Ciba Found Symp, 1997, 207, 76 - 86; discussion 86-92 The effect of monitoring of antibiotic use on decreasing antibiotic resistance in the hospital; Giamarellou H et al.; In Greece, antibiotic over-consumption and high resistance rates run in parallel . In the spring of 1989 surveillance of 12500 Gram-negative strains, derived from 55 hospitals from all over Greece, revealed that resistance rates of Pseudomonas aeruginosa, Enterobacter spp., Klebsiella spp . and Acinetobacter spp . to antimicrobial agents introduced after 1985 exceeded 50% . As a consequence, the application of (1) rules of hospital hygiene, (2) educational small group programs, and (3) an antibiotic policy aiming to restrict antibiotic use, was decided in Laiko General Hospital . Since 1989, imipenem, the newer quinolones, vancomycin, aztreonam and third-generation cephalosporins were only ordered to the hospital pharmacy after completion of a specific request form, which since 1991 has been more detailed and which can be signed only by physicians with interest in infectious diseases . In 1991, in cooperation with the pharmacy, an audit program was added requiring a final inspection of the already approved request forms by an infectious diseases specialist . Any disagreement was discussed with the physicians in charge . Consumption data were analysed monthly and discussed with each department . Newer antibiotic consumption in a selected month (November) of three consecutive years, before (1991) and after the application of the audit program (1992-1995) has been analysed . Results reveal a decrease in consumption of restricted antibiotics, especially in surgical departments and in kidney transplantation units, without simultaneous increase in consumption of the non-restricted compounds . Since 1994, resistance has decreased remarkably . However, the resistance of quinolones is increasing steeply . Consequently, for the last 12 months quinolones have been removed from the hospital formulary . An audit program requires close co-operation of physicians, pharmacists and, particularly, of surgeons, in the application of a correct prophylaxis regimen . It seems to be efficacious in reducing both resistance rates and total antibiotic consumption. Zentralbl Bakteriol, 1997 Jan, 285(2), 234 - 44 An apparent outbreak of infection with Acinetobacter calcoaceticus reconsidered after investigation by pyrolysis mass spectrometry; Freeman R et al.; In a previously reported apparent outbreak of infection due to Acinetobacter calcoaceticus on a Regional Burns Unit in which both clinical and environmental isolates were available for study, investigations of the organisms by electrophoretic typing of surface proteins, plasmid profiling and antibiograms were inconclusive and unable to identify a single epidemic strain of the organism . The same collection of isolates has been analysed for inter-strain comparison by pyrolysis mass spectrometry (PyMS) . PyMS analysis suggested that a few isolates were very different from the majority but that most of the collection comprised a group of closely similar but nonetheless distinct isolates . These isolates may well be representatives of a limited variety of strains occupying an ecological niche but not yet a single emergent strain . The ability of PyMS to detect a single epidemic strain of A . calcoaceticus when present in such a collection of isolates was demonstrated by analysis of a "constructed outbreak collection", using some of the original isolates . This study illustrates the versatility of PyMS for inter-strain comparison studies of species not yet amenable to conventional typing methods . The application of rapid, highly discriminatory, high-volume inter-strain comparison methods such as PyMS to apparent outbreaks of nosocomial infection is likely to reveal patterns of organism acquisition other than point-source transmission. J Antimicrob Chemother, 1997 Jan, 39(1), 53 - 61 In-vitro pharmacodynamic studies of piperacillin/tazobactam with gentamicin and ciprofloxacin; Gould IM et al.; Six isolates each of Enterococcus faecium, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Stenotrophomonas maltophilia, Pseudomonas aeruginosa, Citrobacter spp., Serratia spp., Acinetobacter spp . and Enterobacter spp . (total 60 strains) were studied against the combination of piperacillin/tazobactam plus gentamicin or ciprofloxacin at physiological concentrations by the microtitre chequerboard method incorporating simultaneous time-kill curves . Tazobactam was fixed at 4 mg/L . Gentamicin plus piperacillin/tazobactam was a synergic combination against 28 strains at 2 h, 51 at 5 h and 54 at 24 h as assessed by time-kill curves and synergic or additive (FBC index < or = 1) against all 60 strains at 24 h by chequerboards . The corresponding figures for ciprofloxacin plus piperacillin/tazobactam were seven, 26, 52 and 58 respectively . Antagonism (FBC index > or = 4) was demonstrated for one strain to each combination at 24 h . There were no significant differences between FIC indices and FBC indices for each antibiotic combination . Gentamicin plus piperacillin/tazobactam gave > or = 3 log kill for 47 strains by 2 h, 56 by 5 h and 59 by 24 h . Ciprofloxacin plus piperacillin/tazobactam gave > or = 3 log kill for 22 strains by 2 h, 36 by 5 h and 56 by 24 h . In conclusion both antibiotic combinations at physiological concentrations were synergic or additive at 24 h for the majority of strains tested although notably gentamicin plus piperacillin/tazobactam gave faster kill . Antagonism was rarely seen . Both combinations are likely to prove beneficial for treatment of serious infections. Indian J Med Res, 1997 Jan, 105, 15 - 21 Upper urinary tract stones & Ureaplasma urealyticum; Dewan B et al.; Extensive culture of stones and of pre-operative and renal pelvic urine for isolation of bacteria and Ureaplasma urealyticum were performed in 70 patients of nephrolithiasis . Stones were subjected to biochemical analysis and scanning electron microscopy . Micro-organisms were isolated from 33 (47%) of 70 renal stones . Of the 38 species of micro-organisms isolated, 14 were urea-splitting (U . urealyticum 2; Klebsiella pneumoniae 8; Morganella morganii 1; Acinetobacter spp 3) and 24 were nonurea splitting . U . urealyticum was cultured from the renal stones of two patients . Pelvic urine, unlike voided urine did reflect the bacteriology of the stone . Biochemically, 55 stones (79%) were calcium oxalate phosphate stones, 10 (14%) were calcium oxalate stones and 5 (7%) were uric acid stones . None of the stones were found to be of struvite composition . These data suggest that infection stones are uncommon in this part of the country . Further, infection of renal stones with fastidious organisms like U . urealyticum and multi-drug resistant bacteria necessitate their removal to ensure complete cure. Microbiology, 1997 Jan, 143 ( Pt 1), 93 - 9 Plasmid-encoded genes specifying aniline oxidation from Acinetobacter sp . strain YAA; Fujii T et al.; Acinetobacter sp . strain YAA is able to use aniline and o-toluidine as the sole carbon and energy source . This strain has several different plasmids and acridine orange curing suggested that aniline utilization in strain YAA was plasmid-encoded . The gene cluster involved in aniline oxidation was cloned in Escherichia coli JM109 from the total plasmid DNA of strain YAA . A recombinant E . coli containing an 18.5 kb insert fragment showed yellow colouration on aniline-containing plates, indicating the formation of 2-hydroxymuconic semialdehyde from aniline . In addition, subcloning of a 9.0 kb SalI fragment from the insert in E . coli resulted in the accumulation of catechol . Southern hybridization studies indicated that the aniline oxygenase gene (atdA) was present on one of the plasmids, pYA1 . These results suggest that in strain YAA aniline is degraded via catechol through a pathway involving meta-cleavage of the benzene-ring by plasmid-encoded genes including atdA. Pediatr Infect Dis J, 1997 Jan, 16(1), 18 - 23 Neonatal airway colonization with gram-negative bacilli: association with severity of bronchopulmonary dysplasia; Cordero L et al.; BACKGROUND: Airway colonization with Gram-negative bacilli (GNB) and Gram-positive cocci (GPC) is common in mechanically ventilated neonates . Whether GNB are related to nosocomial bloodstream infection (BSI) and/or to the severity of bronchopulmonary dysplasia (BPD) is unknown . METHODS: We prospectively examine this relationship using a cohort design . Data from 260 < or = 1250-g birth weight inborn infants (1991 to 1995) intubated > or = 2 weeks included 917 serial tracheal cultures and 583 blood cultures . The severity of BPD was assessed by duration of mechanical ventilation, oxygen dependency at 36 weeks of postconceptional age and the use of home oxygen supplementation . RESULTS: After 2 weeks of ventilation, 80% of the infants were colonized with GPC (Staphylococus epidermidis and Staphylococcus haemolyticus in 90% of the cases) . Superimposed on 36% of these infants was GNB airway colonization with Klebsiella pneumoniae (25%), Enterobacter cloacae (25%), Escherichia coli (25%), Pseudomonas aeruginosa (10%), Serratia marcescen (10%), Acinetobacter baumannii and Haemophilus influenzae (5%) . Comparison between 174 GPC- and 86 GNB-colonized infants showed that demographics, birth weight, gestational age, perinatal risk factors and mortality were similar . Fifteen percent of GNB-colonized infants developed BSI caused by GNB and 14% developed BSI caused by GPC . No significant temporal relationship between airway colonization and BSI was noted . GNB infants were ventilated longer and required oxygen at 36 weeks of postconceptional age and home oxygen supplementation twice as often as infants colonized only with GPC . GNB colonization was a predictor of severe BPD after controlling for ventilation . Ureaplasma colonization occurred in 28% of GNB-colonized and 33% of noncolonized infants and was not a predictor of BPD severity . CONCLUSION: GNB airway colonization creates a moderate risk for BSI . Antibiotic treatment does not regularly eradicate GNB . GNB airway colonization is associated with severe BPD, but further studies will be necessary before therapeutic efforts to eradicate GNB from the airways should be undertaken. Chemotherapy, 1997 Jan-Feb, 43(1), 21 - 6 Antibacterial activity of cefpodoxime in vitro; Liu YC et al.; Cefpodoxime proxetil is a new orally administered prodrug which is absorbed and de-esterified by the intestinal mucosa to release the third-generation cephalosporin, cefpodoxime, and which is undergoing in vitro and in vivo evaluations . Using the standard agar dilution method, we compared the in vitro activity of this drug with other oral cephalosporins and quinolones against 637 recent clinical isolates from Kaohsiung Veterans General Hospital in Taiwan . Against Escherichia coli and Klebsiella pneumoniae, cefpodoxime showed excellent activity, inhibiting over 90% of these isolates at 1 mg/l . Like other oral drugs of its class, it had little activity against Pseudomonas aeruginosa and Acinetobacter spp . Against Haemophilus influenzae, irrespective of beta-lactamase production, its activity was similar to comparative drugs . Against methicillin-susceptible Staphylococcus aureus, cefpodoxime showed moderate activity, inhibiting 90% of these isolates at 4 mg/l, whereas it was inactive against methicillin-resistant S . aureus . However, all cephalosporins have shown little in vivo activity against methicillin-resistant S . aureus regardless of in vitro results . Cefpodoxime was inactive against Enterococcus spp . Against other streptococci, its activity was similar to other oral cephalosporins and quinolones tested . The results of this in vitro study indicated that oral administration of cefpodoxime should be an ideal agent in the empirical outpatient treatment for community-acquired cutaneous, respiratory and urinary tract infections. Clin Infect Dis, 1997 Jan, 24 Suppl 1, S46 - 62 The most frequent aminoglycoside resistance mechanisms--changes with time and geographic area: a reflection of aminoglycoside usage patterns? Aminoglycoside Resistance Study Groups; Miller GH et al.; The aminoglycoside resistance mechanisms revealed by two surveys in Europe and other countries have been compared to those revealed in earlier studies . Mechanisms have become more complex in all bacterial groups . In Providencia, Serratia, Pseudomonas, Acinetobacter, and Staphylococcus species isolates, genus-specific mechanisms were very common, and it was not possible to see differences between different geographic areas . In other Enterobacteriaceae, the increasing complexity of mechanisms was most often caused by combinations of gentamicin-modifying enzymes with AAC(6')-I, which acetylates amikacin but not gentamicin . The occurrence of these combinations varied by geographical region and among hospitals . The frequency of these combinations correlated with aminoglycoside usage in either the geographical regions or in individual hospitals . These broad-spectrum combinations occurred most frequently in Citrobacter, Enterobacter, and Klebsiella species but also occurred in Escherichia, Morganella, Proteus, Salmonella, and Shigella species . Often the only clinically available aminoglycoside that retained its normal activity was isepamicin. Appl Environ Microbiol, 1997 Jan, 63(1), 71 - 6 Identification and characterization of a Pantoea citrea gene encoding glucose dehydrogenase that is essential for causing pink disease of pineapple; Cha JS et al.; Pantoea citrea, a member of the family Enterobacteriaceae, causes pink disease of pineapple, whose symptom is characterized by the formation of pink to brown discolorations of the infected portions of the pineapple fruit cylinder upon canning . Molecular genetic approaches were applied to elucidate the mechanism responsible for this fruit discoloration . A P . citrea mutant strain, CMC6, defective in its ability to cause pink disease and fruit discoloration, was generated by nitrosoguanidine mutagenesis . A DNA fragment that restored these activities was isolated by screening a genomic cosmid library of P . citrea . A large open reading frame of 2,361 bp, identified by nucleotide sequencing of a subclone of the complementing DNA, showed high similarities to identified genes encoding glucose dehydrogenase (GDH) in Escherichia coli, Acinetobacter calcoaceticus, and Gluconobacter oxydans . The predicted amino acid sequence of GDH of P . citrea was identical to known GDHs in these bacteria by 54, 44, and 34%, respectively . GDH of P . citrea has a predicted molecular mass of 86.2 kDa, contains a conserved binding domain for the cofactor pyrroloquinoline quinone, and possesses GDH activity as demonstrated by biochemical assay . GDH is the key branch point enzyme leading to the biosynthesis of gluconate, which in turn serves as the substrate leading to the formation of 2-ketogluconate, 2,5-diketogluconate, 6-phosphogluconate, and 2-keto-6-phosphogluconate . Addition of gluconate to CMC6 restores the juice- and fruit-discoloring activity . Although the pigments formed by heating (or canning) have not been identified, it is clear that GDH is one of the enzymes required for pigment formation leading to pink disease. Curr Microbiol, 1997 Jan, 34(1), 43 - 8 Phosphate Release and Uptake by Pure Cultures of Acinetobacter sp.: Effect of the Volatile Fatty Acids Concentration Rustrian E, Delgenes JP, Moletta R. Phosphorus release and uptake by pure cultures of Acinetobacter strains were investigated under anaerobic and aerobic conditions respectively . Tests were performed to study the relationship between phosphorus release-storage reaction and behavior of extracellular organic substrates: acetic, propionic, and butyric acids have been used at four concentrations (50, 100, 500, and 1000 mg &middot; L-1) in the anaerobic step of biological phosphorus removal . The results obtained depend on the strain and the volatile fatty acid (VFA) used . Phosphorus released under anaerobic condition was not always related to the amount of VFA or phosphorus consumed . Phosphorus uptake (P-uptake) in the aerobic step was found to be independent of phosphorus release rates . The best phosphorus uptake rates were obtained by Acinetobacter lwoffi ATCC21130 and Acinetobacter calcoaceticus Genoespecie SUCT-5 with butyric acid as carbon source. Mol Cell Probes, 1996 Dec, 10(6), 405 - 11 Differentiation of seventeen genospecies of Acinetobacter by multiplex polymerase chain reaction and restriction fragment length polymorphism analysis; Nowak A et al.; The 17 described genomic species (DNA groups) of the genus Acinetobacter, including the type strains of the seven named species, were studied by using a multiplex PCR . The multiplex PCR assay combined two primer sets (rA1 and rA2 for recA gene target; rib1 and rib2 for 16S rDNA sequence) in a single reaction . Restriction analysis with two enzymes (Mbol and Hinfl) of the enzymatically amplified products allowed identification of all genospecies . This technique proved to be a rapid and reliable method for the identification of the Acinetobacter genomic species including the closely related DNA groups (1, 2, 3, 13) . The results of this study suggest that the proposed method can be used for the identification of Acinetobacter spp . and as such may help to elucidate the ecology and clinical significance of the different species of this genus. J Antimicrob Chemother, 1996 Dec, 38(6), 1079 - 83 Characterisation of DNA gyrase and measurement of drug accumulation in clinical isolates of Acinetobacter baumannii resistant to fluoroquinolones; Moreau NJ et al.; Twelve clinical isolates of Acinetobacter baumannii highly resistant to pefloxacin (MIC > or = 32 mg/L) and to ciprofloxacin (MIC > or = 16 mg/L), were studied . A susceptible isolate used as a reference (MIC of 0.032 and 0.25 mg/L for ciprofloxacin and pefloxacin, respectively) accumulated 85 mg of pefloxacin per litre of cell volume within 10 min, from a solution containing 10 mg/L of antibiotic . One resistant isolate accumulated the same amount of pefloxacin, while the 11 others accumulated between 40 and 70 mg/L of cell volume . The differences between reference and resistant isolates with respect to ciprofloxacin and sparfloxacin accumulation were less pronounced . There were no apparent differences in the outer membrane protein profiles of susceptible and resistant isolates . DNA gyrase was isolated from four A . baumannii and the minimum concentration of fluoroquinolones, required to inhibit gyrase-catalysed supercoiling of plasmid DNA was 5- to 80-fold higher for the resistant isolates than for the reference strain . Although most isolates showed some degree of reduced fluoroquinolone accumulation, a DNA gyrase mutation was more likely to be the main mechanism of the high level resistance encountered. Bioorg Med Chem, 1996 Dec, 4(12), 2135 - 49 Synthesis and structure-activity relationships of cephalosporins, 2-isocephems, and 2-oxaisocephems with C-3' or C-7 catechol or related aromatics; Tsuji K et al.; A series of cephalosporins, 2-isocephems, and 2-oxaisocephems with C-3' catechol-containing (pyridinium-4-thio)methyl groups and 2-isocephems with C-7 catechol related aromatics have been prepared and evaluated for antimicrobial activity . It turns out that these compounds have highly potent activity against Gram-negative bacteria, especially resistant pathogens such as Pseudomonas aeruginosa . The most active compound of the series was (6S,7S)-7-{2-(2-aminothiazol-4-yl)-2-{(Z)-{(1,5-dihydroxy-4-pyr idon-2-yl) methoxy}imino}acetamido}-3-{{{(4-methyl-5-carboxymethyl)thiazol-2- yl} thio}methyl}-8-oxo-1-aza-4-thiabicyclo {4.2.0} oct-2-ene-2-carboxylic acid which exhibited potent in vitro activity against clinically isolated P, aeruginosa and Acinetobacter baumanii which is also resistant to many anti-infectives, and good in vivo efficacy against clinically isolated P aeruginosa. Nephrol Dial Transplant, 1996 Dec, 11(12), 2466 - 71 Peritoneal nitric oxide is a marker of peritonitis in patients on continuous ambulatory peritoneal dialysis; Yang CW et al.; Nitric oxide plays an important role in mediating the inflammatory process . The aim of this study was to evaluate if nitric oxide production was increased during peritonitis in patients receiving continuous ambulatory peritoneal dialysis (CAPD), and the association with the prognosis . The study population comprised 21 patients with 22 episodes of peritonitis . Fifteen patients without peritonitis were controls . Nitrate was measured by HPLC and nitrite by the Griess method, to reflect nitric oxide production . Peritoneal dialysate effluent and plasma were collected from six patients during peritonitis and 1 week after treatment to study changes in dialysate:plasma ratio . In 15 patients, nitrite was measured during peritonitis and every 3 days for 2 weeks or until normalized for evolutional changes . The dialysate:plasma ratios of nitrate and nitrite during peritonitis were reduced 26% and 41.5%, respectively, after 1 week of treatment, indicating the peritoneal production of nitric oxide during peritonitis . In the evolutional study, a 5.1-fold increase of peak nitrite levels in bacterial peritonitis (n = 13) and a 2.5-fold increase in fungal peritonitis (n = 3) were observed compared to controls . Nitrite gradually declined to control levels (9.3 +/- 7.2 days) after effective antibiotic treatment, but took longer than to normalize leukocyte count in the peritoneal dialysate effluent (3.9 +/- 1.9 days) . In four patients with refractory peritonitis (Candida infection in three, Acinetobacter infection in one), the nitrite levels remained elevated 2-fold despite treatment, and the catheters were removed . It is concluded that nitrite levels in peritoneal dialysate effluent may serve as a marker to assess treatment efficacy in CAPD patients with peritonitis. J Chemother, 1996 Dec, 8(6), 457 - 64 Efficacy and safety of once-daily amikacin in combination with ceftazidime in critically ill adults with severe gram-negative infections; Fayed DF et al.; Forty critically ill adult patients with severe Gram-negative infection were treated with once-daily amikacin combined with ceftazidime . The mean age was 56.6 +/- 19 years and mean APACHE II score was 22.7 +/- 6.6 . Forty percent of patients required mechanical ventilation . The mean creatinine clearance at onset of therapy was 59.4 +/- 28 ml/min . All bacterial isolates were sensitive to amikacin . Fixed doses of amikacin 15 mg/kg, 12 mg/kg, and 8 mg/kg body weight were given once daily to patients with estimated creatinine clearance of > 80 ml/min., 50-80 ml/min., and < 50 ml/min, respectively . Forty-two causative gram-negative bacteria were isolated from 40 patients . The most common bacteria were Pseudomonas aeruginosa (18), and Escherichia coli (10) . Overall clinical success and bacteriological eradication occurred in 85% and 87.5% of patients; 78.9% and 79% of patients with hospital-acquired infections; 90.5% and 95.2% of patients with community-acquired infections; and 62.5% and 81.3% of patients requiring mechanical ventilation, respectively . Therapeutic failure was documented in 15% of patients . Death due to infection was scored in two patients . The remaining were all due to persistence of the initial causative bacteria in patients with hospital-acquired infections . Persistence was documented with Ps . aeruginosa (2), Serratia spp . (1), and Acinetobacter spp . (1) . Overall mortality occurred in 22.5% patients . Death unrelated to infection occurred in 7 patients . There was no clinical evidence of ototoxicity in any of our patients, however, nephrotoxicity was documented in 5% . In conclusion, once-daily amikacin combined with ceftazidime is practical, efficacious and probably safe in critically ill infected patients. J Chemother, 1996 Dec, 8(6), 416 - 9 In vitro activity of ampicillin-sulbactam against clinical multiresistant Acinetobacter baumannii isolates; Gales AC et al.; We evaluated the in vitro activity of ampicillin-sulbactam in comparison with that of broad-spectrum antimicrobial agents against Acinetobacter baumannii isolates . Two hundred and twelve clinical isolates collected between January 1993 and March 1995 from two tertiary hospitals located in Sao Paulo, Brazil were tested for susceptibility by the disk diffusion method against several broad-spectrum antimicrobial agents, including imipenem, ciprofloxacin, ceftazidime, aztreonam, amikacin, and polymyxin B . All strains were susceptible to polymyxin B . The second most active compound was the combination ampicillin-sulbactam (88% susceptibility) . Only 79% of the isolates were susceptible to imipenem . Ciprofloxacin was active against 60 (28%) and amikacin against 34 (16%) isolates . Ceftazidime was the most active cephalosporin; however, only 9% of the isolates were susceptible to this compound . Both aztreonam and ampicillin alone showed very poor activity against this species (1% susceptibility) . The prevalence of severe infections due to A . baumannii is increasing very rapidly in the tertiary hospitals of Sao Paulo and there are very few options for the treatment of these infections . Polymyxin B is invariably in vitro active against this species; however, this compound can cause severe side effects and is not commercially available for intravenous use in Brazil and in several other countries . Our results indicated that the combination ampicillin-sulbactam may be an alternative drug for the treatment of infections due to multiresistant A . baumannii; however, further studies are necessary to evaluate the clinical role of this compound for the treatment of severe infections. J Hosp Infect, 1996 Dec, 34(4), 279 - 89 Secondary carriage with multi-resistant Acinetobacter baumannii and Klebsiella pneumoniae in an adult ICU population: relationship with nosocomial infections and mortality; Garrouste-Orgeas M et al.; A one year prospective, observational survey was performed to evaluate the abnormal carriage of multi-resistant Klebsiella pneumoniae and/ or Acinetobacter baumannii, to determine associated risk factors for carriage, and to correlate the abnormal carriage with infectious morbidity and mortality in the intensive care unit (ICU) of a University Hospital . Two hundred and ninety-eight patients who stayed in the ICU > 48h, and were not neutropenic, were studied . Salivary and rectal samples were obtained on admission and weekly until discharge . Out of 265 evaluable patients, 88 (33%) developed oropharyngeal and/or rectal carriage within a median of nine days . Three factors were significantly associated with abnormal carriage: higher 'severity of illness' score on admission, a threefold increase in ICU stay, and the need for mechanical ventilation . K . pneumoniae or A . baumannii accounted for 57/158 (36%) of all ICU-acquired infections (in 46 patients) . They were considered as secondary endogenous infections (SEI) in 42 patients who were previously colonized with the same strains, and developed infection within a median of three days (range 0-68 days) . Prolonged stay in ICU was the only factor associated with SEI in the carrier population . Mortality was significantly greater in the carrier group (43 vs 25%, P = 0.0006) . Post hoc stratification suggested that abnormal carriage only influenced mortality in patients showing a low severity of illness score on admission to ICU . Abnormal carriage was found in the most severely ill patients, predisposed to secondary nosocomial infections, and could influence mortality in the less severely ill. J Bacteriol, 1996 Dec, 178(23), 6833 - 41 Novel nuclear magnetic resonance spectroscopy methods demonstrate preferential carbon source utilization by Acinetobacter calcoaceticus; Gaines GL 3rd et al.; Novel nuclear magnetic resonance spectroscopy techniques, designated metabolic observation, were used to study aromatic compound degradation by the soil bacterium Acinetobacter calcoaceticus . Bacteria which had been rendered spectroscopically invisible by growth with deuterated (2H) medium were used to inoculate cultures in which natural-abundance 1H hydrogen isotopes were provided solely by aromatic carbon sources in an otherwise 2H medium . Samples taken during the incubation of these cultures were analyzed by proton nuclear magnetic resonance spectroscopy, and proton signals were correlated with the corresponding aromatic compounds or their metabolic descendants . This approach allowed the identification and quantitation of metabolites which accumulated during growth . This in vivo metabolic monitoring facilitated studies of catabolism in the presence of multiple carbon sources, a topic about which relatively little is known . A . calcoaceticus initiates aromatic compound dissimilation by forming catechol or protocatechuate from a variety of substrates . Degradation proceeds via the beta-ketoadipate pathway, comprising two discrete branches that convert catechol or protocatechuate to tricarboxylic acid cycle intermediates . As shown below, when provided with several carbon sources simultaneously, all degraded via the beta-ketoadipate pathway, A . calcoaceticus preferentially degraded specific compounds . For example, benzoate, degraded via the catechol branch, was consumed in preference to p-hydroxybenzoate, degraded via the protocatechuate branch, when both compounds were present . To determine if this preference were governed by metabolites unique to catechol degradation, pathway mutants were constructed . Studies of these mutants indicated that the product of catechol ring cleavage, cis,cis-muconate, inhibited the utilization of p-hydroxybenzoate in the presence of benzoate . The accumulation of high levels of cis,cis-muconate also appeared to be toxic to the cells. Arch Biochem Biophys, 1996 Dec 1, 336(1), 42 - 8 Production, characterization, and reconstitution of recombinant quinoprotein glucose dehydrogenase (soluble type; EC 1.1.99.17) apoenzyme of Acinetobacter calcoaceticus; Olsthoorn AJ et al.; Soluble, periplasmic quinoprotein glucose dehydrogenase of Acinetobacter calcoaceticus (sGDH; EC 1.1.99.17) was produced in good yield in the apoenzyme form (without the cofactor pyrroloquinoline quinone, PQQ) by an Escherichia coli recombinant strain provided with a plasmid containing the gene under control of a lac promoter . Structural analysis of the purified apoenzyme revealed that the E . coli strain used produces the correct mature protein . Titration of the apoenzyme with PQQ in the presence of Ca2+ showed that a linear relation exists between the amount of added PQQ and activity observed, and that the subunit and PQQ associate in a molar ratio of 1:1 . Based on spectral and enzymatic criteria, it is concluded that the present holoenzyme preparation has a better quality than the previously described preparations of authentic holoenzyme . As isolated here, the recombinant apoenzyme was in the dimeric form . Partial monomerization occurred upon gel filtration in a buffer with chelator and the process could be reversed with Ca2+ . PQQ binds to the dimer in the presence of chelator, not to the monomer . However, the PQQ-containing dimer was not active and showed an unusual absorption spectrum which was slowly converted into a PQQH2-like spectrum when glucose was added . Full restoration of activity was achieved upon addition of Ca2+ and the spectra were immediately converted into those of normal holoenzyme in the oxidized and reduced form, respectively . Addition of chelator to holoenzyme did not lead to inactivation or monomerization . It is concluded, therefore, that Ca2+ has a dual role in this enzyme, being required for dimerization of the subunits as well as for functionalization of the bound PQQ, and that it is more firmly attached to the holoenzyme than to the apoenzyme. J Clin Microbiol, 1996 Dec, 34(12), 2894 - 6 Amplification and restriction endonuclease digestion of a large fragment of genes coding for rRNA as a rapid method for discrimination of closely related pathogenic bacteria; Ibrahim A et al.; By use of primers specific to conserved regions of the rRNA gene cluster, a discrete amplicon of approximately 5 kb was amplified by PCR from all 21 bacterial genera investigated . Subsequent endonuclease digestion of the PCR product with HaeIII distinguished between the three species of the human pathogen Francisella spp . on the one hand and four clinically relevant genomic groups of Acinetobacter spp . on the other hand . The described technique has the potential as a rapid method for discriminating between closely related species that are of clinical importance. J Clin Microbiol, 1996 Dec, 34(12), 2881 - 7 Influence of relative humidity and suspending menstrua on survival of Acinetobacter spp . on dry surfaces; Jawad A et al.; Acinetobacter spp . are being reported with increasing frequency as a cause of nosocomial infection and have been isolated from the skin of healthy individuals, patients, hospital staff, dry nonbiotic objects, and different pieces of medical equipment . Factors affecting the survival of Acinetobacter spp . under conditions closely similar to those found in the hospital environment were investigated in the present study to help us understand the epidemiology of nosocomial Acinetobacter infection . Bacterial cells were suspended in distilled water or bovine serum albumin and were dried onto glass coverslips and kept at different relative humidities . Cells washed from coverslips were used to determined viable counts . Freshly isolated strains of Acinetobacter spp . belonging to the clinically important Acinetobacter calcoaceticus-Acinetobacter baumannii complex were found to be more resistant to drying conditions (e.g., 30 days for A . baumannii 16/49) than American Type Culture Collection strains (e.g., 2 days for A . baumannii ATCC 9955) . The majority of strains belonging to the Acb complex had survival times similar to those observed for the gram-positive organism Staphylococcus aureus tested in the experiment . Survival times were prolonged for almost all the strains tested when they were suspended in bovine serum albumin (e.g., 60 days for A . baumannii R 447) compared with those for strains suspended in distilled water (11 days for R 447) . The survival times for strains at higher relative humidity (31 or 93%) were longer than those for strains of Acinetobacter kept at a relative humidity of 10% (11 days at 31% relative humidity and 4 days at 10% relative humidity for R447) . These findings are consistent with the observed tendency of Acinetobacter spp . to survive on dry surfaces, and they can be transferred not only by moist vectors but also under dry conditions in a hospital environment during nosocomial infection outbreaks . The results obtained in the experiment support the previously suggested airborne spread of Acinetobacter spp . in hospital wards and repeated outbreaks after incomplete disinfection of contaminated dry surfaces. J Infect Dis, 1996 Dec, 174(6), 1279 - 87 Investigation of a multiyear multiple critical care unit outbreak due to relatively drug-sensitive Acinetobacter baumannii: risk factors and attributable mortality; Kaul R et al.; From 1990 to 1993, an outbreak of respiratory Acinetobacter baumannii infection occurred in five intensive care units (ICUs) of a tertiary care center . A . baumannii was subsequently isolated from disinfected temperature probes and ventilator circuits . Pulsed-field gel electrophoresis suggested that a single strain accounted for 93% of patient isolates and 88% of environmental isolates . Univariate risk factors for A . baumannii acquisition were tracheostomy (P < .01), ventilation >3 days (P < .01), dialysis (P = .03), Stenotrophomonas maltophilia respiratory colonization (P = .02), parenteral nutrition (P = .05), and enteric feeding (P < .01) . Logistic regression analysis showed duration of ventilation and enteric feeding to be independent risk factors . The outbreak strain was relatively antibiotic-susceptible, but the mortality attributable to respiratory A . baumannii acquisition was 23% . Only the APACHE II score was independently associated with increased mortality . Multifaceted control measures, including gas sterilization of temperature probes, terminated the outbreak. Enferm Infecc Microbiol Clin, 1996 Nov, 14(9), 524 - 7 {Bactericide activity of sulbactam before bacteria belonging to the Acinetobacter calcoaceticus-Acinetobacter baumannii complex}; Villar HE et al.; BACKGROUND: To evaluate the bactericidal activity of colistin, imipenem and sulbactam against 24 Acinetobacter calcoaceticus-Acinetobacter baumannii complex isolations . METHODS: Bactericidal activity was estimated by using killing curves method . The concentrations employed were: colistin 4 mg/l, imipenem 8 mg/l and sulbactam 8 and 32 mg/l . RESULTS: Colistin was bactericidal in 24 isolations after 6 hours of incubation . When we used 8 mg/l of imipenem we detected bactericidal activity at the susceptible strains (MIC < or = 4 mg/l) . We found bactericidal effect in 15 of 18 strains susceptible to sulbactam when we used 8 mg/l in killing curves after 24 hours of incubation . Using 32 mg/l we detected the same effect in 18 strains with MIC < or = 8 mg/l . CONCLUSIONS: Considering the high incidence of resistance in Acinetobacter spp . to several antibiotics including imipenem, we consider that sulbactam could be an excellent therapeutic alternative because it presents bactericidal activity in susceptible strains. Pathology, 1996 Nov, 28(4), 359 - 63 Outbreak of gentamicin-resistant Acinetobacter baumanii in an intensive care unit: clinical, epidemiological and microbiological features; Riley TV et al.; The clinical, epidemiological and microbiological features of an outbreak of infection and colonisation caused by gentamicin-resistant Acinetobacter baumanii (GRAB) in an 18-bed intensive care unit (ICU) of a 680-bed adult teaching hospital are described . A retrospective review of medical, laboratory and infection control records was followed by prospective surveillance . Typing of isolates was performed by restriction enzyme analysis (REA) of chromosomal DNA . The incidence of GRAB in the ICU increased from 1.26 cases per 1000 occupied bed days (OBDs) for January to June 1993, to 6.62 per 1000 OBDs for July to December 1993 (Chi square = 4.8, P < 0.05), confirming the existence of an outbreak . For the two year period, 1993 and 1994, a total of 45 cases of GRAB infection or colonisation was identified . Males and females were equally represented, with an age range of 16-79 years and a mean age of 51 years . Admitting diagnoses varied, with multiple trauma and head injury predominating (ten cases) . For 35 of the 45 cases the initial site of GRAB isolation was sputum or other respiratory tract specimen . Specific treatment for GRAB was initiated in 23 patients, however no deaths were directly attributable to GRAB infection . The period of time between admission to the ICU and first isolation of GRAB ranged from three to 70 days with a median of nine days . Overall, ten (11%) of 91 staff hand samples and one of 37 (3%) environmental samples yielded GRAB . All GRAB isolates produced similar biochemical profiles and antibiotic resistance patterns, except for a group of five which were ciprofloxacin resistant . Thirty patient isolates, all ten staff hand isolates and the environmental isolate produced identical REA patterns . The remaining five patient isolates (all ciprofloxacin resistant) which were available for typing produced a different REA pattern . Our study has documented a moderate-sized outbreak of GRAB in an ICU setting . Typing of isolates using REA was useful in delineating outbreak strains . Carriage of GRAB on staff hands was demonstrated as the most likely source of infection . Despite institution of infection control measures GRAB now appears endemic in the ICU. Pathology, 1996 Nov, 28(4), 352 - 5 In vitro activity of meropenem compared to nine other antimicrobial agents: importance of its stability when used in agar dilution systems; Mudaliar UA et al.; The antibacterial activity of meropenem was tested against 426 clinical isolates representing a wide range of aerobic and anaerobic species . The in vitro activity of meropenem was compared with that of iminpenem, ceftazidime, cefotaxime, ciprofloxacin, piperacillin and tobramycin against aerobic isolates, and also compared with that of imipenem, metronidazole, cefoxitin, clindamycin and piperacillin against the anaerobic isolates . Meropenem exhibited an extended spectrum of activity with low minimal inhibitory concentrations (MIC) against Gram negative aerobes, anaerobes, Gram positive anaerobes and most of the Gram positive aerobes . The MIC90 of meropenem against the Enterobacteriaceae ranged from 0.03 mg/l to 0.125 mg/l . Meropenem was very active against extended spectrum beta lactamase producing Klebsiella pneumoniae, most Acinetobacter species, Pseudomonas aeruginosa, Clostridium difficile (MIC90 of 1.0 mg/l), Clostridium perfringens and other Clostridium species . Even though imipenem exhibited better activity against the coagulase negative staphylococci, meropenem still had MIC's which were less than the break point (8.0 mg/l) . The stability of meropenem in agar was determined indirectly by plotting the geometric mean MIC of control strains over a period of two weeks . Mean MIC of six control strains for meropenem was 0.05 mg/l and remained constant over 10 days, whereas the mean MIC of imipenem rose to 0.24 mg/l after two days and to 3.4 mg/l after 10 days . Meropenem was therefore far more stable in agar than imipenem . This has implications for laboratories using agar dilution as it requires less frequent plate preparation and decreased labour costs. Int J Clin Pharmacol Ther, 1996 Nov, 34(11), 465 - 9 Pharmacokinetics and bactericidal activity of a single daily dose of netilmicin in the treatment of CAPD-associated peritonitis; Anding K et al.; Single daily dosage of netilmicin is generally accepted in systemic infections, due to biphasic bactericidal activity and prolonged postantibiotic effect of aminoglycosides . Since little is known about the efficacy of single daily intraperitoneal application of netilmicin in the treatment of CAPD-associated peritonitis, we conducted this prospective study . Seven patients with CAPD-associated peritonitis were treated with a single daily dose of netilmicin (loading dose 1.5 mg/kg, followed by 40 mg/21 bag/day) . Serum and intraperitoneal levels as well as bactericidal activity of netilmicin against Acinetobacter baumanii, E . coli and Pseudomonas aeruginosa were measured for 48 hours . Serum and peritoneal levels widely varied among the patients due to different interindividual plasma clearance of netilmicin . The intraperitoneal antibacterial action of netilmicin was decreased, more over, substantial differences in the bactericidal activity were found among the patients . However, with high initial netilmicin levels sufficient bactericidal activity was found for Acinetobacter and E . coli, but not for Pseudomonas aeruginosa . Hence, a single daily dosage of netilmicin can be a suitable treatment of CAPD-associated peritonitis, only if the dose is adapted according to the first serum and peritoneal levels . In infections with Pseudomonas aeruginosa higher peritoneal levels of netilmicin and the combination with other antibiotics will be needed for a sufficient peritoneal bactericidal activity. J Biomed Mater Res, 1996 Nov, 32(3), 467 - 71 Endotoxin rejection by ultrafiltration through high-flux, hollow fiber filters; Yamamoto C et al.; The efficacy of endotoxin (ET) rejection of four hollow fiber membranes with comparable sieving properties was evaluated in an ultrafiltration experiment . The solution conditioned with type I lipopolysaccharide (LPS) from Escherichia coli, 80,000 endotoxin units (EU)/L, was filtered through polyesterpolymer alloy (PEPA), polymethyl methacrylate (PMMA), polyacrylonitrile (PAN), and polysulfone (PS) membranes . The ET activity of the filtrate was not detectable in PEPA and PMMA, 6.4 +/- .04 (mean +/- SD) EU/L in PAN, and 10.3 +/- 1.1 EU/L in PS . The ET activity of the filtrate of type II LPS from Acinetobacter solution, 80,000 EU/L, was not detectable in PEPA, 3.7 +/- 0.4 EU/L in PMMA, 16.5 +/- 1.5 EU/L in PAN, and 20.7 +/- 1.4 EU/L in the PS filter . The order of the rejection capability coincided with the adsorptive capacity as shown by the decrement in ET levels of solutions filled within the filter modules in the adsorption equilibrium experiment . In conclusion complete rejection of ET molecules can be achieved by ultrafiltration through hydrophobic membranes having a high adsorptive capacity in addition to an appropriate sieving property for ET molecules. Ugeskr Laeger, 1996 Oct 28, 158(44), 6260 - 2 {Microbiology of femoral head grafts in bone banks}; Husted H et al.; The aim of the study was to describe the bacteriology of bone allografts, which were harvested for the bone bank at Hvidovr Hospital, and to evaluate any infections in the recipients, which may have been caused by microbiological contamination of the transplanted bone allografts . It was carried out as a retrospective examination of bone bank records and patient records allowing at least 12 months for possible manifestation of bacterial infection by the bone allograft . During donation of bone, both the capita femora and the acetabulum were cultured with swabs both an- and aerobically along with the already sterilized glass specimen jar used for storage . Of the 110 donated bone allografts, 10 were not used for transplantation, but only one allograft was discarded because of the development of a positive culture (Staphylococcus epidermidis) . All cultures from the sterilized glass specimen jars were without microbiological growth . Three incidences of deep infection (one Acinetobacter calcoaceticus and two Staphylococcus aureus) followed the transplantation of 100 bone allografts in 58 patients at 62 operations . We conclude that the precautions (i.e . careful selection and screening of donor) and strict aseptic technique (including the use of perioperative administration of antibiotics) used, when bone allografts are harvested, ensure the procurement of non-contaminated bone in more than 99% of the donations . Culturing the already sterilized glass specimen jars seems unnecessary . The bone allograft per se was not contaminated and probably did not cause any infections . The rate of infection after transplantation of bone allograft is not higher than in other complicated surgery. Presse Med, 1996 Oct 12, 25(30), 1363 - 6 {Antibiotic sensitivity of aerobic gram-negative bacilli isolated from severe infections in 1992: results of a French multicenter study . Groupe d'Etude d'Infections à bacilles à Gram Négatif (GEIGN)}; Koeck JL et al.; OBJECTIVES: Antibiotic susceptibility of 649 gram-negative bacilli involved in severe infections and isolated in 18 teaching hospitals from January to December 1992 was evaluated . METHODS: Minimal Inhibitory Concentrations were determined by agar dilution method for piperacillin, piperacillin+ tazobactam and imipenem, and by a microdilution method for 11 other antibiotics (amoxicillin, amoxicillin + clavulanic acid, cefotaxime, ceftazidime, aztreonam, ticarcillin, ciprofloxacin, fosfomycin, tobramycin, gentamicin, amikacin) . Criteria of Comite Francais de l'Antibiogramme de la Societe Francaise de Microbiologie were followed for interpretation . Betalactamases were identified by isoelectric focusing and overproduction of cephalosporinase was defined by the resistance phenotype . The main species isolated were Escherichia coli (45%), Pseudomonas aeruginosa (14%), Klebsiella pneumoniae (7.8%), Salmonella spp . (7.5%), Enterobacter cloacae (4%) and Klebsiella oxytoca (4%) . Most of the strains were isolated from blood culture (72.3%), respiratory tract (11.4%) and intraabdominal infections (8.6%) . Most of the enterobacteria isolates were susceptible to imipenem, aztreonam, amikacin and ciprofloxacin (percentages of susceptibility were respectively 99.3, 98, 98.3 and 96.3); in most of cases clavulanic acid did not entirely restore sensitivity to amoxicillin of penicillinase-producing strains . Among 89 P . aeruginosa strains, 82% were susceptible to imipenem and ceftazidime, 81% to the association piperacillin + tazobactam and 51% to ticarcillin . Resistance rates are very high for Acinetobacter baumannii except for imipenem . CONCLUSION: Production of TEM-type penicillinase and over-production of the chromosomal cephalosporinase are the most widely observed mechanisms of resistance (respectively 22% and 9% of 649 strains) . Prevalence of extended spectrum betalactamases was low (1%) and essentially observed for K . pneumoniae. J Chemother, 1996 Oct, 8(5), 365 - 8 In vitro bactericidal effect of a beta-lactam+aminoglycoside combination against multiresistant Pseudomonas aeruginosa and Acinetobacter baumannii; Roussel-Delvallez M et al.; Pseudomonas aeruginosa and Acinetobacter baumannii are frequently isolated in hospital outbreaks of nosocomial infections . In our hospital, among 1018 strains isolated one year in an intensive care unit, 84 strains (8.3%) of P . aeruginosa and 155 strains (15.2%) of A . baumannii were considered responsible for infections . The major problem related to these bacteria is their multiresistant characteristic which confers great difficulty in treating infections . We carried out a 24 h time-kill study to assess the bactericidal effect of three beta-lactams {imipenem (IPM), ticarcillin+clavulanic acid (TCC), piperacillin+tazobactam (PTB)} in combination with each other and with sulbactam (SUL) and amikacin (AKN) against 8 P . aeruginosa strains and 8 A . baumannii strains . The initial inoculum was 10(6) cfu/ml . Antibiotics were tested at clinically achievable concentrations: TCC (112 mg/l), PTB (100 mg/l), IPM (25 mg/l) and AKN (15 mg/l) . The results showed: IMP + TCC + AKN = PTB + SUL + AKN = PTB + TCC + AKN > > IMP + SUL + AKN against P . aeruginosa; and PTB + SUL + AKN = PTB + TCC + AKN > IMP + SUL + AKN or IMP + TCC + AKN against A . baumannii . When infection due to these multiresistant strains was suspected, PTB + AKN combined with either TCC or SUL was bactericidal against both strains . These combinations appeared to be an alternative therapy in the treatment of undocumented nosocomial infections in intensive care units . These in vitro results are being evaluated in patients and seem to give good results for the moment. S Afr Med J, 1996 Oct, 86(10), 1276 - 80 Comparative in vitro activity of piperacillin/tazobactam against gram-negative bacilli; Liebowitz LD et al.; OBJECTIVE: To describe the in vitro activity of piperacillin/tazobactam against clinical isolates of Gram-negative bacteria, compared with other antibacterial agents . DESIGN: Survey of susceptibility of clinical isolates of Gram-negative bacilli . SETTING: Academic hospitals of the University isolates of the Witwatersrand teaching complex . BACTERIAL STRAINS: 180 selected clinical isolates of Gram-negative bacilli . MAIN OUTCOME MEASURES: Minimum inhibitory concentrations (MICs) determined by agar dilution using techniques according to the recommendations of the National Committee for Clinical Laboratory Standards . RESULTS: Ciprofloxacin, biapenerm, imipenem, cefepime and cefpirome were all highly active against most of the Enterobacteriaceae . All the ampicillin-resistant strains of Enterobacteriaceae were susceptible to piperacillin/tazobactam, MIC90 values being 4/4 mg/l for Klebsiella and Proteus/Providencia spp., 8/4 mg/l for Citrobacter and Serratia spp., and 16/4 mg/l for Escherichia coli . All the agents, with the exception of ampicillin (MIC90 4 mg/l) and chloramphenicol (MIC90 4 mg/l), were highly active against the Haemophilus influenzae isolates tested . All Bacteroides fragilis strains were susceptible to piperacillin/tazobactam (MIC90 8/4 mg/l), as well as to co-amoxiclav (MIC90 4/2 mg/l), biapenem and imipenem (MIC90s 0.5 mg/l) . The Pseudomonas spp . tested included strains resistant to piperacillin/tazobactam, ceftazidime, biapenem, gentamicin, tobramycin and ciprofloxacin . Cefepime was the most active agent against Pseudomonas isolates, with 90% of the strains being susceptible to this agent, while biapenem was the most active agent against the Acinetobacter isolates investigated . CONCLUSIONS: The in vitro spectrum of activity of piperacillin/tazobactam against the majority of isolates was comparable to those of the other new agents tested. Mol Microbiol, 1996 Oct, 22(2), 207 - 15 System to study horizontal gene exchange among microorganisms without cultivation of recipients; Stratz M et al.; Ribosomal RNA genes are characterized by highly conserved sequences and are present in multiple copies in most prokaryotic chromosomes . In principle, therefore, they might serve as sites for homologous recombination between unrelated microorganisms . Plasmids containing 23S ribosomal gene sequences, from different bacteria, which had been interrupted by insertion of a kanamycin-resistance gene, were used to transform Acinetobacter sp . DSM587 (former name: Acinetobacter calcoaceticus BD413-ivl10) . In all cases, homologies between the 23S rRNA genes of phylogenetically distant bacteria and Acinetobacter sp . DSM587 were sufficient for replacement recombination events . The integration events, resulting in inactivation of any one of the seven rrn operons of Acinetobacter sp . DSM587, had no observable influence on cell growth . These results suggest the possibility of rRNA genes serving as natural vehicles for horizontal gene transfer . They also provide the basis of a novel strategy to analyse gene transfer without selection or cultivation of recipient cells . Because of the highly conserved structure of bacterial rrn operons, recombination events subsequent to gene transfer can be readily identified by polymerase chain reaction amplification of the recombinant sequence using a universal forward primer for the 16S rRNA gene and a reverse primer specific for the integrated marker gene. Intensive Care Med, 1996 Oct, 22(10), 1057 - 65 Antibiotic susceptibility in aerobic gram-negative bacilli isolated in intensive care units in 39 French teaching hospitals (ICU study); Jarlier V et al.; OBJECTIVE: Evaluation of the distribution and antibiotic susceptibility of the aerobic gram-negative bacilli (AGNB) isolated from patients in intensive care units (ICU study) . DESIGN AND SETTING: Microbiological study carried out in 1991 in 39 teaching hospitals . A standardized method was used to determine the minimum inhibitory concentrations of 12 antibiotics against 3366 strains of AGNB (close to 100 strains per hospital) during a period of 3 months . RESULTS: The 2773 initial strains (i.e., the first AGNB isolate for a given species and a given patient) were mainly isolated from the respiratory tract (34.4%), urinary tract (23%), or blood (9.6%) and were mainly Pseudomonas aeruginosa (22.9%), Escherichia coli (22%), Acinetobacter (9.7%), and Klebsiella pneumoniae (8.3%) . E . coli was prominent in urine and blood and P . aeruginosa in the respiratory tract . Overall, the rate of susceptibility of AGNB was 58 to 65% to piperacillin, cefotaxime, and gentamicin; 69 to 75% to aztreonam, tobramycin, and ciprofloxacin; 83% to ceftazidime; and 91% to imipenem . The overall rates of susceptibility were higher for the initial strains isolated from blood than for those from the urinary or respiratory tracts, mostly reflecting differences in species distribution . Susceptibility rates were lower for the 593 repeat strains (i.e., all the subsequent isolates for a given species and a given patient) than for the initial strains, mostly due to the higher proportion of resistant species (P . aeruginosa 45.9%) but also due to the difference in susceptibility rates for some species-antibiotic combinations . Concomitant resistance (i.e., resistance to several antibiotics due to independent mechanisms of resistance) was marked between beta-lactams and aminoglycosides or quinolones, particularly in P . aeruginosa and K . pneumoniae . CONCLUSIONS: Rates of resistance in AGNB as a whole and in particular species (P . aeruginosa, Klebsiella), as well as frequency of concomitant resistance found in the French ICU study, were higher than those found in ICU studies conducted with the same methodology in Belgium, The Netherlands, and Germany, which may reflect differences in case mix. Biol Pharm Bull, 1996 Oct, 19(10), 1298 - 303 Occurrence of a novel L-2,4-diaminobutyrate decarboxylase activity in some species of Enterobacteriaceae, and purification and characterization of the enzymes of Enterobacter aerogenes and Serratia marcescens; Yamamoto S et al.; L-2,4-Diaminobutyrate decarboxylase (DABA DC) is a novel enzyme yielding 1,3-diaminopropane (DAP) from DABA, which has previously been purified from strains of the genera Vibrio and Acinetobacter . In this study, we also detected DABA DC activity in the species of Enterobacteriaceae: E . aerogenes, E . cloacae, E . agglomerans, Serratia marcescens, S . liquefaciens, Klebsiella pneumoniace, K . oxytoca and Citrobacter freundii, all of which produced DAP in sufficient amounts . Subsequently, the DABA DCs of E . aerogenes and S . marcescens were purified to homogeneity and characterized . Two separate enzymes had similar properties with respect to chromatographic behaviors, and were a dimer with subunits of identical molecular mass of about 51 kDa . The maximal activity of each enzyme was obtained at pH 8.0-8.25 . Both enzymes required pyridoxal 5'-phosphate and Mg2+ for full activity, and were highly specific for L-DABA . There was immunological similarity, but not identity between these proteins, as determined by Ouchterlony double diffusion analysis with antiserum against the E . aerogenes DABA DC . They showed the same N-terminal amino acid sequence up to the 8th residue (S-K-L-N-P-I-L-A-) . These enzymes were different in molecular mass, N-terminal amino acid sequence and antigenicity from DABA DCs of Acientobacter and Vibrio species. J Hosp Infect, 1996 Oct, 34(2), 139 - 44 The use of plasmid profile analysis and ribotyping for typing Acinetobacter baumannii isolates; Garcia DC et al.; Plasmid profiles were used to analyse 39 Acinetobacter baumannii isolates from 36 patients at three hospitals . The isolates were prevously classified by biotyping and rDNA fingerprinting . Ribotyping was useful to establish the lineage of isolates and to confirm genospecies identification . Thirty-seven isolates (94.9%) contained plasmids . The variable number of plasmids with different molecular weights in each isolate enabled the identification of 13 profiles without the need for endonuclease digestion . Fifteen A . baumannii biotype 2 isolates of similar ribotype and antibiotype contained identical plasmids over a two-month outbreak at one hospital . Plasmid typing discriminated these isolates from sporadic A . baumannii isolates of close ribotype obtained from different hospitals . A few isolates of different lineage, however, showed similar plasmid profile . Our results suggest that plasmid typing is a practical method to assist infection control of nosocomial A baumannii . A combination of plasmid typing and ribotyping is suggested to confirm genospecies classification and to identify strains against reference band profiles. Am J Infect Control, 1996 Oct, 24(5), 407 - 10 Use of sterile compared with tap water in gastrointestinal endoscopic procedures; Wilcox CM et al.; BACKGROUND: Because of the concern for infection risk, use of sterile water has been recommended in the water bottle for endoscopic equipment, although studies evaluating prevalence of contamination of the water bottle with clinical outcomes have not been performed . METHODS: Over a 12-week period in three endoscopy rooms at a university teaching hospital, the water bottles were filled on a weekly schedule with either sterile (one room) or tap water . The water bottles were sterilized on a weekly basis with an automated endoscope washer . At the end of each week, an aliquot of the remaining water was transferred to a sterile container, and quantitative cultures for aerobic and facultative anaerobic bacteria were performed by use of a 0.01 ml calibrated loop according to standard protocols . Cultures were performed in a blinded fashion without knowledge of the water source . Follow-up was performed on all patients within 2 weeks of the procedure to determine any potential infectious complications . RESULTS: During the study period, 437 procedures were performed (203 endoscopy, 68 colonoscopy, 38 sigmoidoscopy, 128 endoscopic retrograde cholangiopancreatography) . Of a total of 36 cultures (12 sterile), the results of nine (25%) were positive, including three bottles where sterile water was used . Bacterial isolates included five Flavobacterium sp., four Acinetobacter sp., two Pseudomonas sp., and one Stenotrophomonas maltophilia . Colony counts ranged from 900 to more than 10,000 per ml . On follow-up no patient had development of a clinical infection from any of these organisms . CONCLUSIONS: Bacterial growth in the water bottle was infrequent, consisted predominantly of nonpathogenic organisms, and was not associated with clinical complications . Our pilot study suggests that the use of tap water as compared with sterile water may be practical as well as provide cost savings. J Appl Bacteriol, 1996 Oct, 81(4), 355 - 62 Degradation of crude oil by Acinetobacter calcoaceticus and Alcaligenes odorans; Lal B et al.; Two types of Indian crude oil (Bombay High and Gujarat) were tested for their biodegradability by Acinetobacter calcoaceticus and Alcaligenes odorans . Acinetobacter calcoaceticus S30 and Alc . odorans P20 degraded Bombay High crude oil by 50% and 45%, while only 29% and 37% of Gujarat crude oil (heavy crude oil) was degraded by these isolates, respectively . Acinetobacter calcoaceticus and Alc . odorans in combination degraded 58% and 40% of Bombay High and Gujarat crude oils, respectively, which were significantly higher than that of by individual cultures . Acinetobacter calcoaceticus S30 degraded more of the alkanes fraction than the aromatics fraction of both crude oils . GC fingerprinting of alkane fraction showed major degradation of heptadecane (C17), octadecane (C18), nonadecane (C19), eicosane (C20), docosane (C22), tricosane (C23) and tetracosane (C24) of crude oil, while the Alc . odorans P20 degraded alkanes and aromatics equally . The asphaltenic component increased in both types of crude oil after biodegradation . The two strains grew very well on n-alkane up to C33 as well as on pristane (branched-chain alkane) but could not grow on cycloalkanes . Acinetobacter calcoaceticus S30 could not grow on pure polycyclic aromatic hydrocarbon (PAH) compounds except naphthalene but Alc . odorans P20 could grow on anthracene, phenanthrene, dibenzothiophene, fluorene, fluoranthene, pyrene and chrysene. J Clin Microbiol, 1996 Oct, 34(10), 2414 - 20 Acinetobacter species identification by using tRNA spacer fingerprinting; Ehrenstein B et al.; Identification of Acinetobacter spp . to the DNA group level by phenotypic techniques is problematic, and there is a need for an alternative identification method for routine use . The present study validated the suitability of a rapid identification technique based on tRNA spacer (tDNA) fingerprinting in comparison with that of a commercially available assay involving carbon source utilization tests (Biolog MicroStation System) for identifying the 21 DNA-DNA hybridization groups belonging to the genus . For this purpose, 128 strains identified previously by DNA-DNA hybridization were analyzed by both techniques . tDNA fingerprinting was highly reproducible and classified all strains into 17 groups . Six DNA groups belonging to the A . calcoaceticus-A . baumannii complex were grouped into two distinct clusters, indicating the high degree of genetic similarity within this complex . Strains of the more recently described DNA groups BJ13 to BJ16 were ambiguously grouped and displayed three pattern types . The software used with the commercial carbon source utilization method grouped the 128 strains into 12 clusters, explaining the less discriminatory power of this system . We conclude that tDNA fingerprinting offers a quick and reliable method for the routine differentiation of most Acinetobacter spp . at the subgenus level. J Bacteriol, 1996 Oct, 178(20), 6025 - 35 Physiological factors affecting production of extracellular lipase (LipA) in Acinetobacter calcoaceticus BD413: fatty acid repression of lipA expression and degradation of LipA; Kok RG et al.; The extracellular lipase (LipA) produced by Acinetobacter calcoaceticus BD413 is required for growth of the organism on triolein, since mutant strains that lack an active lipase fail to grow with triolein as the sole carbon source . Surprisingly, extracellular lipase activity and expression of the structural lipase gene (lipA), the latter measured through lacZ as a transcriptional reporter, are extremely low in triolein cultures of LipA+ strains . The explanation for this interesting paradox lies in the effect of fatty acids on the expression of lipA . We found that long-chain fatty acids, especially, strongly repress the expression of lipA, thereby negatively influencing the production of lipase . We propose the involvement of a fatty acyl-responsive DNA-binding protein in regulation of expression of the A . calcoaceticus lipBA operon . The potential biological significance of the observed physiological competition between expression and repression of lipA in the triolein medium is discussed . Activity of the extracellular lipase is also negatively affected by proteolytic degradation, as shown in in vitro stability experiments and by Western blotting (immunoblotting) of concentrated supernatants of stationary-phase cultures . In fact, the relatively high levels of extracellular lipase produced in the early stationary phase in media which contain hexadecane are due only to enhanced stability of the extracellular enzyme under those conditions . The rapid extracellular degradation of LipA of A . calcoaceticus BD413 by an endogenous protease is remarkable and suggests that proteolytic degradation of the enzyme is another important factor in regulating the level of active extracellular lipase. APMIS, 1996 Sep, 104(9), 659 - 65 Cell surface properties of Acinetobacter baumannii; Koljalg S et al.; Cell surface properties of 78 strains of Acinetobacter baumannii of different origin (lower respiratory tract, wound, blood and environment) were investigated . The bacterial adhesion to collagen, fibronectin, fibrinogen and vitronectin was detected by particle agglutination assays . Salt aggregation tests were used to determine the cell surface hydrophobicity of isolated A . baumannii strains . We found that A . baumannii strains originating from patients with wound infection and bacteraemia showed significantly lower aggregative properties compared to respiratory and environmental strains . Electron microscopic investigations revealed more fimbriated bacterial cells among the highly aggregative A . baumannii strains . This study demonstrates that the investigated A . baumannii strains can be divided into two different groups according to their cell surface properties and source of isolation, whereas the majority of strains, from the lower respiratory tract and the hospital environment expressed strong adhesive properties. Zentralbl Bakteriol, 1996 Sep, 285(1), 29 - 34 Phenotypic and genotypic characterization of clinically recovered presumptive Acinetobacter baumannii isolates which failed to grow at 44 degrees C; Traub WH et al.; Eleven clinical isolates of Acinetobacter, which exhibited an identical biochemical profile compatible with genospecies 3 and failed to grow at 44 degrees C, were not agglutinated by polyclonal rabbit immune sera against 26 serovars of genospecies 3 . Rather, all 11 isolates reacted strongly with antiserum against serovar 18 of A . baumannii . Macrorestriction (SmaI) analysis of genomic DNA revealed that only one isolate was genotypically different, whereas the remaining ones were either closely related or identical . However, the genomic DNA of the A . baumannii serovar 18 reference strain proved to be genotypically unrelated. Kansenshogaku Zasshi, 1996 Sep, 70(9), 938 - 46 {Simultaneous isolation of MRSA and Pseudomonas aeruginosa using a novel selective and differential PMAC agar}; Taguchi F et al.; PMAC agar, a novel, selective and differential medium has been developed and was subjected for evaluation of its selective and differential capability of methicillin resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa from other bacteria such as Bacillus, Micrococcus, Gram-negative bacteria and drug resistant ones . Growth of MRSA and P . aeruginosa on PMAC agar was facilitated and their colonies were easily differentiated . Colonies of MRSA after 24 approximately 48 h incubation at 35 degrees C were small (2 to 4 mm in diameter), smooth and egg-yolk reaction positive . On the other hand, P . aeruginosa with pigment production (pyocianin, fluorescin or pyomelanin) formed large (2.5 to 7.0 mm in diameter), brownish black or brown colonies with a creamy edge . PMAC agar did not allow to grow unwanted bacteria tested except certain species formerly classified to Pseudomonas such as Burkholderia and Stenotrophomonas . However multi-drug resistant strains such as Enterobacter cloacae, Serratia marcescens and Acinetobacter calcoaceticus formed extremely small colonies . PMAC agar is recommended as a novel, useful medium for isolation, differentiation and presumptive identification of MRSA and P . aeruginosa from clinical and environmental sources. Cent Eur J Public Health, 1996 Sep, 4(3), 197 - 200 Behaviour of Acinetobacter strains with normal human serum; Cervi BM et al.; The bactericidal activity of normal human serum (NHS) and treated NHS to avoid either the classical complement pathway (CPC) or the alternative complement pathway (APC) was studied with four strains identified as Acinetobacter baumanii . Three of them were sensitive to serum whereas only one was serum resistant . The serum sensitive strains showed different susceptibility mechanisms: one strain was sensitive to both the CPC and the APC and the others were sensitive only to APC . Serum sensitive and serum resistant strains showed on PAGE-SDS and silver strain incomplete profiles of lipopolysaccharides (LPS) . In all cases the carbohydrate percentage of LPS was lower than the value corresponding to Salmonella enteritidis with complete profiles of LPS . The strain sensitive to CPC and APC had a lower carbohydrate content . The serum sensitivity of the three strains could be attributed to the presence of incomplete LPS, while the serum resistance could be assigned either to small variations in the LPS composition or to some particular membrane component. Clin Infect Dis, 1996 Sep, 23(3), 631 - 4 Use of macrorestriction analysis to demonstrate interhospital spread of multiresistant Acinetobacter baumannii in São Paulo, Brazil; Sader HS et al.; We evaluated the spread of Acinetobacter baumannii strains among three hospitals located in Sao Paulo, Brazil . A total of 46 isolates, which were typed by chromosomal DNA analysis with use of pulsed field gel electrophoresis (PFGE), were tested for susceptibility to the fluoroquinolones, carbapenems, aminoglycosides (amikacin), cephalosporins, polymyxin B, and ampicillin/sulbactam by means of the broth microdilution method, disk diffusion, and the E-test . Isolates with an identical PFGE pattern (pattern B) that were susceptible only to carbapenems, polymyxin B, and ampicillin/ sulbactam were recovered in all three hospitals . In addition, isolates with PFGE pattern A that were susceptible only to polymyxin B and ampicillin/sulbactam were recovered in hospitals 1 and 2 . The results of our study strongly suggest the interhospital transmission of multiresistant epidemic strains of A . baumannii in Sao Paulo . Once in the hospital, these strains can disseminate and cause outbreaks with devastating consequences. Clin Infect Dis, 1996 Sep, 23(3), 538 - 42 Mortality due to ventilator-associated pneumonia or colonization with Pseudomonas or Acinetobacter species: assessment by quantitative culture of samples obtained by a protected specimen brush; Fagon JY et al.; Ventilator-associated pneumonia (VAP) due to multiresistant pathogens is associated with a high death rate . We analyzed the relationship between VAP due to Pseudomonas or Acinetobacter species and death by comparing the outcomes for patients colonized with these pathogens (bacterial counts of < 10(3) cfu/mL) with those for patients with pneumonia due to these pathogens (bacterial counts of > or = 10(3) cfu/mL) . Samples were obtained systematically with a protected specimen brush when pneumonia was suspected . Clinical characteristics at admission to our intensive care unit and clinical features at the time of suspicion of VAP were not significantly different between colonized patients and those with VAP . Mortality rates were 29% among colonized patients and 73% among patients with VAP (P < .001) . These results demonstrate a relationship between a high mortality rate and the development of pneumonia due to multiresistant, nonfermenting, gram-negative bacilli ( > or = 10(3) cfu/mL) in the lower airways of patients receiving ventilatory support. Chemotherapy, 1996 Sep-Oct, 42(5), 334 - 42 Susceptibility of clinical isolates to expanded-spectrum beta-lactams alone and in the presence of beta-lactamase inhibitors; Qadri SM et al.; Tazobactam and BRL 42715 are relatively new penems which inhibit a wide range of plasmid- as well as chromosomally mediated bacterial beta-lactamases that include Richmond and Sykes type I, II, III, IV and V beta-lactamases, staphylococcal penicillins and extended-spectrum beta-lactamases . However, clavulanic acid, which is a potent inhibitor of class III beta-lactamases, is one of the first discovered compounds . We used a total of 645 recent clinical isolates, consisting of 305 Enterobacteriaceae, 180 gram-positive cocci and 160 other gram-negative bacteria to evaluate the ability of beta-lactamase inhibitors for potentiation of piperacillin, ticarcillin and amoxycillin . Minimum inhibitory concentrations for all the 42 strains of methicillin-susceptible Staphylococcus aureus were reduced 4- to 16-fold in the presence of beta-lactamase inhibitors . They were also highly effective in inhibiting the beta-lactamase of a wide variety of gram-negative bacteria, thereby changing their MIC values for amoxycillin, ticarcillin and piperacillin from a 'resistant' to a 'susceptible' range . Commonly resistant bacteria like Klebsiella, Enterobacter, Serratia, Acinetobacter and Pseudomonas were rendered susceptible to piperacillin and ticarcillin in the presence of clavulanic acid, tazobactam and BRL 42715 . Of the commercially available formulations for clinical use, piperacillin/tazobactam (Tazocin) was found to be more inhibitory towards both gram-positive and gram-negative bacteria. FEMS Microbiol Lett, 1996 Sep 1, 142(2-3), 191 - 4 High resolution DNA fingerprinting of Acinetobacter outbreak strains; Janssen P et al.; AFLP is a novel high resolution fingerprinting method that can be used to delineate intraspecific relationships among a large variety of organisms, including bacteria . In the present study, this method was tested for its usefulness in the epidemiological typing of Acinetobacter strains . A total of 25 Acinetobacter strains originating from five hospital outbreaks in three countries were used . Isolates from the same outbreak displayed identical banding patterns and each set of outbreak strains could be found in one particular AFLP cluster . These data are in good agreement with the results obtained by other typing methods previously used on the same set of strains, indicating that AFLP analysis may be a valuable alternative in epidemiological typing. J Biotechnol, 1996 Aug 20, 49(1-3), 239 - 43 Increased production of recombinant pyrroloquinoline quinone (PQQ) glucose dehydrogenase by metabolically engineered Escherichia coli strain capable of PQQ biosynthesis; Sode K et al.; We have previously shown that the production of recombinant Escherichia coli PQQGDH was greatly improved by using a medium supplemented with the cofactor PQQ, which is not synthesized in E . coli . We show here that the increase in the accumulated PQQGDH is due to the increased stability of the holo-enzyme over apo-enzyme, using recombinant Acinetobacter calcoaceticus PQQGDH . In order to achieve cost-effective PQQGDH production, we incorporated the genes for PQQ biosynthetic pathway from Klebsiella pneumoniae into E . coli, which as a result allowed E . coli to produce PQQ . Using this metabolically engineered E . coli strain as a host, a 10-fold increase in the production of recombinant A . calcoaceticus PQQGDH was achieved, compared to the condition without PQQ and MgCl2. Biokhimiia, 1996 Aug, 61(8), 1471 - 82 {Novel site-specific endonuclease from Acinetobacter species M strain}; Zelinskaia NV et al.; Site-specific endonuclease R.AspMI was isolated and purified to apparent functional homogeneity from Acinetobacter species (strain M) . The enzyme recognizes symmetrical DNA sequence 5'-AGG decreases CCT-3' and cleaves it at the site indicated by the arrow forming blind DNA ends . The endonuclease is an isoschizomer of the StuI endonuclease . Cleavage of the DNA site was inhibited by dcm-methylation . AspMI is approximately equal to 30 kD monomer. Zentralbl Bakteriol, 1996 Aug, 284(4), 550 - 8 Biotypes, serovars and antimicrobial resistance patterns of Acinetobacter baumannii clinical isolates; Oliveira MG et al.; 255 Acinetobacter strains, from clinical specimens of inpatients and outpatients, were identified phenotypically according to the new taxonomy proposed by Bouvet and Grimont . A . baumannii was the most frequent species (80.8%) . This species underwent biotyping and serotyping according to the scheme of Bouvet and Grimont, and that of Traub, respectively, 81.2% of samples belonged to biotypes 2, 6 and 9 with a predominance of biotype 2 . 86.6% of the strains could be serotyped; 2 new serotypes were encountered . The new serotype 29, being the most frequently isolated, was related to biotype 2 (86.6%), whereas serotype 13 was related to biotype 6 (84.8%) . These clones presented marked multiple resistance patterns and were widespread in different wards . No outbreak was reported during the period studied . These phenotypical methods proved to be useful in differentiating strains of A . baumannii and, if used together, they showed a high discriminatory power. Kansenshogaku Zasshi, 1996 Aug, 70(8), 775 - 83 {Study on septicaemia in infants and children in the past 20 years . Part 1 . An analysis of causal organisms}; Sato T et al.; Causal organisms and their changes were evaluated in 158 cases of septicaemia admitted to Jikei University Hospital from 1975 to 1994 . Eighty patients (50.6%) were aged less than 1 year, and 37 patients (23.4%) were newborns . The average mortality rate was 18.4% . The mortality rate between 1975 and 1984 was 26.8%, and that of the past 10 years (from 1985 to 1994) decreased to 13.7% . Staphylococcus aureus (29 cases, 19.4%) was the most common pathogens isolated, followed by Pseudomonas sp . (24 cases, 15.2%), Escherichia coli (19 cases, 12.0%), and Haemophilus influenzae (18 cases, 11.4%) . H . influenzae, Acinetobacter sp., Streptococcus pneumoniae and Group B streptococcus (GBS) increased in the past 10 years (from 1985 to 1994), compared with the preceding 10 years (from 1975 to 1984) . The mortality rate of Klebsiella sp . septicaemia (28.6%) was highest, followed by Pseudomonas sp . (25.0%), S . aureus (24.1%), S . pneumoniae (22.2%) . H . influenzae and Acinetobacter sp . septicaemia were not fatal . E . coli and GBS were common among neonates and patients aged less than 1 year . H . influenzae septicaemia occurred mainly in patients with meningitis, in those younger than school age . Acinetobacter sp . was common among neonates and children with leukaemia Pseudomonas sp., Klebsiella sp., and Acinetobacter sp . were mainly detected in patients with underlying diseases . E . coli, H . influenzae, S . pneumoniae and GBS were mainly detected in patients without underlying diseases. J Antimicrob Chemother, 1996 Aug, 38(2), 245 - 51 Imipenem resistance among Acinetobacter baumannii: association with reduced expression of a 33-36 kDa outer membrane protein; Clark RB; The mechanism of imipenem resistance of two Acinetobacter baumannii isolates (A-1 and A-24) was characterized in this study . A spontaneous revertant (A-1 (rev)) derived from isolate A-1 showed susceptibility to imipenem . beta-Lactamase hydrolysis studies showed no evidence of an imipenem hydrolyzing enzyme among A-1, A-24, A-1 (rev), or two other imipenem susceptible A . baumannii isolates . Outer membrane protein (OMP) analysis indicated decreased expression of a 33-36 kDa protein by isolates A-1 and A-24 when compared with A-1 (rev) and the other A . baumannii isolates . In conclusion, decreased expression of a 33-36 kDa OMP is associated with imipenem resistance among A . baumannii. Cardiovasc Surg, 1996 Aug, 4(4), 476 - 9 Surgical treatment of infected thoracic and abdominal aortic aneurysms; Chiba Y et al.; Twelve patients with infected aneurysms of the thoracic and abdominal aorta were evaluated . Aneurysmal location, aetiology, bacteriology and treatment modality were analysed to determine the relationship between these factors and outcome . Patients were divided into two groups based on the preoperative states of their infections . Group 1 patients (n = 7) underwent resection after resolution of their active infection . The causative organisms included Staphylococcus epidermidis (two cases) . Salmonella spp . (one) . Acinetobacter (one), Mycobacterium tuberculosis (one) and unknown organisms (two) . Group 2 patients (n = 5) required urgent surgery because of uncontrolled sepsis despite intensive treatment with antibiotics . The causative organisms included Staphylococcus aureus (two cases) . Pseudomonas aeruginosa (two) and Salmonella spp . (one) . In group 1, three patients underwent closed en bloc excision of the aneurysm with in-situ graft replacement, and four underwent partial resection with in-situ graft replacement . In group 2, three patients underwent resection of the aneurysm with ligation of aorta and extra-anatomic bypass, and two underwent in-situ graft replacement after debridement of infected tissue . Overall, patients in group 1 had a mortality rate of 14% compared with 80% in group 2 . These results suggest that the operative approach and method chosen to restore arterial continuity have less of an impact on outcome . The primary determinants of outcome are virulence of the infecting organism and the preoperative state of the infection. New Horiz, 1996 Aug, 4(3), 321 - 32 Mechanisms of bacterial antibiotic resistance; Jenkins SG; Infectious complications are major contributing factors to morbidity and mortality in the ICU setting . Organisms frequently encountered in the ICU include Pseudomonas aeruginosa, Staphylococcus aureus, Haemophilus influenzae (particularly in trauma victims), enterococci, Klebsiella pneumoniae, Enterobacter spp., Acinetobacter baumanii, Escherichia coli, and Stenotrophomonas (Xanthomonas) maltophilia . Antibiotics have played a major role in the treatment of infections caused by such bacterial pathogens . Organisms have responded to the antibiotic challenge, however, evolving and developing resistance to all available antimicrobial agents to a greater or lesser degree . Specific mechanisms of resistance include reductions in cell-wall membrane permeability, alterations of antimicrobial agent target sites, enzymatic inactivation of antibiotics, and development of bypass pathways around antimicrobial targets . This article describes, pathogen by pathogen, antimicrobial agents that are useful for the treatment of infection in the ICU setting and the mechanisms whereby bacteria have short-circuited our antimicrobial armamentarium. Eur J Biochem, 1996 Aug 1, 239(3), 602 - 10 Structural and serological characterisation of two O-specific polysaccharides of Acinetobacter; Vinogradov EV et al.; Extraction of dry bacteria of Acinetobacter strain 34 (DNA group 2) or Acinetobacter strain 108 (DNA group 13) by phenol/water yielded a polymer that was identified by means of serological studies and fatty acid analysis as S-form lipopolysaccharide . Degradation of the lipopolysaccharides of strains 34 and 108 in 1% acetic acid and 5% acetic acid, respectively, and gel-permeation chromatography gave the respective O-antigenic polysaccharides, the structures of which were determined, by compositional analysis and NMR spectroscopy of the polysaccharide, as {Sequence: see text} for strain 108, where D-Fucp3NBuOH represents 3-{(R)-3-hydroxybutyramido} -3,6-dideoxy-D-galactose and D-GalpANAc represents 2-acetamido-2-deoxy-D-galacturonic acid . Both structures were specifically recognised in Western blots by polyclonal rabbit antisera and there was no cross-reaction between these two structures. Arch Microbiol, 1996 Aug, 166(2), 128 - 31 Sequence analysis of the gene encoding a novel L-2,4-diaminobutyrate decarboxylase of Acinetobacter baumannii: similarity to the group II amino acid decarboxylases; Ikai H et al.; The gene (ddc) encoding a novel enzyme, l-2,4-diaminobutyrate decarboxylase (DABA-DC; EC 4.1.1.-) in Acinetobacter baumannii was sequenced, and an open reading frame of 1,530 nucleotides was detected . The sequence of 20 N-terminal amino acids of purified DABA-DC and of its proteolytic peptide fragments coincided with those deduced from the nucleotide sequence determined . Comparison of the predicted amino acid sequence of the A . baumannii enzyme with those of other pyridoxal 5'-phosphate-dependent decarboxylases revealed significant similarity to the group II amino acid decarboxylases and conservation of the putative pyridoxal 5'-phosphate-binding domain. Rev Argent Microbiol, 1996 Jul-Sep, 28(3), 143 - 6 {Cross-reactivity between Chlamydia psittaci and Acinetobacter in indirect immunofluorescence assays}; Espinosa M et al.; Cross reactivity between Chlamydia psittaci and a strain from genus Acinetobacter was investigated by indirect fluorescent antibody (IFA) technique . Two groups of serum samples were tested: 64 belonged to patients diagnosed as psittacosis and 64 (control group) were non reactive to Chlamydia psittaci by IFA . Samples were incubated on smears prepared with an Acinetobacter suspension for detecting IgG and IgM . 100% reactivity to IgG was found in 1:16 serum dilution among anti-psittacosis sera, whereas 6.25% of control sera reacted at the same dilution . When testing IgM, high rates of reactivity were found in both serum groups, thus it has been discarded as a marker for cross reactivity . Fluorescence pattern suggests that antigens are located at the cell wall. Eur J Clin Microbiol Infect Dis, 1996 Jul, 15(7), 533 - 44 Sinusitis in mechanically ventilated patients and its role in the pathogenesis of nosocomial pneumonia; Bert F et al.; Nosocomial sinusitis is a complication of endotracheal intubation and mechanical ventilation in critically ill patients . Its incidence is often underestimated because of a lack of clinical signs . It is suspected in patients with nasal discharge or unexplained fever . Its diagnosis is based on radiological examination, by radiograph or computed tomography scan, and microbiological cultures of maxillary sinus aspirate . Maxillary sinusitis is often associated with involvement of the sphenoid, ethmoid, and/or frontal sinuses . Its incidence varies greatly according to diagnostic criteria and the population studied . Infectious sinusitis is less frequent than noninfectious sinusitis, occurring in 20 to 30% of patients intubated for at least seven days . Its incidence is higher in nasotracheally than in orotracheally intubated patients . Other risk factors include nasogastric tubes and head trauma . The main causative agents are gram-negative bacilli, primarily Pseudomonas aeruginosa, Acinetobacter baumannii, and Enterobacteriaceae, but Staphylococcus aureus and yeasts are also common . Patients with nosocomial sinusitis are more likely to develop pneumonia than those without sinusitis . The sinus provides a bacterial reservoir from which organisms may seed the tracheobronchial tree . The association of sinusitis and pneumonia is mainly due to Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii . The treatment of sinusitis is based on the removal of all nasal tubes, topical decongestants, and maxillary sinus drainage and lavage . The role of intravenous antibiotics is controversial. Microbiology, 1996 Jul, 142 ( Pt 7), 1881 - 93 Evaluation of the DNA fingerprinting method AFLP as an new tool in bacterial taxonomy; Janssen P et al.; We investigated the usefulness of a novel DNA fingerprinting technique, AFLP, which is based on the selective amplification of genomic restriction fragments by PCR, to differentiate bacterial strains at the subgeneric level . In totals, 147 bacterial strains were subjected to AFLP fingerprinting: 36 Xanthomonas strains, including 23 pathovars of Xanthomonas axonopodis and six pathovars of Xanthomonas vasicola, one strain of Stenotrophomonas, 90 genotypically characterized strains comprising all 14 hybridization groups currently described in the genus Aeromonas, and four strains of each of the genera Clostridium, Bacillus, Acinetobacter, Pseudomonas and Vibrio . Depending on the genus, total genomic DNA of each bacterium was digested with a particular combination of two restriction endonucleases and the resulting fragments were ligated to restriction halfsite-specific adaptors . These adaptors served as primer-binding sites allowing the fragments to be amplified by selective PCR primers that extend beyond the adaptor and restriction site sequences . Following electrophoretic separation on 5% (w/v) polyacrylamide/8.3 M urea, amplified products could be visualized by autoradiography because one of the selective primers was radioactively labelled . The resulting banding patterns, containing approximately 30-50 visualized PCR products in the size range 80-550 bp, were captured by a high-resolution densitoscanner and further processed for computer-assisted analysis to determine band-based similarity coefficients . This study reveals extensive evidence for the applicability of AFLP in bacterial taxonomy through comparison of the newly obtained data with results previously obtained by well-established genotypic and chemotaxonomic methods such as DNA-DNA hybridization and cellular fatty acid analysis . In addition, this study clearly demonstrates the superior discriminative power of AFLP towards the differentiation of highly related bacterial strains that belong to the same species or even biovar (i.e . to characterize strains at the infrasubspecific level), highlighting the potential of this novel fingerprinting method in epidemiological and evolutionary studies. Microbiology, 1996 Jul, 142 ( Pt 7), 1873 - 9 A reappraisal of the diversity and class distribution of aspartate transcarbamoylases in gram-negative bacteria; Kenny MJ et al.; Recently, the subunit composition of class A aspartate transcarbamoylases (ATCases) in fluorescent pseudomonads has been clarified . We present evidence that distribution of this type of ATCase may be more widespread than at first suspected . Bacterial ATCases exist in three forms: class A (molecular mass approximately 450-500 kDA); class B, typified by Escherichia coli ATCase (approximately 300 kDa); and class C, typified by Bacillus subtilis ATCase (approximately 100 kDa) . Using gradient gel electrophoresis with activity-staining to scan bacterial sonicates, we report the existence of six more class ATCases . We have purified one of these, Acinetobacter calcoaceticus ATACase, and found its subunit composition to be similar to that of the pseudomonad ATCases . Two of these ATCases come from bacteria outside the gamma-subgroup of the Proteobacteria, one from the alpha-subgroup and one from Deinococcus radiophilus, a species phylogenetically remote from the Proteobacteria . Unexpectedly, three bacterial species, closely related to the fluorescent pseudomonads and acinetobacters, have ATCases of 100 kDa (class C) . One of these, Stenotrophomonas (formerly Xanthomonas) maltophilia has been purified and found to be a homotrimer of 35 kDa polypeptide chains . We believe this is the first time that class C ATCases have been reported in Gram-negative bacteria . A distinctive cluster in the gamma-3 subgroup of the Proteobacteria is formed by the enteric bacteria and their relatives . So far only class B ATCases have been reported in this group . The evolutionary implications of these findings are discussed. Microbiology, 1996 Jul, 142 ( Pt 7), 1825 - 31 IS1236, a newly discovered member of the IS3 family, exhibits varied patterns of insertion into the Acinetobacter calcoaceticus chromosome; Gerischer U et al.; Analysis of spontaneous mutations in Acinetobacter calcoaceticus revealed a 1237 bp insertion sequence named IS1236 and possessing a nucleotide sequence resembling those of members of the lS3 family . The chromosome of A . calcoaceticus strain ADP1 contains seven copies of IS1236 which appears to insert preferentially into pobR, the transcriptional activator of the structural gene for p-hydroxybenzoate hydroxylase . IS1236 creates tandem 3 bp DNA duplications flanking the sites of its insertion in pobR . Different duplication patterns are found following insertion of IS1236 into pcaH, a structural gene for protocatechuate 3,4-dioxygenase . Therefore the insertion of properties of IS1236 appear to be influenced by its DNA target . Amino acid sequences associated with the apparent transposase function have been conserved in ORFB of IS1236 whereas the presumed DNA-binding helix-turn-helix region of IS1236 ORFA exhibits substantial amino acid sequence divergence from its IS3 counterparts . IS1236 ORFA and ORFB coding sequences overlap considerably, and sequence evidence indicates mechanisms for ORFB expression in IS1236 may resemble those employed by other members of the IS3 family . Portions of the IS1236 terminal repeats exhibit substantial sequence divergence from other members of the IS3 family, but evolution appears to have conserved a mechanism preventing expression of the insertion sequence genes as a consequence of transcriptional readthrough. J Bacteriol, 1996 Jul, 178(13), 3695 - 700 Isolation and characterization of a novel oxygenase that catalyzes the first step of n-alkane oxidation in Acinetobacter sp . strain M-1; Maeng JH et al.; In the Finnerty pathway for n-alkane, oxidation in Acinetobacter sp., n-alkanes are postulated to be attacked by a dioxygenase and the product, n-alkyl hydroperoxide, is further metabolized to the corresponding aldehyde via the peroxy acid {W . R . Finnerty, P . 184-188, in A . H . Applewhite (ed.), Proceedings of the World Conference on Biotechnology for the Fats and Oil Industry, 1988} . However, no biochemical evidence regarding the first-step reaction is available . In this study, we found a novel n-alkane-oxidizing enzyme that requires only molecular oxygen, i.e., not NAD(P)H, in our isolate, Acinetobacter sp . strain M-1, and purified it to apparent homogeneity by gel electrophoresis . The purified enzyme is a homodimeric protein with a molecular mass of 134 kDa, contains 1 mol of flavin adenine dinucleotide per mol of subunit, and requires CU2+ for its activity . The enzyme uses n-alkanes ranging in length from 10 to 30 carbon atoms and is also active toward n-alkenes (C12 to C20) and some aromatic compounds with substituted alkyl groups but not toward a branched alkane, alcohol, or aldehyde . Transient accumulation of n-alkyl hydroperoxide was detected in the course of the reaction, and no oxygen radical scavengers affected the enzyme activity . From these properties, the enzyme is most probably a dioxygenase that catalyzes the introduction of two atoms of oxygen to the substrate, leading to the formation of the corresponding n-alkyl hydroperoxide . The enzymatic evidence strongly supports the existence of an n-alkane oxidation pathway, which is initiated by a dioxygenase reaction, in Acinetobacter spp. J Mol Biol, 1996 Jun 28, 259(5), 891 - 5 Autophosphorylation of a bacterial protein at tyrosine; Duclos B et al.; Autophosphorylation at tyrosine is a common process in eukaryotic kinases, which is generally modulated by regulatory ligands and affects the properties of these enzymes . We report that this type of modification occurs also in bacteria, namely in an 81 kDa protein from Acinetobacter johnsonii . This protein is phosphorylated at the expense of ATP exclusively at tyrosine residues . It is located in the inner-membrane fraction of cells and can be totally solubilized by detergents . It has been purified to homogeneity by antiphosphotyrosine immunochromatography . Analysis of the peptides released under trypsin proteolysis of the protein has shown that it autophosphorylates at several tyrosine residues . The discovery of protein autophosphorylation in bacteria seems of special interest for studying the regulatory aspects of this modification when considering the relative simplicity of the bacterial systems, as compared with most eukaryotic systems, namely in terms of physiology and genetics. J Ind Microbiol, 1996 Jun, 16(6), 364 - 9 Biomass relationship to growth and phosphate uptake of Pseudomonas fluorescens, Escherichia coli and Acinetobacter radioresistens in mixed liquor medium; Momba MN et al.; The ability of Pseudomonas fluorescens, Escherichia coli and Acinetobacter radioresistens to remove phosphate during growth was related to the initial biomass as well as to growth stages and bacterial species . Phosphate was removed by these bacteria under favourable conditions as well as under unfavourable conditions of growth . Experiments showed a relationship between a high initial cell density and phosphate uptake . More phosphate was released than removed when low initial cell densities (10(2)-10(5) cells ml-1) were used . At a high initial biomass concentration (10(8) cells ml-1), phosphate was removed during the lag phase and during logarithmic growth by P . fluorescens . Escherichia coli, at high initial biomass concentrations (10(7) cells ml-1), accumulated most of the phosphate during the first hour of the lag phase and/or during logarithmic growth and in some cases removed a small quantity of phosphate during the stationary growth phase . Acinetobacter radioresistens, at high initial cell densities (10(6), 10(7) cells ml-1) removed most of phosphate during the first hour of the lag phase and some phosphate during the stationary growth phase . Pseudomonas fluorescens removed phosphate more than A . radioresistens and E . coli with specific average ranges from 3.00-28.50 mg L-1 compared to average ranges of 4.92-17.14 mg L-1 for A . radioresistens and to average ranges of 0.50-8.50 mg L-1 for E . coli. Diagn Microbiol Infect Dis, 1996 Jun, 25(2), 53 - 64 Sparfloxacin worldwide in vitro literature: isolate data available through 1994; Cohen MA et al.; Sparfloxacin is a piperazinyl, cyclopropyl-fluoroquinolone with broad-spectrum antibacterial activity . Compared to other quinolones, sparfloxacin displays improved activity against a variety of pathogens including Staphylococcus, Streptococcus, Enterococcus, Chlamydia, Mycoplasma, Ureaplasma, and Mycobacteria species . Other susceptible organism group include Haemophilus, Legionella, Moraxella, Neisseria, Aeromonas, Acinetobacter, Bordetella, Brucella, Campylobacter, Gardnerella, and Helicobacter species . Most Enterobacteriaceae are also susceptible, whereas most isolates of Pseudomonas aeruginosa are not . Sparfloxacin is bactericidal . Activity is generally stable to variations of inoculum, pH, and cation concentration, and it is unchanged in the presence of 5% sodium cholate or 70% human serum . Susceptibility to the drug is diminished in urine . Cross-resistance, although incomplete, has been documented with other quinolones, but not with other antimicrobic classes. Eur J Clin Microbiol Infect Dis, 1996 Jun, 15(6), 512 - 5 Emergence of resistant isolates of Acinetobacter calcoaceticus- A . baumannii complex in a Spanish hospital over a five-year period; Garcia-Arata MI et al.; Acinetobacter calcoaceticus-A . baumannii complex species have emerged as a relevant cause of nosocomial infection and colonization over the past 20 years, mainly in intensive care units . The aim of this study was to investigate the in vitro activity of 14 antimicrobial agents against 177 clinical isolates from patients admitted to a Spanish teaching hospital over a five-year period . Susceptibility rates or 99%, 99%, and 74% were obtained for imipenem, meropenem, ampicillin plus sulbactam, and amikacin, respectively . Increases in resistance were detected mainly for ticarcillin, piperacillin plus tazobactam, ceftazidime, amikacin, and ofloxacin . These results indicate that treatment of nosocomial infections due to Acinetobacter calcoaceticus-A . baumannii complex strains may be difficult. Zentralbl Bakteriol, 1996 Jun, 284(1), 115 - 23 Clusters of nosocomial cross-infection due to Acinetobacter baumannii and genospecies 3: comparison of serotyping with macrorestriction analysis of genomic DNA with pulsed-field gel electrophoresis; Traub WH et al.; Triplets of isolates representing 20 putative clusters of nosocomial cross-infection due to Acinetobacter baumannii and genospecies 3 were examined comparatively using serotyping and analysis of restriction fragments (SmaI and ApaI) of genomic DNA with the aid of pulsed-field gel electrophoresis . Carbon source assimilation tests disclosed phenotypic variation among 6 to 20 triplets of isolates . Two misleading results of serotyping were encountered . With respect to the presumptive cluster No . 9, one of the genospecies 3 (originally serovar 4) isolates proved to be polyagglutinable upon repeat examination; this particular putative cluster was shown to be a pseudocluster by comparison of the macrorestriction profiles of the respective triple isolates . A strain of A . baumannii serovar 15 had infected 8 patients in a surgical intensive care unit, while a second, genotypically totally different strain of identical serovar had caused infection in one additional patient . With this exception, the correlation between serotyping and analysis of macrorestriction profiles was excellent. Infect Control Hosp Epidemiol, 1996 Jun, 17(6), 366 - 8 An outbreak of multiresistant Acinetobacter baumanii in a university hospital in São Paulo, Brazil; Levin AS et al.; A case-control (46 cases, 23 controls) study was done to determine risk factors for an outbreak of a multiresistant Acinetobacter baumanii (only susceptible to colistin) in a university hospital . The use of antecedent antibacterials and intubation were independent risk factors . No common source was found . With control measures, the outbreak resolved gradually. Clin Infect Dis, 1996 Jun, 22(6), 1026 - 32 Bacteremia due to Acinetobacter baumannii: epidemiology, clinical findings, and prognostic features; Cisneros JM et al.; The number of nosocomial infections caused by Acinetobacter baumannii has increased in recent years . During a 12-month study, there were 1.8 episodes of A . Baumannii bacteremia per 1,000 adults admitted to a hospital in Seville, Spain . Seventy-nine patients were included in the study . A . baumannii bacteremia occurred after a mean (+/- SD) hospitalization of 18 +/- 20 days . In all cases the infections were acquired nosocomially; 71% wee acquired in intensive care units . Ampicillin/ sulbactam was found to be the most active agent against A . baumannii . The common source of the bacteremia was the respiratory tract (32 cases {71%}) . Twenty patients (25%) had septic shock, and 24 (30%) had disseminated intravascular coagulation (DIC) . Treatment with imipenem or ampicillin/sulbactam was most effective (cure rates, 87.5% and 83%, respectively) . The deaths of 27 patients (34%) were related to A baumannii bacteremia . The presence of DIC (odds ratio {OR} = 116.4; P < .0001) and inappropriate antimicrobial treatment (OR = 15.2; P < .01) were independently associated with mortality . We conclude that most A . baumannii isolates are multiresistant and that nosocomial A . baumannii bacteremia may cause severe clinical disease that is associated with a high mortality. J Clin Microbiol, 1996 Jun, 34(6), 1519 - 25 Comparison of outbreak and nonoutbreak Acinetobacter baumannii strains by genotypic and phenotypic methods; Dijkshoorn L et al.; Thirty-one Acinetobacter baumannii strains, comprising 14 strains from 14 outbreaks in different northwestern European cities and 17 sporadic strains, were compared by investigating various properties of the strains including biotype, antibiogram, cell envelope protein electrophoretic profile, ribotype pattern, and the band pattern generated by a novel genomic fingerprinting method, named AFLP, which is based on the selective amplification of restriction fragments . Results showed that 12 strains from unrelated outbreaks were linked together in two clusters according to their similarities by these typing methods, whereas sporadic strains were more heterogeneous . Outbreak strains appeared to be markedly more resistant to antibiotics than nonoutbreak strains . The uniformity of typing characters in two sets of outbreak strains suggests that strains in each cluster have a common clonal origin. Antimicrob Agents Chemother, 1996 Jun, 40(6), 1412 - 8 In vitro activities of quinolones, beta-lactams, tobramycin, and trimethoprim-sulfamethoxazole against nonfermentative gram-negative bacilli; Fass RJ et al.; From 1991 to 1995, 8,975 nonfermentative gram-negative bacilli were isolated from patients at The Ohio State University Medical Center: 71% Pseudomonas aeruginosa, 14% Stenotrophomonas maltophilia, 7.6% Acinetobacter baumannii, and < 2% each of 25 other species . The MICs of trovafloxacin (CP-99,219), ciprofloxacin, ofloxacin, ampicillin-sulbactam, piperacillin, piperacillin-tazobactam, ceftazidime, cefoperazone, ceftriaxone, imipenem, tobramycin, and trimethoprim-sulfamethoxazole (TMP-SMZ) were determined for 308 isolates, representing 13 species, by a standardized broth microdilution method . The activities of all drugs were species dependent . The fluoroquinolones had inconsistent activity against most species, although several relatively uncommon nonfermenters were consistently susceptible or resistant . Trovafloxacin was considerably more active than ciprofloxacin and ofloxacin against S . maltophilia, A . baumannii, and several less common species . Among the beta-lactams, relative activities varied considerably; overall, imipenem had the broadest spectrum of activity but was inactive against S . maltophilia and Burkholderia cepacia isolates . Tobramycin and TMP-SMZ had stereotypic spectra of activity . Tobramycin was active against most species except S . maltophilia, Alcaligenes xylosoxidans subsp . xylosoxidans, Burkholderia spp., and Weeksella virosa . TMP-SMZ was active against most species except P . aeruginosa and Pseudomonas fluorescens-putida . A review of laboratory records indicated few changes in susceptibility patterns from 1991 to 1995; the only clear trend was toward increasing P . aeruginosa resistance to all classes of drugs. Biosci Biotechnol Biochem, 1996 Jun, 60(6), 949 - 56 Cloning of catBCIJFD genes for catechol degradation into chromosomal pobA and genetic stability of the recombinant Acinetobacter calcoaceticus; Jeong EY et al.; A possible obstacle in the development of hybrid strains of Acinetobacter calcoaceticus by the introduction of a metabolic pathway into the chromosome is genetic instability of the resulting recombinant strains . Therefore, the possibility that the pobA gene can be used as a chromosomal cloning site where the transposed genes can be maintained and expressed, was explored in this study . For this purpose, two model hybrid strains of A . calcoaceticus were created, in which a DNA fragment carrying catBCIJFD genes for catabolic degradation of catechol was inserted into pobA in opposite directions of each other, and their genetic stabilities were experimentally examined . Our data demonstrated that the stability of the genes neighboring the insertions depends on the orientations of the insertions . Also, the data further indicated that the functional metabolic pathways introduced into pobA can be expressed successfully as far as the insertion is engineered in an appropriate way . Concurrently, it was proposed that the pobA can be used as a chromosomal cloning site, and that introduction of an useful metabolic pathway into pobA may offer considerable promise to the construction of a hybrid strain with improved metabolic capabilities. Mol Ecol, 1996 Jun, 5(3), 427 - 36 Diversity and distribution of subterranean bacteria in groundwater at Oklo in Gabon, Africa, as determined by 16S rRNA gene sequencing; Pedersen K et al.; This paper describes how ground water was sampled, DNA extracted, amplified and cloned and how information available in the ribosomal 16S rRNA gene was used for mapping diversity and distribution of subterranean bacteria in groundwater at the Bangombe site in the Oklo region . The results showed that this site was inhabited by a diversified population of bacteria . Each borehole was dominated by species that did not dominate in any of the other boreholes; a result that probably reflects documented differences in the geochemical environment . Two of the sequences obtained were identified at genus level to represent Acinetobacter and Zoogloea, but most of the 44 sequences found were only distantly related to species in the DNA database . The deepest borehole, BAX01 (105 m), had the highest number of bacteria and also total organic carbon (TOC) . This borehole harboured only Proteobacteria beta group sequences while sequences related to Proteobacteria beta, gamma and delta groups and Gram-positive bacteria were found in the other four boreholes . Two of the boreholes, BAX02 (34 m) and BAX04 (10 m) had many 16S rRNA gene sequences in common and also had similar counts of bacteria, content of TOC, pH and equal conductivity, suggesting a hydraulic connection between them. Curr Microbiol, 1996 Jun, 32(6), 336 - 42 Oleyl Oleate and Homologous Wax Esters Synthesized Coordinately from Oleic Acid by Acinetobacter and Coryneform Strains Kaneshiro T, Nakamura LK, Nicholson JJ, Bagby MO. Newly isolated Acinetobacter (NRRL B-14920, B-14921, B-14923) and coryneform (NRRL B-14922) strains accumulated oleyl oleate and homolog