Biochemistry, 1992 Aug 4, 31(30), 6943 - 50 cDNAs and deduced amino acid sequences of subunits in the binding component of mouse bactericidal factor, Ra-reactive factor: similarity to mannose-binding proteins; Kuge S et al.; The complement-dependent bactericidal factor, Ra-reactive factor, binds specifically to Ra polysaccharide, which is common to some strains of Gram-negative enterobacteria, and its is a complex of proteins composed of a polysaccharide-binding component and a component that is presumably responsible for the complement activation . The former component consists of two different 28-kDa polypeptides, P28a and P28b . We determined the partial amino acid sequences of P28a and P28b, and the results indicated that these polypeptides were similar to two species of mannose-binding protein, MBP-C and MBP-A (alternative names, liver and serum mannan-binding proteins, respectively), which have been isolated from rat liver and/or serum {Drickamer, K., Dordal, M . S., & Reynolds, L . (1986) J . Biol . Chem . 261, 6878-6887; Oka, S., Itoh, N., Kawasaki, T., & Yamashina, I . (1987) J . Biochem . 101, 135-144} . Thus, we cloned the respective cDNAs, using as probes synthetic oligonucleotides for which the sequences had been deduced from the amino acid sequences of P28a and P28b and of rat MBP cDNAs . The primary structures of P28a and P28b deduced from the cloned cDNAs are homologous to one another . They have three domains, a short NH2-terminal domain, a collagen-like domain, and a domain homologous to regions of some carbohydrate-binding proteins, as has been reported for rat MBPs . Southern and Northern blotting analyses using these cDNAs indicated that the P28a and P28b polypeptides are the products of two unique mouse genes which are expressed in hepatic cells. J Pediatr, 1992 Aug, 121(2), 303 - 5 Use of ciprofloxacin in an infant with ventriculitis; Goepp JG et al.; Ciprofloxacin was used successfully in a neonate with ventriculitis caused by a multiply resistant strain of Enterobacter cloacae . Limited pharmacokinetic data indicated that adequate concentrations of drug could be attained in cerebrospinal fluid. J Med Microbiol, 1992 Aug, 37(2), 91 - 5 High prevalence of stably derepressed class-I beta-lactamase expression in multiresistant clinical isolates of Enterobacter cloacae from Greek hospitals; Tzelepi E et al.; Susceptibilities to cefotaxime (Ctx) and ceftazidime (Caz) were examined for 90 recent clinical isolates of Enterobacter cloacae from Greek hospitals . Most (68%) of the isolates were resistant to both drugs, and all were resistant to cefoxitin . beta-Lactamase activities against cephaloridine in crude extracts from Ctx-Caz-resistant isolates were high, irrespective of whether or not the cells were grown with cefoxitin as an inducer of the chromosomal beta-lactamase, indicating stable derepression of the gene for the enzyme . On the other hand, double disk antagonism tests showed that all the Ctx-Caz-sensitive isolates possessed inducible expression of this beta-lactamase . Iso-electric focusing revealed the presence of five forms of the chromosomal beta-lactamase, randomly distributed amongst the Ctx-Caz-resistant and -sensitive isolates . Plasmid-mediated beta-lactamases of TEM and PSE types also were found in many isolates . These data indicate that the extremely high prevalence of Ctx-Caz-resistant E . cloacae isolates in Greek hospitals is attributed to the dissemination of mutants which constitutively overproduce the class-I chromosomal beta-lactamase . Over 90% of these isolates exhibited cross-resistance to aminoglycosides, suggesting the accumulation of unrelated antibiotic resistance mechanisms. Mol Cell Probes, 1992 Aug, 6(4), 313 - 7 Enterobacterial tetracycline resistance in relation to plasmid incompatibility; Jones CS et al.; Sixty-eight well-characterized antibiotic resistance (R) plasmids belonging to 19 Incompatibility groups were screened with probes representing heterologous classes (A-E) of the enterobacterial tetracycline resistance (TcR) determinant . The Class B determinant was shown to be predominant in the IncF and IncH complexes and the IncC group . The Class A determinant was shown to be predominant in the IncP and IncM groups . There was no correlation between distribution of the class of TcR gene and the genus or the species of the host bacterial strain . The plasmids R714a (IncFI) and pHH1465 (IncC) contained TcR determinants which had no homology with any of these five probes. Pediatr Infect Dis J, 1992 Aug, 11(8), 623 - 30 Virulence properties of Enterobacteriaceae isolated from the small intestine of children with diarrhea; Penny ME et al.; Enterobacteriaceae isolated from the duodena of Peruvian children with persistent diarrhea (PD) have been examined for virulence factors and compared with Enterobacteriaceae isolated from children with acute diarrhea, those convalescent from PD and diarrhea-free controls . Escherichia coli were isolated from 42 of 186 (23%) of the aspirates . All 11 children with PD in whom multiple E . coli colonies were examined were colonized by a single serotype . DNA probes identified enterotoxigenic E . coli in 2 of 89 (2.2%) PD aspirates and 2 of 38 (5.3%) acute diarrhea aspirates and enteroaggregative E . coli in one PD and one control aspirate . Strains positive with the enteropathogenic E . coli adherence factor probe were identified from 2 of 89 (2.2%) patients with PD and 1 of 34 (2.9%) controls . A subset of 12 E . coli strains failed to show adhesion to human duodenal enterocytes although 5 of 9 showed sparse but polar attachment to ileal cells from a child with short bowel syndrome and PD . Three of 10 Enterobacteriaceae (two E . coli, one Klebsiella species) caused diarrhea in the reversible ileal tie adult rabbit model . Colonization with virulent Enterobactericeae did not explain the majority of episodes of PD . Examination of these duodenal bacteria in the rabbit model revealed some that caused diarrhea but were not recognized pathogens. Appl Environ Microbiol, 1992 Aug, 58(8), 2509 - 12 Nonspecific reactions of a commercial enzyme-linked immunosorbent assay kit (TECRA) for detection of staphylococcal enterotoxins in foods; Park CE et al.; A staphylococcal enterotoxin visual immunoassay kit (TECRA) has recently become commercially available . Since the kit is an enzyme-linked immunosorbent assay system equipped with polyvalent antisera against staphylococcal enterotoxin types A to E (SEA to SEE) and the test is simple and rapid to perform (4 h), it has been widely used for screening purposes . In this study, the sensitivity of the kit for detection of SEA, SEB, and SEC in ham, cheese, and mushrooms was similar to those of kits based on an enzyme immunoassay and reversed passive latex agglutination: 0.75 to 1.0 ng of SEA per ml, 0.5 to 0.75 ng of SEB per ml, and 1.0 to 1.25 ng of SEC per ml . However, the TECRA kit showed nonspecific reactions with food samples contaminated by microorganisms other than Staphylococcus aureus, such as Enterobacter agglomerans, Enterobacter cloacae, Proteus mirabilis, Pseudomonas aeruginosa, and Serratia marcescens . The substance contributing to the false-positive results differed from true staphylococcal enterotoxins in that it was (i) heat labile (completely inactivated by heating for 2 min at 100 degrees C, whereas true staphylococcal enterotoxins were inactivated by about 10% with this treatment), (ii) lower in molecular weight than staphylococcal enterotoxins, and (iii) not bound to a copper chelate Sepharose gel (all of the substance remained in the unbound wash fraction, whereas staphylococcal enterotoxins were quantitatively bound to the gel) . The problem of false-positive results with the TECRA kit could be resolved by heat treatment (2 min at 100 degrees C) or by cleanup procedures involving metal chelate affinity chromatography with copper chelate Sepharose for 4 h before use of the TECRA kit. Clin Nucl Med, 1992 Aug, 17(8), 627 - 9 Unsuspected meningitis diagnosed by In-111 labeled leukocytes . A case report; Spieth ME et al.; Clinically unsuspected bacterial meningitis was found in a patient with fever of unknown origin . Blood and urine cultures were negative for growth . Chest radiography and abdominal CT were negative for infection . Triple-phase bone imaging was performed to rule out osteomyelitis from a gunshot wound . A left posterior iliac crest hot spot may have represented osteomyelitis, but In-111 labeled leukocyte imaging instead disclosed unsuspected meningitis . The CSF culture after the imaging was positive for Enterobacter aerogenes. J Clin Pharmacol, 1992 Aug, 32(8), 692 - 7 Can fluoroquinolones be considered once-daily therapy? Neu HC. Fluoroquinolone antimicrobial agents inhibit most Enterobacteriaceae at extremely low concentrations, less than or equal to 0.5 microgram/mL . The half-lives of the agents range from 4 to 18 hours . Most of the available fluoroquinolones can be administered once daily to treat urinary tract and diarrheal infections . Newer agents with long half-lives that inhibit gram positive organisms at lower concentrations than the older fluoroquinolones, less than or equal to 1 microgram/mL, and have a long post-antibiotic effect have the potential to be used once daily as treatment of respiratory, skin-structure and selected bone infections as well . Careful clinical studies are needed to establish the efficacy of once daily use of fluoroquinolones, to determine that clinical efficacy is equivalent to multiple doses, and that once-daily dosing does not select more resistant bacteria . Single-dose therapy with quinolones would be an improvement in cost and patient compliance. Int J Food Microbiol, 1992 Aug, 16(4), 337 - 42 Antibacterial activity of essential oil components; Moleyar V et al.; Antibacterial activity of fifteen essential oil components towards food borne Staphylococcus sp., Micrococcus sp., Bacillus sp . and Enterobacter sp . was studied by an agar plate technique . Cinnamic aldehyde was the most active compound followed by citral, geraniol, eugenol and menthol . At 500 micrograms/ml, cinnamic aldehyde completely inhibited the bacterial growth for more than 30 days at 30 degrees C that was comparable to 200 micrograms/ml of butylated hydroxy anisole (BHA) . At lower temperatures, 25 and 20 degrees C, antibacterial activity of the five essential oil components increased . Addition of sodium chloride at 4% level (w/v) in the medium had no effect on the inhibitory activity of cinnamic aldehyde . In mixtures of cinnamic aldehyde and eugenol or BHA an additive effect was observed. Antimicrob Agents Chemother, 1992 Aug, 36(8), 1677 - 81 Resistance to cefotaxime and seven other beta-lactams in members of the family Enterobacteriaceae: a 3-year survey in France; Sirot DL et al.; During the second quarter each of 1988, 1989, and 1990, a French collaborative study group, including 12 university hospital laboratories, surveyed the resistance to beta-lactams of clinical isolates from hospitalized patients: consecutively, 10,641, 10,692, and 9,382 isolates were tested . The distribution of bacterial species over time was similar in each laboratory . The susceptibilities of microorganisms to amoxicillin, ticarcillin, cephalothin, cefoxitin, cefotaxime (CTX), ceftazidime (CAZ), aztreonam (ATM), and imipenem (IPM) were measured by the disk diffusion method in accordance with the recommendations of the Antibiogram Committee of the French Society for Microbiology . Five reference strains were included for quality control . Extended-spectrum beta-lactamases were detected by the synergistic effect of the combination of clavulanic acid-amoxicillin with CTX, CAZ, and ATM in the double-diffusion test . A synergistic effect with CTX, CAZ, and ATM was detected for 1.5% of all strains, mainly those of Klebsiella pneumoniae (13.3%) . For this species, the synergy test enabled the detection of roughly 50% of the resistant strains misclassified as susceptible on the basis of interpretative standards . Extended-spectrum beta-lactamases disseminated in 1990 in most enterobacterial species but at a low frequency . Important variations in the percentages of resistant strains were observed in terms of bacterial species, hospitals, and wards . However, when the total number of strains was considered, the percentages of resistance to newer beta-lactams remained low. Kansenshogaku Zasshi, 1992 Aug, 66(8), 1022 - 9 Changing patterns of blood culture isolates from patients with acute leukemia: a review of twenty years' experience; Funada H et al.; During the 20-year period, 1972-1991, 286 episodes of bacteremia occurred in 200 (45%) of 445 patients with acute leukemia in a hematology ward, giving an incidence of 482 episodes per 1,000 hospital admissions . The frequency of bacteremia was almost unchanged throughout the study period . The frequency of gram-negative bacilli decreased significantly, however, from 81% of all the isolates for the first half of the study period to 50% for the latter half . Despite the common use of ceftazidime and imipenem during the last 5-year period, Pseudomonas aeruginosa increased in frequency to be the most frequent organism . This was opposite to the decreased frequencies of Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae . The isolates of P . aeruginosa obtained during this period, all of which proved sensitive to ceftazidime and/or imipenem, were almost equally distributed among five serogroups, although a temporal preponderance of a limited number of serogroups was observed during the preceding 15-year period . On the other hand, the frequency of gram-positive cocci increased from 9% in the first decade to 35% in the latter decade . Staphylococcus epidermidis, Enterococcus species and, to a lesser extent, Staphylococcus aureus were ranked as major pathogens . Among the recent isolates of S . aureus, methicillin-resistant strains virtually replaced methicillin-sensitive ones . Therefore, until more effective means for control of P . aeruginosa bacteremia in particular become available, the occurrence of this infection will continue to limit the successful treatment of acute leukemia. J Antimicrob Chemother, 1992 Aug, 30(2), 119 - 27 Characterization of the plasmid mediated beta-lactamase BIL-1; Payne DJ et al.; A multi-resistant strain of Escherichia coli isolated from a patient from Pakistan was shown to possess a new plasmid-mediated beta-lactamase . This enzyme, designated BIL-1, conferred resistance to extended-spectrum cephalosporins such as cefotaxime and ceftazidime . However, unlike other plasmid-mediated beta-lactamases capable of conferring resistance to these drugs, the BIL-1 was not a member of the TEM or SHV group of plasmid-mediated beta-lactamases and it also conferred resistance to beta-lactam drugs in combination with beta-lactamase inhibitors (i.e . clavulanic acid) . The biochemical properties of the enzyme suggest that BIL-1 is related to the Richmond & Sykes Class I chromosomal beta-lactamases . Its inhibition properties by various beta-lactam drugs are similar to the inhibition properties of the chromosomally-encoded P99 enzyme of Enterobacter cloacae. J Bacteriol, 1992 Aug, 174(16), 5228 - 36 Nucleotide sequences of the genes regulating O-polysaccharide antigen chain length (rol) from Escherichia coli and Salmonella typhimurium: protein homology and functional complementation; Batchelor RA et al.; In this article, we report on the nucleotide sequences of the rol genes of Escherichia coli O75 and Salmonella typhimurium LT2 . The rol gene in E . coli was previously shown to encode a 36-kDa protein that regulates size distribution of the O-antigen moiety of lipopolysaccharide . The E . coli and S . typhimurium rol gene sequences consist of 978 and 984 nucleotides, respectively . The homology between the nucleotide sequences of these two genes was found to be 68.9% . Both the E . coli rol and S . typhimurium rol genes are transcribed counter to the histidine operon and code for deduced polypeptides of 325 and 327 amino acids, respectively . The S . typhimurium rol gene was previously identified to encode a protein of unknown function and to share a transcription termination region with his . The homology between these deduced polypeptide sequences was observed to be 72% . A complementation test was performed in which the S . typhimurium rol gene was placed in trans with an E . coli plasmid (pRAB3) which encodes the O75 rfb gene cluster and not rol . The protein expressed from the S . typhimurium rol gene was found to regulate the distribution of the O75 O polysaccharide on the lipopolysaccharide of the host strain, E . coli S phi 874 . The mechanism of Rol action may be independent of O antigen subunit structure, and its presence may be conserved in members of the family Enterobacteriaceae and other gram-negative bacilli that express O polysaccharides on their surface membrane. Zhonghua Min Guo Wei Sheng Wu Ji Mian Yi Xue Za Zhi, 1992 Aug, 25(3), 149 - 59 In vitro antibacterial activities of ticarcillin alone and ticarcillin plus clavulanic acid against beta-lactamase producing and non-producing microorganisms; Hsueh PR et al.; A total of 818 clinical bacterial isolates were tested for the production of beta-lactamase by rapid chromogenic cephalosporin method and for the susceptibility to ticarcillin alone and in combination with clavulanic acid (2 micrograms/mL) by agar dilution method . These included 83 strains of methicillin-sensitive Staphylococcus aureus (MSSA), 31 of methicillin-resistant S . aureus (MRSA), 49 of Neisseria gonorrhoeae, 58 of Haemophilus influenzae, 112 of Escherichia coli, 118 of Klebsiella pneumoniae, 58 of Proteus mirabilis, 30 of Proteus vulgaris, 60 of Serratia marcescens, 113 of Enterobacter cloacae, 60 of Pseudomonas aeruginosa and 46 of Bacteroides fragilis . The results revealed that 46.6% of P . mirabilis, 53.4% of H . influenzae, 57.1% of N . gonorrhoeae, 80% of P . vulgaris, 83.9% of MRSA, 85.6% of MSSA, 87.5% of E . coli, 91.7% of S . marcescens, 95.7% of B . fragilis, 98.2% of E . cloacae, and 100% of K . pneumoniae and P . aeruginosa strains produced beta-lactamase . In general, beta-lactamase nonproducers were more susceptible to ticarcillin than beta-lactamase producers . The ranges of minimum inhibitory concentrations (MICs) of ticarcillin for beta-lactamase nonproducers of MSSA, MRSA, H . influenzae, E . coli, P . vulgaris, S . marcescens, E . cloacae, B . fragilis and beta-lactamase producers of MSSA, H . influenzae strains were all within the in vitro susceptible range . The presence of clavulanic acid resulted in a significant enhancement of the antibacterial activity of ticarcillin against beta-lactamase producers of MRSA, N . gonorrhoeae, E . coli, K . pneumoniae, P . mirabilis, P . vulgaris and B . fragilis strains . Clavulanic acid had no synergistic activity for ticarcillin against S . marcescens, P . aeruginosa and E . cloacae. Eur J Clin Microbiol Infect Dis, 1992 Aug, 11(8), 728 - 32 Comparison of fixed concentration and fixed ratio options for testing susceptibility of gram-negative bacilli to piperacillin and piperacillin/tazobactam; Pfaller MA et al.; Piperacillin combined with tazobactam was tested at both a fixed ratio (8:1) and fixed tazobactam concentration (4 micrograms/ml) against 2,685 consecutively isolated gram-negative bacilli and 56 highly piperacillin-resistant isolates . Tazobactam significantly enhanced the spectrum of piperacillin activity . Overall, at a concentration of 16 micrograms/ml piperacillin alone inhibited 78.8% of the Enterobacteriaceae isolates compared to inhibition of 92.7% and 95.5% by the 8:1 ratio and fixed (4 micrograms/ml) tazobactam combinations, respectively . In MIC tests the two combination options performed comparably against both routine and highly piperacillin-resistant isolates . Synergistic inhibition was observed for comparable numbers of isolates with the two combination options, the most marked effect being seen in the more highly piperacillin-resistant isolates . Both testing options are supported by the available human pharmacokinetic data; however the 8:1 ratio of piperacillin to tazobactam may be preferable given that the clinical formulation contains the two compounds in an 8:1 ratio and this ratio is maintained in vivo. Diagn Microbiol Infect Dis, 1992 Aug, 15(6), 531 - 6 In vitro activity of CP-74667 compared with four other fluoroquinolones; Jones RN et al.; CP-74667 is a new, novel C-7 diazabicyclo-fluoroquinolone . Its spectrum of activity includes the Enterobacteriaceae, most nonenteric Gram-negative bacilli, and Gram-positive cocci . Particularly high activity was demonstrated against Xanthomonas maltophilia (MIC50, 1 microgram/ml), Staphylococcus spp . (MIC50s, 0.06-0.12 micrograms/ml) and enterococci (MIC50s, 0.5-4 micrograms/ml) . Several staphylococci resistant to ciprofloxacin had potentially susceptible range MICs for CP-74667, for example, less than or equal to 2 micrograms/ml . Fluoroquinolones with this C-7 modification appear promising and worthy of continued pharmaceutical investigation. Antimicrob Agents Chemother, 1992 Aug, 36(8), 1708 - 14 In vitro antibacterial activity of Q-35, a new fluoroquinolone; Ito T et al.; The in vitro activity of Q-35, an 8-methoxy fluoroquinolone, was compared with those of ofloxacin, ciprofloxacin, tosufloxacin, lomefloxacin, and sparfloxacin . The MICs of Q-35 for 90% of strains tested (MIC90s) of Staphylococcus aureus, methicillin-resistant S . aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, and Streptococcus pyogenes were 0.2, 6.25, 0.2, 0.39, and 0.39 micrograms/ml, respectively . The activity of Q-35 was 4- to 16-fold greater than those of ofloxacin, ciprofloxacin and lomefloxacin but equal to those of tosufloxacin and sparfloxacin against these organisms . For 82 ciprofloxacin-resistant staphylococci (MIC90 = 100 micrograms/ml), Q-35 was the most active of the new quinolones tested (MIC90 = 6.25 micrograms/ml) . The MIC90s of Q-35 against Escherichia coli, Enterobacter aerogenes, and Pseudomonas aeruginosa were 0.2, 0.78, and 12.5 micrograms/ml, respectively, and Q-35 was 2- to 16-fold less active than the other quinolones tested . Q-35 showed potent bactericidal activity and inhibited the supercoiling activity of DNA gyrase of S . aureus, E . coli, and P . aeruginosa. J Clin Microbiol, 1992 Aug, 30(8), 2054 - 7 Modified MacConkey medium which allows simple and reliable identification of Providencia stuartii; Thaller MC et al.; This work describes a modified MacConkey medium (MCP medium) enabling the simple identification of Providencia stuartii, an emerging nosocomial pathogen . A total of 813 strains, belonging to the families Enterobacteriaceae and Pseudomonadaceae, were tested on MCP medium; all P . stuartii strains were phosphatase positive, as were 97.5% of Morganella morganii strains, in contrast with all other tested organisms . A simple discriminating test, such as the ornithine or citrate test, allowed identification of strains of these species . We have also compared the reliabilities of P . stuartii identification by commercial kits (API 20E system) by using a standard MacConkey or MCP medium . Sixteen and three-tenths percent of P . stuartii strains were misidentified by using the former procedure, while with the latter all strains were correctly identified . Finally, the MCP medium was used over a 6-month period in our routine clinical laboratory . Of a total of 1,278 seeded urine samples from elderly patients, we isolated 103 P . stuartii strains which were all correctly identified by coupling MCP medium and the API 20E system . Seventeen and one-half percent of these strains were misidentified when the API 20E system was used in combination with standard MacConkey medium. Plant Mol Biol, 1992 Aug, 19(5), 759 - 70 Nucleotide sequence of diatom plasmids: identification of open reading frames with similarity to site-specific recombinases; Hildebrand M et al.; We have determined the nucleotide sequence of two small circular DNA plasmids, pCf1 and pCf2 {22}, from the marine diatom Cylindrotheca fusiformis . pCf1 is 4273 bp, and pCf2 is 4079 bp in size . In each plasmid, all of the major open reading frames (ORFs) are encoded on the same DNA strand . Two ORFs are similar, comparing the two plasmids . ORF218 (pCf1) and ORF217 (pCf2) share 80% amino acid identity and ORF482 (pCf1) and ORF484 (pCf2) share 54% amino acid identity . ORF218/217 shows significant similarity (28-31% amino acid identity) to the Tn3 class of resolvases . Resolvases are most commonly found in bacterial transposons . However, two other features found in the Tn3 class of transposon are missing in the plasmids; an ORF encoding a transposase and terminal inverted repeat sequences . This, and data mapping the portions of the plasmids that hybridize to genomic chloroplast DNA, suggest that the plasmids do not contain active transposons . By analogy with the R46 plasmid from Enterobacter {5, 6}, another potential role for the resolvases encoded by pCf1 and pCf2 is the conversion of multimeric forms of the plasmid to monomers . The similarity of ORF218/217 to resolvases documents the first identification of a potential coding function in an algal plasmid. FEBS Lett, 1992 Jul 20, 306(2-3), 108 - 12 A rapid-kinetic study of the class C beta-lactamase of Enterobacter cloacae 908R; Monnaie D et al.; The individual rate constants for acylation and deacylation (k2 and k3, respectively) of the class C beta-lactamase of Enterobacter cloacae 908R by ampicillin and carbenicillin have been determined . For several other beta-lactams, the value of k2 was too high to be determined and the k2/k3 ratio could be larger than 10,000 . Branched pathways were also shown to occur with several penicillins and cephalosporins. Nucleic Acids Res, 1992 Jul 11, 20(13), 3479 - 83 A highly conserved repeated DNA element located in the chromosome of Streptococcus pneumoniae; Martin B et al.; We report the discovery of a group of highly conserved DNA sequences located, in those cases studied, within intergenic regions of the chromosome of the Gram positive Streptococcus pneumoniae . The S . pneumoniae genome contains about 25 of these elements called BOX . From 5' to 3', BOX elements are composed of three subunits (boxA, boxB, and boxC) which are 59, 45 and 50 nucleotides long, respectively . BOX elements containing one, two and four copies of boxB have been observed; boxB alone was also detected in one instance . These elements are unrelated to the two most thoroughly documented families of repetitive DNA sequences present in the genomes of enterobacteria . BOX sequences have the potential to form stable stem-loop structures and one of these, at least, is transcribed . Most of these elements are located in the immediate vicinity of genes whose product has been implicated at some stage in the process of genetic transformation or in virulence of S . pneumoniae . This location raises the intriguing possibility that BOX sequences are regulatory elements shared by several coordinately controlled genes, including competence-specific and virulence-related genes. Diagn Microbiol Infect Dis, 1992 Jul, 15(5), 425 - 34 Ofloxacin, a new broad-spectrum fluoroquinolone . Results from a Multicenter, National Comparative Activity Surveillance Study . The Ofloxacin Surveillance Group; Jones RN et al.; Ofloxacin, a newer broad-spectrum fluoroquinolone, was evaluated against 6967 clinical isolates in a multicenter surveillance trial using a standardized disk diffusion method . Thirty-five geographically diverse laboratories contributed zone diameter results for two (ofloxacin and ciprofloxacin) to five (ofloxacin, ciprofloxacin, ampicillin, cefaclor, and cefixime) antimicrobial agents, depending on the site of infection . Ofloxacin was determined to have the widest spectrum of activity and potential empiric use (90.6%, range 87.1%-92.2%) for respiratory tract, urinary tract, and cutaneous infections . The spectrum was superior to ciprofloxacin (average 85.3% versus three sites), ampicillin (35.5%, respiratory tract), cefaclor (60.5%, respiratory tract), cefixime (60.9%, respiratory tract), and norfloxacin (87.3%, urinary tract) . Strains resistant to ofloxacin (35 isolates, 0.5%) were confirmed by reference laboratory tests and cross resistance was observed among several current and investigational fluoroquinolone agents . The species most often found to be fluoroquinolone resistant among the Enterobacteriaceae were Klebsiella pneumoniae, Serratia marcescens, and Providencia spp . Monitoring for increasing fluoroquinolone resistance should be considered as greater use of drugs in this class develops . By these cited statistics, ofloxacin appears to have a broad and balanced spectrum of potential use, particularly against Gram-positive pathogens. APMIS, 1992 Jul, 100(7), 623 - 8 Evaluation of a Salmonella-specific DNA probe by colony hybridization using non-isotopic and isotopic labeling; Aabo S et al.; A 2.3 kilobase (kb) Salmonella probe, JEO402-1, and two subfragments, F1214 (1.3 kb) and F1217 (0.8 kb), have been evaluated by colony hybridization using pure cultures of Salmonella serovars and non-salmonella bacteria . JEO402-1, and its subfragments, F1214 and F1217, hybridized to all of 156 different Salmonella serovars tested, while there was no reaction to 112 non-salmonella strains belonging to 19 genera and 37 species of Enterobacteriaceae . Together with previously published results, the JEO402-1 probe has now been shown to detect a total of 396 Salmonella strains belonging to 214 serovars of Salmonella subspecies I-VI . A total of 178 non-salmonella strains representing 23 genera and 51 species of Enterobacteriaceae have all tested negative with JEO402-1 . The hybridization results obtained using a digoxigenin-labeled probe were similar to those obtained with 35S isotopic labeling when complete colony lysis was ensured. Appl Environ Microbiol, 1992 Jul, 58(7), 2180 - 7 Use of repetitive (repetitive extragenic palindromic and enterobacterial repetitive intergeneric consensus) sequences and the polymerase chain reaction to fingerprint the genomes of Rhizobium meliloti isolates and other soil bacteria; de Bruijn FJ; The distribution of dispersed repetitive DNA (repetitive extragenic palindromic {REP} and enterobacterial repetitive intergenic consensus {ERIC}) sequences in the genomes of a number of gram-negative soil bacteria was examined by using conserved primers corresponding to REP and ERIC sequences and the polymerase chain reaction (PCR) . The patterns of the resulting PCR products were analyzed on agarose gels and found to be highly specific for each strain . The REP and ERIC PCR patterns of a series of Rhizobium meliloti isolates, previously ordered in a phylogenetic tree based on allelic variations at 14 enzyme loci (B . D . Eardly, L . A . Materon, N . H . Smith, D . A . Johnson, M . D . Rumbaugh, and R . K . Selander, Appl . Environ . Microbiol . 56:187-194), were determined . Isolates which had been postulated to be closely related by multilocus enzyme electrophoresis also revealed similar REP and ERIC PCR patterns, suggesting that the REP and ERIC PCR method is useful for the identification and classification of bacterial strains. Ann Rheum Dis, 1992 Jul, 51(7), 906 - 7 Infectious discitis caused by Enterobacter cloacae; Solans R et al.; The case is reported of a patient who developed a vertebral osteomyelitis caused by Enterobacter cloacae . The organism was isolated in cultures of blood and vertebral puncture biopsy samples . The patient was satisfactorily treated with trimethroprim and sulphamethoxazole . Enterobacter cloacae, a Gram negative organism, has been confirmed as the cause of bacteremia in patients with burns, urinary infections, in adults with pneumonia, and in children with joint infections . Spondylodiscitis caused by Enterobacter cloacae has not previously been described. J Dent Res, 1992 Jul, 71(7), 1374 - 81 The influence of denture-wearing and age on the oral microflora; Marsh PD et al.; The effects of denture-wearing and age on the prevalence of selected bacteria of dental significance and on the carriage of opportunistic pathogens in molar plaque and whole saliva were determined in 120 healthy subjects, 41 of whom wore partial dentures . The subjects were divided into four age groups: 20-39 years (group A), 40-59 years (group B), 60-79 years (group C), and greater than or equal to 80 years (group D) . The proportions, mean log10 viable counts, and isolation frequency of yeasts and lactobacilli in saliva and plaque were consistently higher in partial-denture wearers . The proportions of staphylococci and mutans streptococci were also raised in denture wearers, but these differences did not reach statistical significance . When the data were analyzed for age effects, both yeasts and lactobacilli were found to be increased in saliva with age, but statistically significant differences were generally found only between denture wearers in group D and subjects in the control group A . The isolation frequency of yeasts from plaque was also significantly higher in denture wearers of the oldest age group (D) compared with those in group A . A . viscosus predominated over A . naeslundii in the older age groups, regardless of the presence of dentures . Enterobacteria were isolated occasionally but only from the saliva of denture wearers in group D . Spirochetes and black-pigmented anaerobes were generally found in lower numbers in denture wearers . Collectively, the data show that components of the oral microflora in adults can be independently influenced by both age and the wearing of partial dentures. J Bacteriol, 1992 Jul, 174(14), 4583 - 93 Physical mapping of repetitive extragenic palindromic sequences in Escherichia coli and phylogenetic distribution among Escherichia coli strains and other enteric bacteria; Dimri GP et al.; Repetitive extragenic palindromic (REP) sequences are highly conserved inverted repeat sequences originally discovered in Escherichia coli and Salmonella typhimurium . We have physically mapped these sequences in the E . coli genome by using Southern hybridization of an ordered phage bank of E . coli (Y . Kohara, K . Akiyama, and K . Isono, Cell 50:495-508, 1987) with generic REP probes derived from the REP consensus sequence . The set of REP probe-hybridizing clones was correlated with a set of clones expected to contain REP sequences on the basis of computer searches . We also show that a generic REP probe can be used in Southern hybridization to analyze genomic DNA digested with restriction enzymes to determine genetic relatedness among natural isolates of E . coli . A search for these sequences in other members of the family Enterobacteriaceae shows a consistent correlation between both the number of occurrences and the hybridization strength and genealogical relationship. Infect Immun, 1992 Jul, 60(7), 2741 - 7 Characterization of the Shigella serotype D (S . sonnei) O polysaccharide and the enterobacterial R1 lipopolysaccharide core by use of mouse monoclonal antibodies; Viret JF et al.; In the course of developing a live vaccine, we generated three murine monoclonal antibodies (MAb) specific for Shigella sonnei . The specificities of these MAb were determined by enzyme-linked immunosorbent assay and immunoblot analyses with whole cells or purified lipopolysaccharides (LPSs) as antigens . Two of them are specific for the Shigella serotype D O-polysaccharide determinant, whereas one specifically binds to the core hexose region of R1-type LPSs . With these MAb, it was possible to analyze clinical isolates and a hybrid Salmonella typhi strain for their expression of the corresponding LPS moieties . In addition to their use in the screening of candidate vaccine strains, the new MAb provide a powerful tool for epidemiological and phylogenetic studies of natural enterobacterial populations. Vet Microbiol, 1992 Jul, 32(1), 75 - 80 The bactericidal effect of N-acetyl-beta-D-glucosaminidase on bacteria; Hussain AM et al.; The bactericidal activity of N-acetyl-beta-D-glucosaminidase (NAGase) on some of the potential bacterial pathogens of the cow was determined . NAGase treatment significantly decreased the mean log10 number of Actinomyces pyogenes (P less than 0.01) and Staphylococcus aureus (P less than 0.05) after 2 and 4 hours of incubation at 37 degrees C . Similarly NAGase treatment significantly (P less than 0.05) reduced the mean log10 number of Streptococcus agalactiae and Pseudomonas aeruginosa after 4 hours incubation at 37 degrees C . NAGase did not reduce the numbers of Escherichia coli or Enterobacter aerogenes after either 2 or 4 hours incubation . Since NAGase and presumably other lysosomal enzymes are free on normal mucosal surfaces such as the uterus it is suggested that this direct bactericidal activity may be an important component of the normal defense mechanisms. Mol Microbiol, 1992 Jul, 6(14), 2009 - 17 Negative transcriptional control of iron transport in Erwinia chrysanthemi involves an iron-responsive two-factor system; Expert D et al.; Systemic virulence of the phytopathogen Erwinia chrysanthemi 3937 requires a functional iron assimilation system which, in this enterobacterium, is mediated by the siderophore chrysobactin and the outer membrane transport protein Fct . We investigated the regulation of this system by iron . No direct similarity with the Escherichia coli fur gene was found . Insertional mutagenesis allowed isolation of a regulatory mutant which expressed chrysobactin and two other high-affinity iron transport systems previously characterized in strain 3937, regardless of the iron level . RNA/DNA hybridization analysis established that regulation of chrysobactin by iron occurs at the transcriptional level . From a wild-type gene library, a recombinant cosmid able to restore normal regulation in the mutant strain was isolated . By generating a series of subclones and mini-Mulac insertions, we identified a regulatory locus (cbr) extending beyond c . 2.5kb which encodes two polypeptides, CbrA and CbrB, with molecular weights of 34,000 and 55,000 respectively . Functional analysis of the locus suggests that the cognate genes cbrA and cbrB are clustered within an operon . Their expression was studied through chromosomal lac gene fusions, in the presence of plasmid-borne wild-type constructions, under high- and low-iron conditions . In summary, the data show that in the presence of iron, cbr negatively regulates the chrysobactin biosynthetic and transport genes, while under conditions of depletion, cbr is subject to negative autogeneous regulation. Mol Microbiol, 1992 Jul, 6(14), 1933 - 41 Evasion of type I and type II DNA restriction systems by IncI1 plasmid CoIIb-P9 during transfer by bacterial conjugation; Read TD et al.; Transmission of unmodified plasmid CoIIb-P9 by bacterial conjugation is markedly resistant to restriction compared with transfer by transformation . One process allowing evasion of type I and II restriction systems involves conjugative transfer of multiple copies of the plasmid . A more specialized evasion mechanism requires the Ard (alleviation of restriction of DNA) system encoded by CoIIb . The ard gene is transferred early in conjugation and specifically alleviates DNA restriction by all known families of type I enzyme, including EcoK . CoIIb has no effect on EcoK modification but this activity is impaired by multicopy recombinant plasmids supporting overexpression of ard . Genetic evidence shows that Ard protects CoIIb from EcoK restriction following conjugative transfer and that this protection requires expression of the gene on the immigrant plasmid . It is proposed that carriage of ard facilitates transfer of CoIIb between its natural enterobacterial hosts and that the route of DNA entry is important to the restriction-evasion mechanism. J Heart Lung Transplant, 1992 Jul-Aug, 11(4 Pt 1), 803 - 10; discussion 811 Successful use of the total artificial heart as a bridge to transplantation with no mediastinitis; Lonchyna VA et al.; High rates of infection, especially mediastinitis, have been reported with the use of the total artificial heart (TAH), thereby limiting its usefulness . We have used the TAH as a bridge to transplantation with only minor infectious complications and a zero incidence of mediastinitis . Between February 1988 and August 1990, the TAH was inserted at Loyola University Medical Center in 19 patients, ages 16 to 64 years (mean, 44 years) . Seventeen patients (89%) underwent transplantation within 1 to 34 days (mean, 9.8 days) . Of the patients who did not undergo transplantation, one was brain dead and the other died of bleeding diathesis . Early (30-day) deaths occurred in two patients (11.7%): acute rejection at 18 days and multiple cerebral infarcts at 14 days . Three late deaths (17.6%) occurred: one patient, cytomegalovirus and pneumocystis pneumonia at 4 months; one patient, bronchopneumonia and multisystem failure at 9 months; and one patient, chronic rejection at 14 months . Minor infectious complications during the TAH implantation included Enterobacter pneumonia treated with antibiotics and positive sputum cultures (Escherichia coli; Candida), with no clinical evidence of infection in two patients . No cases of mediastinitis occurred either while the TAH was implanted or after transplantation . All patients were on antibiotics while the device was in place . Conclusion: Our experience with the TAH shows this to be an excellent device for successful bridging of patients for heart transplantation . We have had minimal infectious complications and none directly attributed to the use of this device . This device should continue to be used safely as a bridge to transplantation. J Antimicrob Chemother, 1992 Jul, 30 Suppl A, 39 - 44 Comparative in-vitro activity of RP 59500; Verbist L et al.; The in-vitro activity of RP 59500 was compared with that of other appropriate antibiotics against 131 staphylococci, 97 streptococci, 20 enterococci, 68 Neisseria spp., 68 Haemophilus influenzae, 21 Moraxella catarrhalis and 250 Gram-negative bacilli . RP 59500 was more active than oxacillin, vancomycin and erythromycin against staphylococci (MIC 0.03-4 mg/L) . RP 59500 inhibited streptococci between 0.03-1 mg/L and enterococci between 1-8 mg/L, but was less active than ampicillin and erythromycin . However, its activity remained unchanged against strains with acquired resistance to ampicillin, erythromycin and oxacillin . It was as active as ampicillin against Neisseria spp., but less active against H . influenzae and M . catarrhalis . All enterobacteria and non-fermenters were resistant to RP 59500. Eur J Clin Microbiol Infect Dis, 1992 Jul, 11(7), 610 - 6 Evaluation of a new commercial system for the identification of Enterobacteriaceae and non-fermentative bacteria; Geiss HK et al.; The performance of a new commercial semi-automatic system (Cobas Micro, Becton Dickinson) for identification of gram-negative fermentative and non-fermentative bacilli was evaluated using strains of clinical origin belonging to 48 different species . Two groups of strains were tested: 510 strains using a long incubation period (21 hours) and 158 strains using a short incubation period (5 hours) . The correct identification rate without additional tests was 95.5% and 94.3% for the tests using a long and short incubation period respectively . The findings suggest that the system is highly accurate in the identification of most clinically important gram-negative rods, but shows some shortcomings in the identification of non-fermentative bacteria . The system is easy to use, and with some changes in the database and the inclusion of gram-positive and anaerobic bacteria would offer a valuable alternative to currently available automatic identification systems. Int J Syst Bacteriol, 1992 Jul, 42(3), 412 - 21 Phylogenetic interrelationships of members of the genera Aeromonas and Plesiomonas as determined by 16S ribosomal DNA sequencing: lack of congruence with results of DNA-DNA hybridizations; Martinez-Murcia AJ et al.; The phylogenetic interrelationships of members of the genera Aeromonas and Plesiomonas were investigated by using small-subunit ribosomal DNA (rDNA) sequencing . Members of the genus Aeromonas formed a distinct line within the gamma subclass of the Proteobacteria . Plesiomonas shigelloides also clustered within the confines of the gamma subclass of the Proteobacteria but exhibited a closer association with members of the family Enterobacteriaceae than with members of the family Aeromonadaceae . Species of the genus Aeromonas exhibited very high levels of overall sequence similarity (ca . 98 to 100%) with each other . Several of the relationships derived from an analysis of the rDNA sequence data were in marked disagreement with the results of chromosomal DNA-DNA pairing experiments . Diagnostic rDNA signatures that have possible value for differentiating most Aeromonas species were discerned. Antimicrob Agents Chemother, 1992 Jul, 36(7), 1447 - 55 Characterization of the chromosomal aac(6')-Ic gene from Serratia marcescens; Shaw KJ et al.; The DNA sequence of the chromosomal aac(6')-Ic gene from Serratia marcescens, which had been previously cloned (H . M . Champion, P . M . Bennett, D . A . Lewis, and D . S . Reeves, J . Antimicrob . Chemother . 22:587-596, 1988) was determined . High-pressure liquid chromatographic analysis of extracts prepared from Escherichia coli carrying the chromosomal aac(6')-Ic gene on a plasmid confirmed the presence of 6'-N-acetyltransferase activity in this strain, which was suggested by the aminoglycoside resistance profile . DNA sequence analysis of the cloned 2,057-bp PstI fragment revealed several regions of homology to previously characterized sequences from GenBank, including the rpoD and tRNA-2 genes of E . coli . Subcloning experiments confirmed the coding sequence of the aac(6')-Ic gene to be at positions 1554 to 1992 . The predicted amino acid sequence of the AAC(6')-Ic protein suggested that it was the third member of a family of AAC(6') proteins which included a coding region identified between the aadB and aadA genes of Tn4000 and an AAC(6') protein encoded by pUO490, which was isolated from Enterobacter cloacae . Primer extension analysis suggested that the -35 region of the aac(6')-Ic promoter overlapped a large palindromic sequence which may be involved in the regulation of the aac(6')-Ic gene . Hybridization experiments utilizing a restriction fragment from the aac(6')-Ic gene showed that all S . marcescens organisms carried this gene whether or not the AAC(6')-I resistance profile was expressed . Organisms other than Serratia spp . did not hybridize to this probe. Clin Infect Dis, 1992 Jul, 15(1), 30 - 2 Molecular analysis provides evidence for the endogenous origin of bacteremia and meningitis due to Enterobacter cloacae in an infant; Lambert-Zechovsky N et al.; We analyzed the restriction fragment length polymorphism (RFLP) of total DNA and of ribosomal DNA regions (ribotyping) to document the occurrence of endogenous, systemic bacteremia and meningitis due to Enterobacter cloacae in a newborn . Five strains of E . cloacae were isolated from this newborn . Three of these strains were recovered from stool at counts of 10(8), 10(9), and 10(9) organisms/g of feces, respectively; one strain was isolated from blood; and one strain was isolated from cerebrospinal fluid . In addition, five epidemiologically unrelated strains of E . cloacae were studied for comparison . Our study clearly shows the genetic relatedness of the strains isolated sequentially from cultures of stool, blood, and cerebrospinal fluid . RFLP analysis of total DNA and ribotyping seem particularly well suited to the study of the epidemiology of nosocomial E . cloacae strains. Antimicrob Agents Chemother, 1992 Jul, 36(7), 1491 - 8 Antimicrobial activity of DU-6859, a new potent fluoroquinolone, against clinical isolates; Sato K et al.; DU-6859, (-)-7-{(7S)-amino-5-azaspiro(2,4)heptan-5-yl}-8-chloro-6- fluoro-1-{(1R,2R)-cis-2-fluoro-1-cyclopropyl}-1,4-dihydro-4-oxoquinol one-3- carboxylic acid, is a new fluoroquinolone with antibacterial activity which is significantly better than those of currently available quinolones . The MICs for 90% of methicillin-susceptible and -resistant Staphylococcus aureus and Staphylococcus epidermidis clinical isolates (MIC90s) were 0.1, 3.13, 0.1, and 0.39 microgram/ml, respectively . MIC50s of DU-6859 against quinolone-resistant, methicillin-resistant S . aureus were 8-, 32-, 64-, and 128-fold lower than those of tosufloxacin and sparfloxacin, ofloxacin and fleroxacin, ciprofloxacin, and lomefloxacin, respectively . DU-6859 inhibited the growth of all strains of Streptococcus pneumoniae and Streptococcus pyogenes at 0.1 and 0.2 microgram/ml, respectively, and was more active against enterococci than the other quinolones tested . Although the activity of DU-6859 against Pseudomonas aeruginosa was roughly comparable to that of ciprofloxacin at the MIC50 level, it was fourfold more active than ciprofloxacin at the MIC90 level . DU-6859 was also more active against other glucose-nonfermenting bacteria, Haemophilus influenzae, Moraxella catarrhalis, and Neisseria gonorrhoeae, than the other drugs tested . Strains of Bacteroides fragilis and Peptostreptococcus spp . were susceptible to DU-6859; MIC90s were 0.39 and 0.2 microgram/ml, respectively . DU-6859 generally showed activities twofold or greater than those of ciprofloxacin and the other drugs against almost all members of the family Enterobacteriaceae . The action of DU-6859 against the clinical isolates was bactericidal at concentrations near the MICs . DU-6859 activity was not affected by different media, pH, inoculum size, or human serum but was decreased in human urine. Antimicrob Agents Chemother, 1992 Jul, 36(7), 1456 - 9 Double-blind randomized study comparing the efficacies and safeties of a short (3-day) course of azithromycin and a 5-day course of amoxicillin in patients with acute exacerbations of chronic bronchitis; Mertens JC et al.; The efficacies and safeties of a three-dose regimen of azithromycin (500 mg once daily for 3 days) and a 15-dose regimen of amoxicillin (500 mg three times daily for 5 days) were compared in a double-blind manner in patients with an acute exacerbation of chronic bronchitis . A total of 92% of patients suffered a type 1 exacerbation . Treatment success, defined as cure or major improvement, was achieved in all patients in the azithromycin group by day 5, compared with 23 (92%) of 25 patients in the amoxicillin group . On day 12, these data were 24 of 25 (96%) in the azithromycin group and 20 of 25 (80%) in the amoxicillin group (results were not significantly different) . Several pathogens were isolated (MIC ranges {micrograms per milliliter} in parentheses): Haemophilus influenzae or Haemophilus parainfluenzae was isolated 23 times (azithromycin, less than or equal to 0.06 to 32; amoxicillin, 0.12 to 2); Streptococcus pneumoniae was isolated from 11 patients (azithromcyin, less than or equal to 0.06 greater than 256; amoxicillin, less than or equal to 0.06 to 0.25); Moraxella (Branhamella) catarrhalis was isolated from eight patients (azithromycin, less than or equal to 0.06; amoxicillin, less than or equal to 0.06 to 16); and other members of the family Enterobacteriaceae were isolated from eight patients . One patient treated with azithromycin had Legionella pneumophila pneumonia, and another in that group had a significant rise in titer of antibody against influenza A virus . One patient treated with amoxicillin also had a significant rise in titer of antibody against influenza A virus . Microbiological response rates were comparable . One patient who received azithromycin developed abnormal liver function . Two patients treated with amoxicillin developed abnormal liver functions, one developed exanthema, and one treatment was stopped because of nausea . It is concluded that a three-dose (3-day) regimen of azithromycin is as effective clinically and microbiologically as a 15-dose (5-day) regimen of amoxicillin in the treatment of acute exacerbations of chronic bronchitis. Infect Immun, 1992 Jul, 60(7), 2619 - 26 Lactoferrin-binding proteins in Shigella flexneri; Tigyi Z et al.; The ability of Shigella flexneri to interact with lactoferrin (Lf) was examined with a 125I-labeled protein-binding assay . The percent binding of human lactoferrin (HLf) and bovine lactoferrin (BLf) to 45 S . flexneri strains was 19 +/- 3 and 21 +/- 3 (mean +/- standard error of the mean), respectively . 125I-labeled HLf and BLf binding to strain M90T reached an equilibrium within 2 h . Unlabeled HLf and BLf displaced the 125I-HLf-bacteria interaction in a dose-dependent manner . The Lf-bacterium complex was uncoupled by KSCN or urea, but not by NaCl . The interaction was specific, and approximately 4,800 HLf binding sites (affinity constant {Ka}, 690 nM) or approximately 5,700 BLf binding sites (Ka, 104 nM) per cell were estimated in strain M90T by a Scatchard plot analysis . The native cell envelope (CE) and outer membrane (OM) did not reveal Lf-binding components in sodium dodecyl sulfate-polyacrylamide gel electrophoresis . However, after being boiled, the CE and OM preparations showed three distinct horseradish peroxidase-Lf reactive bands of about 39, 22, and 16 kDa . The 39-kDa component was also reactive to a monoclonal antibody specific for porin (PoI) proteins of members of the family Enterobacteriaceae . The Lf-binding protein pattern was similar with BLf or HLf, for Crb+ and Crb- strains . The protein-Lf complex was dissociable by KSCN or urea and was stable after treatment with NaCl . Variation (loss) in the O chain of lipopolysaccharide (LPS) markedly enhanced the Lf-binding capacity in the isogenic rough strain SFL1070-15 compared with its smooth parent strain, SFL1070 . These data establish that Lf binds to specific components in the bacterial OM; the heat-modifiable, anti-PoI-reactive, and LPS-associated properties suggested that the Lf-binding proteins are porins in S . flexneri. Biochemistry, 1992 Jun 30, 31(25), 5869 - 78 Mechanism of inhibition of the class C beta-lactamase of Enterobacter cloacae P99 by phosphonate monoesters; Rahil J et al.; The class C serine beta-lactamase of Enterobacter cloacae P99 was inhibited by a series of aryl methylphosphonate monoester monoanions . The effectiveness of these inhibitors was promoted by an acylamido substituent on the methyl group and a good leaving group at phosphorus . The former preference suggests that noncovalent interaction of these inhibitors with the enzyme resembles that of substrates, while the latter suggests that nucleophilic displacement at phosphorus occurs as part of the inhibition mechanism . The truth of the latter proposition was confirmed by observation of release of 1 equiv of phenol concomitant with inhibition and of the presence of an equivalent amount of 14C-label on the enzyme after inhibition by a 14C-labeled phosphonate . The hydrolytically inert nature of the enzyme-inhibitor adduct, and its 31P chemical shift, suggested that O-phosphonylation of the enzyme had occurred . Although, by analogy with substrates, one might expect that the hydroxyl of the active site serine residue would be covalently modified by these inhibitors, successive alkali and acid treatment of the enzyme-inhibitor adduct generated no pyruvate . Instead, 1 equiv of lysinoalanine was found . This product was rationalized to arise through intramolecular capture by an adjacent lysine amine group of the dehydroalanine residue produced by alkali treatment of an O-phosphonylated serine residue . One equivalent of lysinoalanine was also produced by alkali treatment of the enzyme that had been inhibited by 6 beta-bromopenicillanic acid, a mechanism-based inhibitor known to acylate the hydroxyl group of the active site serine residue . It is therefore likely that the aryl phosphonates phosphonylate this residue . These compounds should be useful as beta-lactamase active site titrants and as sources of fresh insight into the chemical properties of the active site . The significant mechanistic features of the inhibition, in particular its strong leaving group dependence and the distinctive ability of the beta-lactamase active site to stabilize a dianionic transition state containing a pentacoordinated phosphorus, are discussed with respect to the active site structure . The comparison with phosph(or/on)yl inhibitors of serine proteinases is made, and the mechanism-based features of inhibition of serine hydrolases by phosph(on)ates are noted. Experientia, 1992 Jun 15, 48(6), 600 - 3 Biotransformation, by Enterobacter agglomerans, of pyrimidine acyclonucleosides to acyclonucleotides; Rutkowski M et al.; The ability of Enterobacter agglomerans to transform naturally occurring nucleosides into nucleotides has been utilized to transform newly synthesized pyrimidine acyclonucleosides into the corresponding acyclonucleotides . Unselected bacteria were used as the source of nucleoside phosphotransferase, the phosphate group donor being 4-nitrophenyl phosphate in the presence of Zn2+ ions . Optimal reaction conditions are outlined. J Appl Bacteriol, 1992 Jun, 72(6), 490 - 2 A one-minute oxidase test to detect Vibrio strains isolated from cultures on thiosulphate-citrate-bile salts-sucrose (TCBS) medium; Vila J et al.; Vibrio cholerae is oxidase positive, a primary characteristic used to differentiate it from Enterobacteriaceae . But false negative oxidase test results have been obtained with colonies from thiosulphate-citrate-bile salts-sucrose (TCBS) agar medium . A rapid oxidase test procedure is described here . This takes 1 min, avoids false negative results and the necessity to grow the bacteria in a general-purpose medium . The bacteria may be recovered after the test and used for further investigations. J Clin Microbiol, 1992 Jun, 30(6), 1541 - 3 Evaluation of the autoSCAN-W/A system for rapid (2-hour) identification of members of the family Enterobacteriaceae; O'Hara CM et al.; We evaluated the ability of the Baxter autoSCAN-W/A System (MicroScan Division, Baxter Diagnostics, Inc., West Sacramento, Calif.) to use the rapid (2-h) gram-negative identification panel for accurate identification of members of the family Enterobacteriaceae . At 2 h, 353 of 467 (75.6%) strains in a challenge set of biochemically typical and atypical stock cultures were correctly identified to genus and species . Another 76 (16.3%) strains were correctly identified to genus and species after the performance of recommended additional biochemical testing . Thus, at 24 h, 91.9% of the 467 strains were correctly identified . Twenty-two strains (4.7%) were identified to the correct genus but the incorrect species, and 16 strains (3.4%) were misidentified . Of these 16 strains, 9 were incorrect at 2 h, and 7 were incorrect after the additional testing . Because the system is based on fluorogenic substrates, no conventional tests were readily available with which to compare aberrant reactions . These results suggest that the autoSCAN-W/A with its rapid gram-negative panels is acceptable for the identification of the Enterobacteriaceae in a clinical microbiology laboratory. J Chemother, 1992 Jun, 4(3), 131 - 44 Parameters characterizing the in vitro activity of cefixime, a new oral broad spectrum cephalosporin, against respiratory and urinary pathogens; Debbia EA et al.; The wide and potent in vitro activity of cefixime, a new oral broad spectrum cephalosporin, has been confirmed on a collection of respiratory and urinary pathogens recently isolated in Italy . The new cephem emerged as the most bactericidal of all the comparators tested against several fast as well as slowly-growing gram-negative species including Enterobacteria, Haemophilus and Moraxella, irrespective of their ability to synthetize beta-lactamases . Among the gram-positive species Streptococcus pyogenes and S . pneumoniae were effectively covered . Cefixime activity was not adversely influenced by several important variables such as pH (over the range from 5 to 8), inoculum size (from 10(5) to 10(8) CFU per ml) and the presence of 50% human serum or urine . Time-kill tests confirmed a pronounced bactericidal potency of the drug especially towards common respiratory pathogens (H . influenzae, M . catarrhalis, S . pneumoniae and S . pyogenes) . Killing of urinary strains was optimal at cefixime concentrations reached in urine since eradication, except for Proteus mirabilis, was enhanced with increasing levels of the drug . The absence of an untoward paradoxic effect on the rate of cefixime bactericidal action was confirmed by employing a dynamic bladder model simulating the pharmacokinetic parameters of the drug after a single 200 mg daily dosage . Interactions of cefixime with several other drugs that may be employed in combination therapy were generally prone to provide indifference and synergism while antagonism was never observed . Favorable interactions were also registered when cefixime acted with other antibiotics on partially resistant species such as Staphylococci and Pseudomonas . The new cephem seems to provide excellent opportunities for expanding oral cephalosporin therapy to a wide range of infections produced by susceptible pathogens in the adult and pediatric populations. J Diarrhoeal Dis Res, 1992 Jun, 10(2), 93 - 6 Conjugal transferability of multiple antibiotic resistance in three genera of Enterobacteriaceae in Nigeria; Adeleye IA; Ninety-eight enteric bacteria were isolated from stool samples of 3,000 diarrhoeal patients during 1988-1989 in Ibadan, Nigeria . The isolates were: 20 Salmonella, 28 Shigella and 50 Escherichia coli . S . typhi and S . Flexneri were most prevalent while serotypes 055, 026 and 0128 were most common among the E . coli . Eight resistance patterns to ampicillin (Ap), streptomycin (Sm), tetracycline (Tc) and chloramphenicol (Cm), the four commonly used drugs in this environment were observed in the isolates . Resistance to all four drugs was common in the Shigella isolates . Conjugation experiments showed that 92% of the isolates tested were able to transfer all or part of their resistance to the recipient E . coli . The Salmonella and Shigella isolates were more efficient in this respect as all the isolates tested (100%) transferred all or part of their resistance character . Ability of the latter two genera to transfer the Ap, Sm, Tc, Cm complete linkage might be enhanced by using more efficient recipient or by mobilisation . Control of antibiotic usage and improvement of personal hygiene were recommended to prevent the spread of drug resistance among the enteric pathogens. J Antibiot (Tokyo), 1992 Jun, 45(6), 922 - 31 RU 29 246, the active compound of the cephalosporin prodrug-ester HR 916 . III . Pharmacokinetic properties and antibacterial activity in vivo; Klesel N et al.; The pharmacokinetics of the broad spectrum cephem RU 29 246 and its prodrug-ester HR 916 B were investigated in mice, rats and dogs and compared to those of cefpodoxime proxetil, cefuroxime axetil and cefixime . HR 916 B is well absorbed following oral administration and efficiently converted to the antibacterially active form . In mice, mean peak blood levels of 31.1 micrograms/ml of the parent compound were recorded within 20 minutes after oral administration of a single dose equivalent to 40 mg/kg RU 29 246 . The bioavailability calculated on the basis of the areas under the concentration-time curves (AUC) and the urinary recoveries was about 90% . In rats, peak blood levels of 14.5 micrograms/ml were obtained 1 hour after an oral 20 mg/kg dose . The bioavailability was calculated as 70% . In dogs, 40% of an oral 10 mg/kg dose was recovered in the urine within 24 hours . Cmax was 15.9 micrograms/ml at 4.6 hours . Mean elimination half-lives of RU 29 246 were 0.35, 0.5 and 2.1 hours in mice, rats and dogs, respectively . After an oral HR 916 B dose equivalent to 50 mg/kg of RU 29 246, tissue concentrations at 0.5 hour ranged between 0.8 micrograms/g in brain and 95.7 micrograms/g in murine kidneys . These values of HR 916 B are similar to, or distinctly higher than, those of the reference compounds . Of the oral cephalosporins tested, HR 916 B had the most balanced antibacterial spectrum . With ED50s of between 0.9 and 11.5 mg/kg against staphylococci, its activity was similar to that of the additional reference compound cefaclor and higher than that of cefuroxime . Cefixime and cefpodoxime proxetil displayed low antistaphylococcal activity or were inactive . In septicemias with Enterobacteriaceae, cefixime and cefpodoxime proxetil were more potent than HR 916 B and cefaclor . Cefuroxime axetil was inactive against most of these infections . HR 916 B was also highly effective against murine lung infections caused by Klebsiella pneumoniae DT-S or Streptococcus pneumoniae 1147. Ther Drug Monit, 1992 Jun, 14(3), 220 - 5 Tissue concentrations of cefepime in acute cholecystitis patients; Okamoto MP et al.; Cefepime is a new broad-spectrum cephalosporin with activity against Staphylococcus, Streptococcus, Pseudomonas, and the Enterobacteriaceae . The purpose of this study was to measure cefepime concentrations in plasma, peritoneal fluid, bile fluid and appendix tissue in patients undergoing elective cholecystectomy . Patients were randomly assigned to receive either cefepime, 2 g intravenously in phosphate buffer (IVPB) q 12 h or gentamicin 1.5 mg/kg IVPB q 8 h plus mezlocillin 4 g IVPB q 6 h . During surgery, gall bladder tissue, plasma, peritoneal fluid, and bile fluid samples were obtained at approximately the same time . Thirty-three patients had data acceptable for analysis . Values are given as mean +/- standard deviation . The mean delta time (defined as the time between the administration of cefepime and the time the samples were obtained) was 8.58 +/- 3.53 h . The values for plasma, peritoneal fluid, bile fluid, and gall bladder tissue concentrations were 7.63 +/- 14.17 micrograms/ml, 5.66 +/- 6.80 micrograms/ml, 15.51 +/- 16.94 micrograms/ml, and 5.36 +/- 6.57 micrograms/gm, respectively . The peritoneal fluid/plasma ratio was 2.10 +/- 2.33, the bile fluid/plasma ratio was 14.44 +/- 31.99, and the gall bladder tissue/plasma ratio was 1.44 +/- 1.82 . There was a significant correlation between peritoneal fluid and plasma concentration (r = 0.91, p less than 0.0005), and gall bladder tissue and plasma concentration (r = 0.90, p less than 0.0005) . There was no correlation between bile fluid and plasma cefepime concentrations . The minimum inhibitory concentration (MIC) data from previous in vitro studies indicate that cefepime concentrations achieved in this patient population would be adequate against typical biliary tract pathogens.(ABSTRACT TRUNCATED AT 250 WORDS) J Hosp Infect, 1992 Jun, 21(2), 95 - 101 Rapid genotyping shows the absence of cross-contamination in Enterobacter cloacae nosocomial infections; Bingen E et al.; Restriction fragment length polymorphism analysis (RFLP) of total DNA and rDNA regions was used for the epidemiological evaluation of 10 Enterobacter cloacae nosocomial isolates obtained from nine patients in our hospital . Five of these patients were hospitalized during overlapping periods, thus raising the question of cross-contamination . A single biochemical pattern and antibiotic susceptibility profile was observed for all isolates but one . In contrast, based on the results of total DNA and rDNA RFLP patterns, the genetic unrelatedness of the isolates was clearly shown, thus excluding a common source of contamination or patient-to-patient transfer. Antimicrob Agents Chemother, 1992 Jun, 36(6), 1310 - 5 In vitro activity of OPC-17116; Neu HC et al.; The in vitro activity of OPC-17116, a new C-5 methyl fluoroquinolone, was compared with the activities of other fluoroquinolones . OPC-17116 inhibited 50% of the members of the family Enterobacteriaceae tested and 90% of Haemophilus influenzae, Neisseria species, and Moraxella catarrhalis isolates at less than or equal to 0.25 microgram/ml . At less than or equal to 2 micrograms/ml, 90% of the Enterobacteriaceae were inhibited, which was comparable to or better than the activities of fleroxacin, ofloxacin, and lomefloxacin but less than the activity of ciprofloxacin . OPC-17116 inhibited 90% of the staphylococci tested at less than or equal to 0.25 micrograms/ml, but it did not inhibit methicillin-resistant, ciprofloxacin-resistant Staphylococcus aureus or Staphylococcus epidermidis . Group A, B, C, F, and G streptococci and Streptococcus pneumoniae were inhibited by less than or equal to 0.5 microgram/ml, being four-fold more active than ciprofloxacin and ofloxacin . Tosufloxacin was the most active agent tested against gram-positive cocci . OPC-17116 inhibited Bacteroides fragilis at 4 micrograms/ml . There was a minimal effect of inoculum size on MIC, and the MBCs were within 1 dilution of the MICs . The activity of OPC-17116 was decreased at pH 6 and in the presence of high Mg2+ concentrations, but it was unaffected by human serum . OPC-17116 showed a postantibiotic effect against Pseudomonas aeruginosa and Staphylococcus aureus similar to the postantibiotic effects reported for other fluoroquinolones . The frequency of spontaneous single-step resistance was low (less than 10(-9)), but repeated passage of organisms in the presence of OPC-17116 resulted in the selection of resistant isolates. J Antimicrob Chemother, 1992 Jun, 29(6), 649 - 60 The in-vitro activity of two new quinolones: rufloxacin and MF 961; Wise R et al.; The in-vitro activity of two new quinolone antimicrobials, rufloxacin and MF 961, together with the desmethylated metabolite of rufloxacin (MF 922) were compared with other orally administered agents against 622 bacterial strains . Against Enterobacteriaceae and Pseudomonas aeruginosa rufloxacin was generally active (MIC90 1-8 mg/L) with the exception of Klebsiella and Serratia spp . (MIC90 32 mg/L and Enterobacter spp . (MIC90) 64 mg/L . The respiratory pathogens Haemophilus influenzae and Moraxella catarrhalis were susceptible to rufloxacin (MIC90 0.5 and 1 mg/L respectively) but Streptococcus pneumoniae was less susceptible (MIC90 32 mg/L) . Staphylococcus aureus were susceptible to rufloxacin (MIC90 2 mg/L) . The rufloxacin metabolite MF 922 was generally as active as its parent . MF 961 was usually two-fold more active than rufloxacin . All three compounds were four to 16 times less active than norfloxacin, but rufloxacin was as active or somewhat more active than norfloxacin against Staphylococcus spp . Any strains showing decreased susceptibility to other quinolones exhibited cross resistance to these new agents . The MBC of rufloxacin and MF 922 was within one dilution of the MIC and human serum had little effect upon the activity of both agents . The protein binding of rufloxacin and MF 922 at 1 and 10 mg/L were 55% and 63.8% and 30.3% and 32.6% respectively . The activity of rufloxacin against four strains of Chlamydia trachomatis and one strain of Chlamydia pneumoniae was determined . The MICs for C . trachomatis were 4-8 mg/L and 4 mg/L for C . pneumoniae. FEMS Microbiol Lett, 1992 Jun 1, 72(2), 189 - 93 Distribution of insertion sequence IS1 in multiple-antibiotic resistant clinical Enterobacteriaceae strains; Ramirez-Santos J et al.; The presence of insertion sequence IS1 in 70 multiple-antibiotic resistant clinical strains was determined . This 70-strain collection comprised 46 Escherichia coli, 18 Salmonella and 6 Shigella strains . The presence of IS1 was detected in the chromosome and plasmids of 73% and 63% of the strains, respectively, and 51% of the strains carried IS1 in both . The frequency of IS1 was higher in Salmonella than in E . coli and Shigella strains . A total of 31 strains carried large plasmids with IS1; 10 of these strains (32.3%) were able to transfer all or some of the antibiotic resistance markers to E . coli K12 or S . typhimurium recipient strains . Resistance markers of all clinical strains were maintained stably after several generations of growth . The presence of IS1 in a relatively high percentage of plasmids of multiple-antibiotic resistant clinical isolates, suggests a role for this sequence in the dissemination of genes which code for antibiotic resistance. J Bacteriol, 1992 Jun, 174(12), 3945 - 52 Identification of novel loci affecting entry of Salmonella enteritidis into eukaryotic cells; Stone BJ et al.; There are an estimated 2 million cases of salmonellosis in the United States every year . Unlike the incidence of many infectious diseases, the incidence of salmonellosis in the United States and other developed countries has been rising steadily over the past 30 years, and the disease now accounts for 10 to 15% of all cases of acute gastroenteritis in the United States . The infecting organism is ingested and must traverse the intestinal epithelium to reach its preferred site for multiplication, the reticuloendothelial system . Despite several recent studies, the genetic basis of the invasion process is poorly understood . An emerging theme from these studies is that wild-type Salmonella organisms probably have several chromosomal loci that are required for the most efficient level of invasion . In this study, we have identified and characterized 13 TnphoA insertion mutants of Salmonella enteritidis CDC5 that exhibit altered invasion phenotypes . The mutants were identified by screening a bank of TnphoA insertions in S . enteritidis CDC5str for their invasion phenotype in three tissue culture cell lines (HEp-2, CHO, and MDCK) . These 13 mutants were separated into six classes based on their invasive phenotypes in the tissue culture cell lines . Several mutants were defective for entry of some cell lines but not for others, while two mutants (SM6 and SM7) were defective for entry into all three tissue culture cell lines . This suggests that Salmonella spp . may express more than one invasion pathway . Southern analysis and chromosomal mapping indicated that as many as nine chromosomal loci may contribute to the invasion phenotype . It is becoming clear that the invasive phenotype of Salmonella spp . is multifactorial and more complex than that of some other invasive members of the family Enterobacteriaceae. Zhonghua Nei Ke Za Zhi, 1992 Jun, 31(6), 338 - 40, 380 {Nosocomial pneumonia: a report of 372 cases}; Hou SR et al.; Three hundred seventy-two cases of hospital-acquired pneumonia occurring during a 4-year period were reviewed . It was found that the annual incidence of the pneumonia was 1.44% which ranked first in the incidence of nosocomial infections at this institution . Most of the patients had suffered from primary severe underlying diseases with immunosuppression of different degrees . A variety of factors such as antibiotic and steroid therapy, operation, intensive care, endotracheal intubation, tracheostomy, chemotherapy and radiotherapy predisposed to the acquisition of this pneumonia . Most frequent etiologic agents for hospital-acquired pneumonia were Enterobacteriaceae, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans . The overall mortality rate was 25.3% . However, deaths associated with Pseudomonas aeruginosa and Staphylococcus aureus are particularly high, with rates of 70.6% and 66.7% respectively . The incidence, mortality, pathogenesis, diagnosis, treatment and prevention of the disorder were discussed briefly. Microb Releases, 1992 Jun, 1(1), 41 - 6 Direct recovery and molecular analysis of DNA and RNA from soil; Selenska S et al.; A simple method for the recovery of DNA and direct detection of nif and Tn5 sequences in soil has recently been presented by Selenska and Klingmuller . On the basis of that method we have developed a procedure for the recovery and separation of DNA and RNA from the same soil sample . A 550 bp sequence from the Kmr gene of Tn5 was identified by PCR amplifications in total DNA and RNA, isolated from soil inoculated with a nitrogen-fixing Enterobacter agglomerans 19-1-1, which carries this transposon . Hence, not only the presence of the Kmr gene of Tn5 but also its expression (mRNA synthesis) in the analyzed environmental samples was detected . The authenticity of the products of PCR amplifications of DNA and mRNA was confirmed by the PhotoGene hybridization technique. Appl Environ Microbiol, 1992 May, 58(5), 1524 - 9 Rapid detection of members of the family Enterobacteriaceae by a monoclonal antibody; Levasseur S et al.; Six monoclonal antibodies directed against enterobacteria were produced and characterized . The specificity of one of these antibodies (CX9/15; immunoglobulin G2a) was studied by indirect immunofluorescence against 259 enterobacterial strains and 125 other gram-negative bacteria . All of the enterobacteria were specifically recognized, the only exception being Erwinia chrysanthemi (one strain tested) . Bacteria not belonging to members of the family Enterobacteriaceae were not detected, except for Plesiomonas shigelloides (two strains tested), Aeromonas hydrophila (five strains tested), and Aeromonas sobria (one strain tested) . This recognition spectrum strongly suggested that CX9/15 recognized the enterobacterial common antigen . By sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot (immunoblot) experiments, the six antienterobacteria antibodies presented similar specificities; they all revealed only one band with an apparent molecular weight of about 20,000 from the crude extract of an enterobacterium . The six monoclonal antibodies, and especially CX9/15, can be used to develop new tests for rapid and specific detection of enterobacteria. J Appl Bacteriol, 1992 May, 72(5), 381 - 5 Conjugal transfer of R plasmids to and from Enterobacteriaceae isolated from sewage; Fernandez-Astorga A et al.; The potential of the transfer of natural plasmids between sewage strains has been studied . In vitro transfer was conducted at 37 degrees C in tryptone soya broth and sterile raw sewage as mating media . In situ transfer was carried out in sterile raw sewage within membrane diffusion chambers at 10.6 degrees C . When the recipient was a laboratory strain of Escherichia coli K-12, the in situ frequency values were significantly lower (P less than 0.001) than those obtained in vitro for the same mating pair . When the laboratory recipient was replaced with recipients from the same sewage source, frequency values decreased progressively from the optimum conditions to the most adverse . However, in situ frequency values were higher than those for the same donors mated with a laboratory recipient. J Heart Lung Transplant, 1992 May-Jun, 11(3 Pt 1), 545 - 9 Bacterial mediastinitis after heart transplantation; Baldwin RT et al.; Bacterial mediastinal abscess or mediastinitis developed in nine (2.5%) of 361 consecutive patients who underwent isolated heart transplantation at the Texas Heart Institute . All nine patients had at least one predisposing factor that may have contributed to the development of mediastinitis . These included insulin-dependent diabetes mellitus, repeat operation for postoperative mediastinal hemorrhage, Staphylococcus aureus pneumonitis, and cardiac allograft rejection in the early postoperative period (less than 30 days), necessitating steroid pulse therapy alone or in combination with murine-derived monoclonal antibody (OKT3) . In six of the nine patients, the diagnosis of mediastinitis was made on the basis of clinical findings (unstable sternum and incisional erythema, with or without gross purulence), and in the other three patients, diagnosis was confirmed by computed tomography of the chest . Culture data were unequivocal in all patients; S . aureus was the most frequent (five patients), followed by S . epidermidis (two patients), and Enterobacter cloacae (two patients) . Computed tomography-directed percutaneous drainage and systemic antibiotics were successful in treating two of three patients who had stable sternums with mediastinal abscess . In the remaining seven patients, sternal and mediastinal debridement with rewiring of the sternum was successfully applied . No patient required muscle or omental flap coverage, and no patient experienced a recurrence of mediastinitis during an average follow-up period of 35 months (range, 12 to 46 months). Arch Dis Child, 1992 May, 67(5), 595 - 9 HIV-1 infection and perinatal mortality in Zimbabwe; Aiken CG; As part of a survey of the causes of perinatal mortality at Mpilo Maternity Hospital, 220 neonatal deaths and the mothers of 221 stillbirths were tested for HIV-1 antibodies . The HIV positive rate in neonatal deaths was 23.6% (95% confidence interval (CI) 18.0 to 29.2%), significantly higher than 15.4% (95% CI 10.6 to 20.1%) in stillbirths . Perinatal deaths from congenital malformations, birth asphyxia, pregnancy induced hypertension, placental abruption, and oFther non-infectious causes had similar low HIV positive rates averaging 8.1% (95% CI 3.9 to 12.3%) . Deaths from septicaemia had a significantly greater rate of 39.3% (95% CI 27.0 to 51.6%) and the highest rate of 72.2% (95% CI 51.5 to 92.9%) was found in deaths from congenital infection other than syphilis, indicating that maternal HIV infection predisposes to neonatal septicaemia and congenital infection . Unexplained stillbirths also had a significantly greater rate of 22.4% (95% CI 10.7 to 34.1%), presumably because some died from unrecognised infection . The rate in deaths from congenital syphilis was 17.4% (95% CI 9.6 to 25.2%), indicating a significant but weak association between these two sexually transmitted diseases in Bulawayo . The rate in deaths from hyaline membrane disease was not significantly greater at 15.0% (95% CI 6.0 to 24.0%) . By predisposing to infection, maternal HIV infection was estimated to increase the stillbirth rate by 1.6 times and the neonatal mortality rate by 2.7 times . It predisposed equally to early and late onset neonatal septicaemia, but more to infection from streptococci and staphylococci than from Gram negative enterobacteria . HIV positive deaths from congenital infection had respiratory distress and usually intrauterine growth retardation, hepatosplenomegaly, and congenital pneumonia on lung histology. J Trauma, 1992 May, 32(5), 570 - 5 Prevention of infection in burns: preliminary experience with selective decontamination of the digestive tract in patients with extensive injuries; Mackie DP et al.; Evidence from studies of trauma patients suggests that selective decontamination of the digestive tract (SDD) might also be of value in preventing colonization and infection by enteric organisms in burn patients . In a retrospective study, 31 consecutive patients with burns of greater than 30% of total body surface area, admitted over a 2-year period, who were treated with an SDD regimen, were compared with a similar group of 33 consecutive patients admitted in the 2 years immediately preceding the introduction of SDD . Fewer SDD-treated patients developed wound colonization with Pseudomonas species (29% vs . 61%), or with Enterobacteriaceae (10% vs . 73%) . Similar reductions in colonization with gram-negative organisms were found in urine and gastric aspirates . There were fewer respiratory infections in the SDD group (6.5% vs . 27.3%), and only one patient developed septicemia, compared with eight in the control group (3.2% vs . 24.2%) . Fewer SDD-treated patients died (one death, compared with seven in the non-SDD group) . These results suggest that SDD may be of value in the management of patients with severe burn injuries, but further studies are required to test the validity of this conclusion. Urology, 1992 May, 39(5), 453 - 6 Multicenter open-label study of parenteral ofloxacin in treatment of pyelonephritis in adults; Cox CE et al.; The efficacy and safety of parenteral ofloxacin were evaluated in an open, multicenter study of hospitalized patients with pyelonephritis . The patients received ofloxacin 400 mg IV as an initial dose followed by ofloxacin 200 mg IV b.i.d . for a minimum of three days . The patients could then continue ofloxacin orally 200 mg b.i.d . for a total of seven to fourteen days . The most common pathogens isolated were Escherichia coli, Enterobacter cloacae, and Klebsiella pneumoniae . Microbiologic eradication was achieved in 65 of 66 evaluable patients (98%), and clinical cure or clinical improvement was noted in all patients . Of 82 patients evaluable for safety, 12 (15%) reported drug-related adverse events, the most frequent of which was pruritus or rash . None of the patients experienced drug-related central nervous system symptoms . Ofloxacin is well tolerated and highly effective in the treatment of pyelonephritis. J Bacteriol, 1992 May, 174(9), 3070 - 7 Isolation and characterization of kikA, a region on IncN group plasmids that determines killing of Klebsiella oxytoca; Hengen PN et al.; Transfer of the IncN group plasmid pCU1 from Escherichia coli to Klebsiella oxytoca by conjugation kills a large proportion (90 to 95%) of the recipients of plasmid DNA, whereas transfer to E . coli or even to the closely related Enterobacter aerogenes does not . Two regions, kikA and kikB, have been identified on pCU1 that contribute to the Kik (killing in klebsiellas) phenotype . We have localized the kikA region to 500 bp by deletion analysis and show by DNA-DNA hybridization that kikA is highly conserved among the plasmids of incompatibility group N . The expression in K . oxytoca of kikA under the control of the strong inducible E . coli tac promoter results in loss of cell viability . The nucleotide sequence showed two overlapping open reading frames (ORFs) within the kikA region . The first ORF codes for a putative polypeptide of 104 amino acids (ORF104) . The second ORF codes for a 70-amino-acid polypeptide (ORF70) . The properties of the putative protein encoded by ORF104 and gene fusions of kikA to alkaline phosphatase by using TnphoA suggest that killing may involve an association with the bacterial membrane; however, we could not rule out the possibility that ORF70 plays a role in the Kik phenotype. J Bacteriol, 1992 May, 174(9), 2993 - 3003 High-affinity iron uptake systems present in Erwinia carotovora subsp . carotovora include the hydroxamate siderophore aerobactin; Ishimaru CA et al.; The phytopathogenic bacterium Erwinia carotovora subsp . carotovora W3C105 produced the hydroxamate siderophore aerobactin under iron-limiting conditions . A survey of 22 diverse strains of E . carotovora revealed that strain W3C105 alone produced aerobactin . The ferric-aerobactin receptor of strain W3C105 was an 80-kDa protein, identified by immunoblots of Sarkosyl-soluble proteins obtained from E . carotovora cells grown in iron-depleted medium and probed with antiserum raised against the 74-kDa ferric-aerobactin receptor encoded by the pColV-K30 plasmid of Escherichia coli . Genes determining aerobactin biosynthesis and uptake were localized to an 11.3-kb EcoRI-HindIII chromosomal fragment of strain W3C105 . A 10-kb subclone of the fragment conferred on E . coli DH5 alpha both aerobactin biosynthesis and uptake, determined by cloacin DF13 sensitivity, the presence of the 80-kDa receptor protein, and iron-independent growth of E . coli clones . The aerobactin biosynthesis genes of E . carotovora W3C105 hybridized to those of the pColV-K30 plasmid of E . coli, but the restriction patterns of the aerobactin regions of E . coli and E . carotovora differed . Although the aerobactin region of enteric bacteria is commonly flanked by IS1-like sequences, IS1 sequences were not detected in the genomic DNA or the cloned aerobactin region of E . carotovora . E . coli DH5 alpha cells harboring cloned aerobactin biosynthesis genes from E . carotovora W3C105 produced greater quantities of aerobactin and the 80-kDa ferric-aerobactin receptor when grown in iron-limited than in iron-replete medium . Strain W3C105 grew on an iron-limited medium, whereas derivatives that lacked a functional aerobactin iron acquisition system did not grow on the medium . These results provide evidence for the occurrence and heterogeneity of aerobactin as a high-affinity iron uptake system of both clinical and phytopathogenic species of the Enterobacteriaceae . Although future studies may reveal a role for aerobactin in the virulence or ecology of strain W3C105, a functional aerobactin iron acquisition system is not necessary for the pathogenicity of E . carotovora. Gene, 1992 May 1, 114(1), 13 - 8 The Escherichia coli Mu/D108 phage ner homologue gene (nlp) is transcribed and evolutionarily conserved among the Enterobacteriaceae; Autexier C et al.; The Escherichia coli nlp gene is highly homologous to the regulatory ner genes of transposable coliphages, Mu and D108 . It was discovered, via its action when overexpressed, as a positive activator of mal gene expression in a cya- crp*1 strain . Chromosomal disruption of the nlp gene by insertion of a promoterless luxAB reporter gene revealed that nlp is nonessential for E . coli viability . Light measurements from the resulting nlp::luxAB transcriptional fusion, plus RNA dot blot analysis, suggest that nlp is transcribed . Southern-blot analyses of DNAs from several bacterial species were performed and indicate that nlp is evolutionarily conserved, but only among closely related Enterobacteriaceae. Pathol Biol (Paris), 1992 May, 40(5), 551 - 5 {Detection of extended-spectrum beta-lactamases by the rapid ATB E technique . Value of the API V2.1.1 expert system}; Hirtz P et al.; Twenty-two extended-spectrum betalactamase-producing strains of enterobacteriaceae recovered in the authors' hospital were tested using the Rapid ATB E coupled with the API V2.1.1 . expert system . The expert system detected 90.9% of ESBL-producing strains . Two strains producing a SHV2 and a CTX1, respectively, escaped detection by the expert system despite concomitant resistance to aminoglycosides. J Med Assoc Thai, 1992 May, 75(5), 287 - 92 In vitro antimicrobial activity of cefodizime, a third generation cephalosporin; Pruksachatvuthi S et al.; Cefodizime is one of the new broad-spectrum cephalosporins . It is an aminothiazolyl iminomethoxy cephalosporin which is metabolically stable and has a prolonged serum half life . Cefodizime was primarily active against gram-negative bacilli and at the concentration of 0.5 mg/L, it inhibited 90 per cent of Enterobacteriaceae . P . mirabilis was the most susceptible species tested (MIC90 of 0.02 mg/L) . E.coli, K.pneumoniae, Salmonella spp., Shigella spp . and M . morganii were also very sensitive to cefodizime, with the MIC90 of 0.25-0.5 mg/L . Cefodizime, however, was not active against most gram-negative bacilli possessing Type I beta-lactamases of Richmond and Sykes, namely, Enterobacter spp., P . aeruginosa and A . anitratus (MIC90 of > 128 mg/L) . Among gram-positive bacteria, only S.pyogenes was highly susceptible (MIC90 of 0.05 mg/L), while S . aureus (methicillin-sensitive) was moderately susceptible and Enterococcus spp . was resistant . Cefodizime appeared to be bactericidal and was not affected by serum . High inoculum (10(7) cfu/ml) of K.pneumoniae and Enterobacter spp . resulted in increase of the MIC of cefodizime . This study shows that local bacterial isolates in a university hospital in Bangkok, Thailand were not different in susceptibility pattern from those reported in developed countries . The in vitro activity of cefodizime as a third generation cephalosporin, with its good pharmacokinetic property, and the property of the agent as a biological response modifier, should prove that this is a promising new agent in treating serious infections especially in immunosuppressed hosts. Int J Food Microbiol, 1992 May, 16(1), 79 - 85 Antibiotic and disinfectant susceptibility in Enterobacteriaceae isolated from minced meat; Stecchini ML et al.; The resistance of Enterobacteriaceae isolated from minced meat to antibiotics and to an amphoteric surfactant, was examined . Despite the wide range of antibiotic resistance occurring in the strains tested, resistance to the disinfectant was not observed. J Hosp Infect, 1992 May, 21(1), 29 - 37 Microbiology of postoperative wound infection: a prospective study of 1770 wounds; Twum-Danso K et al.; A prospective study of postoperative wound infection was carried out over a 12-month period . Intra-operative swabs from the patients' anterior nares, the opened viscus and parietes were cultured using standard bacteriological techniques . Of the 1770 wounds studied, 167 (9.4%) became infected . Wound infection rates, according to clinical wound types, were clean 5.9%, clean-contaminated 10.7%, contaminated 24.3% and dirty 52.9% . The figures according to microbiological wound types were clean 4.7%, and potentially, lightly and heavily contaminated 15.3%, 22.1% and 30.2% respectively . The commonest causative organisms were Staphylococcus aureus 23.7%, Escherichia coli 16.9%, Staphylococcus epidermidis 13.5% and Pseudomonas aeruginosa 13.0% . When isolated intra-operatively, Enterobacter spp., Proteus spp., Klebsiella spp . and P . aeruginosa appeared to have a high probability of causing postoperative wound infection, but the intra-operative isolation of Bacteroides sp . was a poor predictor of subsequent wound infection. J Antimicrob Chemother, 1992 May, 29(5), 519 - 27 In-vitro activity of PD 131628, a new quinolone antimicrobial agent; Cooper MA et al.; The in-vitro activity of PD 131628, the active metabolite of the prodrug PD 131112, was compared with that of ciprofloxacin and members of other groups of antimicrobial agents against 701 recent clinical isolates and strains with known mechanisms of resistance . The MIC90s of PD 131628 against the Enterobacteriaceae were between 0.008 and 0.5 mg/L; PD 131628 was one- to four-fold more active than ciprofloxacin against these strains and was four-fold more active than ciprofloxacin against Pseudomonas aeruginosa . Against the Gram-positive species tested, PD 131628 was two- to four-fold more active than ciprofloxacin, inhibiting all strains of Staphylococcus aureus and Streptococcus pneumoniae with 0.5 mg/L or less . PD 131628 was very active against Neisseria spp., Haemophilus influenzae and Moraxella catarrhalis, with MIC90s ranging from 0.004 to 0.008 mg/L . Organisms with decreased susceptibility to other quinolones had decreased susceptibility to PD 131628, but there was no cross-resistance between this class of antimicrobial and other classes . The protein binding of PD 131628 was at most 25% across a broad range of concentrations . The addition of 70% human serum had little effect on the MICs, but caused a two- to eight-fold increase in MBCs. FEBS Lett, 1992 Apr 27, 301(3), 271 - 6 The UDP-N-acetylglucosamine 1-carboxyvinyl-transferase of Enterobacter cloacae . Molecular cloning, sequencing of the gene and overexpression of the enzyme; Wanke C et al.; The UDP-N-acetylglucosamine 1-carboxyvinyltransferase (enolpyruvyltransferase, EC 2.5.1.7) which catalyses the first committed step in the biosynthesis of the bacterial cell-wall peptidoglycan was purified to near homogeneity from Enterobacter cloacae and the NH2-terminal amino-acid sequence determined . Using the polymerase chain reaction a 53-bp DNA fragment was synthesized; this fragment encodes the NH2-terminal sequence of the enzyme . A clone was then isolated which contained an open reading frame of 1257 bp coding for a protein of 419 amino acids . This protein was overexpressed 100-fold in transformed Escherichia coli cells and shown to possess the enolpyruvyltransferase activity . The overall amino-acid sequence of the enolpyruvyltransferase is significantly similar to that of the 5-enolpyruvylshikimate 3-phosphate synthase, the only other enzyme known to catalyse the transfer of the enolpyruvate moiety of phosphoenolpyruvate to a substrate. J Biol Chem, 1992 Apr 25, 267(12), 8275 - 80 Glutamyl-tRNA reductase from Escherichia coli and Synechocystis 6803 . Gene structure and expression; Verkamp E et al.; In the cyanobacterium Synechocystis sp . PCC 6803 and in the enterobacterium Escherichia coli delta-amino-levulinic acid (ALA) is formed from glutamyl-tRNA by the sequential action of two enzymes, glutamyl-tRNA reductase (GluTR) and glutamate-1-semialdehyde aminotransferase . E . coli has two GluTR proteins with sizes of 45 kDa (GluTR45) and 85 kDa (GluTR85) (Jahn, D., Michelsen, U., and Soll, D . (1991) J . Biol . Chem . 266, 2542-2548) . The hemA gene, isolated from E . coli and several other eubacteria, has been proposed to encode a structural component of GluTR . Because of the inability to overexpress this gene in E . coli, we demonstrate directly GluTR function for the E . coli hemA gene product by its expression and functional analysis in yeast, which does not form ALA from Glu-tRNA . Gel filtration experiments demonstrated definitively that the yeast-expressed HemA protein corresponded to GluTR45 . Furthermore, analysis of GluTR activity in an E . coli strain with a disrupted hemA gene displayed GluTR85, but not GluTR45 activity . The hemA gene from Synechocystis 6803 was cloned by functional complementation in E . coli . DNA sequence analysis revealed an open reading frame capable of encoding a 427-amino acid polypeptide (molecular mass of 47,525 Da) . The Synechocystis 6803 amino acid sequence shows significant similarity upon alignment with HemA sequences from E . coli, Bacillus subtilis, Salmonella typhimurium, and Chlorobium vibrioforme but does not contain the amino acid sequence derived from the N terminus of the previously purified GluTR protein (Rieble, S., and Beale, S . I . (1991) J . Biol . Chem . 266, 9740-9745) . These experiments are the first direct demonstration of GluTR activity of the HemA protein and provide further evidence for two pathways of ALA formation in prokaryotes. Am J Med, 1992 Apr 6, 92(4A), 52S - 57S Fluoroquinolone (Lomefloxacin) International Surveillance Trial: a report of 30 months of monitoring in vitro activity; Jones RN; The antimicrobial activity and spectrum of lomefloxacin were assessed by standardized disk diffusion methods in 36 countries . More than 500,000 facultative organisms were tested during the first 30 months of a 3-year monitoring interval . Lomefloxacin demonstrated inhibition (zones greater than or equal to 19 mm) of greater than 90% of Enterobacteriaceae, greater than 99% of Moraxella (Branhamella) catarrhalis, greater than 98% of Haemophilus spp., and 91% of Staphylococcus aureus strains . Pseudomonas spp., especially Pseudomonas aeruginosa (18% resistance), were considered moderately susceptible, as were most strains of streptococci and enterococci . Some variation of national/regional fluoroquinolone resistance rates was observed, using lomefloxacin as an index or indicator drug, with the highest numbers of resistant strains being isolated in France . However, these data demonstrated a wide spectrum of lomefloxacin activity in all nations monitored. Am J Med, 1992 Apr 6, 92(4A), 26S - 32S Multiple-dose pharmacokinetics of lomefloxacin: rationale for once-a-day dosing; Mant TG; Six dosage regimens of oral lomefloxacin, a new difluorinated quinolone, were given to healthy volunteer subjects for 7 days in a randomized, placebo-controlled trial to evaluate pharmacokinetics and tolerability and to determine the optimum dosage schedule . Single daily doses of lomefloxacin up to 800 mg and multiple doses up to 600 mg twice daily (1,200 mg/day) were well tolerated . At all dose levels and schedules, lomefloxacin was well absorbed and achieved peak plasma concentrations approximately 1 hour after administration . Urine concentrations were approximately 100 times the plasma concentrations . Elimination half-lives of 7-8 hours were found for all dosage regimens . Steady-state was achieved on the second day of dosing . Little accumulation was observed . A 400 mg oral dose provided a mean peak plasma concentration of 3.43 micrograms/mL, and trough concentrations at steady state that were above the minimum inhibitory concentration for 90% (MIC90) of most common Enterobacteriaceae . The 400 mg dose produced a urine concentration of greater than 80 micrograms/mL during the 12- to 24-hour period after the dose, thus exceeding the MIC90 for clinical isolates such as Pseudomonas aeruginosa, Serratia marcescens, and methicillin-susceptible and -resistant Staphylococcus aureus . There was good agreement between the results of this study and previously reported single-dose data . In summary, lomefloxacin's rapid absorption, long half-life, and high sustained plasma and urine concentrations should permit effective once-daily administration in many clinical situations. Avian Dis, 1992 Apr-Jun, 36(2), 459 - 62 Cloacal flora isolated from wild black-bellied whistling ducks (Dendrocygna autumnalis) in Laguna La Nacha, Mexico; Aguirre AA et al.; Cloacal swabs from 110 adult black-bellied whistling ducks trapped at Laguna La Nacha, Tamaulipas, Mexico, were cultured to determine the prevalence of normal and potentially pathogenic bacteria . Twenty-five gram-negative enterobacteria and four gram-positive cocci were isolated . The most common isolates included Escherichia coli (54%), Staphylococcus spp . (29%), Streptococcus spp . (22%), Aeromonas hydrophila (15%) Enterobacter cloacae (14%), and Micrococcus sp . (14%) . The implications of whistling ducks as possible reservoirs of pathogenic bacteria are discussed. FEMS Microbiol Lett, 1992 Apr 1, 71(1), 95 - 100 Mutation of serine residue 318 in the class C beta-lactamase of Enterobacter cloacae 908R; Jacobs C et al.; The involvement of the serine residue 318 in the specificity of a class C beta-lactamase was investigated . Multiple site-directed mutants at this position were generated using a polymerase chain reaction technique . These mutants were then probed for their activity towards various beta-lactam compounds . One mutant, S318G was further purified and its physico-chemical and catalytic properties determined . It was shown that the observed minimal inhibitory concentration values of this mutant could be correlated to its kinetic properties using a 'diffusion-hydrolysis' model . However, the data showed that residue 318 has little influence on the specificity of class C beta-lactamases. FEMS Microbiol Lett, 1992 Apr 1, 71(1), 89 - 94 Does high level production of SHV-type penicillinase confer resistance to ceftazidime in Enterobacteriaceae? Petit A, Ben Yaghlane-Bouslama H, Sofer L, Labia R. We report the isolation of a clinical isolate of Klebsiella pneumoniae that showed resistance to ceftazidime (MIC: 8 micrograms/ml), susceptibility to aztreonam (MIC: 2 micrograms/ml) and cefotaxime (MIC: 0.015 micrograms/ml) . A synergistic effect between clavulanic acid and ceftazidime or aztreonam against this strain was also observed . The strain hyperproduced SHV-1 penicillinase (990 U/g) which is encoded by a self-transferrable plasmid of at least 150 kb . That the ceftazidime-resistance phenotype could be due to hyperproduction of SHV-1 penicillinase is supported by the study of a spontaneous ceftazidime-resistant mutant in vitro obtained from an Escherichia coli strain containing plasmid p453 encoding the SHV-1 . Indeed, this mutant hyperproducing SHV-1 (2200 U/g) was resistant to ceftazidime (MIC: 16 micrograms/ml) and aztreonam (MIC: 8 micrograms/ml) but susceptible to cefotaxime (MIC: 0.03 ng/ml) . Clavulanic acid showed a synergistic effect when associated with ceftazidime or aztreonam . In contrast, the hyperproduction of TEM-1 (790 U/g) did not confer a ceftazidime- and aztreonam-resistant phenotype while hyperproduction of both TEM-1 and SHV-1 increased the resistance to amoxycillin/clavulanic acid and to cephalothin. J Antimicrob Chemother, 1992 Apr, 29(4), 405 - 13 Prevalence of a plasmid-mediated type II dihydrofolate reductase gene among trimethoprim-resistant urinary pathogens in Greek hospitals; Tsakris A et al.; The genetic basis of trimethoprim resistance was examined in 24 Klebsiella pneumoniae, 27 Enterobacter cloacae, five Enterobacter aerogenes and nine Serratia marcescens urinary isolates from five hospitals in Greece . Analysis of the 65 isolates by serotyping and phage-typing identified 53 distinct strains . Thirty-eight isolates (15 K . pneumoniae, 19 E . cloacae, two E . aerogenes and two S . marcescens) hybridized with a probe specific for a gene encoding type II dihydrofolate reductase (DHFR) . Three of the K . pneumoniae and four of the E . cloacae isolates which reacted with this probe also hybridized with probes specific for type I DHFR and transposon Tn7 . Two E . cloacae isolates hybridized only with the probe for type I DHFR, while a further three isolates hybridized only with the type I DHFR and Tn7 probes . None of the isolates hybridized with a probe for type V DHFR . The plasmids in transconjugants derived from 40 isolates were analysed by digestion with restriction enzymes and Southern blotting . Eighteen (45%) of the donors (12 K . pneumoniae and 6 E . cloacae) produced transconjugants containing plasmids of about 95 kb in size, while transconjugants from the other donors had plasmids in the range 100-185 kb . Of the 18 transconjugants containing a 95 kb plasmid, 15 had similar restriction endonuclease digest patterns, although they varied in terms of the range of antimicrobial resistances which they encoded . When EcoRI digests of these 15 plasmids were hybridized with the type II DHFR probe, a 23 kb common band reacted with the probe.(ABSTRACT TRUNCATED AT 250 WORDS) Microbiologica, 1992 Apr, 15(2), 135 - 47 Antibiotic susceptibility patterns surveillance and clinical distribution of Enterobacteriaceae; Garbagnoli P et al.; 3700 strains of Enterobacteriaceae clinical isolates were tested by automated devices for susceptibility to several antimicrobial agents widely used in clinical practice . Amikacin demonstrated the greatest in vitro activity whereas ampicillin and mezlocillin were the least active . Finally gentamicin and nalidixic acid had a similar activity to recently introduced cephalosporins . The bacterial species widely isolated were grouped in three clusters according to the clinical body site of isolates: several discrepancies emerged from the study of antibiotic susceptibilities of strains obtained from different body site sources . Source could be correlated with bacterial pattern of resistance. Mol Microbiol, 1992 Apr, 6(7), 833 - 41 Phosphorylation of IcsA by cAMP-dependent protein kinase and its effect on intracellular spread of Shigella flexneri; d'Hauteville H et al.; Shigella flexneri, a Gram-negative bacillus belonging to the family Enterobacteriaceae, causes bacillary dysentery in humans by invading colonic epithelial cells . Processes by which epithelial cells, which are not professional phagocytes, may limit the spread of the invading microorganisms are poorly understood . This paper shows that IcsA (VirG), a 120 kDa bacterial outer membrane protein responsible for intracellular and cell-to-cell spread through polymerization of actin, is a major substrate for phosphorylation by cyclic-dependent protein kinases . Site-directed mutagenesis of a sequence encoding phosphorylation consensus motif SSRRASS, located at residues 754-760, almost completely abolished the ability of this protein to be phosphorylated by protein kinase A . Such mutants expressed a 'super lcs' phenotype, characterized by an increased capacity to spread from cell-to-cell during the first three hours of infection in the HeLa cell infection assay . These data suggest that host-cell phosphorylation of key virulence proteins located on the bacterial surface may represent a significant host defence mechanism during the invasion process. J Antimicrob Chemother, 1992 Apr, 29 Suppl A, 7 - 12 In-vitro activity of cefpirome against isolates from patients with urinary tract, lower respiratory tract and wound infections; Schafer V et al.; The in-vitro activity of cefpirome, a new injectable cephalosporin, was compared with that of several other antibiotics against bacterial isolates from hospitalized patients with lower respiratory tract infections, urinary tract infections and wound infections . Minimum inhibitory concentrations were determined for 874 strains against 16 antibiotics using a microtitration technique . Cefpirome showed a very broad spectrum of activity against most pathogens tested . The spectrum included organisms such as Staphylococcus spp., enterococci, Enterobacter spp., and Pseudomonas spp . which are frequently resistant to third generation cephalosporins. J Antimicrob Chemother, 1992 Apr, 29 Suppl A, 19 - 24 Predominant pathogens in hospital infections; Jarvis WR et al.; To determine the distribution of pathogens causing nosocomial infections in United States hospitals, we analysed data from the National Nosocomial Infections Surveillance (NNIS) System . From October 1986 to December 1990, amongst hospitals conducting hospital-wide surveillance, the five most commonly reported pathogens were Escherichia coli (13.7%), Staphylococcus aureus (11.2%), enterococci (10.7%), Pseudomonas aeruginosa (10.1%), and coagulase-negative staphylococci (9.7%) . The commonest pathogens reported by site included, bloodstream: coagulase-negative staphylococci, S . aureus, enterococci, E . coli, and Candida spp.; lower respiratory tract infection: S . aureus, P . aeruginosa and Enterobacter spp.; surgical wound infection: S . aureus, enterococci and coagulase-negative staphylococci; and urinary tract infection: E . coli, enterococci, and P . aeruginosa . Among hospitals conducting intensive care unit (ICU) surveillance, the commonest pathogens were P . aeruginosa (12.4%), S . aureus (12.3%), coagulase-negative staphylococci (10.2%), Candida spp . (10.1%), Enterobacter spp . and enterococci (8.6% each) . In the ICUs, the commonest pathogens found in the bloodstream were coagulase-negative staphylococci, S . aureus, and enterococci; in lower respiratory tract infections P . aeruginosa, S . aureus, and enterococci; in surgical wound infections enterococci, coagulase-negative staphylococci, and Enterobacter spp . and in urinary tract infections Candida spp., E . coli, enterococci, P . aeruginosa, and Enterobacter spp . These data show that S . aureus, E . coli and P . aeruginosa remain important nosocomial pathogens, that coagulase-negative staphylococci, enterococci and C . albicans are pathogens of increasing importance, and that the distribution of pathogens differs by site and hospital location. J Antimicrob Chemother, 1992 Apr, 29 Suppl A, 1 - 6 Factors involved in the enhanced efficacy against gram-negative bacteria of fourth generation cephalosporins; Hancock RE et al.; The fourth generation cephalosporins, cefpirome and cefepime, demonstrate better activity against strains of Enterobacter cloacae with derepressed beta-lactamase than the third generation compounds cefotaxime and ceftriaxone . Several methodological refinements were used to measure the parameters, predicted by the Zimmermann-Rosselet equation to be important in the efficacy of beta-lactams . Outer membrane permeability was measured by a novel HPLC method . The kinetics of interaction of purified beta-lactamase with beta-lactams were estimated to calculate the inhibition and catalytic constants . The periplasmic concentration of beta-lactams leading to growth inhibition of cells was determined by substituting the above parameters into the Zimmermann-Rosselet equation . Consideration of these three factors allowed accurate prediction of MICs in isogenic E . cloacae strains with differing porin or beta-lactamase contents . The fourth generation cephalosporins had markedly reduced affinity for beta-lactamase and increased outer membrane permeability when compared to the third generation cephalosporins . Such advantages were only partly offset by a lower stability of complexes with beta-lactamase and reduced affinity for their targets. Appl Environ Microbiol, 1992 Apr, 58(4), 1227 - 32 Self-similar colony morphogenesis by gram-negative rods as the experimental model of fractal growth by a cell population; Matsuyama T et al.; The ability to form a fractal colony was shown to be common among several species of the family Enterobacteriaceae . Bacterial spreading growth in a two-dimensional field of nutrient concentration was indicated to be important for this experimental self-similar morphogenesis . As a basic analogy, the diffusion-limited aggregation model was suggested . Fractal dimensions of colonies were mostly in the range of values from 1.7 to 1.8, similar to those of the two-dimensional diffusion-limited aggregation model . Bacterial characteristics and culture conditions inducing changes in fractal patterns and growth rates were identified . The contribution of the bacterial multicellular nature to fractal morphogenesis is discussed. J Antibiot (Tokyo), 1992 Apr, 45(4), 521 - 6 RU 29 246, the active compound of the cephalosporin-prodrug-ester HR 916 . II . Stability to beta-lactamases and affinity for penicillin-binding proteins; Markus A et al.; The aminothiazolyl-cephalosporin RU 29 246, the active metabolite of the prodrug-ester HR 916, is active against strains producing the widespread plasmid-encoded TEM-1, TEM-2 and SHV-1 beta-lactamases . Except for TEM-7 the activity of RU 29 246 against strains producing extended broad spectrum beta-lactamases (TEM-3, TEM-5, TEM-6, SHV-2, SHV-4, SHV-5, CMY-1, CTX-M), however, is low . Relative hydrolysis rates of RU 29 246 are comparable with those of cefpodoxime, the active metabolite of CS-807, and are extremely low for the TEM-1 and SHV-1 beta-lactamases . The compound demonstrates remarkable inhibitory activity against the chromosomal beta-lactamase of Enterobacter cloacae P99 . In the presence of 1.7 microM this enzyme loses 50% of its activity . At concentrations of 0.43, 0.003