purification of a lipase from acinetobacter calcoaceticus aac323-1 by hydrophobic-interaction methods.the performance of hydrophobic-interaction chromatography (hic) for the purification of acinetobacter calcoaceticus aac323-1 lipase was compared with that of various aqueous two-phase systems. while a 42% lipase yield with a purification factor of 140 could be recovered by hic, higher yields were achieved by using aqueous two-phase systems, either those formed by poly(ethylene glycol) and dextran or those based upon the use of a detergent. triton x-114-based aqueous two-phase partition showed th ...19968867899
inhibition studies of s-adenosylhomocysteine hydrolase purified from acinetobacter calcoaceticus ula-501.adenosine analogs previously reported as reversible inhibitors of mammalian s-adenosylhomocysteine hydrolase (sahase) have been found to exert similar effects on acinetobacter calcoaceticus ula-501 enzyme. in addition, two metal coordination compounds, cis-platinum diammine dichloride (cis-ddp) and its trans isomer (trans-ddp), the former well known for its employment in anticancer chemotherapy, were assayed on both bacterial and mammalian sahases. in our conditions, trans-ddp appeared to be the ...19968874802
increased production of recombinant pyrroloquinoline quinone (pqq) glucose dehydrogenase by metabolically engineered escherichia coli strain capable of pqq biosynthesis.we have previously shown that the production of recombinant escherichia coli pqqgdh was greatly improved by using a medium supplemented with the cofactor pqq, which is not synthesized in e. coli. we show here that the increase in the accumulated pqqgdh is due to the increased stability of the holo-enzyme over apo-enzyme, using recombinant acinetobacter calcoaceticus pqqgdh. in order to achieve cost-effective pqqgdh production, we incorporated the genes for pqq biosynthetic pathway from klebsiell ...19968879174
degradation of crude oil by acinetobacter calcoaceticus and alcaligenes odorans.two types of indian crude oil (bombay high and gujarat) were tested for their biodegradability by acinetobacter calcoaceticus and alcaligenes odorans. acinetobacter calcoaceticus s30 and alc. odorans p20 degraded bombay high crude oil by 50% and 45%, while only 29% and 37% of gujarat crude oil (heavy crude oil) was degraded by these isolates, respectively. acinetobacter calcoaceticus and alc. odorans in combination degraded 58% and 40% of bombay high and gujarat crude oils, respectively, which w ...19968896350
multiparametric analysis of waterline contamination in dental units.microbial contamination of dental unit waterlines is thought to be the result of biofilm formation within the small-bore tubing used for these conduits. systematic sampling of 121 dental units located at the dental school of université de montréal showed that none of the waterlines was spared from bacterial contamination. multilevel statistical analyses showed significant differences between samples taken at the beginning of the day and samples taken after a 2-min purge. differences were also fo ...19968899982
the beta-ketoadipate pathway and the biology of self-identity.the beta-ketoadipate pathway is a chromosomally encoded convergent pathway for aromatic compound degradation that is widely distributed in soil bacteria and fungi. one branch converts protocatechuate, derived from phenolic compounds including p-cresol, 4-hydroxybenzoate and numerous lignin monomers, to beta-ketoadipate. the other branch converts catechol, generated from various aromatic hydrocarbons, amino aromatics, and lignin monomers, also to beta-ketoadipate. two additional steps accomplish ...19968905091
antibiotic resistance pattern and r-plasmids of acinetobacter calcoaceticus subsp. anitratus.during a 6 month period from march 1990 to august 1990, a total of 159 strains of acinetobacter calcoaceticus subsp. anitratus were isolated from various samples and studied for antibiotic resistance pattern to 12 drugs by kirby-bauer method. ceftazidime and netilmycin were the most sensitive drugs followed by cefotaxime, norfloxacin and augmentin. all the strains were resistant to chloramphenicol and tetracycline. commonest pattern of resistance was acgkstsu. forty eight isolates were tested fo ...19958919107
[simultaneous isolation of mrsa and pseudomonas aeruginosa using a novel selective and differential pmac agar].pmac agar, a novel, selective and differential medium has been developed and was subjected for evaluation of its selective and differential capability of methicillin resistant staphylococcus aureus (mrsa) and pseudomonas aeruginosa from other bacteria such as bacillus, micrococcus, gram-negative bacteria and drug resistant ones. growth of mrsa and p. aeruginosa on pmac agar was facilitated and their colonies were easily differentiated. colonies of mrsa after 24 approximately 48 h incubation at 3 ...19968921677
system to study horizontal gene exchange among microorganisms without cultivation of recipients.ribosomal rna genes are characterized by highly conserved sequences and are present in multiple copies in most prokaryotic chromosomes. in principle, therefore, they might serve as sites for homologous recombination between unrelated microorganisms. plasmids containing 23s ribosomal gene sequences, from different bacteria, which had been interrupted by insertion of a kanamycin-resistance gene, were used to transform acinetobacter sp. dsm587 (former name: acinetobacter calcoaceticus bd413-ivl10). ...19968930906
the expression of the acinetobacter calcoaceticus reca gene increases in response to dna damage independently of reca and of development of competence for natural transformation.using the lacz operon fusion technique, the transcriptional control of the acinetobacter calcoaceticus reca gene was studied. a low (approximately twofold) inductive capacity was observed for compounds that damage dna and/or inhibit dna replication, e.g. methyl methanesulfonate, mitomycin c, uv light and nalidixic acid. induction of the reca gene by dna damage was independent of functional reca. the presence of the reca promoter region on a multicopy plasmid had the same effect on reca transcrip ...19968936328
phosphate release and uptake by pure cultures of acinetobacter sp.: effect of the volatile fatty acids concentrationphosphorus release and uptake by pure cultures of acinetobacter strains were investigated under anaerobic and aerobic conditions respectively. tests were performed to study the relationship between phosphorus release-storage reaction and behavior of extracellular organic substrates: acetic, propionic, and butyric acids have been used at four concentrations (50, 100, 500, and 1000 mg · l-1) in the anaerobic step of biological phosphorus removal. the results obtained depend on the strain an ...19978939801
influence of relative humidity and suspending menstrua on survival of acinetobacter spp. on dry surfaces.acinetobacter spp. are being reported with increasing frequency as a cause of nosocomial infection and have been isolated from the skin of healthy individuals, patients, hospital staff, dry nonbiotic objects, and different pieces of medical equipment. factors affecting the survival of acinetobacter spp. under conditions closely similar to those found in the hospital environment were investigated in the present study to help us understand the epidemiology of nosocomial acinetobacter infection. ba ...19968940416
production, characterization, and reconstitution of recombinant quinoprotein glucose dehydrogenase (soluble type; ec apoenzyme of acinetobacter calcoaceticus.soluble, periplasmic quinoprotein glucose dehydrogenase of acinetobacter calcoaceticus (sgdh; ec was produced in good yield in the apoenzyme form (without the cofactor pyrroloquinoline quinone, pqq) by an escherichia coli recombinant strain provided with a plasmid containing the gene under control of a lac promoter. structural analysis of the purified apoenzyme revealed that the e. coli strain used produces the correct mature protein. titration of the apoenzyme with pqq in the presenc ...19968951033
novel nuclear magnetic resonance spectroscopy methods demonstrate preferential carbon source utilization by acinetobacter calcoaceticus.novel nuclear magnetic resonance spectroscopy techniques, designated metabolic observation, were used to study aromatic compound degradation by the soil bacterium acinetobacter calcoaceticus. bacteria which had been rendered spectroscopically invisible by growth with deuterated (2h) medium were used to inoculate cultures in which natural-abundance 1h hydrogen isotopes were provided solely by aromatic carbon sources in an otherwise 2h medium. samples taken during the incubation of these cultures ...19968955304
[microbiology of femoral head grafts in bone banks].the aim of the study was to describe the bacteriology of bone allografts, which were harvested for the bone bank at hvidovr hospital, and to evaluate any infections in the recipients, which may have been caused by microbiological contamination of the transplanted bone allografts. it was carried out as a retrospective examination of bone bank records and patient records allowing at least 12 months for possible manifestation of bacterial infection by the bone allograft. during donation of bone, bo ...19968966808
identification and characterization of a pantoea citrea gene encoding glucose dehydrogenase that is essential for causing pink disease of pineapple.pantoea citrea, a member of the family enterobacteriaceae, causes pink disease of pineapple, whose symptom is characterized by the formation of pink to brown discolorations of the infected portions of the pineapple fruit cylinder upon canning. molecular genetic approaches were applied to elucidate the mechanism responsible for this fruit discoloration. a p. citrea mutant strain, cmc6, defective in its ability to cause pink disease and fruit discoloration, was generated by nitrosoguanidine mutage ...19978979341
[microbial associations in trichomonas urethritis].the results on isolation of associated microflora from 190 patients suffering from trichomonas urethritis are given. microorganisms belonged to the species: mycoplasma hominis. ureaplasma urealyticum. streptococcus pyogenes. escherichia coli. klebsiella pneumoniae. proteus mirabilis. moraxella lacunata. acinetobacter calcoaceticus and candida. staphylococcus cultures which were isolated from 100% patients belonged to 8 species: staphylococcus aureus, s. intermedius, s. haemolyticus, s. epidermid ...19968983524
microbiology of otitis externa.microbiologic and clinical data from 26 patients with otitis externa were prospectively evaluated. specimens were processed for aerobic and anaerobic bacteria. bacterial growth was noted in 23 specimens. a total of 33 aerobic and 2 anaerobic bacteria were recovered. aerobic bacteria only were isolated in 21 (91%) patients, anaerobic bacteria only in 1 (4%), and mixed aerobic and anaerobic bacteria in 1 (4%). the most common isolates were pseudomonas aeruginosa (14 instances), staphylococcus aure ...19979018252
expression, inducer spectrum, domain structure, and function of mopr, the regulator of phenol degradation in acinetobacter calcoaceticus ncib8250.degradation of phenol by acinetobacter calcoaceticus ncib8250 involves (sigma54-dependent expression of a multicomponent phenol hydroxylase and catechol 1,2-dioxygenase encoded by the mop operon. complementation of a new mutant deficient in phenol utilization yielded the regulatory locus mopr. it is located in divergent orientation next to the mop operon. mopr is constitutively expressed at a low level from a sigma70-type promoter and belongs to the ntrc family of regulators. the amino acid sequ ...19979023219
structural and serological characterisation of the o-specific polysaccharide from lipopolysaccharide of acinetobacter calcoaceticus strain 7 (dna group 1).s-form lipopolysaccharide was isolated by phenol/water extraction from a strain of acinetobacter calcoaceticus (dna group 1 ). the structure of the o-antigenic polysaccharide was determined by compositional analysis and nmr spectroscopy of the de-o-acylated lipopolysaccharide. the isolated polysaccharide obtained after hydrolysis of lipopolysaccharide in 0.01 m trifluoroacetic acid has the following structure: [structure in text] in which pyr is pyruvate. the o-acetyl substitution of d-gal was n ...19979030736
[bactericide activity of sulbactam before bacteria belonging to the acinetobacter calcoaceticus-acinetobacter baumannii complex].to evaluate the bactericidal activity of colistin, imipenem and sulbactam against 24 acinetobacter calcoaceticus-acinetobacter baumannii complex isolations.19969035707
[reactive arthritis: terminology, etiology and pathogenesis].different serovars of y. enterocolitica, y. pseudotuberculosis, acinetobacter calcoaceticus, and pseudomonas pauimobilis were isolated from the synovial fluid of 23 out of 34 patients with yersinia-triggered arthritis by a new bacteriological method based on the selection of the optimal conditions for microorganism culturing; in some cases the strains were isolated repeatedly. the authors discuss the necessity of correcting the previous notions on the aseptic nature of reactive arthritis.19969036205
sequence analysis of pqq genes required for biosynthesis of pyrroloquinoline quinone in methylobacterium extorquens am1 and the purification of a biosynthetic intermediate.methylobacterium extorquens am1 produces pyrroloquinoline quinone (pqq), the prosthetic group of methanol dehydrogenase. two genes clusters have been shown to be required for pqq biosynthesis in this micro-organism and complementation analysis has identified seven pqq genes, pqqdgcba and pqqef. the dna sequence of pqqdgc' was reported previously. this paper reports the sequence of the genomic region corresponding to pqqc'ba. for consistency, the nomenclature of pqq genes in klebsiella pneumoniae ...19979043136
sigma54, a vital protein for myxococcus xanthus.the rpon gene encoding the transcription factor sigma54 in myxococcus xanthus has been cloned using a heterologous rpon probe. the sequence of the cross-hybridizing dna confirmed the existence of an orf 1518 bp long that encodes a well conserved member of the sigma54 family of sigma factors. low- as well as high-stringency hybridizations detected only a single rpon gene in the m. xanthus chromosome. in other bacteria, sigma54 is an alternative sigma, and null mutants are viable. however, all att ...19979050890
an apparent outbreak of infection with acinetobacter calcoaceticus reconsidered after investigation by pyrolysis mass a previously reported apparent outbreak of infection due to acinetobacter calcoaceticus on a regional burns unit in which both clinical and environmental isolates were available for study, investigations of the organisms by electrophoretic typing of surface proteins, plasmid profiling and antibiograms were inconclusive and unable to identify a single epidemic strain of the organism. the same collection of isolates has been analysed for inter-strain comparison by pyrolysis mass spectrometry (p ...19979060155
oral treatment of staphylococcus spp. infected orthopaedic implants with fusidic acid or ofloxacin in combination with rifampicin.oral therapy of staphylococcal infection of orthopaedic implants with 900 mg/day rifampicin combined with either 1.5 g/day fusidic acid for 5 days followed by 1 g/day thereafter, or 600 mg/day ofloxacin was compared. patients with an infected hip were treated for 6 months, with removal of any unstable prosthesis after 5 months' treatment and those with an infected knee prosthesis were treated for 9 months, with removal of the prosthesis after 6 months of treatment. patients with infections of ot ...19979069545
nucleotide sequence of a putative periplasmic mn superoxide dismutase from acinetobacter calcoaceticus adp1.we determined 5.8 kilobases of nucleotide sequence upstream of the rubredoxin encoding ruba gene of acinetobacter calcoaceticus (ac) adp1. sequence analysis revealed four open reading frames named cysd', cobq, soda and lyss, coding for proteins with high similarity to known sulfate adenylate transferases (partial), cobyric acid synthases, superoxide dismutases (sod) and lysyl trna synthetases, respectively. out of a large number of bacterial sod sequences soda of ac adp1 is the first member of t ...19979074511
activities of beta-lactams against acinetobacter genospecies as determined by agar dilution and e-test mic methods.the agar dilution mic method was used to test activities of ticarcillin, ticarcillin-clavulanate, amoxicillin, amoxicillin-clavulanate, ampicillin, ampicillin-sulbactam, piperacillin, piperacillin-tazobactam, inhibitors alone, ceftazidime, and imipenem against 237 acinetobacter genospecies. a total of 93.2% of strains were beta-lactamase positive by the chromogenic cephalosporin method. overall, ampicillin-sulbactam was the most active combination against all strains (mic at which 50% of the iso ...19979087486
incorporation of 2-hydroxyl fatty acids by acinetobacter calcoaceticus rag-1 to tailor emulsan structure.acinetobacter calcoaceticus rag-1 was cultured on different chain length saturated 2-hydroxyl fatty acid (2-hofa) carbon sources as follows: c12:0 (2-oh), c14:0 (2-oh), c16:0 (2-oh) and c18:0 (2-oh). these 2-hofas were used as either sole carbon sources or cosubstrates with c14:0 (total 1% w/v) to form new emulsans (ems) having controlled side chain fa structure and, therefore, unique emulsifier characteristics. em yields and cell dry weights ranged from 0.6 to 1.8 g/l and 0.9 to 3.9 g/l, respec ...19979110181
bioengineering of emulsifier structure: emulsan analogs.strategies were investigated to modulate the side chain structure of emulsans formed by acinetobacter calcoaceticus rag-1. analysis of emulsan fatty acid side chain groups by gas chromatography--mass spectrometry (gc-ms) revealed that by provoking the exogenous n-alkanoic fatty acids 15:0, 16:0, and 17:0, emulsan analogs were formed with 53, 46, and 44 mol%, respectively, of fatty acid substituents with chain lengths equal to that of the carbon source. in contrast, the increase in emulsan fatty ...19979115094
sequence and functional analysis of an escherichia coli dna fragment able to complement pqqe and pqqf mutants from methylobacterium organophilum.a 7361 kb fragment of e coli chromosomal dna able to complement pqqe and pqqf mutants of methylobacterium organophilum has been sequenced. five open reading frames (orf) have been identified. four orfs (102, 103, 106 and 107), belong to a single transcription unit. they are separated by a transcription termination site from a fifth orf (orf109). polypeptides of 28, 85 and 82 kda encoded by orfs 102, 103 and 106 respectively were visualised in maxi-cell experiments. both orf106 and orf107 are req ...19969116051
isolation of mutants of acinetobacter calcoaceticus deficient in wax ester synthesis and complementation of one mutation with a gene encoding a fatty acyl coenzyme a reductase.acinetobacter calcoaceticus bd413 accumulates wax esters and triacylglycerol under conditions of mineral nutrient limitation. nitrosoguanidine-induced mutants of strain bd413 were isolated that failed to accumulate wax esters under nitrogen-limited growth conditions. one of the mutants, wow15 (without wax), accumulated wax when grown in the presence of cis-11-hexadecenal and hexadecanol but not hexadecane or hexadecanoic acid. this suggested that the mutation may have inactivated a gene encoding ...19979139916
natural transformation and availability of transforming dna to acinetobacter calcoaceticus in soil microcosms.a small microcosm, based on optimized in vitro transformation conditions, was used to study the ecological factors affecting the transformation of acinetobacter calcoaceticus bd413 in soil. the transforming dna used was a. calcoaceticus homologous chromosomal dna with an inserted gene cassette containing a kanamycin resistance gene, nptii. the effects of soil type (silt loam or loamy sand), bacterial cell density, time of residence of a. calcoaceticus or of dna in soil before transformation, tra ...19979143126
the toxicity of substituted phenolic compounds to a detoxifying and an acetic acid the detoxifying bacterium acinetobacter calcoaceticus 69-v and in the acetic acid bacterium acetobacter methanolicus mb 58, glucose and xylose are oxidized, respectively, via pqq-dependent membrane-bound dehydrogenases, which are linked to the respiratory chain in a manner enabling energy conservation via electron transport phosphorylation (etp) in the cytoplasmic membrane. neither the glucose and gluconic acid nor the xylose and xylonic acid are metabolized. therefore, measurements of sugar ...19979143455
antibacterial activity of bms-180680, a new catechol-containing monobactam.the in vitro activities of a new catechol-containing monobactam, bms-180680 (sq 84,100), were compared to those of aztreonam, ceftazidime, imipenem, piperacillin-tazobactam, ciprofloxacin, amikacin, and trimethoprim-sulfamethoxazole. bms-180680 was often the most active compound against many species of the family enterobacteriaceae, with mics at which 90% of the isolates were inhibited (mic90s) of < or = 0.5 microg/ml for escherichia coli, klebsiella spp., citrobacter diversus, enterobacter aero ...19979145861
the species composition of oligotrophic bacterial communities of lake balaton--a numerical analysis.from among the 565 aerobic and facultatively anaerobic, oligotrophic bacterial isolated obtained from the open water region of the balatonfüred-bay, 58 representative strains were selected for detailed taxonomic-physiological studies and numerical analyses as well as simultaneous comparisons with authentic bacterial strains isolated earlier by langó (1987) from different water habitat of the lake balaton. on the basis of 186 ceded differential diagnostic characteristics involved in these analyse ...19969147724
[exposure to organic dust and microorganisms as a factor affecting respiratory function of workers of purebred horse farms].in two farms of purebred horses, microbiological studies of the air and medical examination of the workers were performed. the concentration of microorganisms in the air were within the range 29.2-336.0 cfu x 10(3)/m3. the respirable fraction in most cases was between 30-60% of the total count. the levels of dust and endotoxin were low except for one sampling point where the concentration of endotoxin was as high as 3.44 g/m3. as many as 16 workers out of the total of 31 examined reported occurr ...19969190233
antibacterial activity of trovafloxacin against nosocomial gram-positive and gram-negative isolates.a total of 1132 clinical isolates from 952 patients with nosocomial infections were tested against the fluoroquinolone trovafloxacin by the agar dilution method. they comprised 285 staphylococci, 111 streptococci, 94 enterococci and 470 isolates of enterobacteriaceae, 92 pseudomonas aeruginosa, 27 stenotrophomonas maltophilia, 28 haemophilus influenzae and 25 acinetobacter calcoaceticus. the in-vitro activity of trovafloxacin was compared with that of ciprofloxacin, norfloxacin, beta-lactam and ...19979222067
uptake and processing of dna by acinetobacter calcoaceticus--a natural transformation, dna in the form of macromolecular fragments can be translocated across the cell envelope of prokaryotic microorganisms. during the past two decades, several, largely mutually contradictory, hypotheses have been forwarded to explain the molecular mechanism and bioenergetics of this translocation process. other biomacromolecules are translocated across the bacterial cell envelope as well, such as polysaccharides and proteins, the latter for instance in the process of the ...19979224889
identification and characterization of xcpr encoding a subunit of the general secretory pathway necessary for dodecane degradation in acinetobacter calcoaceticus adp1.a mutant of acinetobacter calcoaceticus adp1 unable to grow on alkanes was complemented for growth on hexadecane with a dna fragment encoding a protein with homology to xcpr, a subunit of the general secretion pathway for exoproteins in pseudomonas aeruginosa. insertional inactivation of xcpr in a. calcoaceticus adp1 by transcriptional fusion to lacz abolishes secretion of lipase and esterase and leads to lack of growth on dodecane and slower growth on hexadecane. we, therefore, propose the part ...19979226277
phylogenetic relationship of the twenty-one dna groups of the genus acinetobacter as revealed by 16s ribosomal dna sequence analysis.the inter- and intrageneric relationships of members of the genus acinetobacter were investigated by performing a comparative sequence analysis of pcr-amplified 16s ribosomal dnas (rdnas) from 21 strains representing all of the dna groups that have been described. phylogenetic treeing confirmed that acinetobacter spp. form a coherent cluster within the gamma subdivision of the class proteobacteria that includes strains with overall levels of 16s rdna sequence similarity of more than 94%. the ana ...19979226915
interactions of an antimicrobial peptide, magainin 2, with outer and inner membranes of gram-negative bacteria.magainin peptides, isolated from xenopus skin, have broad spectra of antimicrobial activity and low toxicities to normal eukaryotic cells, thus being good candidates for therapeutic agents. the mechanism of action is considered to be the permeabilization of bacterial membranes. a number of studies using lipid vesicles have elucidated its molecular detail. however, their interactions with bacteria are not yet well understood. in this paper, we synthesized several magainin analogs with different c ...19979247173
chemicals and heat generate different protein patterns in acinetobacter calcoaceticus.the effect of exposing acinetobacter calcoaceticus 69-v to dnp-stress and heat shock was examined by two-dimensional gel electrophoresis of proteins, which were detected either by autoradiography or by silver staining. both dnp stress and heat shock led to altered patterns of protein synthesis or concentration. about 10% of the proteins which were synthesized newly or at an increased rate and about 25% of those which were found newly or with an increased concentration after dnp treatment were id ...19979265739
ca2+ and its substitutes have two different binding sites and roles in soluble, quinoprotein (pyrroloquinoline-quinone-containing) glucose investigate the mode of binding and the role of ca2+ in soluble, pyrroloquinoline-quinone (pqq)-containing glucose dehydrogenase of the bacterium acinetobacter calcoaceticus (sgdh), the following enzyme species were prepared and their interconversions studied: monomeric apoenzyme (m); monomer with one firmly bound ca2+ ion (m*); dimer consisting of 2 m* (d); dimer consisting of 2 m and 2 pqq (holo-y); dimer consisting of d with 2 pqq (holo-x); fully reconstituted enzyme consisting of holo-x w ...19979266710
muck, a gene in acinetobacter calcoaceticus adp1 (bd413), encodes the ability to grow on exogenous cis,cis-muconate as the sole carbon source.benzyl alcohol, benzaldehyde, benzoate, and anthranilate are metabolized via catechol, cis,cis-muconate, and the beta-ketoadipate pathway in acinetobacter calcoaceticus adp1 (bd413). mutant strain isa25 with a deletion spanning catbcijf and unable to metabolize muconate further will not grow in the presence of an aromatic precursor of muconate. growth on fumarate as the sole carbon source with added benzyl alcohol or benzaldehyde selected spontaneous mutants of isa25. after repair of the cat del ...19979294455
discrimination of acinetobacter genomic species by aflp fingerprinting.aflp is a novel genomic fingerprinting method based on the selective pcr amplification of restriction fragments. the usability of this method for the differentiation of genomic species in the genus acinetobacter was investigated. a total of 151 classified strains (representing 18 genomic species, including type, reference, and field strains) and 8 unclassified strains were analyzed. by using a single set of restriction enzymes (hindiii and taqi) and one particular set of selective pcr primers, a ...19979336926
identification by site-directed mutagenesis of three essential histidine residues in membrane dipeptidase, a novel mammalian zinc peptidase.membrane dipeptidase (ec is a plasma membrane zinc peptidase that is involved in the renal metabolism of glutathione and its conjugates, such as leukotriene d4. the enzyme lacks the classical signatures of other zinc-dependent hydrolases and shows no homology with any other mammalian protein. we have used site-directed mutagenesis to explore the roles of five histidine residues in pig membrane dipeptidase that are conserved among mammalian species. when expressed in cos-1 cells, the m ...19979337849
use of different pcr-based dna fingerprinting techniques and pulsed-field gel electrophoresis to investigate the epidemiology of acinetobacter calcoaceticus-acinetobacter baumannii complex.acinetobacter calcoaceticus-acinetobacter baumannii complex is an important nosocomial pathogen for which optimal typing methods in epidemiologic investigations have not been defined. we compared dna macrorestriction analysis by pulsed-field gel electrophoresis (pfge) with different pcr-based dna fingerprinting techniques, including enterobacterial repetitive intergenic consensus (eric) polymerase chain reaction (pcr), repetitive extragenic palindromic (rep) pcr, arbitrary-primed pcr with primer ...19979350411
bovine spongiform encephalopathy: is it an autoimmune disease due to bacteria showing molecular mimicry with brain antigens?bovine spongiform encephalopathy (bse) could be an autoimmune disease produced following exposure of cattle to feedstuffs containing bacteria showing molecular mimicry between bacterial components and bovine tissue. analysis of molecular sequence databases (genbank and swissprot) shows that three bacteria (acinetobacter calcoaceticus,ruminococcus albus, and agrobacter tumefaciens) share sequences with the encephalitogenic peptide of bovine myelin, while three molecules in escherichia coli show m ...19979370514
cloning and sequencing of genes encoding malonate decarboxylase in acinetobacter calcoaceticus.malonate decarboxylase from acinetobacter calcoaceticus was isolated and characterized (kim, y.s., byun, h.s., j. biol. chem. 269 (1994) 29636-29641), and its subunits were reanalyzed recently to be alpha, beta, gamma, and delta. the genes for the subunits, mdca (548 a.a.), b (295 a.a.), c (238 a.a.), and d (102 a.a.), of the enzyme have been cloned by using oligonucleotide primers deduced from amino acid sequences of peptides isolated from the purified enzyme, and sequenced to be clustered in a ...19979375791
antibiotic resistance among gram-negative nosocomial pathogens in the intensive care unit: results of 6-year body-site monitoring.results of 6-year body-site monitoring in an intensive care unit (icu) are presented and antimicrobial resistance of gram-negative isolates analyzed. the study included 622 patients. six hundred thirty-five bacterial isolates-causes of nosocomial sepsis, pneumonia, and urinary tract infections (utis)-were tested during the study. gram-negative bacteria were the predominant isolates, causing 65% of cases of sepsis, 78.7% of pneumonias, and 70.2% of utis. gram-negative isolates (454) were highly r ...19979377613
multicenter study using standardized protocols and reagents for evaluation of reproducibility of pcr-based fingerprinting of acinetobacter laboratories in six european countries examined 40 isolates belonging to the acinetobacter calcoaceticus-acinetobacter baumannii complex to investigate whether standardized protocols and quality-controlled reagents could produce reliable, discriminatory, and reproducible pcr-based fingerprinting results. four pcr protocols with different primers (primers daf4, eric-2, m13, and rep1 + rep2) were used. the epidemiological conclusions reached by the participating laboratories were substantial ...19979399496
morpholine degradation pathway of mycobacterium aurum mo1: direct evidence of intermediates by in situ 1h nuclear magnetic resonance.resting mycobacterium aurum mo1 cells were incubated with morpholine, a waste from the chemical industry. the kinetics of biodegradation was monitored by using in situ nuclear magnetic resonance (nmr). the incubation medium was directly analyzed by 1h nmr. this technique allowed the unambiguous identification of two intermediates of the metabolic pathway involved in the biodegradation process, glycolate and 2-(2-aminoethoxy)acetate. the latter compound, which was not commercially available, was ...19989435073
[accbsi - a novel restriction endonuclease from acinetobacter calcoaceticus bs].the recognition site of a new restriction endonuclease from acinetobacter calcoaceticus bs was determined. this is a nonpalindromic sequence. accbsi restrictase cleaves dna chains in the middle of the recognition sequence; therefore, ligation of its digestion fragments restored accbsi recognition sites and generated palindromic sequences recognized by saci and sacii restrictases.19979441298
characterization of a gene cluster from ralstonia eutropha jmp134 encoding metabolism of 4-methylmuconolactone.a 2,585 bp chromosomal dna segment of ralstonia eutropha jmp134 (formerly: alcaligenes eutrophus jmp134) which contains a gene cluster encoding part of the modified ortho-cleavage pathway encodes a putative transport protein for 4-methylmuconolactone, a novel 4-methylmuconolactone methylisomerase and methylmuconolactone isomerase. the putative 4-methylmuconolactone transporter, a protein with a calculated molecular mass of 45.8 kda, exhibits sequence homology to other members of the major superf ...19989461415
a cold-adapted lipase of an alaskan psychrotroph, pseudomonas sp. strain b11-1: gene cloning and enzyme purification and characterization.a psychrotrophic bacterium producing a cold-adapted lipase upon growth at low temperatures was isolated from alaskan soil and identified as a pseudomonas strain. the lipase gene (lipp) was cloned from the strain and sequenced. the amino acid sequence deduced from the nucleotide sequence of the gene (924 bp) corresponded to a protein of 308 amino acid residues with a molecular weight of 33,714. lipp also has consensus motifs conserved in other cold-adapted lipases, i.e., lipase 2 from antarctic m ...19989464382
prevalence of broad-host-range lytic bacteriophages of sphaerotilus natans, escherichia coli, and pseudomonas aeruginosa.two bacteriophage collections were examined with regard to their ability to form plaques on multiple bacterial host species. nine of 10 phages studied were found to be broad-host-range bacteriophages. these phages fell into two groups. group 1, the sn series, was isolated from sewage treatment plant samples with sphaerotilus natans atcc 13338 as a host. the dnas of these bacteriophages contained modified bases and were insensitive to cleavage by type i and ii restriction endonucleases. the effic ...19989464396
engineering of quasi-natural pseudomonas putida strains for toluene metabolism through an ortho-cleavage degradation construct a bacterial catalyst for bioconversion of toluene and several alkyl and chloro- and nitro-substituted derivatives into the corresponding benzoates, the upper tol operon of plasmid pww0 of pseudomonas putida was fully reassembled as a single gene cassette along with its cognate regulatory gene, xylr. the corresponding dna segment was then targeted to the chromosome of a p. putida strain by using a genetic technique that allows deletion of all recombinant tags inherited from previous ...19989464417
expression of genes from rahnella aquatilis that are necessary for mineral phosphate solubilization in escherichia coli.rahnella aquatilis is a gram-negative bacterium that can fix atmospheric nitrogen and also has the ability to solubilize mineral phosphate. we have cloned the genes that confer the mineral phosphate solubilizing (mps) trait from this organism by mobilizing a cosmid library of r. aquatilis into escherichia coli hb101. a 7.0-kb ecori fragment from a cosmid, when transferred into e. coli strains hb101 and dh5 alpha, conferred the ability to solubilize hydroxyapatite and the production of gluconic a ...19989485602
molecular characterization of benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase ii of acinetobacter calcoaceticus.the nucleotide sequences of xylb and xylc from acinetobacter calcoaceticus, the genes encoding benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase ii, were determined. the complete nucleotide sequence indicates that these two genes form part of an operon and this was supported by heterologous expression and physiological studies. benzaldehyde dehydrogenase ii is a 51654 da protein with 484 amino acids per subunit and it is typical of other prokaryotic and eukaryotic aldehyde dehydrogenas ...19989494109
genetic and functional analysis of the styrene catabolic cluster of pseudomonas sp. strain y2.the chromosomal region of pseudomonas sp. strain y2 involved in the conversion of styrene to phenylacetate (upper catabolic pathway) has been cloned and sequenced. four catabolic genes, styabcd, and two regulatory genes, stysr, were identified. this gene cluster when transferred to escherichia coli w confers to this phenylacetate-degrading host the ability to grow on styrene as the sole carbon and energy source. genes styabcd are homologous to those encoding the styrene upper catabolic pathway i ...19989495743
characterization of a protocatechuate catabolic gene cluster from rhodococcus opacus 1cp: evidence for a merged enzyme with 4-carboxymuconolactone-decarboxylating and 3-oxoadipate enol-lactone-hydrolyzing activity.the catechol and protocatechuate branches of the 3-oxoadipate pathway, which are important for the bacterial degradation of aromatic compounds, converge at the common intermediate 3-oxoadipate enol-lactone. a 3-oxoadipate enol-lactone-hydrolyzing enzyme, purified from benzoate-grown cells of rhodococcus opacus (erythropolis) 1cp, was found to have a larger molecular mass under denaturing conditions than the corresponding enzymes previously purified from gamma-proteobacteria. sequencing of the n ...19989495744
evolutionary relationship between chlorocatechol catabolic enzymes from rhodococcus opacus 1cp and their counterparts in proteobacteria: sequence divergence and functional convergence.biochemical investigations of the muconate and chloromuconate cycloisomerases from the chlorophenol-utilizing strain rhodococcus opacus (erythropolis) 1cp had previously indicated that the chlorocatechol catabolic pathway of this strain may have developed independently from the corresponding pathways of proteobacteria. to test this hypothesis, we cloned the chlorocatechol catabolic gene cluster of strain 1cp by using pcr with primers derived from sequences of n termini and peptides of purified c ...19989495745
enzyme specificity of 2-nitrotoluene 2,3-dioxygenase from pseudomonas sp. strain js42 is determined by the c-terminal region of the alpha subunit of the oxygenase component.biotransformations with recombinant escherichia coli expressing the genes encoding 2-nitrotoluene 2,3-dioxygenase (2ntdo) from pseudomonas sp. strain js42 demonstrated that 2ntdo catalyzes the dihydroxylation and/or monohydroxylation of a wide range of aromatic compounds. extremely high nucleotide and deduced amino acid sequence identity exists between the components from 2ntdo and the corresponding components from 2,4-dinitrotoluene dioxygenase (2,4-dntdo) from burkholderia sp. strain dnt (form ...19989495758
isolation, characterization, and transfer of cryptic gene-mobilizing plasmids in the wheat rhizosphere.a set of self-transmissible plasmids with incq plasmid-mobilizing capacity was isolated by triparental exogenous isolation from the wheat rhizosphere with an escherichia coli incq plasmid host and a ralstonia eutropha recipient. three plasmids of 38 to 45 kb, denoted pipo1, pipo2, and pipo3, were selected for further study. no selectable traits (antibiotic or heavy-metal resistance) were identified in these plasmids. the plasmids were characterized by replicon typing via pcr and hybridization wi ...19989501428
transcription of ppk from acinetobacter sp. strain adp1, encoding a putative polyphosphate kinase, is induced by phosphate starvation.polyphosphate kinase (ppk) catalyzes the formation of polyphosphate from atp. we cloned the ppk gene (2,073 bp) from acinetobacter sp. strain adp1; this gene encodes a putative polypeptide of 78.6 kda with extensive homology to polyphosphate kinase from escherichia coli and other bacteria. chromosomal disruption of ppk by inserting a transcriptionally fused lacz does not affect growth under conditions of phosphate limitation or excess. beta-galactosidase activity expressed from the single-copy p ...19989501429
bacterial community dynamics during start-up of a trickle-bed bioreactor degrading aromatic compounds.this study was performed with a laboratory-scale fixed-bed bioreactor degrading a mixture of aromatic compounds (solvesso100). the starter culture for the bioreactor was prepared in a fermentor with a wastewater sample of a care painting facility as the inoculum and solvesso100 as the sole carbon source. the bacterial community dynamics in the fermentor and the bioreactor were examined by a conventional isolation procedure and in situ hybridization with fluorescently labeled rrna-targeted oligon ...19989501433
species-specific and ubiquitous-dna-based assays for rapid identification of staphylococcus aureus.staphylococcus aureus is the cause of serious infections in humans, including endocarditis, deep-seated abscesses, and bacteremia, which lead to toxic and septic shock syndromes. rapid and direct identification of this bacterium specifically and ubiquitously directly from clinical specimens would be useful in improving the diagnosis of s. aureus infections in the clinical microbiology laboratory. a wide variety of kits based on biochemical characteristics efficiently identify s. aureus, but the ...19989508283
[bacterial strains isolated from neutropenic patients and their resistance to antibiotics].although gram negative as well as gram positive bacteria participate in febrile episodes of neutropenic patients, in particular recently the ratio of gram positive bacteria is increasing. the objective of the present work was to investigate the incidence and antibiotic resistance of pathogenic bacterial agents in neutropenic patients.19989511277
cloning and sequencing of a 2,5-dichlorohydroquinone reductive dehalogenase gene whose product is involved in degradation of gamma-hexachlorocyclohexane by sphingomonas paucimobilis.sphingomonas (formerly pseudomonas) paucimobilis ut26 utilizes gamma-hexachlorocyclohexane (gamma-hch), a halogenated organic insecticide, as a sole carbon and energy source. in a previous study, we showed that gamma-hch is degraded to 2,5-dichlorohydroquinone (2,5-dchq) (y. nagata, r. ohtomo, k. miyauchi, m. fukuda, k. yano, and m. takagi, j. bacteriol. 176:3117-3125, 1994). in the present study, we cloned and characterized a gene, designated lind, directly involved in the degradation of 2,5-dc ...19989515900
pcau, a transcriptional activator of genes for protocatechuate utilization in acinetobacter.the acinetobacter pcaijfbdkchg operon encodes the six enzymes that convert protocatechuate to citric acid cycle intermediates. directly downstream from the operon are qui and pob genes encoding sets of enzymes that convert quinate and p-hydroxybenzoate, respectively, to protocatechuate. prior to this investigation, the only known regulatory gene in the pca-qui-pob cluster was pobr, which encodes a transcriptional activator that responds to p-hydroxybenzoate and activates transcription of poba. t ...19989515921
identification and characterization of a novel competence gene, comc, required for dna binding and uptake in acinetobacter sp. strain bd413.a gene (comc) essential for natural transformation was identified in acinetobacter sp. strain bd413. comc has a typical leader sequence and is similar to different type iv pilus assembly factors. a comc mutant (t308) is not able to bind or take up dna but exhibits a piliation phenotype indistinguishable from the transformation wild type as revealed by electron microscopy.19989515934
in vitro and in vivo antibacterial activities of cs-834, a new oral carbapenem.cs-834 is a prodrug of the carbapenem r-95867, developed by sankyo co., ltd., tokyo, japan. to investigate the possibility that cs-834 may be the first carbapenem usable in an oral dosage form, its in vitro antibacterial activity (as r-95867) and in vivo antibacterial activity were compared with those of cefpodoxime proxetil, cefditoren pivoxil, cefdinir, ofloxacin, imipenem, and amoxicillin. r-95867 had high levels of activity against methicillin-susceptible staphylococci and streptococci, incl ...19989517932
antimicrobial activity of novel furanonaphthoquinone analogs.analogs of furanonaphthoquinone (fnq) from tecoma ipe mart had mics ranging from 1.56 to 25 microg/ml against gram-positive bacteria. fnq showed significantly lower mics against methicillin-resistant staphylococcus aureus than against methicillin-sensitive s. aureus. fnq inhibited helicobacter pylori with an mic of 0.1 microg/ml. fungi, including pathogenic species, were sensitive to fnq with mics similar to those of amphotericin b.19989517956
the acinetobacter calcoaceticus ncib8250 mop operon mrna is differentially degraded, resulting in a higher level of the 3' cata-encoding segment than of the 5' phenolhydroxylase-encoding portion.the 7.5-kb polycistronic mop mrna is differentially degraded in acinetobacter calcoaceticus. the 4.9-kb 5' portion of the transcript contains the genes mopklmnop, encoding the multi-component phenol hydroxylase, and its 5' end decays three times faster than the 2.3-kb 3' portion encoding catechol 1,2-dioxygenase (cata). larger amounts of the cata mrna than the mopklmnop mrna are present in the cells as a result of this processing. the site for endonucleolytic cleavage is located in the intercist ...19989520267
immunoreactivity of five monoclonal antibodies against the 37-kilodalton common cell wall protein (psaa) of streptococcus pneumoniae.five monoclonal antibodies (mabs) were produced against the streptococcus pneumoniae pneumococcal surface adhesin a (psaa) 37-kda common cell wall protein. these antibodies were used in a dot immunoblot and western blot study of clinical isolates of s. pneumoniae to detect the presence of the protein. by both assays, the mabs reacted with clinical isolates representing the 23 type-specific serotypes present in the licensed pneumococcal polysaccharide vaccine. western blot analysis confirmed the ...19989521144
the rhizobium etli rpon locus: dna sequence analysis and phenotypical characterization of rpon, ptsn, and ptsa mutants.the rpon region of rhizobium etli was isolated by using the bradyrhizobium japonicum rpon1 gene as a probe. nucleotide sequence analysis of a 5,600-bp dna fragment of this region revealed the presence of four complete open reading frames (orfs), orf258, rpon, orf191, and ptsn, coding for proteins of 258, 520, 191, and 154 amino acids, respectively. the gene product of orf258 is homologous to members of the atp-binding cassette-type permeases. orf191 and ptsn are homologous to conserved orfs foun ...19989537369
occurrence of homologs of the escherichia coli lytb gene in gram-negative bacterial species.the escherichia coli lytb protein regulates the activity of guanosine 3',5'-bispyrophosphate synthetase i (rela). a southern blot analysis of chromosomal dna with the e. coli lytb gene as a probe revealed the presence of lytb homologs in all of the gram-negative bacterial species examined but not in gram-positive species. the lytb homologs from enterobacter aerogenes and pseudomonas fluorescens complemented the e. coli lytb44 mutant allele.19989537400
alkane hydroxylase from acinetobacter sp. strain adp1 is encoded by alkm and belongs to a new family of bacterial integral-membrane hydrocarbon hydroxylases.degradation of long-chain alkanes by acinetobacter sp. strain adp1 involves rubredoxin and rubredoxin reductase. we complemented a mutant deficient in alkane utilization and sequenced four open reading frames (orfs) on the complementing dna. each of these orfs was disrupted by insertional mutagenesis on the chromosome. as determined from sequence comparisons, orf1 and orf4 seem to encode a rotamase of the ppic type and an acyl coenzyme a dehydrogenase, respectively. disruption of these orfs does ...19989546151
self-transmissible mercury resistance plasmids with gene-mobilizing capacity in soil bacterial populations: influence of wheat roots and mercury addition.a set of mercury resistance plasmids was obtained from wheat rhizosphere soil amended or not amended with mercuric chloride via exogenous plasmid isolation by using pseudomonas fluorescens r2f, pseudomonas putida uwc1, and enterobacter cloacae be1 as recipient strains. the isolation frequencies were highest from soil amended with high levels of mercury, and the isolation frequencies from unamended soil were low. with p. putida uwc1 as the recipient, the isolation frequency was significantly enha ...19989546155
transformation of acinetobacter sp. strain bd413 by transgenic sugar beet dna.the ability of acinetobacter sp. strain bd413(pfg4 delta nptii) to take up and integrate transgenic plant dna based on homologous recombination was studied under optimized laboratory conditions. restoration of nptii, resulting in kanamycin-resistant transformants, was observed with plasmid dna, plant dna, and homogenates carrying the gene nptii. molecular analysis showed that some transformants not only restored the 317-bp deletion but also obtained additional dna.19989546192
the tfdk gene product facilitates uptake of 2,4-dichlorophenoxyacetate by ralstonia eutropha jmp134(pjp4).uptake of 2,4-dichlorophenoxyacetate (2,4-d) by ralstonia eutropha jmp134(pjp4) was studied and shown to be an energy-dependent process. the uptake system was inducible with 2,4-d and followed saturation kinetics in a concentration range of up to 60 microm, implying the involvement of a protein in the transport process. we identified an open reading frame on plasmid pjp4, which was designated tfdk, whose translation product tfdk was highly hydrophobic and showed resemblance to transport proteins ...19989555911
oxidation of methyl-substituted naphthalenes: pathways in a versatile sphingomonas paucimobilis strainaromatic compounds with alkyl substituents are abundant in fossil fuels. these compounds become important environmental sources of soluble toxic products, developmental inhibitors, etc. principally through biological activities. to assess the effect of methyl substitution on the completeness of mineralization and accumulation of pathway products, an isolate from a phenanthrene enrichment culture, sphingomonas paucimobilis 2322, was used. washed cell suspensions containing cells grown on 2,6-dime ...19989572967
identification and characterization of a new organic hydroperoxide resistance (ohr) gene with a novel pattern of oxidative stress regulation from xanthomonas campestris pv. phaseoli.we have isolated a new organic hydroperoxide resistance (ohr) gene from xanthomonas campestris pv. phaseoli. this was done by complementation of an escherichia coli alkyl hydroperoxide reductase mutant with an organic hydroperoxide-hypersensitive phenotype. ohr encodes a 14.5-kda protein. its amino acid sequence shows high homology with several proteins of unknown function. an ohr mutant was subsequently constructed, and it showed increased sensitivity to both growth-inhibitory and killing conce ...19989573147
regulation of benzoate degradation in acinetobacter sp. strain adp1 by benm, a lysr-type transcriptional acinetobacter sp. strain adp1, benzoate degradation requires the ben genes for converting benzoate to catechol and the cat genes for degrading catechol. here we describe a novel transcriptional activator, benm, that regulates the chromosomal ben and cat genes. benm is homologous to catm, a lysr-type transcriptional activator of the cat genes. unusual regulatory features of this system include the abilities of both benm and catm to recognize the same inducer, cis,cis-muconate, and to regulate ...19989573203
a gene cluster encoding steps in conversion of naphthalene to gentisate in pseudomonas sp. strain u2.pseudomonas sp. strain u2 was isolated from oil-contaminated soil in venezuela by selective enrichment on naphthalene as the sole carbon source. the genes for naphthalene dioxygenase were cloned from the plasmid dna of strain u2 on an 8.3-kb bamhi fragment. the genes for the naphthalene dioxygenase genes nagaa (for ferredoxin reductase), nagab (for ferredoxin), and nagac and nagad (for the large and small subunits of dioxygenase, respectively) were located by southern hybridizations and by nucle ...19989573207
specificity of rabbit antisera against lipopolysaccharide of acinetobacter.acinetobacter has been reported to be involved in hospital-acquired infections with increasing frequency. however, clinical laboratories still lack simple methods that allow the accurate identification of acinetobacter strains at the species level. for this study, proteinase k-digested whole-cell lysates from 44 clinical and environmental isolates were investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting with hyperimmune rabbit sera to examine the possibil ...19989574685
identification of acinetobacters on blood agar in presence of d-glucose by unique browning effect.a positive phenotypic characteristic of glucose-oxidizing acinetobacters was demonstrated with blood agar containing d-glucose. glucose-oxidizing acinetobacter baumannii, acinetobacter genospecies 3, acinetobacter lwoffii, and acinetobacter genospecies 13 sensu tjernberg and ursing caused a unique brown discoloration of media supplemented with 5% blood (of horse, sheep, or human origin) and an aldose sugar (0.22 m d-glucose, d-galactose, d-mannose, d-xylose, or lactose). the browning effect was ...19989574714
lys42 and ser42 variants of p-hydroxybenzoate hydroxylase from pseudomonas fluorescens reveal that arg42 is essential for nadph binding.the conserved arg42 of the flavoprotein p-hydroxybenzoate hydroxylase is located at the entrance of the active site in a loop between helix h2 and sheet e1 of the fad-binding domain. replacement of arg42 by lys or ser decreases the turnover rate of p-hydroxybenzoate hydroxylase from pseudomonas fluorescens by more than two orders of magnitude. rapid reaction kinetics show that the low activity of the arg42 variants results from impaired binding of nadph. in contrast to an earlier conclusion draw ...19989578477
reconstitution of membrane-integrated quinoprotein glucose dehydrogenase apoenzyme with pqq and the holoenzyme's mechanism of action.membrane-integrated quinoprotein glucose dehydrogenase from acinetobacter calcoaceticus was produced by heterologous expression of the gene for it in an escherichia coli recombinant strain. the apoenzyme (lacking the cofactor pyrroloquinoline quinone, pqq) was solubilized with triton x-100 and purified to homogeneity. reconstitution of the apoenzyme to full activity in the assay was achieved with a stoichiometric amount of pqq in the presence of mg2+. just as for other pqq-containing dehydrogena ...19989578566
characterization of bradyrhizobium japonicum pcabdc genes involved in 4-hydroxybenzoate degradation.the pca structural genes encode enzymes that participate in the conversion of protocatechuate to succinate and acetylcoenzyme a. a 3. 05-kb region of the bradyrhizobium japonicum strain usda110 genome has been characterized, which contains the pcab, pcad and pcac genes. the predicted protein sequences of the three genes have extensive homologies with beta-carboxy-cis,cis-muconate cycloisomerase (pcab), beta-ketodiapate enol-lactone hydrolase (pcad), and gamma-carboxymuconolactone decarboxylase ( ...19989582432
interactions of beta-lactamases with sanfetrinem (gv 104326) compared to those with imipenem and with oral beta-lactams.sanfetrinem is a trinem beta-lactam which can be administered orally as a hexatil ester. we examined whether its beta-lactamase interactions resembled those of the available carbapenems, i.e., stable to ampc and extended-spectrum beta-lactamases but labile to class b and functional group 2f enzymes. the comparator drugs were imipenem, oral cephalosporins, and amoxicillin. mics were determined for beta-lactamase expression variants, and hydrolysis was examined directly with representative enzymes ...19989593145
[development of resistance and utilization of fluoroquinolones in a university hospital].the results of a retrospective study in the faculty hospital, hradec králové (fhhk) show a steep increase in the consumption of fluoroquinolones in the course of six years. since 1989, when 360 defined daily doses (ddd) were administered, the consumption increased to 2,825 ddds in 1992 and 52,162 ddds in 1995. at the same time, resistance to ofloxacine and ciprofloxacine was increased many times in some bacterial species isolated from patients admitted to fhhk. in the strains pseudomonas aerugin ...19979600142
imipenem resistance in aerobic gram-negative bacteria.a prospective study was undertaken to observe the emergence of resistance to imipenem, if any, among aerobic gram-negative bacteria. a total of 736 isolates were tested during 1994-95 and less than 1% of them were resistant to imipenem, whereas the next year ('95-'96) the rate increased to 11 of the 903 isolates tested. the resistant isolates during '94-'95 were all stenotrophomonas maltophilia whereas the spectrum of resistant bacterial species increased in '95-'96 to include pseudomonas aerugi ...19989603633
characterization of the hca cluster encoding the dioxygenolytic pathway for initial catabolism of 3-phenylpropionic acid in escherichia coli k-12.we have identified, cloned, and sequenced the hca cluster encoding the dioxygenolytic pathway for initial catabolism of 3-phenylpropionic acid (pp) in escherichia coli k-12. this cluster maps at min 57.5 of the chromosome and is composed of five catabolic genes arranged as a putative operon (hcaa1a2cbd) and two additional genes transcribed in the opposite direction that encode a potential permease (hcat) and a regulator (hcar). sequence comparisons revealed that while hcaa1a2cd genes encode the ...19989603882
identification of the gene encoding the tryptophan synthase beta-subunit from chlamydomonas reinhardtii.we report the isolation of a chlamydomonas reinhardtii cdna that encodes the beta-subunit of tryptophan synthase (tsb). this cdna was cloned by functional complementation of a trp-operon-deleted strain of escherichia coli. hybridization analysis indicated that the gene exists in a single copy. the predicted amino acid sequence showed the greatest identity to tsb polypeptides from other photosynthetic organisms. with the goal of identifying mutations in the gene encoding this enzyme, we isolated ...19989625698
identification and sequence analysis of a 27-kilobase chromosomal fragment containing a salmonella pathogenicity island located at 92 minutes on the chromosome map of salmonella enterica serovar typhimurium lt2.using a genomic approach, we have identified a new salmonella pathogenicity island, spi-4, which is the fourth salmonella pathogenicity island to be identified. spi-4 was located at 92 min on the chromosome map and was flanked by the ssb and soxsr loci. the dna sequence covering the entire spi-4 and both boundaries was determined. the size of spi-4 was about 25 kb and it contains 18 putative open reading frames (orfs). three of these orfs encode proteins that have significant homology with prote ...19989632606
isolation and entomotoxic properties of the xenorhabdus nematophilus f1 lecithinase.xenorhabdus spp. and photorhabdus spp., entomopathogenic bacteria symbiotically associated with nematodes of the families steinernematidae and heterorhabditidae, respectively, were shown to produce different lipases when they were grown on suitable nutrient agar. substrate specificity studies showed that photorhabdus spp. exhibited a broad lipase activity, while most of the xenorhabdus spp. secreted a specific lecithinase. xenorhabdus spp. occur spontaneously in two variants, phase i and phase i ...19989647801
aerobic mineralization of 2,6-dichlorophenol by ralstonia sp. strain rk1.a new aerobic bacterium was isolated from the sediment of a freshwater pond close to a contaminated site at amponville (france). it was enriched in a fixed-bed reactor fed with 2,6-dichlorophenol (2,6-dcp)as the sole carbon and energy source at ph 7.5 and room temperature. the degradation of 2,6-dcp followed monod kinetics at low initial concentrations. at concentrations above 300 microm (50 mg.liter-1), 2,6-dcp increasingly inhibited its own degradation. the base sequence of the 16s ribosomal d ...19989647831
biodegradation of variable-chain-length alkanes at low temperatures by a psychrotrophic rhodococcus sp.the psychorotrophic rhodococcus sp. strain q15 was examined for its ability to degrade individual n-alkanes and diesel fuel at low temperatures, and its alkane catabolic pathway was investigated by biochemical and genetic techniques. at 0 and 5 degrees c, q15 mineralized the short-chain alkanes dodecane and hexadecane to a greater extent than that observed for the long-chain alkanes octacosane and dotriacontane. q15 utilized a broad range of aliphatics (c10 to c21 alkanes, branched alkanes, and ...19989647833
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