J Ind Microbiol Biotechnol, 2001 Jun, 26(6), 333 - 40 Phosphate uptake and release by Acinetobacter johnsonii in continuous culture and coupling of phosphate release to heavy metal accumulation; Boswell CD et al.; A strain of polyphosphate-synthesizing, phosphate-releasing Acinetobacter johnsonii was isolated from a wastewater treatment plant operating enhanced biological phosphate removal (EBPR) and was used to remove La(3+) from solution via precipitation of cell-bound LaPO(4) . The effect of repeated aerobic-anaerobic cycles on the carbon and phosphate metabolism of the organism was studied in attempts to promote increased phosphate flux using a three-stage, continuous bioreactor comprising aerobic, anaerobic and settling vessels . The bioreactor was operated in two modes: In flow-through mode, cells were grown aerobically with acetate as the sole carbon source, promoting excess phosphate uptake (up to 5.0 mmol/l=3.0 mmol/g protein) . Cells were diluted into the anaerobic vessel where phosphate was released (up to 1.0 mmol/l=0.3 mmol/g protein), and thence to waste . The system was initially operated to steady state in flow-through mode, then switched to recycle mode . Here the anaerobic vessel output passed to a settling vessel from which settled cells were returned to the aerobic vessel . Carbon source (acetate) was supplied only to the anaerobic vessel; increased anaerobic acetate uptake was observed during recycle, which was sustained when the system was returned to flow-through mode and was related to increased cellular lipid inclusions by flow cytometry and electron microscopy . These phenomena may represent adaptation of cells to aerobic-anaerobic cycling with aerobic carbon/energy limitation . Addition of La(3+) to the anaerobic vessel during recycle mode promoted removal of 95% of the La(3+) from a 0.1 to 0.3 mM (14-42 ppm) solution at the expense of biogenic phosphate. Appl Environ Microbiol, 2001 Oct, 67(10), 4817 - 27 Cloning and genetic characterization of dca genes required for beta-oxidation of straight-chain dicarboxylic acids in Acinetobacter sp . strain ADP1; Parke D et al.; A previous study of deletions in the protocatechuate (pca) region of the Acinetobacter sp . strain ADP1 chromosome revealed that genes required for utilization of the six-carbon dicarboxylic acid, adipic acid, are linked to the pca structural genes . To investigate the genes involved in adipate catabolism, a 33.8-kb SacI fragment, which corrects a deletion spanning this region, was cloned . In addition to containing known pca, qui, and pob genes (for protocatechuate, quinate, and 4-hydroxybenzoate dissimilation), clone pZR8000 contained 10 kb of DNA which was the subject of this investigation . A mutant strain of Escherichia coli DH5alpha, strain EDP1, was isolated that was able to utilize protocatechuate and 4-hydroxybenzoate as growth substrates when EDP1 cells contained pZR8000 . Sequence analysis of the new region of DNA on pZR8000 revealed open reading frames predicted to be involved in beta-oxidation . Knockouts of three genes implicated in beta-oxidation steps were introduced into the chromosome of Acinetobacter sp . strain ADP1 . Each of the mutants was unable to grow with adipate . Because the mutants were affected in their ability to utilize additional saturated, straight-chain dicarboxylic acids, the newly discovered 10 kb of DNA was termed the dca (dicarboxylic acid) region . Mutant strains included one with a deletion in dcaA (encoding an acyl coenzyme A {acyl-CoA} dehydrogenase homolog), one with a deletion in dcaE (encoding an enoyl-CoA hydratase homolog), and one with a deletion in dcaH (encoding a hydroxyacyl-CoA dehydrogenase homolog) . Data on the dca region should help us probe the functional significance and interrelationships of clustered genetic elements in this section of the Acinetobacter chromosome. Laryngoscope, 2001 Aug, 111(8), 1333 - 7 Comparison of antral tap with endoscopically directed nasal culture; Casiano RR et al.; OBJECTIVES/HYPOTHESIS: The diagnosis of acute bacterial rhinosinusitis continues to generate controversy in critically ill patients . The efficacy of endoscopically directed cultures in these patients is unknown . We compared antral tap (AT) with endoscopic tissue culture (ETC) of the osteomeatal complex in an intensive care unit (ICU) setting . METHODS: Twenty patients admitted to a surgical/trauma ICU were evaluated by AT and ENB for the presence of rhinosinusitis . All patients had 1) a fever of unknown origin without resolution on empiric antibiotic therapy for > or =48 hrs; 2) other sources of fever ruled out; 3) computed tomography scan evidence of mucoperiosteal thickening +/- sinus air/fluid levels; and 4) attempt at conservative treatment with topical decongestants and removal of all nasal intubation . Microbiologic data were collected and analyzed for any statistical difference between groups . RESULTS: A total of 29 sides underwent simultaneous tap and endoscopically directed tissue culture . The mean age was 40 years (range, 23-77 y) with 85% being males . Fifteen of 20 (75%) patients in the AT group were culture-positive . Of the 49 isolates from the AT, 55% yielded Gram-negative bacilli (Acinetobacter sp . 37%) and 45% yielded Gram-positive cocci . The ETC group was culture-positive in 18 of 20 (90%) patients . Of the 52 isolates from the ETC, Gram-negative bacilli were found in 58% (Acinetobacter sp . 33%) and 42% yielded Gram-positive cocci . The ETCs were culture-positive in all but 1 patient with positive taps . There appeared to be a concordance between AT and ETC in 60% of the patients . In five instances (25%), results of the AT or ETC changed ICU management . Two patients ultimately required sinus surgery . CONCLUSIONS: Sinus taps and/or endoscopically directed tissue cultures led to a change in ICU care in 25% of ICU patients studied . In patients with fever of unknown origin and computed tomography evidence of sinusitis, an antral tap continues to provide important information concerning maxillary sinusitis . However, ETC may give as good a representation of the microbiology and secondary inflammatory changes responsible for bacterial ICU rhinosinusitis causing fever of unknown origin . Further study on a larger group of patients is needed. Environ Sci Technol, 2001 Sep 1, 35(17), 3462 - 7 Hydrogen and carbon isotope fractionation during aerobic biodegradation of benzene; Hunkeler D et al.; The main aim of the study was to evaluate hydrogen and carbon isotope fractionation during biodegradation of benzene as a possible tool to trace the process in contaminated environments . Aerobic biodegradation of benzene by two bacterial isolates, Acinetobacter sp . and Burkholderia sp., was accompanied by significant hydrogen and carbon isotope fractionation with hydrogen isotope enrichment factors of -12.8 +/- 0.7 per thousand and -11.2 +/- 1.8 per thousand, respectively, and average carbon isotope enrichment factors of -1.46 +/- 0.06 per thousand and -3.53 +/- 0.26 per thousand, respectively . Inorganic carbon produced by Acinetobacter sp . was depleted in 13C by 3.6-6.2 per thousand as compared to the initial delta13C of benzene, while the produced biomass was enriched in 13C by 3.8 per thousand . The secondary aim was to determine isotope ratios of benzenes from different manufacturers with regard to the use of isotopes for source differentiation . While two of the four analyzed benzenes had similar delta13C values, each of them had a distinct delta2H-delta13C pair and delta2H values spread over a range of 66.5 per thousand . Thus, combined analyses of hydrogen and carbon isotopes may be a more promising approach to trace sources and/or biodegradation of benzene than measuring carbon isotopes only. Curr Infect Dis Rep, 2001 Oct, 3(5), 440 - 444 The Increasing Role of Acinetobacter Species As Nosocomial Pathogens; Bergogne-Berezin E; Among gram-negative organisms playing a significant role in nosocomial infections, Acinetobacter species have attracted increasing attention in intensive care units during the past two decades . Acinetobacter species are implicated in a wide spectrum of infections (eg, bacteremia, nosocomial pneumonia, urinary tract infections, secondary meningitis, superinfections in burn patients) . One of the most striking features of Acinetobacter species is their extraordinary ability to develop multiple resistance mechanisms against major antibiotic classes . They have become resistant to broad-spectrum beta-lactams (third-generation cephalosporins, carboxypenicillins, and increasingly to carbapenems); they produce a wide range of aminoglycoside-inactivating enzymes; and most strains are resistant to fluoroquinolones . In Acinetobacter nosocomial infections, the major problems confronting clinicians in intensive care units are related to the severity of Acinetobacter nosocomial infections and to resistance to major antibiotic classes of these organisms. Kansenshogaku Zasshi, 2001 Aug, 75(8), 662 - 70 {Antimicrobial activities and mechanisms of carbapenem resistance in clinical isolates of carbapenem-resistant Pseudomonas aeruginosa and Acinetobacter spp.}; Sugino Y et al.; We tested the antimicrobial activities of meropenem (MEPM), imipenem (IPM), panipenem (PAPM), piperacillin (PIPC), cefepime (CFPM), aztreonam (AZT), amikacin (AMK), and levofloxacin (LVFX) against 106 clinical Pseudomonas aeruginosa isolates and 64 clinical Acinetobacter spp . isolates with reduced susceptibility to carbapenems . Using NCCLS breakpoints, the percentages of P . aeruginosa strains susceptible to AMK and Acinetobacter spp . strains susceptible to LVFX were found to be 51.1% and 55.6%, respectively, which represented the highest activity among 8 antimicrobial agents in each organism . Referring to the correlations among MICs of carbapenems, MEPM showed a higher activity than IPM and PAPM in both organisms; 29 of the 94 strains (30.9%) of IPM-resistant P . aeruginosa were susceptible to MEPM . Further study for resistance mechanisms to carbapenems by the disk diffusion method using 2-mercaptopropionic acid revealed that 8 of the 64 Acinetobacter spp . isolates (12.5%) were metallo-beta-lactamase producers, while none of 106 P . aeruginosa isolates were metallo-beta-lactamase producers . PCR analysis using blaIMP-specific primers confirmed that 4 of the 8 metallo-beta-lactamase-producing Acinetobacter spp . isolates detected by the disk diffusion method were carrying the blaIMP gene . The identification of metallo-beta-lactamase-producing Acinetobacter spp . isolates implies that metallo-beta-lactamase genes have been disseminated among various gram-negative pathogens. Eur J Intern Med, 2001 Sep, 12(5), 425 - 429 Acinetobacter bacteraemia in a teaching hospital, 1989-1998; Valero C et al.; Background: The mortality rate from bacteraemia is one of the highest among infections in hospitals, especially in the intensive care unit (ICU) . Recently, an increase in nosocomial bacteraemia caused by gram-negative resistant pathogens has been observed . In this work we review the clinical and laboratory findings of adult patients with Acinetobacter bacteraemia in order to identify risk factors associated with mortality . Methods: A retrospective review of the medical records of patients with Acinetobacter bacteraemia identified by blood cultures from the Diagnostic Microbiology Laboratory was conducted between January 1989 and March 1998 . Results: We identified 59 cases of Acinetobacter bacteraemia . Most of the infections (71%) were nosocomial; the majority occurred in the Department of Internal Medicine (28.8%), followed by Haematology (27%) and the ICU (23%) . A . lwoffii was isolated in 52.5% of cases and A . baumannii in 47.5% . The related mortality was 17% . Staying in the ICU was associated with A . baumannii bacteraemia (P<0.004) . An intravascular catheter was the leading source of infection (37%) . Main risk factors were mechanical ventilation (28%), parenteral nutrition (23%) and the presence of a urinary catheter (22%) . In the multivariate analysis the independent prognostic factors for mortality were the presence of shock (P<0.05) and the severity of the underlying disease, according to the classification of McCabe (P<0.05) . Conclusions: The incidence of Acinetobacter bacteraemia has increased in the last decade, mainly since 1995 . The development of septic shock and the severity of the underlying disease appear to be associated with an increase in mortality. J Med Assoc Thai, 2001 Jun, 84(6), 910 - 3 Successful treatment of late onset infection due to multi-drug resistant Acinetobacter Lwoffii in a low birth weight neonate using ciprofloxacin; Chotigeat U et al.; This report presents the case of a low birth weight neonate with multidrug-resistant Acinetobacter Lwoffii infection who was successfully treated with ciprofloxacin and co-trimoxazole . Use of ciprofloxacin in pediatric populations was reviewed . The infant responded to the antibiotic regimen with sterilized cerebrospinal fluid with no adverse effects attributable to the ciprofloxacin . Although ciprofloxacin has been found to cause irreversible damage to cartilage in laboratory animals, a review of the literature found that this complication rarely occurs in pediatric patients . Ciprofloxacin has been found to be effective in the treatment of multidrug-resistant gram negative infections in pediatric patients, including premature infants . Ciprofloxacin should be considered in the treatment of neonatal infection caused by multidrug-resistant gram-negative organisms. Microbios, 2001, 106 Suppl 2, 97 - 104 In vitro effect of ampicillin/sulbactam on Acinetobacter species; Hostacka A; The effects of subinhibitory concentrations (sub-MIC) of ampicillin/sulbactam (AMP/sulbactam), on the surface hydrophobicity and the lipase activity of ten Acinetobacter strains, were examined . The alterations in the activities studied were strain and drug concentration dependent . Most of the strains treated showed a decrease in surface hydrophobicity to a different extent . The hydrophobic character of three strains exposed to 1/4 or 1/8 of the MIC of the antibiotic was changed to a hydrophilic state . The majority of Acinetobacter strains after treatment with antibiotic possessed increased lipolytic activity . AMP/sulbactam even at sub-MIC may interfere with possible virulence factors of Acinetobacter strains in vitro. Natl Med J India, 2001 Jul-Aug, 14(4), 204 - 8 Distribution and in vitro antimicrobial susceptibility of Acinetobacter species on the skin of healthy humans; Patil JR et al.; BACKGROUND: Acinetobacter spp . are ubiquitous in the environment and have emerged as important nosocomial pathogens . The distribution of Acinetobacter spp . In some temperate European countries has been reported . However, similar data from a tropical country such as India are not available . METHODS: Six body sites (antecubital fossa, axilla, forehead with hairline, neck, outer surface of nose and toe webs) from men and women volunteers were sampled with saline-soaked cotton swabs enriched in Baumann's enrichment medium . The isolates were identified to the genus level by chromosomal DNA transformation assay and to the species level by a 16-test biochemical system . The minimum inhibitory concentration for 39 antibiotics was determined by the two-fold agar dilution method . RESULTS: Seven genospecies of Acinetobacter were found at 6 body sites on healthy human skin . Acinetobacter lwoffii was the most dominant comprising 40% of the total number of isolates, followed by A . junii (35%) and A . haemolyticus (16.5%) . The antecubital fossa had the highest colonization frequency (48.5%) . The overall positivity rate of samples was higher from women (26.3%) compared to men volunteers (25%) . Only two Acinetobacter genospecies 1-3 isolates were isolated while no A . radioresistens were isolated . Susceptibility testing revealed no major differences among the 7 Acinetobacter spp . tested . Fluoroquinolones were the most active, while low-to-intermediate resistance was exhibited towards beta-lactams and aminoglycosides . Acinetobacter spp . isolated from the skin showed susceptibility to commonly used antibiotics . CONCLUSION: Seven Acinetobacter genospecies were isolated from 6 different body sites from the skin of healthy human volunteers . Acinetobacter lwoffii was the dominant isolate . The rate of skin carriage was higher in men than in women and the maximally colonized site was the antecubital fossa . All the genospecies displayed susceptibility to most of the commonly used antimicrobials. Icarus, 1990, 85, 241 - 56 Microbial metabolism of tholin; Stoker CR et al.; In this paper, we show that a wide variety of common soil bacteria are able to obtain their carbon and energy needs from tholin (a class of complex organic heteropolymers thought to be widely distributed through the solar system; in this case tholin was produced by passage of electrical discharge through a mixture of methane, ammonia, and water vapor) . We have isolated aerobic, anaerobic, and facultatively anaerobic bacteria which are able to use tholin as a sole carbon source . Organisms which metabolize tholin represent a variety of bacterial genera including Clostridium, Pseudomonas, Bacillus, Acinetobacter, Paracoccus, Alcaligenes, Micrococcus, Corynebacterium, Aerobacter, Arthrobacter, Flavobacterium, and Actinomyces . Aerobic tholin-using bacteria were first isolated from soils containing unusual or sparse carbon sources . Some of these organisms were found to be facultatively anaerobic . Strictly anaerobic tholin-using bacteria were isolated from both carbon-rich and carbon-poor anaerobic lake muds . In addition, both aerobic and anaerobic tholin-using bacteria were isolated from common soil collected outside the laboratory building . Some, but not all, of the strains that were able to obtain carbon from tholin were also able to obtain their nitrogen requirements from tholin . Bacteria isolated from common soils were tested for their ability to obtain carbon from the water-soluble fraction, the ethanol-soluble fraction, and the water/ethanol-insoluble fraction of the tholin . Of the 3.5 x 10(7) bacteria isolated per gram of common soils, 1.7, 0.5, and 0.2%, respectively, were able to obtain their carbon requirements from the water-soluble fraction, the ethanol-soluble fraction and the water/ethanol-insoluble fraction of the tholin . The palatability of tholins to modern microbes may have implications for the early evolution of microbial life on Earth . Tholins may have formed the base of the food chain for an early heterotrophic biosphere before the evolution of autotrophy on the early Earth . Where tholins are present on other planets, they could possibly be metabolized by contaminant microorganisms transported to these bodies via spacecraft . Thus, the presence of tholins should be taken into account when evaluating the planetary quarantine requirements for probes to other planets. BMC Microbiol . 2001;1(1):16 . Epub 2001 Aug 09. Monoclonal antibodies against the iron regulated outer membrane Proteins of Acinetobacter baumannii are bactericidal; Goel VK et al.; BACKGROUND: Iron is an important nutrient required by all forms of life.In the case of human hosts,the free iron availability is 10(-18) M,which is far less than what is needed for the survival of the invading bacterial pathogen.To survive in such conditions, bacteria express new proteins in their outer membrane and also secrete iron chelators called siderophores . RESULTS/ DISCUSSION: Acinetobacter baumannii ATCC 19606, a nosocomial pathogen which grows under iron restricted conditions, expresses four new outer membrane proteins,with molecular weight ranging from 77 kDa to 88 kDa, that are called Iron Regulated Outer Membrane Proteins (IROMPs) . We studied the functional and immunological properties of IROMPs expressed by A.baumanii ATCC 19606.The bands corresponding to IROMPs were eluted from SDS-PAGE and were used to immunize BALB/c mice for the production of monoclonal antibodies . Hybridomas secreting specific antibodies against these IROMPs were selected after screening by ELISA and their reactivity was confirmed by Western Blot . The antibodies then generated belonged to IgM isotype and showed bactericidical and opsonising activities against A.baumanii in vitro.These antibodies also blocked siderophore mediated iron uptake via IROMPs in bacteria . CONCLUSION: This proves that iron uptake via IROMPs,which is mediated through siderophores,may have an important role in the survival of A.baumanii inside the host,and helps establishing the infection. Prikl Biokhim Mikrobiol, 2001 Jul-Aug, 37(4), 398 - 404 {Degradation of mineral oil by Acinetobacter calcoaceticus strain}; Pleshakova EV et al.; The Acinetobacter calcoaceticus strain TM-31 has been isolated from a microbial assemblage of a pilot plant purifying waste water polluted with mineral oil . This strain is capable of efficient degradation of components of mineral oil (alkanes, isoalkanes, and alkyl residues of the naphthene and arene fraction . The strain bears stably inherited plasmids of sizes 120, 9, and 8 kb, which can be transferred into plasmid-free cells of the parental strain and into bacteria of the genus Pseudomonas and ensure the degradation of hexadecane and mineral oil. Clin Infect Dis, 2001 Oct 1, 33(7), 939 - 46 Epub 2001 Aug 22. Risk factors for Acinetobacter baumannii nosocomial bacteremia in critically ill patients: a cohort study; Garcia-Garmendia JL et al.; Nosocomial bacteremia caused by Acinetobacter baumannii (AB) is of increasing concern in critically ill patients, and the risk factors for this infection are not well established . An inception cohort study in a 40-bed medical and surgical intensive care unit (ICU) at a single institution was conducted during a 2-year period to determine the risk factors for AB nosocomial bacteremia . Risk factors related to the underlying diseases, the clinical picture at admission, and those acquired during the stay in the ICU were recorded upon admission and daily throughout the ICU stay . We defined an "invasive procedures index" as the number of invasive procedures performed every day during the ICU stay before the onset of AB bacteremia divided by the number of days in the ICU before the onset of AB bacteremia . Risk factors that were independently associated with AB bacteremia were immunosuppression, unscheduled admission to the hospital, respiratory failure at ICU admission, previous antimicrobial therapy, previous sepsis in the ICU, and the invasive procedures index. Pediatr Surg Int, 2001 Jul, 17(5-6), 390 - 5 Bacterial cholangitis in patients with biliary atresia: impact on short-term outcome; Wu ET et al.; Bacterial cholangitis (BC) is a common complication in patients with biliary atresia (BA) and is characterized by fever, acholic stools and positive blood cultures . The diagnosis is often empirical because the yield of blood cultures is low . It is difficult to differentiate BC from other febrile episodes . In order to characterize the clinical and laboratory features of BC in patients with BA, identify risk factors, and correlate cholangitis with outcome, 37 patients with BA from 1993 to 1998 who underwent a Kasai operation in our hospital were studied . The follow-up period ranged from 6 to 59 months . A total of 107 febrile episodes were documented in these patients . The diagnostic criteria for cholangitis were fever, increased jaundice, or acholic stools . The clinical features, laboratory data, results of bacterial cultures, and outcomes were analyzed retrospectively . A total of 107 febrile episodes, including 78 bouts of cholangitis and 29 non-cholangitis infections, were found in 34 patients . Patients with BC had higher postoperative bilirubin levels (P = 0.02) and less frequent use of prophylactic antibiotics (P = 0.05) than those with non-cholangitis infections . Abnormal white blood cell counts (> 12,000 or <4,000 mm3) tended to be present in patients with BC (P = 0.08) . There were no statistical differences in the risk factors and laboratory data between culture-positive (n = 16) and -negative (n = 62) cholangitis cases . The occurrence of cholangitis significantly reduced survival in both patients with good (P = 0.03) and inadequate bile flow (P = 0.03) . All 9 patients who had never had cholangitis survived during the follow-up period . Repeated attacks of BC further decreased survival probability . The responsive organisms were mainly enteric bacteria, including Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumanni, and Salmonella typhi . The sensitivity tests justified empirical therapy with ceftriaxone . The effectiveness of prophylactic trimethoprim-sulfamethoxazole or neomycin warrants further studies . BC was a highly prevalent postoperative complication in patients with BA, especially those with inadequate bile drainage . It significantly affected early mortality . Aggressive and complete treatment with empirical ceftriaxone was appropriate. J Clin Microbiol, 2001 Sep, 39(9), 3247 - 53 Evaluation of the VITEK 2 system for the identification and susceptibility testing of three species of nonfermenting gram-negative rods frequently isolated from clinical samples; Joyanes P et al.; VITEK 2 is a new automatic system for the identification and susceptibility testing of the most clinically important bacteria . In the present study 198 clinical isolates, including Pseudomonas aeruginosa (n = 146), Acinetobacter baumannii (n = 25), and Stenotrophomonas maltophilia (n = 27) were evaluated . Reference susceptibility testing of cefepime, cefotaxime, ceftazidime, ciprofloxacin, gentamicin, imipenem, meropenem, piperacillin, tobramycin, levofloxacin (only for P . aeruginosa), co-trimoxazole (only for S . maltophilia), and ampicillin-sulbactam and tetracycline (only for A . baumannii) was performed by microdilution (NCCLS guidelines) . The VITEK 2 system correctly identified 91.6, 100, and 76% of P . aeruginosa, S . maltophilia, and A . baumannii isolates, respectively, within 3 h . The respective percentages of essential agreement (to within 1 twofold dilution) for P . aeruginosa and A . baumannii were 89.0 and 88.0% (cefepime), 91.1 and 100% (cefotaxime), 95.2 and 96.0% (ceftazidime), 98.6 and 100% (ciprofloxacin), 88.4 and 100% (gentamicin), 87.0 and 92.0% (imipenem), 85.0 and 88.0% (meropenem), 84.2 and 96.0% (piperacillin), and 97.3 and 80% (tobramycin) . The essential agreement for levofloxacin against P . aeruginosa was 86.3% . The percentages of essential agreement for ampicillin-sulbactam and tetracycline against A . baumannii were 88.0 and 100%, respectively . Very major errors for P . aeruginosa (resistant by the reference method, susceptible with the VITEK 2 system {resistant to susceptible}) were noted for cefepime (0.7%), cefotaxime (0.7%), gentamicin (0.7%), imipenem (1.4%), levofloxacin (2.7%), and piperacillin (2.7%) and, for one strain of A . baumannii, for imipenem . Major errors (susceptible to resistant) were noted only for P . aeruginosa and cefepime (2.0%), ceftazidime (0.7%), and piperacillin (3.4%) . Minor errors ranged from 0.0% for piperacillin to 22.6% for cefotaxime against P . aeruginosa and from 0.0% for piperacillin and ciprofloxacin to 20.0% for cefepime against A . baumannii . The VITEK 2 system provided co-trimoxazole MICs only for S . maltophilia; no very major or major errors were obtained for co-trimoxazole against this species . It is concluded that the VITEK 2 system allows the rapid identification of S . maltophilia and most P . aeruginosa and A . baumannii isolates . The VITEK 2 system can perform reliable susceptibility testing of many of the antimicrobial agents used against P . aeruginosa and A . baumannii . It would be desirable if new versions of the VITEK 2 software were able to determine MICs and the corresponding clinical categories of agents active against S . maltophilia. Gastrointest Endosc, 2001 Sep, 54(3), 346 - 50 Expression of bacterial beta-glucuronidase in human bile: an in vitro study; Leung JW et al.; BACKGROUND: Bacterial beta-glucuronidase causes deconjugation of bilirubin diglucuronide resulting in the precipitation of calcium bilirubinate, which contributes to biliary sludge and stone formation . This process is attributed to enzyme activity produced by the aerobic enterobacteriaceae such as Escherichia coli and Klebsiella sp . The presence of Clostridium sp . was detected in 48 of 56 intrahepatic stones by using polymerase chain reaction techniques and cultured Clostridium perfringens from 14 of 18 unblocked biliary stents . Such bacteria are reported to produce beta-glucuronidase activity . The aim of this study was to determine the proportion of biliary bacteria isolated from pigment stones and stents that produce beta-glucuronidase and to compare the enzyme activity expressed by the different bacteria in human bile . METHODS: A total of 202 bacteria were isolated from blocked and unblocked biliary stents and pigment ductal stones recovered from patients . Of these, 61 bacteria expressed beta-glucuronidase activity in brain heart infusion broth . These 61 bacteria were subsequently grown in human bile under aerobic or anaerobic conditions to the early stationary phase and assayed for beta-glucuronidase activity by using rho-nitrophenyl beta-D glucuronide as substrate . Results were normalized and reported as units of enzyme activity per milligram protein of the bacteria . RESULTS: C . perfringens produced beta-glucuronidase enzyme activity that was 34-fold higher than that for E coli, Staphylococcus, Corynebacterium sp., Bacillus sp., Enterococcus sp., Acinetobacter sp., Streptococcus sp., and Klebsiella sp . CONCLUSION: C . perfringens with its higher enzyme activity is more important in the deconjugation of bilirubin diglucuronide than E coli and Klebsiella sp. J Endotoxin Res, 2001, 7(2), 113 - 8 Structural and serological characterisation of the O-antigenic polysaccharide of the lipopolysaccharide from Acinetobacter strain 96 (DNA group 11); Vinogradov EV et al.; A polysaccharide containing D-Manp, L-Fucp (6-deoxygalactopyranose, fucose) and D-GlcpNAc was isolated by mild acid hydrolysis, followed by gel-permeation chromatography, from the lipopolysaccharide derived from Acinetobacter strain 96 (DNA group 11) . The structure of the O-antigen was determined by compositional analysis and NMR spectroscopy of the polysaccharide as: {carbohydrate structure see text} A monoclonal antibody obtained after immunization of mice with heat-killed bacteria of Acinetobacter strain 96 was shown to bind to the O-antigen and did not cross-react with any Acinetobacter O-antigen of known structure. Infect Control Hosp Epidemiol, 2001 Jun, 22(6), 388 - 91 Infrequent isolation of multiresistant Acinetobacter baumannii from the staff tending a colonized patient with severe burns; Paavilainen T et al.; A patient with severe burns who was colonized by multiresistant Acinetobacter baumannii was cared for in contact isolation by staff intensively trained on hospital hygiene . Of the 1,907 postexposure cultures from the staff and 425 environmental samples, only 0.7% and 4%, respectively, yielded this microorganism . These data show that strict hygienic measures may limit staff colonization and contamination of the environment byA baumannii. J S Afr Vet Assoc, 2001 Jun, 72(2), 97 - 8 Prevalence of microorganisms associated with udder infections in dairy goats on small-scale farms in Kenya; Ndegwa EN et al.; Six hundred and thirty clinically-normal milk samples from dairy goat flocks comprising a mixed population of German Alpine, Toggenburg, Saanen and Galla crosses were examined over a 3-month period to determine the prevalence of bacterial organisms . Bacteria were isolated in 28.7% of the milk samples (181/630) either singly (92.8%) or in combination (7.2%) . The most prevalent bacterial organisms were Staphylococcus spp . (60.3%), followed by Micrococcus spp . (17.7%), Acinetobacter spp . (5%), Actinomyces spp . (5%) and Streptococcus spp . (1.1%) . The Staphylococcus spp . were mainly coagulase negative (64.3%) . Coagulase-negative staphylococci and coagulase-positive staphylococci accounted for 37.5% and 22.7% respectively of the total bacteria isolated . The isolation of bacteria, some of which are important in clinical and subclinical mastitis, in apparently normal caprine milk, indicates that particular attention should be given to the management of these dairy goat flocks in order to avoid the development of cases of clinical mastitis. Biochem Biophys Res Commun, 2001 Aug 24, 286(3), 652 - 8 Molecular characterization of the 56-kDa CYP153 from Acinetobacter sp . EB104; Maier T et al.; CYP153 a cytochrome P450 from Acinetobacter sp . EB104 catalyzes the hydroxylation of unsubstituted n-alkanes . We have decided to use the CYP153 system as a model for mechanistic studies on regioselective n-alkane oxidation and the interaction of hydrophobic substrates with soluble enzymes . Here the molecular cloning of the CYP153 gene is reported . Single specific primer PCR was applied to yield the whole gene sequence via chromosomal walks . CYP153 consists of 497 amino acids (M(r) = 56 kDa) and thus represents an unusually long bacterial P450, containing all P450 typical structural elements . It constitutes the new P450 family CYP153 . The prolonged N-terminus of about 90 amino acids does not contain a so far known membrane-anchoring sequence but a 28-amino acid long amphipathic helix . The relevance of the remarkably long N-terminus and of other sequence motives like the hydrophobic F-G loop is discussed with respect to substrate binding and recognition . Braz J Infect Dis, 2001 Jun, 5(3), 103 - 10 Multiple organ failure in septic patients; Bilevicius E et al.; Multiple organ failure (MOF) is the main cause of death in ICUs, especially affecting septic patients . It is strongly related to number of systems with failure, type of system involved, risk factors such as age, previous chronic diseases, delayed or inadequate resuscitation, persistent infection, immune suppression, and others . The prognoses is worse for patients rather than in elective or emergency surgical patients . The objective of this article is to provide data from our university teaching hospital ICU related to the incidence of septic patients, the distribution of MOF, and distribution of failure among each of the organs . The mortality rate, relationship between mortality and age, and mortality and types of organs affected were evaluated . The main bacterial causes of sepsis were also identified . A retrospective evaluation was done of 249 patients admitted to the ICU in a 4 month period during 1999 . Fifty four patients had sepsis diagnosed by ACCS/SCCM criteria . There were 37 men and 17 women; 24 medical and 30 post-surgical patients (9 after elective surgery and 21 emergency patients) . APACHE II score was calculated on admission and MOF, measured for the first five days, was diagnosed using Marshall and Meakins criteria . The statistical method used was non-parametric Mann-Whitney test, p<0.05 was considered significant . The incidence of sepsis was recorded in 54/249 patients (22%) . Thirty of these 54 patients (56%) died . Death occurred in 2 of 11 patients with one organ failure (18%), in 14/27 with 2 or 3 organ failures (52%), and 14/16 with 4 or more organ failures (88%) . None of the three patients 15 to 20 years old died, 17/32 (55%) patients age 21-60 years, and >61 years 13/19 (68%), died . There were 23 patients with positive bacterial culture . The most frequent bacteria found were: Pseudomonas aeruginosa (5), multiresistant Acinetobacter baumanii (3), Staphylococcus epidermidis (3), Enterobacter aerogenes (3), Klebsiella pneumoniae (2) and multiresistant Staphylococcus aureus (2) . The mean value +/- SD of APACHE II (mortality risk) for survivors was 21 +/- 18 and for non-survivors 42 +/- 26 (p<0.001) . We conclude that MOF due to sepsis in an ICU is frequent, with high mortality related to the number of failing organs, age and high APACHE II. Biotechnol Bioeng, 2001 Sep, 76(2), 108 - 14 Metabolic engineering of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) composition in recombinant Salmonella enterica serovar typhimurium; Aldor I et al.; A recombinant strain of Salmonella enterica serovar Typhimurium (mutant in propionate-activation activity) was metabolically engineered to control the composition of poly(3-hydroxybutyrate-co-3-hydroxy- valerate) (PHBV), a polyhydroxyalkanoate copolymer with commercially desirable properties . A gene (prpE) encoding propionyl-CoA synthetase was placed under the control of the IPTG-inducible taclacUV5 promoter (P(taclacUV5)) while the polyhydroxyalkanoate synthesis operon (phaBCA) from Acinetobacter sp . RA3849 was coexpressed under the control of the arabinose-inducible araBAD promoter (P(BAD)) . S . enterica, harboring both constructs, was grown in medium containing a fixed substrate concentration and the composition of the copolymer was varied between 2 mol% and 25 mol% 3-hydroxyvalerate by controlling the IPTG level in the medium . This "dial-a-composition" system should find application in cases where the substrate concentration of a feedstream for PHBV bioplastic production is not adjustable . Diagn Microbiol Infect Dis, 2001 Jul, 40(3), 117 - 20 Interactions of colistin and rifampin on multidrug-resistant Acinetobacter baumannii; Giamarellos-Bourboulis EJ et al.; The increased incidence of nosocomial infections by multidrug-resistant Acinetobacter spp creates demand on the application of some combinations of older antimicrobials on that species . The in vitro activities of colistin and of rifampin and of their interaction were tested on 39 nosocomial isolates of Acinetobacter baumannii . All isolates were resistant to ampicillin/sulbactam, to 3(rd) and 4(th) generation cephalosporins, to amikacin and to ciprofloxacin . MICs were determined by a microdilution technique and interactive studies between 1x or 4x MIC of colistin and rifampin were performed by the time-kill assay . Rifampin was applied at a concentration of 2 microg/mL which is equal to its mean serum level . All isolates were inhibited by colistin and only 15.2% by rifampin . Synergy between 1x MIC of colistin and rifampin was detected in 15.4% of isolates at 6 h of growth and in 51.3% of isolates at 24 h of growth . Synergy between 4x MIC of colistin and rifampin was detected in 15.4% of isolates at 6 h of growth and in 66.7% of isolates at 24 h of growth . It is concluded that colistin is highly active on multidrug-resistant Acinetobacter spp and its activity on A.baumannii is increased in the presence of rifampin, so that their administration might be proposed for nosocomial infections by these isolates. Ethiop Med J, 2001 Apr, 39(2), 97 - 104 Prevalence and antibiotic susceptibility pattern of bacterial isolates from blood culture in Tikur Anbassa Hospital, Addis Ababa, Ethiopia; Asrat D et al.; Between Mid-1996 and Mid-1998, 238 bacteria strains isolated from blood culture of adult patients of Tikur Anbassa Hospital, Addis Ababa, Ethiopia, were retrospectively analyzed for their frequency of isolation and antibiotic susceptibility pattern . Coagulase negative Staphylococcus aureus (CNS) were isolated with the highest frequency 103 (43.3%), followed by Staphylococcus aureus 34(14.3%), Klebsiella spp . 23(9.7%), E . Coli 19(8.1%), Pseudomonas spp . 16(6.7%), Acinetobacter spp . 12(5%), Salmonella spp . 9(3.8%) and miscellaneous group 22(9.2%) . The gram positive bacteria constituted 149(62.6%) of the total blood isolates . It is suggested that a proportion of both the gram positive and gram negative isolated represent contaminants at blood sampling . Rates of susceptibility for gram positive range from 12% to 76%, and for gram negatives range from 8% to 46% . In general, rates of susceptibilities to all antibiotics tested for gram negatives were very low as compared to gram positives . Among the gram positives, more than half of the isolates were sensitive to amoxicillin + clavulanic acid, ampicillin, carbenicillin, cephalothin, chloramphenicol, erythromycin and methicillin . Gram negative bacteria showed a high rate of resistance to many of the commonly prescribed antimicrobial drugs: amoxicillin + clavulanic acid (65%), ampicillin (87.5%), amoxicillin (91.7%), carbenicillin (75%), cephalothin (73.6%), chloramphenicol (65%), gentamicin (55.6%), kanamycin (54%), trimethoprim-sulphamethoxazole (64%) and tetracycline (61%) . If generally considered, only gentamicin and kanamycin were relatively effective against gram negatives . Over 85% Salmonella spp were sensitive to chloramphenicol and trimethoprim-sulphamethoxazole . Compared to previous studies done in the same hospital, there is a higher rate of antibiotic resistance for most types of blood culture isolates particularly for gram negatives . The rational use of drugs should be practiced in order to minimize the spread of drug resistant bacteria. Ethiop Med J, 2001 Apr, 39(2), 113 - 21 Otitis media seen in Yekatit 12 Hospital; Tessema G; Two thousand three hundred and thirty four selected patients with ear problem were seen in one of the ENT out patients department of Yekatit 12 Hospital from September 1994 to August 1996 were prospectively studied . Most of the patients came from Addis Ababa . Major clinical presentations were ear pain, purulent ear discharge, uni or bilateral decreased hearing ability . Patients were carefully evaluated by physical examination, otoscopy examination of the ear, schuilers view of the mastoid bone, audiometry findings and pus culture results . Diagnosis of these patients revealed that 1,630 (69.8%) had otitis while the rest 704 (30.16%) had other ear problems like ear wax, tinnitus and otitis external . One hundred two hundred thirty two patients (52.8%) had chronic otitis media with purulent discharge and decreased hearing ability, while 245 patients (10.5%) had chronic otitis media with out purulent discharge but with decreased hearing ability . Ninety six patients (4.1%) had acute otitis media and 57 patients (2.4%) had chronic seromucinous otitis media with decreased hearing ability . The micro-organisms identified include klebsiella spp . (28.97%), E . coli (10.7%), Citrobacter (3.6%), Acinetobacter (4.7%), S . aureus (3.57%), P . Valgaris (4.3%), S . Epidermidis (4.54%) and Dephtheroids (7.3%) . Eighty nine patients with acute otitis media were completely cured and regained their hearing ability, the rest did not regain their hearing ability despite treatment . A combination of antibiotics and surgical treatment is recognized as the most effective intervention in this situation . The management of the chronic draining ear are: 1) . To achieve a clean healed dry ear, 2) to obtain an air-containing middle ear space, 3) to rehabilitate hearing . The prevention of deafness and treatment of chronic draining ear disease especially in children is surgery which is not yet fully practiced in our centers. Appl Microbiol Biotechnol, 2001 Jul, 56(1-2), 243 - 8 Antimicrobial activity of argon fluoride (ArF) excimer laser on gram-negative bacteria; Charvalos E et al.; The objective of this study was to evaluate the antibacterial activity of argon fluoride (ArF) excimer laser radiation on clinically important strains of gram-negative bacteria . The antibacterial activity of ArF excimer laser radiation was evaluated on two Acinetobacter baumannii, one Enterobacter cloacae, three Escherichia coli, two Helicobacter pylori, one Klebsiella pneumoniae and two Pseudomonas aeruginosa strains . The strains were isolated from clinical specimens and typed by the usual biochemical procedures . Square agar plates of 12 x 12 cm were divided into rectangular (2 x 3 cm) regions and spread with 0.5x 10(4) colony forming units (CFU)/ml of bacterial suspension . The excess liquid was removed and the plates were allowed to dry for 30 min . A total of 96 rectangular (2x3 cm) regions were used for each strain, in order to test an equal number of laser parameters . Each rectangular region was irradiated with different laser parameters, using a 193 nm ArF excimer laser, linked with a simple Galilean afocal system and a rectangular diaphragm of the same dimensions as the original laser beam cross-section, at a distance of 10 cm from the irradiated surface . This system was used in order to keep the laser pulse energy under 80 mJ and to cut-out the non-transverse electromagnetic mode branches of the laser beam . We then studied the bacterial survival ratio versus the number of laser pulses, the repetition frequency and the total laser beam fluence . Our results showed that the total laser beam fluence was the most important parameter to consider in evaluating the bactericidal effect of ArF excimer laser radiation . A critical value of the total fluence was determined for each strain, such that, for laser beam fluences greater than this critical value, no colonies appeared to survive while, for laser fluences less than this critical value, the survival ratio did not exceed 2 x 10(7) CFU (2 x 10(-5)%) . These critical values were found to vary between 8 J/cm2 and 16 J/cm2 for the bacterial species studied . Under these conditions, ArF laser irradiation is promising for the sterilisation of hard surfaces and for in situ application. Rev Esp Quimioter, 2000 Dec, 13(4), 405 - 7 {Activity of imipenem and meropenem against strains of Acinetobacter baumannii isolated from various Chilean hospitals}; Bello H et al.; The activity of two carbapenem compounds, imipenem and meropenem, against 447 strains of Acinetobacter baumannii isolated between 1990 and 1998 in different Chilean hospitals was determined . MIC ranges, MIC(50) and MIC(90), were determined by an agar dilution method . Similar antibacterial activities were observed for both antibacterials; however, a slight increase in the MIC(50) of imipenem and meropenem, and in the MIC(90) of meropenem was found among strains isolated from 1997-1998 . Although A . baumannii remains susceptible to these antibiotics, the MIC(50) and MIC(90) have increased in recent years. Rev Esp Quimioter, 2000 Dec, 13(4), 401 - 4 {Antibacterial activity of aminoglycosides against nosocomial strains of Acinetobacter baumannii isolated between 1990 and 1999}; Gonzalez G et al.; The antibacterial activity of selected aminoglycosides against 487 nosocomial strains of Acinetobacter baumannii isolated from Chilean hospitals between 1990 and 1998 was investigated . Plasmid profiles were determined for some resistant isolates . A high frequency of resistant strains was found for all aminoglycosides assayed, with values ranging from 47% for amikacin (1990-1992) to 88% for gentamicin (1993-1994) . The cure of a plasmid greater than 30 kb was associated with the loss of amikacin, kanamycin and neomycin resistance in some isolates . This result suggests that plasmid may harbor the genes encoding for the combination of aminoglycoside-modifying enzymes AAC(6')I+APH(3') . Gentamicin resistance was not lost among cured strains, suggesting it may be encoded by genes located on the bacterial chromosome or transposons inserted on the chromosome. Rev Esp Quimioter, 2000 Dec, 13(4), 394 - 400 {Evolution of antimicrobial susceptibility of Acinetobacter baumannii clinical isolates}; Lopez-Hernandez S et al.; Acinetobacter baumannii is a microorganism frequently implicated in colonization and infection in hospitalized patients . An increase of resistance has been observed in recent years making these infections difficult to treat . The in vitro activity of 24 antibiotics, 15 betalactam agents and nine nonbetalactams, was studied in 156 A . baumannii clinical isolates . The strains were collected from different clinical samples obtained from inpatients (92%) and 8% were from outpatients . Evolution of susceptibility from January 1995 to December 1997 was studied . MIC of the following antibiotics was determined by the agar dilution method: ampicillin, ticarcillin, piperacillin, ampicillin-sulbactam, amoxicillin- clavulanic acid, ticarcillin-clavulanic acid, piperacillin-tazobactam, cefotaxime, ceftazidime, cefepime, imipenem, meropenem, clavulanic acid, sulbactam, tazobactam, amikacin, gentamicin, tobramycin, ofloxacin, doxycycline, fosfomycin, rifampin, azithromycin and colistin . Low antimicrobial susceptibility was observed in most A . baumannii strains . Colistin, imipenem, meropenem and ampicillin-sulbactam showed the greatest susceptibility (100, 88.4, 88.4 and 84.6%, respectively) . A . baumannii strains from inpatients showed a lower antimicrobial susceptibility than strains from outpatients, who showed a high percentage of susceptibility to most antibiotics . Rifampin and azithromycin showed certain in vitro activity against the most susceptible A . baumannii strains . A progressive decrease in susceptibility to most antibiotics was observed during the period studied . Carbapenem-resistant A . baumannii emerged in 1996 and increased in 1997. J Microsc, 2001 Aug, 203(Pt 2), 227 - 30 Rapid contrasting of ultrathin sections using microwave irradiation with heat dissipation; Hernandez-Chavarria F et al.; The use of microwave irradiation (MWI) to accelerate fixation, dehydration and contrasting (staining) for electron microscopy has been applied to the development of rapid methods to process biological samples in electron microscopy . A simple explanation is that the reduced time in those procedures is due to heating . In this paper we propose a contrasting method for thin sections that avoids the thermal effects of MWI . Grids with thin sections of mouse kidney, the dinoflagellate Alexandrium monilatum, spermatophores of the fly Archicepsis diversiformis, the bacteria Acinetobacter calcoaceticum and Enterobacter cloacae were placed into Beem capsules and stained with uranyl acetate and lead citrate, while immersed in an ice-water bath, and irradiated for periods ranging from 30 s to 2 min . After each contrasting procedure, the Beem capsule was filled with distilled water to wash the grids under MWI with the same irradiation time as used to contrast . Good results were obtained on irradiating for 1 min and the temperature of the Beem capsule was maintained around 5 degrees C. J Pak Med Assoc, 2001 Jun, 51(6), 213 - 5 Blood stream infections in a medical intensive care unit: spectrum and antibiotic susceptibility pattern; Mahmood A; OBJECTIVE: To determine the type and sensitivity pattern of causative organisms of septicaemia in intensive care unit, to prepare a guideline for empirical antibiotic therapy . SETTING: Department of pathology and adult medical intensive care unit, PNS SHIFA (Naval Hospital), Karachi . METHODS: The study was conducted from January 1997 to June 1999 . Blood specimens for culture were drawn from patients who developed symptoms/signs of bacteraemia/septicaemia 48 hours or more after admission in medical ICU . The specimens were inoculated into Brain Heart Infusion broth . Subcultures were done on days 1,2,3,5,7 and 10 . The isolates were identified by standard biochemical tests . Antibiotic susceptibility pattern of the isolates was studied by Modified Kirby Baur method . RESULTS: Eighty-six aerobic organisms were isolated . They included Staphylococcus aureus(n = 34), Pseudomonas aeruginosa (n = 13), Escherichia coli and Enterobacter spp(n = 9 each), Klebsiella pneumoniae(n = 8), Acinetobacter spp and Serratia spp(n = 5 each), Citrobacter diversus(n = 2) and Proteus vulgaris(n = 1) . On antibiotic susceptibility testing, 48.18% Staphylococcus aureus isolates were methicillin resistant . Susceptibility to other common drugs was also quite low while 100% of these were susceptible to vancomycin and amikacin . In case of gram negative rods more than 80% were resistant to ampicillin and cotrimoxazole . Susceptibility to gentamicin was as low as 25% for Klebsiella pneumoniae to 44.4% in case of Escherichia coli . Susceptibility to the third generation cephalosporins and the quinolone tested (ciprofloxacin) varied between 50-75% . All these isolates except Pseudomonas aeruginosa were susceptible to imipenem and amikacin . CONCLUSION: In view of the isolation of antibiotic resistant organisms, vancomycin in combination with amikacin or imipenem are the drugs of choice for empirically treating blood stream infections in ICU . Infection control procedures and antibiotic control policies can help to tackle this problem. Perit Dial Int, 2001 May-Jun, 21(3), 296 - 301 Polymicrobial outbreak of intermittent peritoneal dialysis peritonitis during external wall renovation at a dialysis center; Cheng VC et al.; OBJECTIVE: To investigate an outbreak of peritonitis in intermittent peritoneal dialysis (IPD) patients . DESIGN: An outbreak investigation was performed to identify the etiology of the polymicrobial outbreak, and a retrospective case-control study was conducted to assess the risk factors for development of peritonitis . SETTING: Renal dialysis center . PATIENTS: Ten episodes of peritonitis occurred in 8 of 61 patients over a 6-month period in which 669 IPD procedures were analyzed . INTERVENTIONS: Field visit to renal dialysis center to examine the entire IPD procedure, inspect the hospital environment, and perform air bacterial count . MAIN OUTCOME MEASURES: The environmental factors and risk factors contributing to the polymicrobial peritonitis outbreak in IPD patients . The incidence of IPD peritonitis was determined before and after interventions . RESULTS: The causative organisms included Acinetobacter baumanii (6), Stenotrophomonas maltophilia (2), Pseudomonas aeruginosa (1), Candida albicans (1), C . tropicalis (1), Enterococcus (3), and Enterobacteriaceae (2) . Four episodes of peritonitis involved infection by more than one organism . Air sampling of the environment detected a median of 110 colony forming units of bacteria per cubic meter of air, 10% of which were found to be Acinetobacter baumanii . The source of this polymicrobial outbreak was attributed to the bamboo scaffolding structure covering the external wall of the hospital during renovation . A retrospective case-control study indicated that the absence of the flush-before-fill step was a risk factor for development of peritonitis . CONCLUSION: In addition to invasive aspergillosis in transplant or oncology patients, Acinetobacter peritonitis in dialysis patients should be considered another microbial cause of outbreak associated with hospital renovation. J Appl Microbiol, 2001 Aug, 91(2), 290 - 8 Studies on bioemulsifier production by Acinetobacter strains isolated from healthy human skin; Patil JR et al.; AIMS: In recent years, interest has been growing in the search for novel bioemulsifiers . Many bacterial genera including Acinetobacter have been reported to produce bioemulsifiers . The present study aims to screen Acinetobacter isolates from healthy human skin for bioemulsifier production . Methods and Results: Acinetobacter junii SC14 produced maximum bioemulsifier in the presence of almond oil during stationary growth phase at 37 degrees C and pH 7.2 . Partially purified, nondialysable bioemulsifier from SC14 was a proteoglycan . The protein and polysaccharide fractions resulted in 95.2% reconstitution of the emulsification activity . The role of esterase in the release of cell-bound emulsifier and the contribution of capsular polysaccharide to the emulsification activity were observed . CONCLUSION: Acinetobacter strains from human skin exhibited better emulsification activity than that by burn wound or soil isolates, owing to the inherent differences in chemical microenvironment of their habitats . SIGNIFICANCE AND IMPACT OF THE STUDY: Investigation of skin commensals, especially acinetobacters, would lead to the discovery of novel bioemulsifiers with interesting properties . Attempts of screening and strain improvement directed towards skin commensals will open up new avenues for strains producing bioemulsifier on a commercial scale. J Appl Microbiol, 2001 Aug, 91(2), 237 - 47 Modelling bacterial spoilage in cold-filled ready to drink beverages by Acinetobacter calcoaceticus and Gluconobacter oxydans; Battey AS et al.; AIMS: Mathematical models were created which predict the growth of spoilage bacteria in response to various preservation systems . METHODS AND RESULTS: A Box-Behnken design included five variables: pH (2.8, 3.3, 3.8), titratable acidity (0.20%, 0.40%, 0.60%), sugar (8.0, 12.0, 16.0 * Brix), sodium benzoate concentration (100, 225, 350 ppm), and potassium sorbate concentration (100, 225, 350 ppm) . Duplicate samples were inoculated with a bacterial cocktail (100 microl 50 ml(-1)) consisting of equal proportions of Acinetobacter calcoaceticus and Gluconobacter oxydans (5 x 10(5) cfu ml(-1) each) . Bacteria from the inoculated samples were enumerated on malt extract agar at zero, one, two, four, six, and eight weeks . CONCLUSION: The pH, titratable acidity, sugar content, sodium benzoate, and potassium sorbate levels were all significant factors in predicting the growth of spoilage bacteria . SIGNIFICANCE AND IMPACT OF THE STUDY: This beverage spoilage model can be used to predict microbial stability in new beverage product development and potentially reduce the cost and time involved in microbial challenge testing. Arthritis Rheum, 2001 Jul, 44(7), 1689 - 97 Chromosomal DNA from a variety of bacterial species is present in synovial tissue from patients with various forms of arthritis; Gerard HC et al.; OBJECTIVE: We and others have reported the presence of Chlamydia and other bacterial species in joint specimens from patients with reactive arthritis (ReA) . The present study was conducted to investigate whether bacteria other than those specified by diagnostic criteria for ReA could be identified in synovial fluid (SF) or tissue from patients with various arthritides, and whether the presence of such organisms corresponds to particular clinical characteristics in any patient set or subset . METHODS: DNA in synovial biopsy samples and SF obtained from 237 patients with various arthritides, including ReA, rheumatoid arthritis, and undifferentiated oligoarthritis, was assayed by polymerase chain reaction (PCR) using "panbacterial" primers; we chose only samples known to be PCR negative for Chlamydia, Borrelia, and Mycoplasma species . PCR products were cloned, and cloned amplicons from each sample were sequenced; DNA sequences were compared against all others in GenBank for identification of bacterial species involved . RESULTS: Ten percent of patient samples were PCR positive in panbacterial screening assays . Bacterial species identified belonged to the genera Neisseria, Acinetobacter, Moraxella, Salmonella, Pseudomonas, and others . Thirty-five percent of PCR-positive patients showed the presence of DNA from more than a single bacterial species in synovium; overall, however, we could identify no clear relationship between specific single or multiple bacterial species in the synovium and any general clinical characteristics of any individual or group of patients . CONCLUSION: This analysis provides the first systematic attempt to relate bacterial nucleic acids in the synovium to clinical characteristics, joint findings, and outcomes . Many patients with arthritis have bacterial DNA in the joint, and, in some cases, DNA from more than a single species is present . However, except for 1 case of a control patient with staphylococcal septic arthritis, it is not clear from the present study whether the synovial presence of such organisms is related to disease pathogenesis or evolution in any or all cases. Biochem J, 2001 Aug 1, 357(Pt 3), 893 - 8 Ca(2+) stabilizes the semiquinone radical of pyrroloquinoline quinone; Sato A et al.; Spectroelectrochemical studies were performed on the interaction between Ca(2+) and pyrroloquinoline quinone (PQQ) in soluble glucose dehydrogenase (sGDH) and in the free state by applying a mediated continuous-flow column electrolytic spectroelectrochemical technique . The enzyme forms used were holo-sGDH (the holo-form of sGDH from Acinetobacter calcoaceticus) and an incompletely reconstituted form of this, holo-X, in which the PQQ-activating Ca(2+) is lacking . The spectroelectrochemical and ESR data clearly demonstrated the generation of the semiquinone radical of PQQ in holo-sGDH and in the free state in the presence of Ca(2+) . In contrast, in the absence of Ca(2+) no semiquinone was observed, either for PQQ in the free state (at pH 7.0) or in the enzyme (holo-X) . Incorporation of Ca(2+) into the active site of holo-X, yielding holo-sGDH, caused not only stabilization of the semiquinone form of PQQ but also a negative shift (of 26.5 mV) of the two-electron redox potential, indicating that the effect of Ca(2+) is stronger on the oxidized than on the reduced PQQ . Combining these data with the observations on the kinetic and chemical mechanisms, it was concluded that the strong stimulating effect of Ca(2+) on the activity of sGDH can be attributed to facilitation of certain kinetic steps, and not to improvement of the thermodynamics of substrate oxidation . The consequences of this conclusion are discussed for the oxidative as well as for the reductive part of the reaction of sGDH. J Microbiol Immunol Infect, 2001 Jun, 34(2), 131 - 7 Efficacy of cefepime versus ceftazidime in the treatment of adult pneumonia; Lin JC et al.; Effective empiric treatment of pneumonia requires antibiotic coverage against gram-negative and gram-positive pathogens, including drug-resistant isolates . This study evaluated the efficacy of cefepime treatment in 20 patients with community-acquired pneumonia (CAP) and 21 patients with hospital-acquired pneumonia (HAP), and ceftazidime treatment in 20 patients with HAP . The mean age of patients was over 70 years . More than half of the patients had multiple lobe involvement . There was no significant difference in the severity of illness according to the acute physiology, age, chronic health evaluation (APACHE) III score between the HAP-cefepime and HAP-ceftazidime group . The most common bacteria isolated from sputum of patients with CAP were Streptococcus pneumoniae (n = 7), Klebsiella pneumoniae (n = 4), and Pseudomonas aeruginosa (n = 2) . In patients with HAP, P . aeruginosa (n = 13), Acinetobacter baumannii (n = 11), Serratia marcescens (n = 6), K . pneumoniae (n = 5), Stenotrophomonas maltophilia (n = 5), Enterobacter cloacae (n = 3), Citrobacter spp . (n = 2), and Escherichia coli (n = 2) were isolated . The cure rates were 95%, 76%, and 60% in the CAP-cefepime group, the HAP-cefepime group, and the HAP-ceftazidime group, respectively . The increased rates of antimicrobial resistance commonly found among isolates causing CAP and HAP indicate that extended-spectrum antimicrobial agents, such as cefepime, would be more appropriate therapeutic agents. Ann Acad Med Singapore, 2001 May, 30(3), 234 - 8 The role of early tracheostomy in critically ill neurosurgical patients; Teoh WH et al.; OBJECTIVE: To determine the value of early tracheostomy (within 7 days) in ventilated neurosurgical patients . METHODS: Retrospective review of intubated patients in the neurosurgical intensive care unit (NICU) who underwent elective open tracheostomies for prolonged ventilation . RESULTS: Thirty patients over a 2-year period were analysed . There were 19 males and 11 females, mean age 53.9 +/- 18.1 years (range 14 to 89), and mean Glasgow Coma Scale (GCS) score on admission 7.1 +/- 3.8 (range 3 to 15) . The underlying disease aetiology was cerebrovascular disease in 53% of patients, head trauma in 33% and tumour or infection in 13% . Tracheostomy was performed after a mean period of 8.5 +/- 3.5 days (range 2 to 18), with patients requiring ventilation for a mean duration of 13.5 +/- 6.3 days (range 3 to 31) . Complications were minimal; 1 wound infection (3.3%) and 4 tube obstructions (13.3%) . Patients who underwent elective early tracheostomy (Group 1 = within 7 days) had poorer GCS on admission (6.3 +/- 2.9 versus 7.7 +/- 4.3 in Group 2, P = 0.271) . Tracheostomy was performed after a mean of 5.3 +/- 1.7 days in Group I vs . 10.6 +/- 2.7 days in Group 2 . Group 1 patients had faster recovery from nosocomial pneumonia (12.3 +/- 6.2 versus 17.9 +/- 12.5 days, P = 0.168), shorter duration of ventilation (9.8 +/- 5.9 versus 16.0 +/- 5.4 days, P = 0.007), and reduced incidence of multibacterial tracheobronchial colonisation (42% versus 72%, P = 0.098) . The most prevalent organisms were Acinetobacter baumanii (43.3%), Pseudomonas (40%), methicillin-resistant Staphylococcus aureus (MRSA) (33%), Klebsiella (30%) and Staphylococcus aureus (26.7%) . CONCLUSION: Early tracheostomy in selected neurosurgical patients with poor GCS scores was associated with reduced incidence of tracheobronchial colonisation by multiple pathogens, improvement in chest infections, and rapid weaning from ventilatory support. J Infect Chemother, 2001 Jun, 7(2), 117 - 20 Surveillance of bacterial resistance among isolates in Shanghai in 1999; Wang F et al.; We report here surveillance data on the bacterial resistance of clinical isolates from 11 Shanghai hospitals in 1999, for guidance in the clinical use of antibacterial agents . Of the 14,855 strains collected, 5130 (34.5%) were Gram-positive cocci and 9725 (65.5%) were Gram-negative bacilli . The most common organisms in descending order of frequency, were: Escherichia coli (16%), coagulase-negative staphylococci (CNS; 14.3%), Klebsiella spp . (12.3%), Staphylococcus aureus (11.5%), Pseudomonas aeruginosa (9.2%), Acinetobacter spp . (8.1%), and Enterococcus spp . (6.6%) . Methicillin-resistant strains accounted for 64% and 77% of S . aureus and CNS, respectively . The methicillin-sensitive strains were susceptible to most agents tested, while most methicillin-resistant strains were resistant to these agents . No vancomycin-resistant staphylococci were identified . Vancomycin-resistant strains accounted for 3.6% of Enterococcus fecalis and 1.7% of E . fecium . E . coli strains resistant to piperacillin, gentamicin, and fluoroquinolones accounted for 50% or more of the strains, and the resistance rates of Klebsiella spp., Enterobacter spp., Citrobacter spp., and Acinetobacter spp . to third-generation cephalosporins had increased markedly compared with rates in recent years . Resistance rates of P . aeruginosa to ceftazidime and imipenem (27% and 20%, respectively) had also increased compared with rates in recent years . A national strategy on the limited and prudent use of antibiotics is urgently needed. Carbohydr Res, 2001 Jul 19, 333(4), 339 - 42 A very efficient method to cleave Lipid A and saccharide components in bacterial lipopolysaccharides; Manzo E et al.; A novel mild procedure for the selective cleavage of ketosidic linkages is developed using ceric ammonium nitrate (CAN) in anhydrous N,N-dimethylformamide . Its application to lipopolysaccharides (LPS) is very significant because in the so far investigated LPS, the connection between the Lipid A region and the oligo(poly)saccharide part is always a keto-sugar . This procedure has been tested on LPS of Escherichia coli which contains Kdo as a linker between Lipid A and OPS and on Acinetobacter haemoliticus which contains D-glycero-D-talo-2-octulopyranosonic acid (Ko) as a linker and it performed efficiently in both cases. J Chemother, 2001 Jun, 13(3), 260 - 4 Antibiotic resistance among Gram-negative non-fermentative bacteria at a teaching hospital in Saudi Arabia; Eltahawy AT et al.; The incidence and antimicrobial resistance of Gram-negative non-fermentative bacteria isolated over 1 year at King Abdulaziz University Hospital, Jeddah, Saudi Arabia were investigated . A total of 499 of these microorganisms were collected and account for 16% of all Gram-negative bacteria isolated . The most common species were Pseudomonas aeruginosa 291 (56%), Acinetobacter baumannii 170 (34%), and Stenotrophomonas maltophilia 35 (7%) . 168 (34%) of these microorganisms were isolated from Intensive Care Unit (ICU), 147 (30%) from General Medicine, and 24 (25%) from Surgery wards . ICU was the main site of isolation of P . aeruginosa and S . maltophilia, while A . baumannii was more frequently isolated from medicine and surgery units . The vast majority of the isolates were resistant to many antibiotics tested . The antimicrobial resistance patterns of P . aeruginosa showed lowest resistance to imipenem (13%), amikacin (17%), and ciprofloxacin (18%) . Imipenem was also the most active antimicrobial agent against A . baumannii (15%) resistance . S . maltophilia exhibited multi-drug resistance, and was susceptible only to sulfonamide (6%). J Korean Med Sci, 2001 Jun, 16(3), 262 - 70 Antimicrobial resistance surveillance of bacteria in 1999 in Korea with a special reference to resistance of enterococci to vancomycin and gram-negative bacilli to third generation cephalosporin, imipenem, and fluoroquinolone; Lee K et al.; The trend of antimicrobial resistance of bacteria isolated from patients in 30 Korean hospitals in 1999 was analyzed with a particular attention to cefotaxime- or fluoroquinolone-resistant gram-negative bacilli, imipenem-resistant Pseudomonas aeruginosa, and vancomycin-resistant enterococci . Adequacy of susceptibility testing, and any change in the frequencies of isolated species were also analyzed . The results showed that only 20% and 30% of hospitals tested the piperacillin-tazobactam and cefoxitin susceptibility of Enterobacteriaceae, respectively, only 24% of hospitals the piperacillin-tazobactam susceptibility of P . aeruginosa, and 17% of hospitals the fusidic acid susceptibility of staphylococci . Among the isolates 26.3% were glucose-nonfermenting gram-negative bacilli, and 34.7% of Enterococcus were Enterococcus faecium . Slight decline of cefotaxime-resistance rate to 20% was noted in Klebsiella pneumoniae, while fluoroquinolone-resistance rate was 68% in Acinetobacter baumannii . The ceftazidime- and imipenem-resistance rates were 17% and 18%, respectively in P . aeruginosa . The vancomycin-resistance rate of E . faecium rose significantly to 15.1%, but the rates varied significantly depending on hospitals suggesting presence of different degree of selective pressure or nosocomial spread . In conclusion, the prevalence of imipenem-resistant P . aeruginosa and the increase of vancomycin-resistant E . faecium were the particularly worrisome phenomena observed in this study. Neurol India, 2001 Jun, 49(2), 134 - 7 Nosocomial infections due to Acinetobacter baumannii in a neurosurgery ICU; Gulati S et al.; Invasive infections caused by Acinetobacter baumannii in a post-operative neurosurgery ICU were studied . Sixty one patients admitted during a span of 11 months were culture positive for acinetobacter species from blood and/or CSF samples . They were followed up prospectively for evidence of infection and clinical outcome . 40 cases had clinical evidence of infection due to acinetobacter species while in 21 patients, the isolation of the organism was considered a contaminant . Acinetobacter baumannii was the most common organism associated with invasive infections . Respiratory tract was found to be the most common primary source of infection in patients with bacteraemia or meningitis . The age, sex and pre-operative hospital stay were not significantly different in the two groups (p>0.05), while post-operative hospital stay and mortality was significantly higher in patients with invasive infection (p<0.05) . Acinetobacter baumannii was isolated from multiple sites (p<0.05) and repeatedly from the same site (p<0.001) in a significantly higher number of patients with invasive infections . Mortality was high in the patients infected with Acinetobacter baumannii . Even amongst the infected group, the patient shaving meningitis showed a higher mortality as compared to the patients having bacteraemia. Clin Experiment Ophthalmol, 2001 Jun, 29(3), 153 - 6 Random amplified polymorphic DNA analysis of Acinetobacter species isolated from worn contact lenses; Corrigan KM et al.; The purpose of this study was to explore the genotypes of Acinetobacter species and to compare the genotypes and phenotypes of the Acinetobacter isolated from contact lens wearers . Nineteen strains were used in the study, 13 were isolated from patients experiencing an adverse response event, and six strains were isolated from asymptomatic contact lens wearers . Random amplified polymorphic DNA and phenotypic analyses were carried out using commercially available kits . Random amplified polymorphic DNA analysis showed a higher discrimination power compared with the phenotypic analysis . The test strains were loosely clustered into six genotypic groups with no definite relation to any clinical events . These results indicate that many genotypes of Acinetobacter can cause adverse responses, and the initial source of the microorganisms rather than their clinical sequelae may determine classification. Clin Experiment Ophthalmol, 2001 Jun, 29(3), 150 - 2 Production of N-acyl homoserine lactones by gram-negative bacteria isolated from contact lens wearers; Zhu H et al.; The purpose of this study was to investigate the production of N-acyl-homoserine lactone (AHL) signal molecules in ocular gram-negative bacteria . A total of 91 ocular strains isolated from contact lens adverse response patients and asymptomatic subjects were used in the study . These included Acinetobacter, Aeromonas hydrophila, Escherichia coli, Haemophilus influenzae, Klebsiella oxytoca, Pseudomonas aeruginosa, Serratia liquefaciens, Serratia marcescens, and Stenotrophomonas maltophilia . The biosensor strains Chromobacterium violaceum mutant CV026 and Agrobacterium tumefaciens A136 were used for detection of AHL signal molecules . The majority of A . hydrophila, P . aeruginosa, and S . liquefaciens strains produced more than one AHL molecule . Serratia marcescens strains were AHL positive only under detection of A136 . The rest of the test species did not show any AHL production under the current detection system . These findings indicate that AHL-mediated quorum-sensing systems are present in some of the ocular bacteria, and the different signal molecules may be involved with the quorum-sensing pathway in the other bacterial species. FEMS Microbiol Lett, 2001 Jul 10, 201(1), 15 - 9 Spontaneous mutations affecting transcriptional regulation by protocatechuate in Acinetobacter; D'Argenio DA et al.; Positive selection yields Acinetobacter strains with a spontaneous mutation blocking catabolism of protocatechuate . For this study, the growth temperature during selection was lowered to 22 degrees C: growth at 37 degrees C was found to mask the role of the protocatechuate-responsive transcriptional regulator PcaU . The resulting mutants included those with amino acid substitutions useful for understanding PcaU structure and function, a 20-bp deletion whose repeated isolation suggested genetic instability of DNA in the putative PcaU operator, and a large deletion whose phenotype revealed that the supraoperonic cluster of genes for the protocatechuate branch of the beta-ketoadipate pathway extends to genes for the utilization of C(6)-C(10) straight-chain dicarboxylic acids including adipate. J Med Microbiol, 2001 Jul, 50(7), 642 - 5 Clinical importance of extended-spectrum beta-lactamase (PER-1-type)-producing Acinetobacter spp . and Pseudomonas aeruginosa strains; Vahaboglu H et al.; Recently, an extended-spectrum beta-lactamase (PER-1) was found to be disseminated among Acinetobacter spp . and Pseudomonasaeruginosa isolates in Turkey . A population-based cohort study was conducted to elucidate predictive mortality factors in patients with nosocomial infections caused by Acinetobacter spp . and P . aeruginosa, with particular reference to PER-1-type extended-spectrum beta-lactamase (ESBL) production . The study group comprised 16 and 21 non-survivors and 82 and 126 survivors in cohorts infected with Acinetobacter and P . aeruginosa, respectively . In the Acinetobacter-infected cohort, nosocomial pneumonia, hypotension and infection with a PER-positive isolate were independent predictors of mortality . In the P . aeruginosa-infected cohort, impaired consciousness, a PER-positive isolate, male sex and (with a negative relative risk) urinary tract infection were independent predictors of death . This study demonstrated the relationship of PER-1-type ESBL-producing Acinetobacter spp . and P . aeruginosa with poor clinical outcome. Clin Microbiol Infect, 2001 Jun, 7(6), 308 - 15 Resistance to antibiotics and biocides among non-fermenting Gram-negative bacteria; Higgins CS et al.; OBJECTIVE: To investigate the antibiotic and biocide susceptibilities of clinical isolates of rarely encountered Gram-negative, non-fermenting bacteria . METHODS: Thirty Gram-negative non-fermenting bacterial strains were isolated from blood cultures of oncology patients . These were studied for their resistance to 11 antibiotics . Their susceptibilities to seven biocides used in hospitals were also examined . RESULTS: Isolates of Stenotrophomonas maltophilia and Ochrobactrum anthropi were generally resistant to at least five of the antibiotics, whereas isolates of Comamonas acidivorans, Flavobacterium oryzihabitans, Aeromonas hydrophila, Sphingobacterium spiritivorum, Acinetobacter junii and Acinetobacter lwoffi were generally sensitive to at least nine of the antibiotics . Trovafloxacin and trimethoprim-sulfamethoxazole were the most effective antibacterial agents tested, with 0% and 7%, respectively, of isolates being resistant, whereas 63% of isolates were resistant to aztreonam . Some isolates, sensitive to meropenem and/or ceftazidime in vitro, possessed very high MBC/MIC ratios for these beta-lactams . Two out of three biocides used in hospital pharmacies showed lethal activity towards all strains tested when used at less than one-third of their recommended in-use concentration . Proceine 40 failed to give a 5 log reduction in bacterial cell number for the isolates tested when used at its "in-use" concentration . A concentration of > 500 mg/L chlorhexidine was required to achieve a 5 log reduction for the same isolates . CONCLUSIONS: We have examined the antibiotic susceptibilities of non-fermenting Gram-negative bacterial strains isolated from immunocompromised patients . Despite being sensitive to certain antibiotics in vitro, some isolates were still able to cause serious bacteremia . We have also reported for the first time the susceptibilities of non-fermenting Gram-negative bacteria to common biocides used in hospital infection control, and have shown that some strains are able to persist at the "in-use" concentration of particular biocides . It is therefore important to study further this particular group of organisms, and, in particular, to examine whether there exists a link between resistance to antibiotics and resistance to biocides. J Hosp Infect, 2001 Jul, 48(3), 228 - 32 Investigation of an outbreak of multi-drug resistant Acinetobacter baumannii in an intensive care burns unit; Roberts SA et al.; Over a three month period there was an outbreak of infection, due to a multi-drug resistant Acinetobacter baumannii in the intensive care burns unit with spread of infection to other patients, both within the unit and elsewhere in the hospital.Microbiological sampling of the environment and of the healthcare workers' (HCWs) hands were carried out . Strain relatedness of the isolates was confirmed by pulsed field gel electrophoresis.Fifteen patients were involved in the outbreak, whose infections were all hospital-acquired . The burns room environment was contaminated with the A . baumannii, as was the door handle of the door leading from the ante-chamber between both rooms . This allowed the hands of HCWs to be contaminated by A . baumannii despite appropriate handwashing procedures prior to leaving the rooms . Two staff members were colonized with A . baumannii . One HCW who was directly involved in patient care was found to be "heavily" colonized, the other, with less patient contact, was only "lightly" colonized . Review of handwashing practices revealed that chlorhexidine/alcohol hand wash solution was not used by the HCW whose hands were heavily colonized.A combination of a review of handwashing practice, education about the spread of bacteria via hands and contaminated environment, and the revision of infection control procedures in the unit contributed to a prompt termination of the outbreak . J Org Chem, 2001 Feb 9, 66(3), 733 - 8 Asymmetric Baeyer-Villiger oxidations of 4-mono- and 4,4-disubstituted cyclohexanones by whole cells of engineered Escherichia coli; Mihovilovic MD et al.; Whole cells of an Escherichia coli strain that overexpresses Acinetobacter sp . NCIB 9871 cyclohexanone monooxygenase have been used for the Baeyer-Villiger oxidations of a variety of 4-mono- and 4,4-disubstituted cyclohexanones . In cases where comparisons were possible, this new biocatalytic reagent provided lactones with chemical yields and optical purities that were comparable to those obtained from the purified enzyme or a strain of bakers' yeast that expresses the same enzyme . The efficient production of cyclohexanone monooxygenase in the E . coli expression system (ca . 30% of total soluble protein) allowed these oxidations to reach completion in approximately half the time required for the engineered bakers' yeast strain . Surprisingly, 4,4-disubstituted cyclohexanones were also accepted by the enzyme, and the enantioselectivities of these oxidations could be rationalized by considering the conformational energies of bound substrates along with the enzyme's intrinsic enantioselectivity . The enzyme expressed in E . coli cells also oxidized several 4-substituted cyclohexanones bearing polar substituents, often with high enantioselectivities . In the case of 4-iodocyclohexanone, the lactone was obtained in > 98% ee and its absolute configuration was assigned by X-ray crystallography . The crystal belongs to the monoclinic P2(1) space group with a = 5.7400(10), b = 6.1650(10), c = 11.377(2) A, b = 99.98(2) degrees, and Z = 2 . Taken together, these results demonstrate the utility of an engineered bacterial strain in delivering useful chiral building blocks in an experimentally simple manner. Microbiology, 2001 Jul, 147(Pt 7), 1937 - 46 Analysis of the wee gene cluster responsible for the biosynthesis of the polymeric bioemulsifier from the oil-degrading strain Acinetobacter lwoffii RAG-1; Nakar D et al.; A cluster (27 kbp) of genes responsible for the biosynthesis of the amphipathic, polysaccharide bioemulsifier emulsan from the oil-degrading Acinetobacter lwoffii RAG-1 was isolated and characterized . The complete sequence of this cluster, termed wee, consisted of 20 ORFs . One set of 17 ORFs was transcribed in one direction, while a second set of three ORFs, 607 bp upstream of the first, was transcribed in the opposite direction . Mutations in either of the two regions caused defects in emulsan production, yielding specific activities of 5-14% of parental emulsifying activity . Putative functions could be assigned to proteins involved in production of nucleotide amino sugar precursors, transglycosylation, transacetylation, polymerization and transport . However, no JUMPstart or ops sequences, normally found associated with some polysaccharide biosynthetic gene clusters, were identified . Evidence is presented suggesting that the bioemulsifier may be a member of the group 1 or group 4 polysaccharides. Transpl Infect Dis, 2000 Sep, 2(3), 133 - 9 Significant post-transplant hypogammaglobulinemia in six heart transplant recipients: an emerging clinical phenomenon? Corales R, Chua J, Mawhorter S, Young JB, Starling R, Tomford JW, McCarthy P, Braun WE, Smedira N, Hobbs R, Haas G, Pelegrin D, Majercik M, Hoercher K, Cook D, Avery RK. BACKGROUND: The recent development of powerful agents such as mycophenolate mofetil and tacrolimus has altered current regimens for the prevention and treatment of allograft rejection . Questions have been raised about these newer regimens in terms of susceptibility to opportunistic infections and effects on host defenses . Severe hypogammaglobulinemia has been infrequently described in solid organ transplant recipients, but has been recently noted in six heart transplant recipients at one center, of whom five were receiving a combination of tacrolimus, mycophenolate mofetil, and prednisone . METHODS: Case summaries of six recent heart transplant recipients with total immunoglobulin G (IgG) levels of less than 310 mg/dl, five of whom had cytomegalovirus (CMV) infection and three of whom had multiple infections including Nocardia, invasive Trichophyton, and Acinetobacter bacteremia . Previous literature was reviewed with the aid of a Medline search using the search terms hypogammaglobulinemia; kidney, liver, heart, lung, and organ transplantation; mycophenolate mofetil; tacrolimus; cyclosporine; azathioprine; and nocardiosis . RESULTS: We here report six cardiac transplant recipients seen over a period of one year who were found to have immunoglobulin G levels of 310 mg/dl or below (normal: 717-1400 mg/dl) . The first five patients were diagnosed because of evaluation for infections; the sixth, who was asymptomatic with an IgG level of 175, was found during screening for hypogammaglobulinemia instituted as a result of these first five patients . All six patients had received steroid pulses for rejection; all received mycophenolate mofetil; and 5/6 had been switched from cyclosporine to tacrolimus because of steroid-resistant rejection . Transient neutropenia (absolute neutrophil count less than 1000) was observed in 2/6; 3/6 had received OKT3 therapy for refractory rejection . These six patients were treated with a combination of antimicrobials, immunoglobulin replacement, and decrease in immunosuppressive therapy . CONCLUSION: The finding of unexpected hypogammaglobulinemia and concomitant infectious complications in six heart transplant recipients highlights a possible complication in a subset of patients receiving newer immunosuppressive agents . A larger prospective study is underway to determine risk factors for development of post-transplant hypogammaglobulinemia and to assess pre-transplant immune status of these recipients . Monitoring of immunoglobulin levels in high-risk patients receiving intensified immunosuppressive therapy for rejection may help to prevent infectious complications. Infect Control Hosp Epidemiol, 2001 May, 22(5), 284 - 8 Antibiotic resistance is a major risk factor for epidemic behavior of Acinetobacter baumannii; Koeleman JG et al.; OBJECTIVE: To study the presence of bacterial factors in clinical isolates of Acinetobacter species in order to identify markers of epidemic potential . DESIGN: Case-control study . METHODS: Forty-six isolates of Acinetobacter species, including 23 epidemic and 23 sporadic strains from different outbreaks in nine European countries, were compared for the presence of the following factors: hemagglutination, presence of capsules and fimbriae, binding to salivary mucins, resistance to drying, and antibiogram typing . Genotyping of all strains was performed by amplified fragment-length polymorphism (AFLP) . RESULTS: All outbreak strains except two (91%) were identified as Acinetobacter baumannii . Binding to salivary mucins and resistance to antibiotics were significantly associated with epidemic behavior . Antibiogram typing showed clustering of predominantly A baumannii strains within one group, and these strains were significantly more resistant to antibiotics than sporadic strains . AFLP genotyping revealed a great heterogeneity among the different European Acinetobacter strains . Cluster analysis of AFLP fingerprints showed several small clusters of different A baumannii outbreak strains . AFLP genotyping could not identify a common epidemic marker within the strains studied . CONCLUSIONS: Antibiogram typing can be used in routine clinical laboratories as a screening method to recognize potentially epidemic A baumannii strains . Several other factors were found, both in different outbreaks as well as in sporadic Acinetobacter isolates . These characteristics were unable to predict epidemic behavior and therefore cannot be used as discriminative epidemic markers . AFLP genotyping demonstrated no common clonal origin of European epidemic A baumannii strains . This indicates that any clinical A baumannii isolate with resistance to multiple antibiotics can be a potential nosocomial outbreak strain. J Clin Microbiol, 2001 Jul, 39(7), 2576 - 80 O-antigen diversity among Acinetobacter baumannii strains from the Czech Republic and Northwestern Europe, as determined by lipopolysaccharide-specific monoclonal antibodies; Pantophlet R et al.; O-antigen-specific monoclonal antibodies (MAbs) are currently being generated to develop an O-serotyping scheme for the genus Acinetobacter and to provide potent tools to study the diversity of O-antigens among Acinetobacter strains . In this report, Acinetobacter baumannii strains from the Czech Republic and from two clonal groups identified in Northwestern Europe (termed clones I and II) were investigated for their reactivity with a panel of O-antigen-specific MAbs generated against Acinetobacter strains from various species . The bacteria were characterized for their ribotype, biotype, and antibiotic susceptibility and the presence of the 8.7-kb plasmid pAN1 . By using the combination of these typing profiles, the Czech strains could be classified into four previously defined groups (A . Nemec, L . Janda, O . Melter, and L . Dijkshoorn, J . Med . Microbiol . 48:287-296, 1999): two relatively homogeneous groups of multiresistant strains (termed groups A and B), a heterogeneous group of other multiresistant strains, and a group of susceptible strains . O-antigen reactivity was observed primarily with MAbs generated against Acinetobacter calcoaceticus and Acinetobacter baumannii strains . A comparison of reaction patterns confirmed the previously hypothesized clonal relationship between group A and clone I strains, which are also similar in other properties . The results show that there is limited O-antigen variability among strains with similar geno- and phenotypic characteristics and are suggestive of a high prevalence of certain A . baumannii serotypes in the clinical environment . It is also shown that O-antigen-specific MAbs are useful for the follow-up of strains causing outbreaks in hospitals. Clin Diagn Lab Immunol, 2001 Jul, 8(4), 825 - 7 Generation and serological characterization of murine monoclonal antibodies against O antigens from Acinetobacter reference strains; Pantophlet R et al.; O-antigen-specific monoclonal antibodies were generated against Acinetobacter strains from international type culture collections and characterized by enzyme immunoassay and Western and colony blotting . The antibodies aid in the further completion of an O-serotyping scheme for Acinetobacter and, due to their high specificity, are especially useful to all working with these strains. FEMS Microbiol Lett, 2001 Jun 25, 200(2), 247 - 52 Protein synthesis patterns in Acinetobacter calcoaceticus induced by phenol and catechol show specificities of responses to chemostress; Benndorf D et al.; The proteins induced in Acinetobacter calcoaceticus by the potentially toxic growth substrates phenol and catechol were analyzed by 2D-electrophoresis of cell extracts and compared with those induced by heat shock and oxidative stress . Although both aromatic compounds are quite similar, the only difference being that catechol has an additional hydroxyl group, the responses obtained differed considerably . Phenol has greater lipophilicity and mainly induced heat shock proteins, whereas catechol, which causes the production of reactive oxygen species, predominantly induced oxidative stress proteins . Furthermore, some special proteins were induced by phenol or catechol, which might be useful as biomarkers for chemostress, and could be involved in the catalytic degradation of potentially toxic compounds. Electrophoresis, 2001 May, 22(9), 1705 - 11 Media containing aromatic compounds induce peculiar proteins in Acinetobacter radioresistens, as revealed by proteome analysis; Giuffrida MG et al.; An Acinetobacter radioresistens strain able to grow on phenol or benzoate as sole carbon and energy source through the beta-ketoadipate pathway was isolated in our laboratories . In previous research, we found a different expression of catechol-1,2-dioxygenase isoenzymes (C-1,2-O) depending on the growth substrate (phenol or benzoate) . In the present study, we used proteome techniques to extend our investigation to other enzymes involved in the aromatic degradation pathway . Since the first nontoxic metabolite in this route is cis,cis-muconic acid, we focused our attention on the enzymes leading to this compound, chiefly phenol hydroxylase (PH), benzoate dioxygenase (BD), cis-1,2-dihydroxycyclohexa-3,5-diene-1-carboxylate dehydrogenase (D) and C-1,2-O . In particular, the A . radioresistens proteome was monitored under different growth substrate conditions, using acetate, benzoate, or phenol as sole carbon source . We compared the protein maps by software image analysis and detected marked differences, suggesting the inducibility of most enzymes . This research also sought to evaluate the conditions allowing the best expression of enzymes to be used in immobilized systems suitable for bioremediation . The experimental data indicate that benzoate is the best carbon source to gain the highest amount of C-1,2-O and D, while phenol is the best growth substrate to obtain PH. Microbios, 2001, 105(412), 153 - 61 A new extraction method for Acinetobacter species ODB-L2 rough form lipopolysaccharide from culture broth; Kunii K et al.; The Gram-negative bacterium Acinetobacter species ODB-L2 produces lipopolysaccharide (LPS) in culture broth . The LPS could not be purified by conventional extraction methods using 90% phenol/water or 90% phenol/chloroform/petroleum ether mixed solvent . Extraction was achieved employing an admixture of chloroform, ethanol, and 4 M HCI solution . The LPS was purified from dissolving the crude extracts in 90% phenol and LPS sediment formed by addition of methanol . The LPS was characterized by chemical, biochemical, and physicochemical methods as rough form 3-hydroxydodecanoic acid rich LPS. Cornea, 2001 Jul, 20(5), 463 - 6 Association of acinetobacter species with contact lens-induced adverse responses; Corrigan KM et al.; PURPOSE: To determine the levels of Acinetobacter species associated with normal soft contact lens wear and to determine whether Acinetobacter species are involved in adverse reactions that occur during contact lens wear . METHODS: Patients wore soft contact lenses on an extended-wear basis . The bacteria on lenses and ocular swabs during asymptomatic and symptomatic lens wear were identified using standard microbiologic methods . RESULTS: Acinetobacter species were isolated and identified from 16 (13%) of 126 patient samples . Greater numbers of Acinetobacter species were isolated from lenses of patients experiencing adverse responses than from asymptomatic patients.Acinetobacter species were isolated from patients experiencing symptomatic adverse responses in 4 (13%) of 32 cases . CONCLUSION: It appeared that Acinetobacter species colonized the eye of extended contact lens wearers at a time when the normal functioning of the eye was compromised by contact lens wear . When Acinetobacter species were in high numbers on a contact lens, an adverse response occurred . This may implicate Acinetobacter species as a contributing factor to adverse responses associated with contact lens wear. Diagn Microbiol Infect Dis, 2001 Apr, 39(4), 215 - 23 Efficacy of two DNA fingerprinting methods for typing Acinetobacter baumannii isolates; Quelle LS et al.; Performance of macrorestriction and repetitive extragenic palindromic DNA sequence-based PCR (REP-PCR) to type Acinetobacter baumannii isolates was quantitatively estimated using a test population of 54 outbreak-related, 29 endemic infection-related and 17 epidemiologically-unrelated isolates . Reproducibility and stability for macrorestriction were 100%, and REP-PCR showed only slightly lower stability . Macrorestriction resolved 18 fingerprints and REP-PCR 10 DNA patterns, forming eight and seven clusters at 75% of similarity level, respectively . Intercluster band variation was > 7 bands for both methods . Although, all endemic isolates, except one, were concordantly grouped by both methods, macrorestriction distinguished a greater number of subtypes over one year study . For outbreaks, the epidemiologic concordance for both methods was 88% . The discriminatory index for macrorestriction and REP-PCR was 0.884 and 0.877, respectively . In conclusion, both methods showed similar efficacy as epidemiological markers, and by concordance, this study demonstrated that for REP-PCR typing, a > or = 7 bands difference seemed an appropriate threshold to identify unrelated strains. J Biol Chem, 2001 Sep 14, 276(37), 34465 - 72 Epub 2001 Jun 14. Xyloside transport by XylP, a member of the galactoside-pentoside-hexuronide family; Heuberger EH et al.; This paper describes the functional characterization of the xyloside transporter, XylP, of Lactobacillus pentosus with the aid of a spectroscopy-based assay system . In order to monitor the transport reaction, the natural xyloside isoprimeverose, a building block of hemicellulose, and the analogue methyl-isoprimeverose were chemically synthesized by a new and efficient procedure . The XylP protein was purified by metal affinity chromatography, following high level expression in Lactococcus lactis from the nisin-inducible promoter . The purified XylP protein was incorporated into liposomes, in which the glucose dehydrogenase from Acinetobacter calcoaceticus (sGDH) was entrapped . sGDH can oxidize aldose sugars in the presence of dichlorophenol-indophenol as electron acceptor . The coupled assay thus involves XylP-mediated isoprimeverose uptake followed by internal oxidation of the sugar by sGDH, which can be monitored from the reduction of 2,6-dichlorophenol-indophenol at 600 nm . The uptake of isoprimeverose was stimulated by the presence of the non-oxidizable methyl-isoprimeverose on the trans-side of the membrane, indicating that exchange transport is faster than unidirectional downhill uptake . Unlike other members of the galactoside-pentoside-hexuronide family, XylP does not transport monosaccharides (xylose) but requires a glycosidic linkage at the anomeric carbon position . Consistent with a proton motive force-driven mechanism, the uptake was stimulated by a membrane potential (inside negative relative to outside) and inhibited by a pH gradient (inside acidic relative to outside) . The advantages of the here-described transport assay for studies of carbohydrate transport are discussed. Chemotherapy, 2001 Jul-Aug, 47(4), 304 - 8 Evaluation of spontaneous contamination of ocular medications; Marchese A et al.; BACKGROUND: In order to evaluate whether single-dose ophthalmic preparations in 0.5-ml containers can safely be used within 24 h after the first opening, eigth different sterile ocular medications containing timolol, jaluronic acid, diclofenac, ketotifen, pilocarpine, formocortal, formocortal-gentamycin, and tetryzoline-feniramine (Farmigea, Italy) were opened and tested for spontaneous bacterial contamination after exposure to air . METHODS: Samples (10 microl) were collected from exposed ophthalmic preparations after 0, 2, 4, 8 and 24 h . RESULTS: No viable microorganisms were detected during and at the end of the evaluation period . In order to assess whether the resident or pathogenic ocular bacterial population due to repeated handling might contaminate the medications, about 10(5) cells of different species (Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus pneumoniae, Streptococcus spp., Corynebacterium spp., Pseudomonas aeruginosa, Neisseria spp., Acinetobacter spp., Haemophilus influenzae, Escherichia coli and Candida albicans) were added to the containers and incubated at 37 degrees C or at room temperature . Samples were collected and the number of viable bacteria was estimated . The antibacterial effect of the ophthalmic compounds varied depending on the species considered . Tetryzoline-feniramine, pilocarpine, ketotifen and formocortal-gentamycin exhibited a frank bactericidal activity (<100 survivors after 18-24 h of exposure) against the great majority of the species tested . CONCLUSION: These results indicate that the risk of spontaneous contamination of ophthalmic preparations after their first opening is low, and that all preparations tested exhibit an aspecific antibacterial activity . As a consequence, the safe usage of these ocular medications could be extended from the recommended 3 h to at least 24 h after the first usage. Syst Appl Microbiol, 2001 Apr, 24(1), 122 - 30 Comparison of the antimicrobial tolerance of oxytetracycline-resistant heterotrophic bacteria isolated from hospital sewage and freshwater fishfarm water in Belgium; Huys G et al.; The aim of this study was to investigate the relationship between antimicrobial tolerance and taxonomic diversity among the culturable oxytetracycline-resistant (Ot(r)) heterotrophic bacterial population in two Belgian aquatic sites receiving wastewater either from human medicine or from aquaculture . The study of Ot(r) heterotrophs and mesophilic Aeromonas spp . allowed comparison of tolerance data at the intergenus as well as at the intragenus level . In total, 354 independently obtained Ot(r) isolates were subjected to antimicrobial tolerance testing and identified by GLC analysis of their cellular fatty acid methyl esters (FAMEs), by API 20E profiling and/or by Fluorescent Amplified Fragment Length Polymorphism (FAFLP) DNA fingerprinting . In general, Ot(r) hospital heterotrophs displayed a higher frequency (84%) of ampicillin (Amp) tolerance compared to the Ot(r) heterotrophs from the freshwater fishfarm site (22%) . FAME results indicated that this effect was linked to the predominance of intrinsically ampicillin-resistant Ot(r) Aeromonas strains over representatives of Acinetobacter and Escherichia coli within the hospital strain set . Among the Ot(r) mesophilic Aeromonas strain set, the global tolerance profiles of the two sites only differed in a higher number of kanamycin (Kan) -tolerant strains (43%) for hospital aeromonads in comparison with the fishfarm aeromonads (8%) . To some extent, this finding was correlated with the specific presence of Aeromonas caviae DNA hybridisation group (HG) 4 . Collectively, these results suggest that the profiles for Amp and Kan tolerance observed in both sites arose from taxonomic differences in the culturable Ot(r) bacterial population at the generic or subgeneric level . In addition, our identification data also revealed that Enterobacter sp., Stenotrophomonas maltophilia, and A . veronii biovar sobria HG8 may be considered potential indicator organisms to assess microbial tolerance in various compartments of the aquatic environment. Curr Microbiol, 2001 Jun, 42(6), 408 - 14 Photoinactivation of Acinetobacter baumannii and Escherichia coli B by a cationic hydrophilic porphyrin at various light wavelengths; Nitzan Y et al.; Photodynamic treatment by the cationic TMPyP photosensitizer was undertaken on the multiple antibiotic-resistant bacteria Acinetobacter baumannii and Escherichia coli . Total eradication of the bacterial cultures was determined immediately after initiation of illumination when these bacteria were treated with 5, 10, 15, 20-tetra (4-N methylpyridyl)porphine (TMPyP) at a concentration of 29.4 micromol/L and illuminated by blue, green, or red light . Total eradication of both bacteria was obtained also after treatment of bacterial cultures with 3.7 micromol/L TMPyP and illumination with blue light (400-450 nm) . On the other hand, an 8- or 16- to 20-fold higher light intensity, respectively, was required for total eradication upon illumination with green (480-550 nm) or red light (600-700 nm) . A 407-nm blue light only 7 and 9 joules/cm2, respectively, was needed for total eradication of both bacteria even at a concentration of 3.7 micromol/L TMPyP . X-ray-linked microanalysis demonstrated loss of potassium and a flood of sodium and chloride into the cells, indicating serious damage to the cytoplasmic membrane . Transmission electron microscopy (TEM) revealed structural changes and damage to the membrane of treated E . coli . In A . baumannii-treated cells, mesosomes and black dots that resemble aggregation of polyphosphate polymers could be seen . DNA breakage appeared only after a long period of illumination, when the bacterial cell was no longer viable . It can be concluded that cytoplasmic membrane damage and not DNA breakage is the major cause for bacterial death upon photosensitization. Appl Environ Microbiol, 2001 Jun, 67(6), 2507 - 14 Cloning and expression of the benzoate dioxygenase genes from Rhodococcus sp . strain 19070; Haddad S et al.; The bopXYZ genes from the gram-positive bacterium Rhodococcus sp . strain 19070 encode a broad-substrate-specific benzoate dioxygenase . Expression of the BopXY terminal oxygenase enabled Escherichia coli to convert benzoate or anthranilate (2-aminobenzoate) to a nonaromatic cis-diol or catechol, respectively . This expression system also rapidly transformed m-toluate (3-methylbenzoate) to an unidentified product . In contrast, 2-chlorobenzoate was not a good substrate . The BopXYZ dioxygenase was homologous to the chromosomally encoded benzoate dioxygenase (BenABC) and the plasmid-encoded toluate dioxygenase (XylXYZ) of gram-negative acinetobacters and pseudomonads . Pulsed-field gel electrophoresis failed to identify any plasmid in Rhodococcus sp . strain 19070 . Catechol 1,2- and 2,3-dioxygenase activity indicated that strain 19070 possesses both meta- and ortho-cleavage degradative pathways, which are associated in pseudomonads with the xyl and ben genes, respectively . Open reading frames downstream of bopXYZ, designated bopL and bopK, resembled genes encoding cis-diol dehydrogenases and benzoate transporters, respectively . The bop genes were in the same order as the chromosomal ben genes of P . putida PRS2000 . The deduced sequences of BopXY were 50 to 60% identical to the corresponding proteins of benzoate and toluate dioxygenases . The reductase components of these latter dioxygenases, BenC and XylZ, are 201 residues shorter than the deduced BopZ sequence . As predicted from the sequence, expression of BopZ in E . coli yielded an approximately 60-kDa protein whose presence corresponded to increased cytochrome c reductase activity . While the N-terminal region of BopZ was approximately 50% identical in sequence to the entire BenC or XylZ reductases, the C terminus was unlike other known protein sequences. J Environ Monit, 2001 Feb, 3(2), 206 - 9 Suspended particulates and bioaerosols emitted from an agricultural non-point source; Hameed AA et al.; Suspended particulate and bioaerosol levels were measured at three sites downwind of an agricultural non-point source during the wheat harvesting season . Suspended particulates were detected at mean values ranging from 10000 to 2420 micrograms m-3 at distances of from 20 to 60 m downwind of the source, respectively . Airborne viable bacterial counts were recorded at mean values ranging between 10(4) and 10(6) colony forming units (cfu) m-3, whereas, Gram negative (Gram -ve) bacteria varied between 10(3) and 10(5) cfu m-3 . Fungi levels were detected at mean values varying between 10(5) and 10(6) cfu m-3 . However, streptomycetes were found at lower counts than those recorded for viable bacteria and fungi . Total viable bacteria, Gram -ve bacteria, fungi and streptomycetes associated hay fragments were determined at mean values of 1.5 x 10(6), 1.6 x 10(3), 2.2 x 10(4) and 6 x 10(3) cfu g-1 of hay, respectively . Cladosporium, white and red yeasts as well as Alternaria were the predominant airborne fungi, whereas, Alternaria was the dominant species associated with hay fragments . Pseudomonas, Acinetobacter and Enterobacteriaceae were the dominant Gram -ve bacteria . The most common fungal genera, such as Cladosporium and Fusarium (minor short axis), as well as Streptomyces species have an aerodynamic diameter (dae) of less than 5 microns, which can penetrate and deposit in the alveoli . Farmers and nearby residents are exposed to high levels of organic dust and bioaerosols during the wheat harvesting season . This may cause health problems in exposed persons based on toxic or allergic reactions. Biochem Biophys Res Commun, 2001 Apr 13, 282(4), 899 - 903 ESI- and MALDI-MS analysis of cyclohexanone monooxygenase from acinetobacter NCIB 9871; Kneller MB et al.; Recombinant and native forms of cyclohexanone monooxygenase (CMO) from Acinetobacter NCIB 9871 were analyzed by mass spectrometry to probe ambiguities arising from the presence of multiple DNA sequences for the enzyme in GenBank . A CMO gene corresponding exactly to the nucleotide sequence described by Iwaki et al . (10) was amplified from genomic DNA, cloned into pET15b, and the recombinant protein purified from a bacterial expression system . Electrospray mass spectrometry of both the recombinant material and the native form of CMO isolated from Acinetobacter yielded molecular weights within 0.01% of those predicted from the translated gene sequence of Iwaki et al . (10) . Trypsin and chymotrypsin digests of native CMO, analyzed by electrospray and MALDI mass spectrometry, provided greater than 97% coverage of the protein and confirmed the presence of specific peptide sequences predicted by the Iwaki sequence alone . Therefore, the primary sequence of native Acinetobacter CMO is identical to the gene sequence for chnB deposited under accession number AB006902 . Environ Sci Technol, 2001 Feb 1, 35(3), 528 - 34 Response of sediment bacterial assemblages to selenate and acetate amendments; Lucas FS et al.; We followed the response of bacterial assemblages in slurries of estuarine sediments to amendments of 100 microM sodium selenate and 10 mM sodium acetate . Selenate was removed from the dissolved phase in all slurries after an initial lag that varied depending on the source of th