PMID(sorted ascending)
antibacterial in vitro-activity of meropenem against 200 clinical isolates in comparison to 11 selected antibiotics.the antimicrobial activity of meropenem, a new parenteral carbapenem, was tested in vitro by an agar dilution method against 200 clinical isolates (gram-negative/positive aerobes and anaerobes). meropenem was compared with imipenem, ceftazidime, cefotaxime, piperacillin, ciprofloxacin, gentamicin; and metronidazole, cefoxitin, chloramphenicol, clindamycin, vancomycin when appropriate. meropenem and imipenem exhibited an extended spectrum of activity with low minimal inhibitory concentrations (mi ...19921303691
a 24-amino-acid polypeptide is essential for the biosynthesis of the coenzyme least four genes are required for the biosynthesis of the coenzyme pyrrolo-quinoline-quinone (pqq) in acinetobacter calcoaceticus. the dna region where one of these genes was mapped codes for a polypeptide of only 24 amino acids. here we show that indeed this small peptide is essential for pqq synthesis. site-directed mutagenesis shows that at least one glutamate and one tyrosine residue of the polypeptide are essential for its function.19921310505
nucleotide sequence and structure of the klebsiella pneumoniae pqq operon.a 6940 bp klebsiella pneumoniae chromosomal dna fragment, containing genes involved in pyrroloquinoline quinone (pqq) biosynthesis, was sequenced. six open reading frames, pqqa, pqqb, pqqc, pqqd, pqqe and pqqf were identified in the pqq operon, which coded for polypeptides of 2764 (23 amino acids), 33,464, 28,986, 10,436, 42,881 and 83,616 da, respectively. the transcription startpoint was mapped by primer extension analysis, upstream of pqqa, and promoter boxes could be identified. the gene pro ...19921313537
plasmid profiles of acinetobacter and enterobacter species of hospital origin: restriction endonuclease analysis of plasmid dna and transformation of escherichia coli by r plasmids.a total of 37 multi-resistant strains (20 acinetobacter calcoaceticus and 17 enterobacter cloacae) were isolated from patients of the intensive care units. all the isolates were examined for resistance to a battery of antimicrobial agents by the disk diffusion method. plasmid profiles and restriction endonuclease analysis of plasmid dna by ecor1 revealed the spread of one a. calcoaceticus and two e. cloacae endemic strains. transformation experiments on escherichia coli competent cells by three ...19921321240
acli, a new restriction endonuclease from acinetobacter calcoaceticus recognizing 5'-a decreases cgtt-3'. 19921322531
cloning of an erwinia herbicola gene necessary for gluconic acid production and enhanced mineral phosphate solubilization in escherichia coli hb101: nucleotide sequence and probable involvement in biosynthesis of the coenzyme pyrroloquinoline quinone.escherichia coli is capable of synthesizing the apo-glucose dehydrogenase enzyme (gdh) but not the cofactor pyrroloquinoline quinone (pqq), which is essential for formation of the holoenzyme. therefore, in the absence of exogenous pqq, e. coli does not produce gluconic acid. evidence is presented to show that the expression of an erwinia herbicola gene in e. coli hb101(pmcg898) resulted in the production of gluconic acid, which, in turn, implied pqq biosynthesis. transposon mutagenesis showed th ...19921325965
in vitro and in vivo antibacterial activities of am-1155, a new 6-fluoro-8-methoxy is a new quinolone with a wide spectrum of antibacterial activity against various bacteria including anaerobes and mycoplasma pneumoniae. am-1155 was 2- to 16-fold more active than ciprofloxacin and ofloxacin against staphylococcus aureus including methicillin-resistant strains, staphylococcus epidermidis, streptococcus pneumoniae, and enterococcus faecalis; its mics for 90% of strains tested were 0.10 to 0.78 micrograms/ml. the activity of am-1155 was comparable to that of ciprofloxacin ...19921332587
epidemiological role of arthropods detectable in health facilities.a total of 161 arthropod specimens were collected from 55 sites in a health care facility during july and september 1990. of the 116 bacterial isolates obtained from their body surfaces 6% were from parasites (mosquitoes), 59% from eusynanthropic arthropods (tenebrionid beetles, flies, german cockroaches, wasps), 16% from hemisynanthropic arthropods (ants, spiders) and 19% from occasionally encountered insects (non-biting midges, moths, beetles). most (88%) of the isolated bacteria were gram-neg ...19921350604
biotransformation of alkyl and aryl carbonates. microbial enriched mixed culture was successfully grown on model alkyl and aryl carbonates. these compounds were degraded by microorganisms at different rates. p-chlorophenyl-2-octyl carbonate and p-nitrobenzyl-2-octyl carbonate were metabolized through the formation of p-chlorophenol and p-nitrobenzyl alcohol respectively. a strain of acinetobacter calcoaceticus isolated from the mixed culture utilized phenyl-2-octyl carbonate by an intracellular hydrolase to phenol and 2-octanol which were further me ...19901366389
natural transformation in acinetobacter calcoaceticus.acinetobacter calcoaceticus is a metabolically versatile microorganism that is naturally competent for dna uptake and incorporation. we have exploited the natural state of competency for studies involving the cloning, organization and expression of genes encoding catabolic enzymes. a. calcoaceticus is able to take up, at high efficiency, genetically engineered dna, incorporate the dna and stably maintain and express the dna. sequence analysis of cloned a. calcoaceticus dna reveals a great deal o ...19901366417
inducible high-level expression of heterologous genes in bacillus megaterium using the regulatory elements of the xylose-utilization operon.we have constructed a shuttle plasmid for bacillus megaterium and escherichia coli that contains the promoter and repressor gene of the b. megaterium-borne operon for xylose utilization. a polylinker downstream of the promoter allows versatile cloning of genes under its transcriptional control. we have placed gdha (encoding glucose dehydrogenase) from b. megaterium, lacz (encoding beta-galactosidase) from e. coli, mro (encoding mutarotase) from acinetobacter calcoaceticus, and human puk (encodin ...19911367576
cloning and nucleotide sequences of the acci restriction-modification genes in acinetobacter calcoaceticus.the genes of the acci restriction-modification system specific for gt(a/c) (g/t)ac were cloned from the chromosomal dna of acinetobacter calcoaceticus, and their nucleotides sequenced. the restriction and modification genes coded for polypeptides with calculated molecular weights of 42,494 and 63,078, respectively. both the enzymes were coded by the same dna strand and the restriction gene was upstream of the methylase gene, separated by 2 bp. the restriction gene was significantly expressed in ...19911368703
ribotyping of the acinetobacter calcoaceticus-acinetobacter baumannii complex.the acinetobacter calcoaceticus-acinetobacter baumannii complex consists of four genotypically distinct but phenotypically very similar bacterial species or dna groups: a. calcoaceticus (dna group 1), a. baumannii (dna group 2), unnamed dna group 3 (p. j. m. bouvet and p. a. d. grimont, int. j. syst. bacteriol. 36:228-240, 1986), and unnamed dna group 13 (i. tjernberg and j. ursing, apmis 97:595-605, 1989). because strains in this complex cause nosocomial outbreaks, it is important to be able to ...19921383266
long-chain alcohol and aldehyde dehydrogenase activities in acinetobacter calcoaceticus strain ho1-n.three alcohol dehydrogenases have been identified in acinetobacter calcoaceticus sp. strain ho1-n: an nad(+)-dependent enzyme and two nadp(+)-dependent enzymes. one of the nadp(+)-dependent alcohol dehydrogenases was partially purified and was specific for long-chain substrates. with tetradecanol as substrate an apparent km value of 5.2 microm was calculated. this enzyme has a pi of 4.5 and a molecular mass of 144 kda. all three alcohol dehydrogenases were constitutively expressed. three aldehyd ...19921402794
analysis of polar lipids from some representative enterobacteria, plesiomonas and acinetobacter by fast atom bombardment-mass atom bombardment-mass spectrometry (fab-ms) was used to analyse lipid extracts of bacteria to assess its usefulness for analysing anionic phospholipids of potential chemotaxonomic value. the following micro-organisms were tested: acinetobacter calcoaceticus, acinetobacter sp., citrobacter freundii, enterobacter cloacae (2 strains), escherichia coli (3 strains), hafnia alvei, klebsiella oxytoca, klebsiella pneumoniae, morganella morganii, plesiomonas shigelloides, proteus mirabilis (3 strain ...19921447059
characterization of a high-affinity iron transport system in acinetobacter baumannii.analysis of a clinical isolate of acinetobacter baumannii showed that this bacterium was able to grow under iron-limiting conditions, using chemically defined growth media containing different iron chelators such as human transferrin, ethylenediaminedi-(o-hydroxyphenyl)acetic acid, nitrilotriacetic acid, and 2,2'-bipyridyl. this iron uptake-proficient phenotype was due to the synthesis and secretion of a catechol-type siderophore compound. utilization bioassays using the salmonella typhimurium i ...19921447137
in vitro and in vivo activities of dq-2556 and its mode of action.dq-2556 is a recently developed cephalosporin with a broad spectrum of antibacterial activity against both gram-positive and gram-negative bacteria. its in vitro activity was roughly comparable to those of cefuzonam and cefpirome and greater than those of ceftazidime, cefepime, and cefclidin against gram-positive bacteria. against gram-negative bacteria, dq-2556 showed almost the same activity as those shown by cefpirome and cefepime. the activity was largely unaffected by culture medium ph or t ...19921482128
[antimicrobial activities of ceftazidime on fresh clinical isolates].antimicrobial activity of ceftazidime (caz) was compared with those of other cephem antibiotics against clinically isolated strains sent to us by medical institutions throughout japan in 1989 and 1991. those strains separated and identified from samples collected from patients with various infections were also examined, and the following results were obtained. 1. the results suggested that, compared with reports of studies conducted with clinical isolates in early 1980's, mic90 of caz in 1991 we ...19921494227
purification of a periplasmic insulin-cleaving proteinase from acinetobacter calcoaceticus.cells of acinetobacter calcoaceticus contain a constitutive periplasmic metalloproteinase showing similar properties as the periplasmic metalloproteinase of escherichia coli. the periplasmic proteinase of a. calcoaceticus was purified, starting from periplasm, by ammonium sulfate precipitation, hydrophobic interaction chromatography and chromatofocusing up to the homogeneity of the enzyme in sds-electrophoresis with a yield of 6.7% and a purification factor of 417. the enzyme has a molecular mas ...19921510571
co-existence of beta-lactamase and penicillin acylase in bacteria; detection and quantitative determination of enzyme activities.twenty-six bacteria were examined for the presence of penicillin acylase and beta-lactamase. a copper reducing assay, which was sensitive in the analytical range 2-20 micrograms/ml, was used for determination of penicilloates and a fluorescamine assay was used to determine 6-aminopenicillanic acid concentrations when both substances were produced by the action of the enzymes on a single substrate. seventeen bacteria contained beta-lactamases, six contained penicillin acylases and four contained ...19921512174
purification and characterization of l-2,4-diaminobutyrate decarboxylase from acinetobacter calcoaceticus.acinetobacter calcoaceticus atcc 23055 produces a large amount of 1,3-diaminopropane under normal growth conditions. the enzyme responsible, l-2,4-diaminobutyrate (daba) decarboxylase (ec 4.1.1.-), was purified to electrophoretic homogeneity from this bacterium. the native enzyme had an m(r) of approximately 108,000, with a pi of 5.0, and was a dimer composed of identical or nearly identical subunits with apparent m(r) 53,000. the enzyme showed hyperbolic kinetics with a km of 1.59 mm for daba a ...19921512577
microbial contamination of enteral feeding solution and its an investigation of microbial contamination of enteral feeding solutions, all 22 residual solutions obtained immediately after administration were contaminated at concentrations of 10(3) to 10(6) viable counts/ml. major contaminants were glucose-nonfermenting gram-negative bacilli such as pseudomonas aeruginosa and acinetobacter calcoaceticus var anitratus. contamination seemed to have been caused by frequent reuse of bag-type containers and the infusion tubes connected to the bags, neither o ...19921524268
purification and characterization of an extracellular beta-lactamase produced by acinetobacter calcoaceticus.a beta-lactamase was purified 430-fold from the culture supernatant of acinetobacter calcoaceticus by ion exchange chromatography on cm-sephadex and affinity chromatography on phenylboronic-acid-agarose. the purified enzyme was homogeneous as judged by sds-page, and was characterized with respect to molecular mass (38 and 41 kda by gel filtration on sephadex g-75 and sds-page, respectively), ph optimum (ph 7.0), temperature optimum (45 degrees c) and isoelectric point (9.3). the beta-lactamase s ...19921527494
plasmid transformation of naturally competent acinetobacter calcoaceticus in non-sterile soil extract and groundwater.the natural transformation of acinetobacter calcoaceticus bd413 (trpe27) was characterized with respect to features that might be important for a possible gene transfer by extracellular dna in natural environments. transformation of competent cells with chromosomal dna (marker trp+) occurred in aqueous solutions of single divalent cations. uptake of dna into the dnase i-resistant state but not the binding of dna to cells was strongly stimulated by divalent cations. an increase of transformation ...19921590708
infective endocarditis of a native valve due to acinetobacter: case report and review.a case of community-acquired infective endocarditis of a native valve that was caused by acinetobacter calcoaceticus subspecies anitratus is presented. the previously reported cases are reviewed, and therapy for this disorder is discussed. the presence of a transient maculopapular rash involving the palms and soles but sparing the face is suggested as a possible early clinical clue to the diagnosis. native valve endocarditis caused by acinetobacter species is an acute, aggressive illness that is ...19921600019
murine antibody responses distinguish rochalimaea henselae from rochalimaea quintana.rochalimaea henselae causes persistent bacteremia, bacillary angiomatosis, and parenchymal bacillary peliosis. detection of a specific antibody response to r. henselae infection may represent an alternative to cultivation as a means of diagnosis. we assessed the specificity of induced murine antibodies for antigens from r. henselae and the closely related species r. quintana. groups of cd-1 mice were inoculated with whole organisms of six strains of r. henselae and two of r. quintana. pre- and p ...19921629326
characterization of transformation-deficient mutants of acinetobacter calcoaceticus.three acinetobacter calcoaceticus transformation-deficient mutants, obtained by insertional mutagenesis with the nptll gene, have been characterized physiologically. one mutant (aac211) was found to be completely transformation deficient, while two others, aac213 and aac214, were severely impaired in transformation efficiency (100-1000 times lower than the wild type). the latter applied to both chromosomal as well as plasmid dna. analysis of the chromosomal dna fragments flanking the nptll gene ...19921630314
outer membranes of gram-negative bacteria are permeable to steroid probes.the permeability of bacterial outer membranes was assayed by coupling the influx of highly hydrophobic probes, 3-oxosteroids, with their subsequent oxidation catalysed by 3-oxosteroid delta 1-dehydrogenase, expressed from a gene cloned from pseudomonas testosteroni. in salmonella typhimurium producing wild-type lipopolysaccharide, the permeability coefficients for uncharged steroids were 0.45 to 1 x 10(-5) cm s-1, and the diffusion appeared to occur mainly through the lipid bilayer domains of th ...19921640833
in vitro and in vivo antibacterial activities of meropenem, a new carbapenem antibiotic.the in vitro and in vivo antibacterial activities of meropenem were compared with those of imipenem, ceftazidime, flomoxef, cefuzonam and cefotiam. meropenem showed a broad antibacterial spectrum against clinical isolates of gram-positive and gram-negative bacteria. against gram-negative bacteria, with the exception of acinetobacter calcoaceticus, meropenem exhibited the most potent activity among the drugs tested. it inhibited all 330 strains of enterobacteriaceae at 0.78 mg/l. meropenem was se ...19921644010
isolation, sequencing, and mutagenesis of the gene encoding cytochrome c553i of paracoccus denitrificans and characterization of the mutant strain.the periplasmically located cytochrome c553i of paracoccus denitrificans was purified from cells grown aerobically on choline as the carbon source. the purified protein was digested with trypsin to obtain several protein fragments. the n-terminal regions of these fragments were sequenced. on the basis of one of these sequences, a mix of 17-mer oligonucleotides was synthesized. by using this mix as a probe, the structural gene encoding cytochrome c553i (cycb) was isolated. the nucleotide sequence ...19911657873
conjugational transfer of recombinant dna in cultures and in soils: host range of pseudomonas putida tol plasmids.recombinant tol plasmid pwwo-eb62 allows pseudomonas putida to grow on p-ethylbenzoate. this plasmid can be transferred to other microorganisms, and its catabolic functions for the metabolism of alkylbenzoates are expressed in a limited number of gram-negative bacteria, including members of pseudomonad rrna group i and escherichia coli. transfer of the recombinant plasmid to erwinia chrysanthemi was observed, but transconjugants failed to grow on alkylbenzoates because they lost catabolic functi ...19911660698
acinetobacter calcoaceticus bacteremia: analysis of 48 cases.the medical records of 48 patients with acinetobacter calcoaceticus bacteremia over a recent two-year period were reviewed retrospectively to determine the epidemiologic and clinical features. there were 34 males and 14 females with a median age of 51 years. forty-six of the cases were hospital-acquired. the characteristics of these patients included residence in the intensive care unit, intubation and ventilatory support, preceding antibiotic therapy and intravascular catheterization. in vitro ...19911685177
survival of bacteria under dry conditions; from a viewpoint of nosocomial infection.the viability of non-sporing bacteria in a dry state was examined. the number of viable cells was determined at various time intervals, after inoculation onto cotton lint and a glass plate. viable cells of mycobacterium bovis were detected more than 2 months after inoculation, and this was the most resistant species to dry conditions among the bacteria tested. in the case of the gram-positive cocci tested and one species of gram-negative rods, acinetobacter calcoaceticus var. anitratus, the viab ...19911685507
[membrane-bound alanine aminopeptidase from acinetobacter calcoaceticus. 4. amino acid chloromethyl ketones as ph-dependent, substrate-derived inhibitors of cysteine protease].the alanine aminopeptidase (aap) from a. calcoaceticus is a metal-ion-dependent cysteine protease bound to the inner membranes of the cells. amino acid chloromethyl ketones are highly specific inhibitors of the enzyme. the aap is inhibited at ph 7.5 (ph-optimum) by mixed-type inhibition. a competitive inhibition type results if the ph value is decreased to 6.2. in contrast, the inhibition of the aap by substrate-derived chloromethyl ketones is of the irreversible type at ph 8.25.19911686704
carbohydrate utilization in streptococcus thermophilus: characterization of the genes for aldose 1-epimerase (mutarotase) and udpglucose 4-epimerase.the complete nucleotide sequences of the genes encoding aldose 1-epimerase (mutarotase) (galm) and udpglucose 4-epimerase (gale) and flanking regions of streptococcus thermophilus have been determined. both genes are located immediately upstream of the s. thermophilus lac operon. to facilitate the isolation of gale, a special polymerase chain reaction-based technique was used to amplify the region upstream of galm prior to cloning. the galm protein was homologous to the mutarotase of acinetobact ...19901694527
[gram-negative flora of horticulture products prevalently to be consumed fresh. ii, acinetobacter calcoaceticus]. 19901711345
outer membrane permeability of acinetobacter calcoaceticus and its implication in antibiotic order to understand high and broad antibiotic resistance of acinetobacter calcoaceticus, the outer membrane permeability was studied. the permeability coefficients of zwitterionic cephalosporins in the intact cell outer membrane were 0.14-1.12 x 10(-4) cm3/min/mg protein. these values were two to seven times lower than the permeability coefficients of the same beta-lactams in the outer membrane of pseudomonas aeruginosa. the diffusion rates of carbapenems and zwitterionic cephalosporins into ...19911722802
genetic analysis of supraoperonic clustering by use of natural transformation in acinetobacter calcoaceticus.dna within escherichia coli colonies carrying cloned acinetobacter calcoaceticus genes transforms mutant a. calocaceticus cells with high efficiency. therefore, e. coli colonies containing such cloned genes can be identified by replica plating onto a lawn of a. calcoaceticus mutant cells. transformation of a. calcoaceticus also facilitates gap repair and thus allows recovery of specified chromosomal segments in recombinant plasmids. these procedures were used to demonstrate the clustering of a. ...19921729209
phosphorylation of acinetobacter isocitrate lyase.during growth on succinate, acinetobacter calcoaceticus contains two forms of the enzyme isocitrate dehydrogenase. addition of acetate to a lag-phase culture grown on succinate causes a dramatic increase in activity of form ii of isocitrate dehydrogenase and in isocitrate lyase. form ii of isocitrate dehydrogenase may be responsible for the partition of isocitrate between the tca cycle and the glyoxylate by-pass. this report describes the phosphorylation of the enzyme isocitrate lyase from a. ca ...19921731794
cis-diol dehydrogenases encoded by the tol pww0 plasmid xyll gene and the acinetobacter calcoaceticus chromosomal bend gene are members of the short-chain alcohol dehydrogenase the aerobic degradation of benzoate by bacteria, benzoate is first dihydroxylated by a ring-hydroxylating dioxygenase to form a cis-diol (1,2-dihydroxycyclohexa-3,4-diene carboxylate) which is subsequently transformed to a catechol by an nad(+)-dependent cis-diol dehydrogenase. the structural gene for this dehydrogenase, encoded on tol plasmid pww0 of pseudomonas putida (xyll) and that encoded on the chromosome of acinetobacter calcoaceticus (bend), were sequenced. they encode polypeptides of ...19921740120
use of a broad-host-range gyra plasmid for genetic characterization of fluoroquinolone-resistant gram-negative bacteria.the gyra genotypes of ciprofloxacin-resistant clinical isolates of escherichia coli (n = 3), klebsiella pneumoniae (n = 4), providencia stuartii (n = 2), pseudomonas aeruginosa (n = 1), and acinetobacter calcoaceticus (n = 1) were analyzed in a dominance test. this test is based on the dominance of a wild-type gyra gene (gyra+) over the quinolone resistance allele (gyra) in a heterodiploid strain. plasmid pbp515, developed to carry the gyra+ gene of e. coli k-12 on a broad-host-range vector deri ...19911759823
[quantitation of acinetobacter calcoaceticus in mixed bacterial cultures by an enzyme immunoassay].an enzyme-linked immunosorbent assay using polyclonal antibodies from rabbits has been developed for quantification of acinetobacter calcoaceticus. bacteria were added to the wells of a microtiter plate coated with anti-acinetobacter immunoglobulin. for detecting bound cells the peroxidase-labelled immunoglobulin fraction was used. over a distinct range there is a linear correlation between bound bacteria and measured absorbance allowing a quantification of bacteria in an order from 10(7) to 10( ...19911793089
release of transforming plasmid and chromosomal dna from two cultured soil bacteria.the release of chromosomal and plasmid dna from acinetobacter calcoaceticus and bacillus subtilis cultivated in minimal medium and broth over a period of 50 h was monitored and related to growth phase, autolysis, dnase production and natural competence. the released dnas were biologically active in natural transformation. in addition, the circular integrity of a released b. subtilis shuttle vector (phv14) was demonstrated by artificial transformation of escherichia coli. in cultures of both stra ...19911793338
[susceptibilities of clinical bacterial isolates to antimicrobial agents, 1989. a study mainly focused on imipenem. the research group for testing imipenem susceptibilities of clinical isolates].we investigated susceptibilities of clinical bacterial isolates to imipenem (ipm) and other antimicrobial agents at hospital laboratories throughout japan from september to december of 1989. the susceptibility testing was carried out according to the 1-dilution or 3-dilution disc technique in which susceptibilities are classified into 4 grades: (+++), (++), (+) and (-). ipm showed markedly high in vitro activities against streptococcus pneumoniae, neisseria gonorrhoeae, moraxella catarrhalis, es ...19911798067
[sensitivity of acinetobacter calcoaceticus-baumanni complex and acinetobacter lwoffi to common antibiotics]. 19911799617
[effects of antibiotics and anti-bacterial components of preparations for local treatment of suppurative wounds on pathogens of odonto- genic infections].the results of identification and sensitivity assay of 156 strains of pathogens causing odontogenic infections are presented. in the sensitivity assay antibacterial drugs were used. 42.3 percent of the strains were obligate anaerobes belonging to bacteroides, fusobacterium, peptococcus, peptostreptococcus, veillonella and actinomyces. significant differences in the microbial sensitivity to the drugs used for general and local therapy were detected. there was observed high sensitivity of the obli ...19911805697
[imipenem-cilastatin cure of meningitis caused by acinetobacter calcoaceticus]. 19911805958
mechanisms of resistance to beta-lactam antibiotics in acinetobacter calcoaceticus.examination of 12 strains of acinetobacter calcoaceticus revealed that the strains expressed different constitutive levels of beta-lactamase. mutants resistant to cefoxitin, cefoperazone or ceftazidime were selected from a strain producing a low level of beta-lactamase. all the mutants showed no change in expression of beta-lactamase, but produced penicillin-binding proteins with altered expression and/or affinity for beta-lactams. in addition, the outer membrane of the mutants showed decreased ...19911816177
[sensitivity of bacteria of the genus acinetobacter to antibiotics and ofloxacin].between 1989-1989 276 strains of acinetobacter genus were isolated which contained: acinetobacter calcoaceticus subsp. anitratus (n = 167), acinetobacter calcoaceticus subsp. iwoffi (n- = 83), acinetobacter haemolyticus (n = 26). their sensitivity to aminoglycoside antibiotics, beta-lactams, tetracyclines, chloramphenicol, colistin, and ofloxacin was tested. more than 90% of strains were sensitive to colistin and ofloxacin. the sensitivity to remaining antibiotics differentiated depending on spe ...19911823372
[acinetobacter in a metropolitan neonatal unit: clinical and microbiological aspects].acinetobacter calcoaceticus var. anitratus (aca) was isolated from two newborn infants and var. iwoffi of the same species from a third patient within a month in the neonatal unit of a general hospital at metropolitan santiago, chile. the first isolate was obtained from a neonate with infection of the skin surrounding a colostomy operation after surgery for tracheo esophageal fistulae, in march 1989. the second case's skin became colonized after he was admitted for surgical repair of severe gast ...19911844163
[intrahospital septicemia due to acinetobacter calcoaceticus var. anitratus in a neonatal intensive care unit].twenty-one cases of sepsis by acinetobacter calcoaceticus biovar anitratus occurred, ten in 1989 and eleven in 1990 (january-april). in this last year, there were nine cases with characteristics of an epidemic outbreak. it was noted that sepsis was predominant in males, babies of less than 2,500 g and less than 37 weeks of gestation. they were hospitalized in our intensive care unit for different problems, but almost all had mechanical ventilation, parenteral nutrition and received antibiotics p ...19911844938
susceptibility of xanthomonas maltophilia and amikacin-resistant gram-negative bacteria to newer antimicrobials.the susceptibility of xanthomonas maltophilia and amikacin-resistant gram-negative bacteria to a variety of newer antimicrobials was determined. sixty-three amikacin-resistant isolates were collected from 61 inpatients at a tertiary-care hospital between 1985 and 1988. the organisms included xanthomonas maltophilia (24 isolates), pseudomonas aeruginosa (16), pseudomonas species (3), serratia marcescens (10), flavobacterium meningosepticum (4), enterobacter species (3), acinetobacter calcoaceticu ...19911860303
nucleotide sequences of the acinetobacter calcoaceticus benabc genes for benzoate 1,2-dioxygenase reveal evolutionary relationships among multicomponent oxygenases.the nucleotide sequences of the acinetobacter calcoaceticus benabc genes encoding a multicomponent oxygenase for the conversion of benzoate to a nonaromatic cis-diol were determined. the enzyme, benzoate 1,2-dioxygenase, is composed of a hydroxylase component, encoded by benab, and an electron transfer component, encoded by benc. comparison of the deduced amino acid sequences of benabc with related sequences, including those for the multicomponent toluate, toluene, benzene, and naphthalene 1,2-d ...19911885518
in vitro and in vivo evaluation of ro 09-1428, a new parenteral cephalosporin with high antipseudomonal 09-1428, a new parenteral cephalosporin with a catechol moiety attached at position 7 of the cephalosporin ring, showed high in vitro activity against escherichia coli, klebsiella pneumoniae, proteus mirabilis, proteus vulgaris, and streptococcus pyogenes, with mics for 90% of strains tested (mic90s) of less than or equal to 0.39 micrograms/ml. morganella morganii, providencia rettgeri, citrobacter freundii, haemophilus influenzae, staphylococcus aureus, and streptococcus pneumoniae were inhi ...19911906261
community acquired pneumonia: aetiology and prognostic index evaluation.a 10 month prospective study of all adults admitted to waikato hospital with community acquired pneumonia was performed to assess aetiology, mortality, hospital stay, and the value of a prognostic index based on that obtained from a british thoracic society study. the 92 patients in the survey had a mean age of 56 (range 13-97) years. a microbiological diagnosis was established in 72%; streptococcus pneumoniae (33%), mycoplasma pneumoniae (18%), and influenza a virus (8%) were the most common mi ...19911907034
[antimicrobial activity of cefpiramide to fresh clinical isolates].in the subjects of 835 strains of 37 clinically isolated microbial strains, which were separated and identified among materials collected from patients with various infections and which were sent from medical therapeutic institutions throughout japan in 1990, for the purpose of examining the antimicrobial activity of cefpiramide (cpm), its minimum inhibitory concentration (mic), together with those of other cephem antibiotics, was determined, and the following conclusions were obtained. 1. micro ...19911920808
imipenem/cilastatin as secondary therapy for bacterial infections.imipenem/cilastatin (ipm/cs) was used to treat 39 documented infections in patients who had failed to respond to other antibiotic regimens. the overall response rating was 76.9%. respiratory infections responded less frequently (efficacy rating, 55.6%) to ipm/cs than abdominal infections, urinary tract infections, or sepsis. methicillin-resistant staphylococcus aureus, xanthomonas maltophilia, and acinetobacter calcoaceticus were less sensitive to ipm/cs therapy than the other bacterial strains ...19911933995
purification and characterization of acinetobacter calcoaceticus isocitrate lyase.acinetobacter calcoaceticus is capable of growing on acetate or compounds that are metabolized to acetate. during adaptation to growth on acetate, a. calcoaceticus b4 exhibits an increase in nadp(+)-isocitrate dehydrogenase and isocitrate lyase activities. in contrast, during adaptation to growth on acetate, escherichia coli exhibits a decrease in nadp(+)-isocitrate dehydrogenase activity that is caused by reversible phosphorylation of specific serine residues on this enzyme. also, in e. coli, i ...19911938889
potential dna slippage structures acquired during evolutionary divergence of acinetobacter calcoaceticus chromosomal benabc and pseudomonas putida tol pww0 plasmid xylxyz, genes encoding benzoate dioxygenases.the xylxyz dna region is carried on the tol pww0 plasmid in pseudomonas putida and encodes a benzoate dioxygenase with broad substrate specificity. the dna sequence of the region is presented and compared with benabc, the chromosomal region encoding the benzoate dioxygenase of acinetobacter calcoaceticus. corresponding genes from the two biological sources share common ancestry: comparison of aligned xylx-bena, xyly-benb, and xylz-benc amino acid sequences revealed respective identities of 58.3, ...19911938949
microbial growth and endotoxin production in the intravenous anesthetic this study, we measured microbial growth and endotoxin production in the intravenous anesthetic propofol using 10 different microbial strains; 6 isolated from outbreak cases and 4 from laboratory stock cultures.19911940276
association of contaminated gloves with transmission of acinetobacter calcoaceticus var. anitratus in an intensive care unit.acinetobacter calcoaceticus var. anitratus is an important nosocomial pathogen that has been associated with environmental reservoirs. an increased isolation rate of a. anitratus in our intensive care units (icus), from 0.03% (two of 7,800) to 0.5% (seven of 1,300) (p less than 0.00003), prompted an investigation.19911951409
[antibacterial activities of ofloxacin against recent isolates from patients with community-acquired infections].in order to survey antibacterial activities of ofloxacin (oflx) against 1,440 bacterial strains isolated from patients with community-acquired infections in 1987 and 1990, minimum inhibitory concentrations (mics) of the drug as well as those of other new quinolones and oral cephems were determined. the following conclusions were reached. 1. comparison of the mic distribution for strains isolated in 1987 with those in 1990 suggested a tendency toward an increase in the frequency of oflx-resistant ...19911960856
a sheep survived for 48 days with the biventricular bypass type total artificial heart.a biventricular bypass type total artificial heart (bvb-tah) utilizing two pusher-plate pumps was developed and implanted in a sheep for 48 days with excellent results. a hall effect sensor was utilized to operate each pump independently with a full stroke at variable rates (vr). with this system, the animal's hemodynamics was kept physiologically, and all metabolic parameters except hemoglobin and hematocrit returned to normal three weeks after implantation. however, signs of infection appeared ...19911962530
in-vitro and in-vivo activities of sulbactam and ytr830h against acinetobacter calcoaceticus.the antibacterial activities of sulbactam and ytr830h, both beta-lactamase inhibitors, were studied against acinetobacter calcoaceticus, in vitro and in vivo. in-vitro susceptibility tests showed both to be very active against 80 clinical isolates of a. calcoaceticus. against an intraperitioneal infection in mice, caused by a. calcoaceticus ac54, the 50% effective doses of sulbactam and ytr830h were 1.62 and 16.7 mg/kg, respectively. against a. calcoaceticus s31, a strain resistant to gentamicin ...19901964157
the survival of acinetobacter calcoaceticus inoculated on fingertips and on formica.when inoculated on the fingers of three volunteers, strains of acinetobacter calcoaceticus var. anitratus survived better than strains of var. lwoffii; 60 min after an inoculum of 10(4) cfu/finger, washings yielded between 2.6 x 10(1) (for a sporadic strain of var. lwoffii) and 7.2 x 10(2) cfu/finger (for an epidemic strain of var. anitratus). all five test strains survived better on formica than on skin, and from an inoculum of 10(4) cfu, between 6.4 x 10(2) and 2.2 x 10(3) cfu/finger were reco ...19901971628
[a membrane-bound alanine aminopeptidase from acinetobacter calcoaceticus. 3. inhibition of the enzyme].the alanine aminopeptidase from acinetobacter calcoaceticus is inhibited by sh-reagents like p-hydroxymercuribenzote, ellman's reagent, n-bromosuccinimide, and metal chelating agents like 1,10-phenanthroline. the aap is competitively inhibited by l-amino acids such as leucine, phenylalanine, and valine having hydrophobic side chains. bacitracin (ki = 2.0.10(-6) mol/l) inhibits aap stronger than puromycin (ki = 8.0.10(-6) mol/l). in contrast, the aeromonas aminopeptidase (ec is stronge ...19901980190
[epidemiologic study of pathogens causing nosocomial infections].nosocomial infection is a global problem. it significantly adds to the expected duration of hospitalization resulting with an increased economic burden and represents a leading cause of death. the characteristics of nosocomial infection vary from country to country and also changes with time. in order to understand the pathogens causing nosocomial infection in the large teaching hospital in taiwan, we collected and analysed the surveillence data of nosocomial infection at the national taiwan uni ...19901982123
comparison of benzyl alcohol dehydrogenases and benzaldehyde dehydrogenases from the benzyl alcohol and mandelate pathways in acinetobacter calcoaceticus and from the tol-plasmid-encoded toluene pathway in pseudomonas putida. n-terminal amino acid sequences, amino acid compositions and immunological cross-reactions.1. n-terminal sequences were determined for benzyl alcohol dehydrogenase, benzaldehyde dehydrogenase i and benzaldehyde dehydrogenase ii from acinetobacter calcoaceticus n.c.i.b. 8250, benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase encoded by the tol plasmid pww53 in pseudomonas putida mt53 and yeast k(+)-activated aldehyde dehydrogenase. comprehensive details of the sequence determinations have been deposited as supplementary publication sup 50161 (5 pages) at the british library d ...19911989592
immune response to acinetobacter calcoaceticus infection in man.after growth in an iron-depleted chemically-defined medium acinetobacter calcoaceticus expressed four high mol. wt outer-membrane proteins (omps) which were repressed under iron supplementation or in a complex laboratory medium. immunoblotting with serum from a septicaemic patient infected with a. calcoaceticus revealed antibody binding to these iron-repressible omps, indicating that they were expressed in vivo, and also to the 42- and 18-kda omps. although the antibody response to the omps did ...19911990144
fatal septicaemia with selenomonas sputigena and acinetobacter calcoaceticus. a case report.a 38-year-old man with a history of alcohol abuse developed rapidly fulminating septicaemia and died. selenomonas sputigena and acinetobacter calcoaceticus were isolated from a blood culture. selenomonas sputigena is a motile anaerobic gram-negative rod rarely associated with systemic disease. difficulties in isolation and taxonomic identification are discussed.19911993118
reliability of phenotypic tests for identification of acinetobacter species.a numerical approach was used for identification of 198 acinetobacter strains assigned to dna groups according to the classification of tjernberg and ursing (i. tjernberg and j. ursing, apmis 97:595-605, 1989). the matrix used was constructed from data published by bouvet and grimont (p.j.m. bouvet and p.a.d. grimont, int. j. syst. bacteriol. 36:228-240, 1986) and bouvet and jeanjean (p.j.m. bouvet and s. jeanjean, res. microbiol. 140:291-299, 1989). the tests chosen were those of the simplified ...19912007635
cellular fatty acid composition of acinetobacter strains.the cellular fatty acids of the different biotypes of acinetobacter calcoaceticus were determined by high resolution gas-liquid chromatography. while all strains exhibited, qualitatively, similar fatty acid compositions, quantitative differences were observed in strains belonging to defined phenotypic subgroups which can be used for differentiation.19912030649
nucleotide sequence analysis reveals linked n-acetyl hydrolase, thioesterase, transport, and regulatory genes encoded by the bialaphos biosynthetic gene cluster of streptomyces hygroscopicus.nucleotide sequence analysis of a 5,000-bp region of the bialaphos antibiotic production (bap) gene cluster defined five open reading frames (orfs) which predicted structural genes in the order bah, orf1, orf2, and orf3 followed by the regulatory gene, brpa (h. anzai, t. murakami, s. imai, a. satoh, k. nagaoka, and c.j. thompson, j. bacteriol. 169:3482-3488, 1987). the four structural genes were translationally coupled and apparently cotranscribed from an undefined promoter(s) under the positive ...19912066341
in vitro activities of cefoperazone and sulbactam singly and in combination against cefoperazone-resistant members of the family enterobacteriaceae and nonfermenters.among 28,000 isolates of the family enterobacteriaceae and nonfermenters isolated at multiple medical centers, 1,084 (4%) were resistant to cefoperazone (mic, greater than or equal to 64 micrograms/ml) and 1,711 (6%) exhibited cefoperazone mics of 2 to 32 micrograms/ml. ninety-six percent of these 2,795 isolates produced beta-lactamase, as determined by the nitrocefin test. sulbactam alone (8 micrograms/ml) was inactive against 99.6% of the isolates other than acinetobacter calcoaceticus and pse ...19902073118
[susceptibilities of clinical bacterial isolates to antimicrobial agents. a study mainly focused on imipenem. research group for testing imipenem susceptibility on clinical isolates].we investigated susceptibilities of clinical bacterial isolates to imipenem (ipm) and other antimicrobial agents at 459 hospital laboratories throughout japan from september to december of 1988. in this study, identification and susceptibility testing were performed at each hospital laboratory and the tests were carried out according to the 1-dilution or 3-dilution disc technique in which susceptibilities are classified into 4 grades: , ++, + and -. ipm had significantly high activity against st ...19902086814
[nosocomial bacteremia caused by acinetobacter].forty episodes of nosocomial acinetobacter calcoaceticus bacteremia produced by the anitratus type over a period of 4 years were analyzed and compared with a control group of 28 patients with bacteremia produced by gram negative bacilli. although most of acinetobacter bacteremia were endemic an outbreak involving 12 cases were observed in an intensive care unit during the study period. thirteen patients presented a transient bacteremia. when the site of origin of the infection could be establish ...19902098118
[clinical importance of bacteremias caused by acinetobacter calcoaceticus].clinical data from patients with acinetobacter calcoaceticus bacteremia observed during a period of 10 years were retrospectively reviewed. these bacteremias represent the 0.66% of the total number of positive blood cultures observed during the same period of time. the type anitratus was the most common (79.4%) although there were no significant differences in epidemiology, sensitivity, or clinical significance between both types. only in 55.8% of the cases bacteremia was considered of clinical ...19902098121
a 28 kda protein of normal mouse serum binds lipopolysaccharides of gram-negative and lipoteichoic acids of gram-positive bacteria.a 28 kda protein from normal mouse serum known to bind to the inner core region of bacterial lipopolysaccharide (lps) was found to bind also to bacterial poly(glycerophosphate) lipoteichoic acid (lta). twenty-nine preparations of lta were isolated from 19 different bacterial species, purified, chemically analysed, and tested for their ability to bind the 28 kda protein in a complement-dependent hemolysis and hemolysis inhibition assay. all but one were active in one or both systems and one half ...19902099385
removal of lead from aqueous solution by acinetobacter calcoaceticus.a bacterial strain tolerant to the presence of 400 ppm lead was isolated from digested sewage sludge. the organism was identified as acinetobacter calcoaceticus var: anitraus (98% confidence). both viable and formalin-inactivated bacterial cells could remove pb from an aqueous solution. the pb-binding ability of inactivated cells was compared with that of a commercial ion-exchange resin. amberlite ir-120. the metal-binding ability of a. calcoaceticus followed the sequence pb greater than or equa ...19902099791
[peritonitis in continuous ambulatory peritoneal dialysis. microbiological and clinical evaluation].in 1976, popovich et al. described a technique of peritoneal dialysis using bottled dialysate. later oreopoulos et al. modified the technique by using plastic bags. but peritonitis still is a major and potentially serious complication of peritoneal dialysis. we have evaluated a) microbiologic diagnostic methods for infectious peritonitis, b) incidence of etiologic agents, and c) the evolution during antimicrobial treatment. eighteen patients with chronic renal failure of diverse causes were foll ...19902101843
[clinical evaluation of therapy for aspiration pneumonia with imipenem/cilastatin sodium].in an open, prospective, multicenter trial the clinical efficacy of imipenem/cilastatin sodium (ipm/cs) for the treatment of 14 cases with aspiration pneumonia was investigated. the mean age was 75.4 years old. diseases of central nervous system were present in 11 cases, cardiovascular diseases, pulmonary diseases and diabetes mellitus in 2 cases each respectively. seven cases were community-acquired and another seven were hospital-acquired. six cases were moderate and 8 cases were severe. causa ...19902112207
the antimicrobial activity of fleroxacin ro 23-6240, a third generation fluoroquinolone derivative, tested in vitro.the broad antimicrobial spectrum of fleroxacin ro 23-6240 was tested on a panel of bacterial and several mycobacterial species. staph. aureus strains, gramnegative bacteria e. coli, kl. pneumoniae, salmonella spp. were found to be rather susceptible to the tested preparation in vitro. the same was true of those species which are known to feature strong natural resistance, e.g. ps. aeruginosa and acinetobacter calcoaceticus. as regards mycobacteria, complete susceptibility was recorded for 10 m. ...19902112571
bacteriostatic and bactericidal actions of boric acid against bacteria and fungi commonly found in urine.boric acid has been used for over 20 years to preserve urine while in transit for bacteriological examination. it has been suggested that it may be toxic for some urinary pathogens. to investigate this several strains of bacteria and fungi commonly found in urine were exposed to different concentrations of boric acid in nutrient broth. viable counts were made at the outset and at intervals for up to 24 hours at room temperature to detect bacteriostatic or bactericidal effects. at concentrations ...19902116453
[spontaneous transformation in mixed cultures of various types of acinetobacter and during joint growth of acinetobacter calcoaceticus with escherichia coli and pseudomonas aeruginosa].the transfer of chromosomal and plasmid genes was studied via spontaneous transformation is mixed cultures of acinetobacter spp. it turned out that any acinetobacter strain, irrespective of its species specificity, serves as chromosomal dna donor in case the mixed culture contains competent cells of the recipient strain. no transfer took place when non-related bacteria were used as donors. we also studied the transfer into ac. calcoaceticus competent strain cells of small non-conjugative plasmid ...19902126520
[non-hospital-acquired pneumonia caused by acinetobacter calcoaceticus]. 19902128612
[evaluation of microbial air contamination in dental areas].the authors carried out a survey in dental wards in order to evaluate the qualitative and quantitative microbial contamination level of the air, which is considered a crucial habitat for the transmission of many infectious diseases. a high microbial counts were found in all of the environments tested; the microorganisms isolated belonged to pathogenous species such as staphylococcus aureus, staphylococcus haemoliticus, pseudomonas aeruginosa, acinetobacter calcoaceticus var. lwoffi. it seems nec ...19902129101
[comparative activity of imipenem, ceftazidime and cefotaxime against acinetobacter calcoaceticus].the authors compared the in vitro activity of imipenem, ceftazidime and cefotaxime against 100 strains of acinetobacter calcoaceticus isolated in 1986 and 1987. the minimal inhibitory and bactericidal concentrations (mics and mbcs) were determined by the agar dilution and broth microdilution methods respectively, with and without 50 per cent of human serum in the medium to evaluate the possible influence of protein binding. imipenem was the most active of the three drugs against acinetobacter, i ...19902139937
characterisation of a siderophore from acinetobacter calcoaceticus.the gram-negative bacterium acinetobacter calcoaceticus was examined for production of siderophores and iron-repressible outer membrane proteins following growth in iron-restricted media. the iron chelator, 2,3-dihydroxybenzoic acid was identified in the culture supernatant by 1h nuclear magnetic resonance (nmr) spectroscopy and mass spectrometry (ms). a group of outer membrane proteins between 80 and 85 kda were induced under iron restriction.19902144495
native valve endocarditis caused by acinetobacter calcoaceticus subspecies lwoffi.a case of native valve endocarditis due to acinetobacter calcoaceticus in a patient with dental caries is presented. the aortic, mitral and tricuspid valves were affected and showed vegetation by echocardiography in the affected valves. in spite of a good response to antibiotic therapy, multiple embolisms resulted in the patient's death. an autopsy confirmed the vegetation, which was calcified and contained no bacteria.19902150206
analysis and nucleotide sequence of an origin of dna replication in acinetobacter calcoaceticus and its use for escherichia coli shuttle plasmids.a shuttle plasmid for acinetobacter calcoaceticus and escherichia coli has been constructed from a cryptic a. calcoaceticus lwoffi plasmid and pbr322. it is transformed to a. calcoaceticus bd413 by natural competency, yielding about 10(6) transformants per microgram of plasmid dna. the apr and tcr genes of pbr322 are functional in a. calcoaceticus. a gene bank was constructed from chromosomal a. calcoaceticus dna and the shuttle plasmid. direct transformation to a. calcoaceticus yielded about 95 ...19902185139
cross resistance to ciprofloxacin and other antimicrobial agents among clinical isolates of acinetobacter calcoaceticus biovar anitratus.using an agar dilution assay, for 66 of 104 (63.5%) clinical isolates of acinetobacter calcoaceticus biovar anitratus, the mic of ciprofloxacin was greater than or equal to 1.0 micrograms/ml. cross resistance was demonstrable to ciprofloxacin and gentamicin (p less than 0.001), amikacin (p less than 0.01), cefotaxime (p less than 0.001), azlocillin (p less than 0.001), ceftazidime (p less than 0.001), trimethoprim-sulfamethoxazole (p less than 0.001), and minocycline (p less than 0.05). the mean ...19902185692
therapeutic effects of cefpirome, a new cephalosporin, on various models of infections in mice and rats.cefpirome (hr 810) is a new cephalosporin with a 2,3-cyclopentenopyridine group in the 3-position side chain. it was compared with other cephem antibiotics in protective and therapeutic effects on various experimental infections, systemic and local, in mice and rats. hr 810 had more potent protective effect than ceftazidime (caz), cefoperazone (cpz), and cefotaxime (ctx) on systemic infections induced by escherichia coli ec-31, staphylococcus aureus smith, and serratia marcescens sm-6 in mice. a ...19902190011
acinetobacter calcoaceticus from blood culture of children. 19902210834
an outbreak of acinetobacter calcoaceticus infection in a neonatal care unit.between january and december 1988, 383 neonates were admitted to our neonatal intensive care unit. 1,991 swabs and blood cultures were tested bacteriologically. among them 90 specimens obtained from 41 patients were positive for acinetobacter calcoaceticus. during this period we discovered and treated three cases with a. calcoaceticus sepsis. three additional cases had blood cultures positive for this bacterium without demonstrating any clinical signs of infection. there is good evidence that co ...19902210855
ciprofloxacin in the treatment of nosocomial multiply resistant acinetobacter calcoaceticus bacteremia.twelve cases of multiply resistant acinetobacter calcoaceticus bacteremia occurred in three intensive care units in three different outbreaks. all patients were mechanically ventilated, on broad spectrum antibiotics and had central lines when bacteremia occurred. the sites of primary infection were: abdominal (n = 3); respiratory (n = 4); central lines (n = 4); cns (n = 1). in eight cases the acinetobacter strains were susceptible to ciprofloxacin only. four other strains were sensitive to amika ...19902210856
parenteral fluoroquinolones in children with life-threatening infections.the new fluoroquinolones have not been tested in children despite their wide spectrum of in vitro activity and efficacy, because of an observed damage to cartilage in young animals. however, in some cases they may be life-saving. we present three pediatric patients with life threatening infections in whom the fluoroquinolones were used when other antibiotics failed: a seven-year-old boy with meningitis due to multiresistant acinetobacter calcoaceticus, a three-year-old boy with job's syndrome wi ...19902210857
mechanism of enhancement of microbial cell hydrophobicity by cationic polymers.polycationic polymers have been noted for their effects in promoting cell adhesion to various surfaces, but previous studies have failed to describe a mechanism dealing with this type of adhesion. in the present study, three polycationic polymers (chitosan, poly-l-lysine, and lysozyme) were tested for their effects on microbial hydrophobicity, as determined by adhesion to hydrocarbon and polystyrene. test strains (escherichia coli, candida albicans, and a nonhydrophobic mutant, mr-481, derived f ...19902211502
molecular cloning, nucleotide sequence, and promoter structure of the acinetobacter calcoaceticus trpfb operon.the trpfb operon from acinetobacter calcoaceticus encoding the phosphoribosyl anthranilate isomerase and the beta-subunit of tryptophan synthase has been cloned by complementation of a trpb mutation in a. calcoaceticus, identified by deletion analysis, and sequenced. it encodes potential polypeptides of 214 amino acids with a calculated molecular weight of 23,008 (trpf) and 403 amino acids with a molecular weight of 44,296 (trpb). the encoded trpb sequence shows striking homologies to those from ...19902211532
selection of acinetobacter calcoaceticus mutants deficient in the p-hydroxybenzoate hydroxylase gene (poba), a member of a supraoperonic cluster.p-hydroxybenzoate hydroxylase, the product of the poba gene, gives rise to protocatechuate, which is metabolized by enzymes encoded by the pca operon in acinetobacter calcoaceticus. mutations in pcad prevented growth of a. calcoaceticus with succinate in the presence of p-hydroxybenzoate. mutants selected on this medium contained the original mutation in pcad and also carried spontaneous mutations in poba. these independently expressed genes were cotransformed with a frequency of 15% and thus ar ...19902211534
recovery of dna from the acinetobacter calcoaceticus chromosome by gap repair.a strain of acinetobacter calcoaceticus that demonstrates unusually high competence for natural transformation by linear dna has proven valuable for analysis of genes and gene clusters associated with aromatic catabolism. the transformation system allowed gap repair to be used to recover mutant chromosomal dna within recombinant plasmids. the sizes of the recovered fragments, 5 and 7 kilobase pairs in length, indicate that gap repair will be a useful procedure for isolation of wild-type and modi ...19902211536
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