, 1999 Jun, 27(6), 432 - 4 Nosocomial transmission of penicillin-resistant Streptococcus pneumoniae; Cimolai N et al.; Two patients were found to harbor intermediate-level penicillin-resistant Streptococcus pneumoniae in a pediatric hospital setting . For the first patient, the bacterium was isolated from a tracheal aspirate, and for the second patient, a positive blood culture was found a short time after the index case . Two molecular typing techniques (enterobacterial repetitive intergenic consensus sequence polymerase chain reaction, and repetitive sequence-based polymerase chain reaction) demonstrated homology among these isolates, which suggests person-to-person spread . We propose the need for institution-based infection control precautions that will limit the spread of penicillin-resistant pneumococci. Exp Anim, 1999 Apr, 48(2), 101 - 6 Establishment of specific pathogen-free rabbit colonies with limited-flora rabbits associated with conventional rabbit flora, and monitoring of their cecal flora; Yanabe M et al.; In the present study we attempted to establish specific-pathogen-free (SPF) rabbit breeding colonies with two groups of limited-flora (LF) rabbits, both ex-germfree rabbits, and their offspring . Two groups of LF rabbits associated with cecal flora of conventional (CV) rabbits produced in a previous study {Exp . Animals, submitted}, were transferred to individual barrier rooms and some of the LF rabbits were accommodated in isolators to maintain the basic flora for SPF rabbits . The composition of the cecal flora of LF rabbits was stable for a long period; bacteroides remained predominant and clostridia dominant . From the SPF rabbits, different types of bacteria, e.g., enterobacteriaceae and streptococci, which could not be isolated in the isolator were detected at a low population level at an early stage in the establishment of the SPF colonies, but the basic composition of the cecal flora was mainly bacteroidaceae and clostridia and did not change over a long period, and the floral composition became similar to that of CV rabbits . The fertility and weaning rates of the SPF rabbits were satisfactory for a SPF rabbit colony . In addition, these SPF colonies were free of more than one year rabbit-specific pathogens. J Clin Microbiol, 1999 Jul, 37(7), 2165 - 9 Most Enterobacter aerogenes strains in France belong to a prevalent clone; Bosi C et al.; The aim of this study was to determine the distribution in France of the Enterobacter aerogenes prevalent clone isolated in the hospitals of the Marseille area (A . Davin-Regli, D . Monnet, P . Saux, C . Bosi, R . Charrel, A . Barthelemy, and C . Bollet, J . Clin . Microbiol . 34:1474-1480, 1996) . A total of 123 E . aerogenes isolates were collected from 23 hospital laboratories and analyzed by random amplification of polymorphic DNA and enterobacterial repetitive intergenic consensus-PCR to determine their epidemiological relatedness . Molecular typing revealed that 21 of the 23 laboratories had isolated this prevalent clone harboring the plasmid encoding for extended-spectrum beta-lactamase of the TEM-24 type . Most isolates were susceptible only to imipenem and gentamicin . Their dissemination seems to be clonal and was probably the result of the general use of broad-spectrum cephalosporins and quinolones . Four isolates showed an alteration of their outer membrane proteins, causing decrease of susceptibility to third-generation cephalosporins and imipenem and leading to the critical situation of having no alternative therapeutic . The large dissemination of the E . aerogenes prevalent clone probably results from its good adaptation to the antibiotics administered in France and the hospital environment, particularly in intensive care units. J Med Microbiol, 1999 Jun, 48(6), 559 - 67 Phenotypic and genotypic typing of food and clinical isolates of Enterobacter sakazakii; Nazarowec-White M et al.; Enterobacter sakazakii, designated a unique species in 1980, has been implicated as the causative organism in a rare but severe form of neonatal meningitis . Dried infant formula milk has been identified as a potential source of the organism . E . sakazakii isolates from dried infant formula available in Canada and clinical isolates obtained from Canadian hospital culture collections were characterised by phenotypic (biotype and antibiograms) and genotypic (ribotyping, random amplification of polymorphic DNA and pulsed-field gel electrophoresis) methods . Three biotypes and four antibiogram patterns were observed in the 18 isolates examined . Ribotyping with the Dupont Riboprinter microbial identification system divided the 18 isolates into 10 ribotypes . Three isolates from the same hospital had indistinguishable ribotyping patterns although each was isolated in a different year, as did three food isolates from one company . Pulsed-field gel electrophoresis (PFGE) and random amplification of polymorphic DNA (RAPD) profiles indicated minor differences between the isolates that were indistinguishable by ribotyping . PFGE (with the restriction endonucleases Xba1 and Spe1) and RAPD gave discrete patterns that enabled easy comparison of E . sakazakii isolates, with a high degree of discrimination . The discriminatory index showed RAPD and PFGE were shown to be the most discriminatory typing schemes for E . sakazakii, followed by ribotyping, biotyping and antibiograms. Khirurgiia (Mosk), 1999, (5), 41 - 4 {Small intestine intubation for treatment of patients with peritonitis and intestinal obstruction}; Petrov VP et al.; The analysis of 36 case records of patients with peritonitis (n = 12) and intestinal obstruction (n = 24) is presented . Nasogastrointestinal intubation of the small bowel was used in combined treatment . The aims, indications and contraindications for the intubation are formulated . Bacteriologic and biochemical parameters of bowel content were studied . It was established that the quantity of enterobacteria and unfermenting gram-negative bacteria was increased in intestinal paresis, the alkaline phosphatase, amylase, bilirubin, transaminase, a potassium content were increased as well . For the tube to function from the first hours after its introduction it should be periodically properly washed with sodium hypochlorite in concentration 300 mg/l. Mol Plant Microbe Interact, 1999 Jun, 12(6), 499 - 507 Mutation in a gene required for lipopolysaccharide and enterobacterial common antigen biosynthesis affects virulence in the plant pathogen Erwinia carotovora subsp . atroseptica; Toth IK et al.; Spontaneous bacteriophage-resistant mutants of the phytopathogen Erwinia carotovora subsp . atroseptica (Eca) SCRI1043 were isolated and, out of 40, two were found to exhibit reduced virulence in planta . One of these mutants, A5/22, showed multiple cell surface defects including alterations in synthesis of outer membrane proteins, lipopolysaccharide (LPS), enterobacterial common antigen (ECA), and flagella . Mutant A5/22 also showed reduced synthesis of the exoenzymes pectate lyase (Pel) and cellulase (Cel), major virulence factors for this pathogen . Genetic analysis revealed the pronounced pleiotropic mutant phenotype to be due to a defect in a single gene (rffG) that, in Escherichia coli, is involved in the production of ECA . We also show that while other enteric bacteria possess duplicate homologues of this gene dedicated separately to synthesis of LPS and ECA, Eca has a single gene. J Microbiol Methods, 1999 May, 36(1-2), 129 - 38 Microbiological study of the dripping waters in Altamira cave (Santillana del Mar, Spain); Laiz L et al.; The culturable microbial populations in dripping waters from Altamira cave were studied and compared with those of the ceiling rock . Water communities have low proportions of gram-positive bacteria, and are mainly composed of gram-negative rods and cocci (Enterobacteriaceae and Vibrionaceae), while those of ceiling rocks are mainly Streptomyces spp . The community differences are probably related to environmental cave conditions: high humidity, relatively low and stable temperature, water pH close to neutrality and nature of the organic matter . All these factors seem to favor colonization and long-term growth of actinomycetes over other heterotrophic bacteria on ceiling rocks. Drugs, 1999 May, 57(5), 743 - 50 Practical recommendations for the drug treatment of bacterial infections of the male genital tract including urethritis, epididymitis and prostatitis; Joly-Guillou ML et al.; Bacterial infections of the male genital tract in young men (<35 years old) are primarily caused by sexually transmissible bacteria like Chlamydia trachomatis, Neisseria gonorrhoeae but also Mycoplasma or Haemophilus spp . In men aged over 35 years, Enterobacteriaceae are more frequently involved in urethritis, epididymitis and prostatitis . The traditional treatments suggested like tetracyclines or erythromycin are less effective since bacterial resistance is increasingly frequent, particularly in N . gonorrhoeae . Moreover, patient compliance with these drug treatments are frequently not well observed . New therapies including short term therapy with fluoroquinolones or azalides (e.g . azithromycin) are very effective and easy to use and thus eliminate any problem of compliance . However, we have to be vigilant for the emergence of resistant strains to these agents. Acta Chir Belg, 1999 Apr, 99(2), 85 - 6 Rupture of the spleen associated with Enterobacter cloacae; Peiper M et al.; A 58-year-old male, with abdominal pain but no signs of sepsis, was admitted as a medical emergency . During hospitalization, spontaneous splenic rupture was diagnosed and splenectomy successfully performed . A smear revealed presence of Enterobacter cloacae on the splenic surface; histopathology demonstrated granulocytous infiltration of the spleen. J Antimicrob Chemother, 1999 Apr, 43(4), 497 - 501 Efficacy of beta-lactam and inhibitor combinations in a diffusion chamber model in rabbits; Georgopoulos A et al.; Using a diffusion chamber in rabbits, we evaluated therapy with the combination of ceftriaxone plus the beta-lactamase inhibitor tazobactam in comparison with ceftriaxone alone . One sensitive and one resistant strain of Escherichia coli, Enterobacter cloacae and Klebsiella pneumoniae were inoculated into one of the six diffusion chambers, implanted in the same animal . In order to simulate pharmacokinetics in humans, both substances were administered in decreasing doses . Ceftriaxone was given 0, 2, 4 and 6 h after infection in dosages of 45, 35, 25 and 15 mg/kg of body weight, while tazobactam was administered either in one dose at 0 h, or divided into two doses at 0 and 1 h or 0 and 4 h, or divided into three doses at 0, 1 and 4 h after infection . The ratio of ceftriaxone:tazobactam was fixed at 8:1 . Ceftriaxone, in combination with tazobactam, given in one dose immediately after infection showed a significant reduction in bacterial count . All other combinations of ceftriaxone and tazobactam did not differ from ceftriaxone in monotherapy . Co-administration of the beta-lactamase inhibitor tazobactam significantly enhanced the activity of ceftriaxone against all three tested species. Appl Environ Microbiol, 1999 Jun, 65(6), 2513 - 9 Role of pfkA and general carbohydrate catabolism in seed colonization by Enterobacter cloacae; Roberts DP et al.; Enterobacter cloacae A-11 is a transposon mutant of strain 501R3 that was deficient in cucumber spermosphere colonization and in the utilization of certain carbohydrates (D . P . Roberts, C . J . Sheets, and J . S . Hartung, Can . J . Microbiol . 38:1128-1134, 1992) . In vitro growth of strain A-11 was reduced or deficient on most carbohydrates that supported growth of strain 501R3 but was unaffected on fructose, glycerol, and all amino acids and organic acids tested . Colonization by strain A-11 was significantly reduced (P </= 0.05) for cucumber and radish seeds compared to that of strain 501R3, but colonization of pea, soybean, sunflower, and sweet corn seeds was not reduced . Pea seeds released several orders of magnitude more total carbohydrates and amino acids than cucumber and radish seeds and approximately 4,000-fold more fructose . Fructose was the only carbohydrate detected in the seed exudates which supported wild-type levels of in vitro growth of strain A-11 . Soybean, sunflower, and sweet corn seeds also released significantly greater amounts of fructose and total carbohydrates and amino acids than cucumber or radish seeds . The exogenous addition of fructose to cucumber and radish seeds at quantities similar to the total quantity of carbohydrates released from pea seeds over 96 h increased the populations of strain A-11 to levels comparable to those of strain 501R3 in sterile sand . Molecular characterization of strain A-11 indicated that the mini-Tn5 kanamycin transposon was inserted in a region of the genome with significant homology to pfkA, which encodes phosphofructo kinase . A comparison of strain A-11 with Escherichia coli DF456, a known pfkA mutant, indicated that the nutritional loss phenotypes were identical . Furthermore, the pfkA homolog cloned from E . cloacae 501R3 complemented the nutritional loss phenotypes of both E . coli DF456 and E . cloacae A-11 and restored colonization by strain A-11 to near wild-type levels . These genetic and biochemical restoration experiments provide strong evidence that the quantities of reduced carbon sources found in seed exudates and the ability of microbes to use these compounds play important roles in the colonization of the spermosphere. Diagn Microbiol Infect Dis, 1999 May, 34(1), 65 - 72 Bacterial pathogens isolated from patients with skin and soft tissue infections: frequency of occurrence and antimicrobial susceptibility patterns from the SENTRY Antimicrobial Surveillance Program (United States and Canada, 1997) . SENTRY Study Group (North America); Doern GV et al.; As part of the SENTRY Antimicrobial Surveillance Program, 1562 bacterial isolates were recovered from hospitalized patients with skin and soft tissue infections (SSTIs) in 30 United States (U.S.) and 8 Canadian medical centers between October and December, 1997 . The overall rank order of recovery of the six most common pathogens was Staphylococcus aureus (42.6%) > Pseudomonas aeruginosa (11.3%) > Enterococcus spp . (8.1%) > Escherichia coli (7.2%) > Enterobacter spp . (5.2%) > beta-hemolytic streptocci (5.1%) . With one exception, essentially the same order was observed in both the U.S . and Canada . The single exception was the Enterococcus group, which were the third most common isolate in the U.S . (9.6%), but the seventh most common isolate in Canada (3.7) . Of note, 24.0% of S . aureus isolates were oxacillin resistant; vancomycin was uniformly active . Vancomycin resistance among Enterococcus spp . (16.5%) was observed only in the U.S . Several antimicrobial agents remained broadly active for SSTI isolates of P . aeruginosa, including meropenem, amikacin, tobramycin, and piperacillin with or without tazobactam . Imipenem resistance (MICs, > or = 8 micrograms/mL) was observed in 11.9% of isolates of P . aeruginosa and ceftazidime, and cefepime had equivalent activity (85.2% and 85.8% susceptible, respectively) . Numerous beta-lactams, aminoglycosides and fluoroquinolones were broadly active against E .