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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
a fluorescent gram stain for flow cytometry and epifluorescence microscopy.the fluorescent nucleic acid binding dyes hexidium iodide (hi) and syto 13 were used in combination as a gram stain for unfixed organisms in suspension. hi penetrated gram-positive but not gram-negative organisms, whereas syto 13 penetrated both. when the dyes were used together, gram-negative organisms were rendered green fluorescent by syto 13; conversely, gram-positive organisms were rendered red-orange fluorescent by hi, which simultaneously quenched syto 13 green fluorescence. the technique ...19989647848
survival of acinetobacter baumannii on dry surfaces: comparison of outbreak and sporadic isolates.acinetobacter spp. are important nosocomial pathogens reported with increasing frequency in outbreaks of cross-infection during the past 2 decades. the majority of such outbreaks are caused by acinetobacter baumannii. to investigate whether desiccation tolerance may be involved in the ability of certain strains of a. baumannii to cause hospital outbreaks, a blind study was carried out with 39 epidemiologically well-characterized clinical isolates of a. baumannii for which survival times were det ...19989650940
reconstituted recombinant factor viii can be safely infused continuously for at least three days: it is a poor microbial growth medium.reconstituted recombinant factor viii (fviiirec) loses little biologic activity at room temperature for up to seven days and continuous infusion is convenient, effective hemostatically and requires less fviiirec concentrate than treatment by conventional bolus injections. however, the potential for bacterial contamination, with proliferation to high levels that can cause bacteremia, is a concern with continuous infusion. we studied the growth properties at 4, 25 and 35 degrees c in reconstituted ...19989663704
further studies of transferable antibiotic resistance in strains of pseudomonas aeruginosa from four clinical settings in three countries.this paper describes transferability of antibiotic resistance determinants in clinical isolates of pseudomonas aeruginosa resistant to imipenem, cefotaxime and ceftazidime obtained from different clinical settings in three different countries. two strains of enterobacteriaceae (escherichia coli k-12 and proteus mirabilis p-38) and two strains of p. aeruginosa (pao and ml) were used as recipient strains. the conjugative transfer of resistance was very specific, i.e. donor strains of p. aeruginosa ...19989669646
molecular evolution of a pathogenicity island from enterohemorrhagic escherichia coli o157:h7.we report the complete 43,359-bp sequence of the locus of enterocyte effacement (lee) from edl933, an enterohemorrhagic escherichia coli o157:h7 serovar originally isolated from contaminated hamburger implicated in an outbreak of hemorrhagic colitis. the locus was isolated from the edl933 chromosome with a homologous-recombination-driven targeting vector. recent completion of the lee sequence from enteropathogenic e. coli (epec) e2348/69 afforded the opportunity for a comparative analysis of the ...19989673266
genetic analysis of dioxin dioxygenase of sphingomonas sp. strain rw1: catabolic genes dispersed on the genome.the dioxin dioxygenase of sphingomonas sp. strain rw1 activates dibenzo-p-dioxin and dibenzofuran for further metabolism by introducing two atoms of oxygen at a pair of vicinal carbon atoms, one of which is involved in one of the bridges between the two aromatic rings, i.e., an angular dioxygenation. the dxna1 and dxna2 cistrons encoding this dioxygenase have been cloned and shown to be located just upstream of a hydrolase gene which specifies an enzyme involved in the subsequent step of the dib ...19989683494
structure of carb-4 and aer-1 carbenicillin-hydrolyzing beta-lactamases.we determined the nucleotide sequences of blacarb-4 encoding carb-4 and deduced a polypeptide of 288 amino acids. the gene was characterized as a variant of group 2c carbenicillin-hydrolyzing beta-lactamases such as pse-4, pse-1, and carb-3. the level of dna homology between the bla genes for these beta-lactamases varied from 98.7 to 99.9%, while that between these genes and blacarb-4 encoding carb-4 was 86.3%. the blacarb-4 gene was acquired from some other source because it has a g+c content o ...19989687391
spatial and temporal deposition of hyphomonas strain vp-6 capsules involved in biofilm formationhyphomonas strain vp-6 is a prosthecate bacterium isolated from the guayamas vent region and is a member of a genus of primary and common colonizers of marine surfaces. it adheres to solid substrata as a first step in biofilm formation. fine-structure microscopy and the use of specific stains and lectins reveal that it synthesizes two different extracellular polymeric substances (eps). one is a temporally synthesized, polar holdfast eps, and the other is a capsular eps that is present during the ...19989687449
negative cooperativity in the steady-state kinetics of sugar oxidation by soluble quinoprotein glucose dehydrogenase from acinetobacter calcoaceticus.steady-state-kinetics investigations were carried out for the oxidation of aldose sugars by soluble quinoprotein glucose dehydrogenase (gdh) from acinetobacter calcoaceticus using n-methylphenazonium methyl sulfate (pms) as artificial electron acceptor. as is not uncommon for a dye-linked dehydrogenase, the enzyme showed ping-pong behaviour and double-substrate inhibition. however, under conditions that avoided its masking by sugar-substrate inhibition as much as possible, negative kinetic coope ...19989692926
biochemical and genetic characterization of a gentisate 1, 2-dioxygenase from sphingomonas sp. strain rw5.a 4,103-bp long dna fragment containing the structural gene of a gentisate 1,2-dioxygenase (ec 1.13.11.4), gtda, from sphingomonas sp. strain rw5 was cloned and sequenced. the gtda gene encodes a 350-amino-acid polypeptide with a predicted size of 38.85 kda. comparison of the gtda gene product with protein sequences in databases, including those of intradiol or extradiol ring-cleaving dioxygenases, revealed no significant homology except for a low similarity (27%) to the 1-hydroxy-2-naphthoate d ...19989696766
one of two osmc homologs in bacillus subtilis is part of the sigmab-dependent general stress regulon.in this report we present the identification and analysis of two bacillus subtilis genes, ykla and ykza, which are homologous to the partially rpos-controlled osmc gene from escherichia coli. the ykla gene is expressed at higher levels in minimal medium than in rich medium and is driven by a putative vegetative promoter. expression of ykza is not medium dependent but increases dramatically when cells are exposed to stress and starvation. this stress-induced increase in ykza expression is absolut ...19989696771
changing bacterial ecology during a five-year period of selective intestinal decontamination.the development of bacterial resistance during selective decontamination of the digestive tract (sdd) is controversial. we studied effects on bacterial resistance one year before and during a randomized, placebo-controlled trial of sdd in a surgical intensive care unit. we randomized patients within two different topical regimens (pta, pca) or placebo, administered four-times daily to both the oropharynx and gastrointestinal tract. all patients received intravenous ciprofloxacin (200 mg b.d.) fo ...19989699139
comparison of amplified ribosomal dna restriction analysis, random amplified polymorphic dna analysis, and amplified fragment length polymorphism fingerprinting for identification of acinetobacter genomic species and typing of acinetobacter baumannii.thirty-one strains of acinetobacter species, including type strains of the 18 genomic species and 13 clinical isolates, were compared by amplified ribosomal dna restriction analysis (ardra), random amplified polymorphic dna analysis (rapd), and amplified fragment length polymorphism (aflp) fingerprinting. ardra, performed with five different enzymes, showed low discriminatory power for differentiating acinetobacter at the species and strain level. the standardized commercially available rapd kit ...19989705386
resistance mechanisms in pseudomonas aeruginosa and other nonfermentative gram-negative bacteria.nonfermentative gram-negative bacilli are still a major concern in compromised individuals. by far the most important of these organisms is pseudomonas aeruginosa, although acinetobacter baumannii (previously acinetobacter calcoaceticus), stenotrophomonas maltophilia (previously pseudomonas and xanthomonas maltophilia), and burkholderia cepacia (previously pseudomonas cepacia) are also of substantative concern because of their similar high intrinsic resistances to antibiotics. the basis for the ...19989710677
a cluster of genes involved in polysaccharide biosynthesis from enterococcus faecalis og1rf.our previous work identified a cosmid clone containing a 43-kb insert from enterococcus faecalis og1rf that produced a nonprotein antigen in escherichia coli. in the present work, we studied this clone in detail. periodate treatment of lysates of the clone confirmed that the antigen was carbohydrate in nature. analysis of dna sequences and transposon insertion mutants suggested that the insert contained a multicistronic gene cluster. database comparison showed that the cluster contained genes si ...19989712783
parallel and divergent genotypic evolution in experimental populations of ralstonia sp.genetic rearrangements within a population of bacteria were analyzed to understand the degree of divergence occurring after experimental evolution. we used 18 replicate populations founded from ralstonia sp. strain tfd41 that had been propagated for 1,000 generations with 2,4-dichlorophenoxyacetic acid (2,4-d) as the carbon source. genetic divergence was examined by restriction fragment length polymorphism analysis of the incumbent plasmid that carries the 2,4-d catabolic genes and by amplificat ...19989721265
purification and characterization of the coniferyl aldehyde dehydrogenase from pseudomonas sp. strain hr199 and molecular characterization of the gene.the coniferyl aldehyde dehydrogenase (caldh) of pseudomonas sp. strain hr199 (dsm7063), which catalyzes the nad+-dependent oxidation of coniferyl aldehyde to ferulic acid and which is induced during growth with eugenol as the carbon source, was purified and characterized. the native protein exhibited an apparent molecular mass of 86,000 +/- 5,000 da, and the subunit mass was 49.5 +/- 2.5 kda, indicating an alpha2 structure of the native enzyme. the optimal oxidation of coniferyl aldehyde to feru ...19989721273
similarities between the antabc-encoded anthranilate dioxygenase and the benabc-encoded benzoate dioxygenase of acinetobacter sp. strain adp1.acinetobacter sp. strain adp1 can use benzoate or anthranilate as a sole carbon source. these structurally similar compounds are independently converted to catechol, allowing further degradation to proceed via the beta-ketoadipate pathway. in this study, the first step in anthranilate catabolism was characterized. a mutant unable to grow on anthranilate, acn26, was selected. the sequence of a wild-type dna fragment that restored growth revealed the antabc genes, encoding 54-, 19-, and 39-kda pro ...19989721284
substrate specificity of and product formation by muconate cycloisomerases: an analysis of wild-type enzymes and engineered variants.muconate cycloisomerases play a crucial role in the bacterial degradation of aromatic compounds by converting cis,cis-muconate, the product of catechol ring cleavage, to (4s)-muconolactone. chloromuconate cycloisomerases catalyze both the corresponding reaction and a dehalogenation reaction in the transformation of chloroaromatic compounds. this study reports the first thorough examination of the substrate specificity of the muconate cycloisomerases from pseudomonas putida prs2000 and acinetobac ...19989726873
antibiotic resistance in acinetobacter spp. isolated from sewers receiving waste effluent from a hospital and a pharmaceutical plant.the possible increase of antibiotic-resistant bacteria in sewage associated with the discharge of wastewater from a hospital and a pharmaceutical plant was investigated by using acinetobacter species as environmental bacterial indicators. the level of susceptibility to six antimicrobial agents was determined in 385 acinetobacter strains isolated from samples collected upstream and downstream from the discharge points of the hospital and the pharmaceutical plant. results indicated that while the ...19989726904
insertion sequences.insertion sequences (iss) constitute an important component of most bacterial genomes. over 500 individual iss have been described in the literature to date, and many more are being discovered in the ongoing prokaryotic and eukaryotic genome-sequencing projects. the last 10 years have also seen some striking advances in our understanding of the transposition process itself. not least of these has been the development of various in vitro transposition systems for both prokaryotic and eukaryotic e ...19989729608
direct antimicrobial susceptibility testing of gram-negative bacilli in blood cultures by an electrochemical method.nonfastidious aerobic gram-negative bacilli (gnb) are commonly isolated from blood cultures. the feasibility of using an electrochemical method for direct antimicrobial susceptibility testing of gnb in positive blood cultures was evaluated. an aliquot (10 microliter) of 1:10-diluted positive blood cultures containing gnb was inoculated into the bactometer module well (biomérieux vitek, hazelwood, mo.) containing 1 ml of mueller-hinton broth supplemented with an antibiotic. susceptibility tests w ...19989738038
total nutrient admixtures appear safer than lipid emulsion alone as regards microbial contamination: growth properties of microbial pathogens at room temperature.the extraordinary growth properties of most microorganisms in 10% and 20% lipid emulsions has led to the centers for disease control and prevention recommendation that if lipids are given through an i.v. line, the administration set should be replaced every 24 hours rather than the usual 72-hour interval used for crystalloid solutions, including those used for conventional total parenteral nutrition. for nearly 15 years, parenteral alimentation has been given as a total nutrient admixture (tna), ...19989739032
a role for a protease in morphogenic responses during yeast cell fusion.cell fusion during yeast mating provides a model for signaling-controlled changes at the cell surface. we identified the axl1 gene in a screen for genes required for cell fusion in both mating types during mating. axl1 is a pheromone-inducible gene required for axial bud site selection in haploid yeast and for proteolytic maturation of a-factor. two other bud site selection genes, rsr1, encoding a small gtpase, and bud3, were also required for efficient cell fusion. based on double mutant analys ...19989744878
dna sequencing and analysis of the low-ca2+-response plasmid pcd1 of yersinia pestis kim5.the low-ca2+-response (lcr) plasmid pcd1 of the plague agent yersinia pestis kim5 was sequenced and analyzed for its genetic structure. pcd1 (70,509 bp) has an incfiia-like replicon and a sopabc-like partition region. we have assigned 60 apparently intact open reading frames (orfs) that are not contained within transposable elements. of these, 47 are proven or possible members of the lcr, a major virulence property of human-pathogenic yersinia spp., that had been identified previously in one or ...19989746557
[assessment of a new four-hour diagnostic kit--rapid one system for the identification of enteric bacteria].rapid one system is a newly developed four-hour rapid diagnostic kit for the identification of enteric bacteria. to know the effectiveness of this system, we used 125 strains of oxidase-negative, gram-negative bacilli for this evaluation. except for acinetobacter calcoaceticus, all the bacilli belong to family enterobacteriaceae. the bacterial strains of this assessment belong to 12 genera and 20 species. among them, 84 strains were freshly isolated from clinical specimens and 41 strains were fr ...19949747343
mutation analysis of pobr and pcau, closely related transcriptional activators in acinetobacter.acinetobacter pobr and pcau are transcriptional activators that closely resemble each other in primary structure, dna-binding sites, metabolic modulators, and physiological function. pobr responds to the inducer-metabolite p-hydroxybenzoate and activates transcription of poba, the structural gene for the enzyme that converts p-hydroxybenzoate to protocatechuate. this compound, differing from p-hydroxybenzoate only in that it contains an additional oxygen atom, binds to pcau and thereby specifica ...19989748437
formation of single-stranded dna during dna transformation of neisseria gonorrhoeae.neisseria gonorrhoeae is naturally competent for dna transformation. in contrast to other natural prokaryotic dna transformation systems, single-stranded donor dna (ssdna) has not previously been detected during transformation of n. gonorrhoeae. we have reassessed the physical nature of gonococcal transforming dna by using a sensitive nondenaturing native blotting technique that detects ssdna. consistent with previous analyses, we found that the majority of donor dna remained in the double-stran ...19989748444
characterization of is18, an element capable of activating the silent aac(6')-ij gene of acinetobacter sp. 13 strain bm2716 by transposition.insertion sequence is18 was detected by analysis of the spontaneous aminoglycoside resistant mutant acinetobacter sp. 13 strain bm2716-1. insertion of the element upstream from the silent acetyltransferase gene aac(6')-ij created a hybrid promoter that putatively accounts for the expression of the aminoglycoside resistance gene. the 1, 074-bp is18 element contained partially matched (20 out of 26 bases) terminal inverted repeats, one of which overlapped the 3' end of a 935-bp open reading frame ...19989756793
analysis of the gene cluster encoding toluene/o-xylene monooxygenase from pseudomonas stutzeri ox1.the toluene/o-xylene monooxygenase cloned from pseudomonas stutzeri ox1 displays a very broad range of substrates and a very peculiar regioselectivity, because it is able to hydroxylate more than one position on the aromatic ring of several hydrocarbons and phenols. the nucleotide sequence of the gene cluster coding for this enzymatic system has been determined. the sequence analysis revealed the presence of six open reading frames (orfs) homologous to other genes clustered in operons coding for ...19989758777
enhanced utilization of phosphonate and phosphite by klebsiella aerogenes.klebsiella aerogenes atcc 9621 was able to utilize phosphonates (pn), including aminoethylphosphonate, ethylphosphonate, methylphosphonate (mpn), and phosphonoacetate, and inorganic phosphite (pt) as sole sources of phosphorus (p). the products of the phn gene cluster were absolutely required for pn breakdown and pt oxidation to inorganic phosphate (pi) in this organism. to determine if k. aerogenes atcc 9621 could be engineered to enhance the utilization of pn and pt, a multicopy plasmid, pbi05 ...19989758795
characterization of genes involved in biosynthesis of a novel antibiotic from burkholderia cepacia bc11 and their role in biological control of rhizoctonia solani.genetic manipulation of fluorescent pseudomonads has provided major insight into their production of antifungal molecules and their role in biological control of plant disease. burkholderia cepacia also produces antifungal activities, but its biological control activity is much less well characterized, in part due to difficulties in applying genetic tools. here we report genetic and biochemical characterization of a soil isolate of b. cepacia relating to its production of an unusual antibiotic t ...19989758823
intermediates of salicylic acid biosynthesis in tobaccosalicylic acid (sa) is an important component of systemic-acquired resistance in plants. it is synthesized from benzoic acid (ba) as part of the phenylpropanoid pathway. benzaldehyde (bd), a potential intermediate of this pathway, was found in healthy and tobacco mosaic virus (tmv)-inoculated tobacco (nicotiana tabacum l. cv xanthi-nc) leaf tissue at 100 ng/g fresh weight concentrations as measured by gas chromatography-mass spectrometry. bd was also emitted as a volatile organic compound from t ...19989765542
identification of chlorobenzene dioxygenase sequence elements involved in dechlorination of 1,2,4,5-tetrachlorobenzene.the teca chlorobenzene dioxygenase and the todcba toluene dioxygenase exhibit substantial sequence similarity yet have different substrate specificities. escherichia coli cells producing recombinant teca enzyme dioxygenate and simultaneously eliminate a halogen substituent from 1,2,4,5-tetrachlorobenzene but show no activity toward benzene, whereas those producing todcba dioxygenate benzene but not tetrachlorobenzene. a hybrid teca dioxygenase variant containing the large alpha-subunit of the to ...19989791099
oxygen-insensitive nitroreductases: analysis of the roles of nfsa and nfsb in development of resistance to 5-nitrofuran derivatives in escherichia coli.nitroheterocyclic and nitroaromatic compounds constitute an enormous range of chemicals whose potent biological activity has significant human health and environmental implications. the biological activity of nitro-substituted compounds is derived from reductive metabolism of the nitro moiety, a process catalyzed by a variety of nitroreductase activities. resistance of bacteria to nitro-substituted compounds is believed to result primarily from mutations in genes encoding oxygen-insensitive nitr ...19989791100
pqq as redox shuttle for quinoprotein glucose dehydrogenase.the role of pyrroloquinoline quinone (pqq) as a redox shuttle between an electrode and the active site of soluble quinoprotein glucose dehydrogenase (sgdh) from acinetobacter calcoaceticus has been investigated using both electrochemical and spectrophotometric methods. reversible redox behavior of pqq was observed at cystamine-modified gold electrodes. sgdh is able to reduce free pqq, i.e. pqq that is not bound to the enzyme and therefore could act as a mediator between the enzyme and the cystam ...19989792456
an automated fluorescent pcr method for detection of shiga toxin-producing escherichia coli in foods.an automated fluorescence-based pcr system (a model ag-9600 amplisensor analyzer) was investigated to determine whether it could detect shiga toxin-producing escherichia coli (stec). the amplisensor pcr assay involves amplification-mediated disruption of a fluorogenic dna signal duplex (amplisensor) that is homologous to conserved target sequences in a 323-bp amplified fragment of shiga toxin genes stx1, stx2, and stxe. using the amplisensor assay, we detected 113 strains of stec belonging to 50 ...19989797267
molecular detection, isolation, and physiological characterization of functionally dominant phenol-degrading bacteria in activated sludge.dna was isolated from phenol-digesting activated sludge, and partial fragments of the 16s ribosomal dna (rdna) and the gene encoding the largest subunit of multicomponent phenol hydroxylase (lmph) were amplified by pcr. an analysis of the amplified fragments by temperature gradient gel electrophoresis (tgge) demonstrated that two major 16s rdna bands (bands r2 and r3) and two major lmph gene bands (bands p2 and p3) appeared after the activated sludge became acclimated to phenol. the nucleotide s ...19989797297
expression of alkane hydroxylase from acinetobacter sp. strain adp1 is induced by a broad range of n-alkanes and requires the transcriptional activator alkr.in acinetobacter sp. strain adp1, alkane degradation depends on at least five essential genes. rubab and xcpr are constitutively transcribed. here we describe inducible transcription of alkm, which strictly depends on the presence of the transcriptional activator alkr. alkr itself is expressed at a low level, while a chromosomally located alkm::lacz fusion is inducible by middle-chain-length alkanes from heptane to undecane, which do not support growth of adp1, and by long-chain-length alkanes f ...19989811637
involvement of the terminal oxygenase beta subunit in the biphenyl dioxygenase reactivity pattern toward chlorobiphenyls.biphenyl dioxygenase (bph dox) oxidizes biphenyl on adjacent carbons to generate 2,3-dihydro-2,3-dihydroxybiphenyl in comamonas testosteroni b-356 and in pseudomonas sp. strain lb400. the enzyme comprises a two-subunit (alpha and beta) iron sulfur protein (ispbph), a ferredoxin (ferbph), and a ferredoxin reductase (redbph). b-356 bph dox preferentially catalyzes the oxidation of the double-meta-substituted congener 3,3'-dichlorobiphenyl over the double-para-substituted congener 4,4'-dichlorobiph ...19989811638
comparison of phenotypic and genotypic techniques for identification of unusual aerobic pathogenic gram-negative bacilli.rapid and accurate identification of bacterial pathogens is a fundamental goal of clinical microbiology, but one that is difficult or impossible for many slow-growing and fastidious organisms. we used identification systems based on cellular fatty acid profiles (sherlock; midi, inc., newark, del.), carbon source utilization (microlog; biolog, inc., hayward, calif.), and 16s rrna gene sequence (microseq; perkin-elmer applied biosystems division, foster city, calif.) to evaluate 72 unusual aerobic ...19989817894
identification of conserved, rpos-dependent stationary-phase genes of escherichia coli.during entry into stationary phase, many free-living, gram-negative bacteria express genes that impart cellular resistance to environmental stresses, such as oxidative stress and osmotic stress. many genes that are required for stationary-phase adaptation are controlled by rpos, a conserved alternative sigma factor, whose expression is, in turn, controlled by many factors. to better understand the numbers and types of genes dependent upon rpos, we employed a genetic screen to isolate more than 1 ...19989829938
combined physical and genetic map of the pseudomonas putida kt2440 chromosome.a combined physical and genetic map of the pseudomonas putida kt2440 genome was constructed from data obtained by pulsed-field gel electrophoresis techniques (pfge) and southern hybridization. circular genome size was estimated at 6.0 mb by adding the sizes of 19 swai, 9 pmei, 6 paci, and 6 i-ceui fragments. a complete physical map was achieved by combining the results of (i) analysis of pfge of the dna fragments resulting from digestion of the whole genome with pmei, swai, i-ceui, and paci as w ...19989829947
molecular analysis of a gene encoding a cell-bound esterase from streptomyces chrysomallus.a gene (esta) encoding a 42-kda cell-bound esterase, esta, was found to be located 75 bp upstream of the cyclophilin a gene (cypa) of streptomyces chrysomallus. western blot analysis revealed the presence of esta (42 kda) in cell extracts of s. chrysomallus x2 and streptomyces lividans. esta specifically hydrolyzes short-chain p-nitrophenyl esters. esta formation starts at the end of growth phase, and its activity level remains constant throughout stationary phase. expression of esta from the me ...19989829953
flow cytometric analysis of the in situ accessibility of escherichia coli 16s rrna for fluorescently labeled oligonucleotide probes.in situ identification of whole fixed bacterial cells by hybridization with fluorescently labeled, rrna-targeted oligonucleotide probes is often limited by low signal intensities. in addition to an impermeability of the cell periphery and a low cellular rrna content, the three-dimensional structure of the ribosome may hinder the access of oligonucleotides to their target sites. until now, a systematic study on the accessibility of 16s rrna target sites had not been done. here, we report fluoresc ...19989835591
phylogenetic affiliation of soil bacteria that degrade aliphatic polyesters available commercially as biodegradable plastics.thirty-nine morphologically different soil bacteria capable of degrading poly(beta-hydroxyalkanoate), poly(epsilon-caprolactone), poly(hexamethylene carbonate), or poly(tetramethylene succinate) were isolated. their phylogenetic positions were determined by 16s ribosomal dna sequencing, and all of them fell into the classes firmicutes and proteobacteria. determinations of substrate utilization revealed characteristic patterns of substrate specificities.19989835597
characterization of the galu gene of streptococcus pneumoniae encoding a uridine diphosphoglucose pyrophosphorylase: a gene essential for capsular polysaccharide biosynthesis.the galu gene of streptococcus pneumoniae has been cloned and sequenced. escherichia coli cells harboring the recombinant plasmid pmmg2 (galu) overproduced a protein that has been shown to correspond to a uridine 5'-triphosphate:glucose-1-phosphate uridylyltransferase (uridine diphosphoglucose [udp-glc] pyrophosphorylase) responsible for the synthesis of udp-glc, a key compound in the biosynthesis of polysaccharides. a gene very similar to the s. pneumoniae galu has been found in a partial nucle ...19989841918
novel organization of the genes for phthalate degradation from burkholderia cepacia dbo1.burkholderia cepacia dbo1 is able to utilize phthalate as the sole source of carbon and energy for growth. two overlapping cosmid clones containing the genes for phthalate degradation were isolated from this strain. subcloning and activity analysis localized the genes for phthalate degradation to two separate regions on the cosmid clones. analysis of the nucleotide sequence of these two regions showed that the genes for phthalate degradation are arranged in at least three transcriptional units. ...19989851995
the yvyd gene of bacillus subtilis is under dual control of sigmab and sigmah.during a search by computer-aided inspection of two-dimensional (2d) protein gels for sigmab-dependent general stress proteins exhibiting atypical induction profiles, a protein initially called hst23 was identified as a product of the yvyd gene of bacillus subtilis. in addition to the typical sigmab-dependent, stress- and starvation-inducible pattern, yvyd is also induced in response to amino acid depletion. by primer extension of rna isolated from the wild-type strain and appropriate mutants ca ...19989852014
rapid identification of up to three candida species in a single reaction tube by a 5' exonuclease assay using fluorescent dna probes.we used fungus-specific pcr primers and species-specific dna probes to detect up to three candida species in a single reaction tube by exploiting the 5' to 3' exonuclease activity of taq dna polymerase. probes to the internal transcribed spacer region of the rrna gene were labeled at the 5' end with one of three fluorescent reporter dyes, 6-carboxy-fluorescein (fam), tetrachloro-6-carboxy-fluorescein (tet), or hexachloro-6-carboxy-fluorescein (hex), and at the 3' end with a quencher dye, 6-carbo ...19999854084
evidence for a chemiosmotic model of dehalorespiration in desulfomonile tiedjei dcb-1.desulfomonile tiedjei dcb-1, a sulfate-reducing bacterium, conserves energy for growth from reductive dehalogenation of 3-chlorobenzoate by an uncharacterized chemiosmotic process. respiratory electron transport components were examined in d. tiedjei cells grown under conditions for reductive dehalogenation, pyruvate fermentation, and sulfate reduction. reductive dehalogenation was inhibited by the respiratory quinone inhibitor 2-heptyl-4-hydroxyquinoline n-oxide, suggesting that a respiratory q ...19999864310
genetic and biochemical characterization of a 2-pyrone-4, 6-dicarboxylic acid hydrolase involved in the protocatechuate 4, 5-cleavage pathway of sphingomonas paucimobilis syk-6.sphingomonas paucimobilis syk-6 is able to grow on a wide variety of dimeric lignin compounds with guaiacyl moieties, which are converted into protocatechuate by the actions of lignin degradation enzymes in this strain. protocatechuate is a key metabolite in the syk-6 degradation of lignin compounds with guaiacyl moieties, and it is thought that it degrades to pyruvate and oxaloacetate via the protocatechuate 4,5-cleavage pathway. in a 10.5-kb ecori fragment carrying the protocatechuate 4,5-diox ...19999864312
characterization of biosynthetic enzymes for ectoine as a compatible solute in a moderately halophilic eubacterium, halomonas elongata.1,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid (ectoine) is an excellent osmoprotectant. the biosynthetic pathway of ectoine from aspartic beta-semialdehyde (asa), in halomonas elongata, was elucidated by purification and characterization of each enzyme involved. 2,4-diaminobutyrate (daba) aminotransferase catalyzed reversively the first step of the pathway, conversion of asa to daba by transamination with l-glutamate. this enzyme required pyridoxal 5'-phosphate and potassium ions for i ...19999864317
infective endocarditis in the premature neonate.we describe a series of 11 high-risk neonates with infective endocarditis (ie) in this retrospective review. previously ie has rarely been diagnosed in newborns and is usually fatal. the frequency was 4.3 cases per 100 patients. five patients survived. microorganisms included gram positives such as s. aureus and coagulase-negative staphylococcus, gram negatives such as klebsiella pneumoniae, enterobacter cloacae, enterococcus faecalis, serratia marcescens, and acinetobacter calcoaceticus. echoca ...19989864649
fate of free dna and transformation of the oral bacterium streptococcus gordonii dl1 by plasmid dna in human saliva.competitive pcr was used to monitor the survival of a 520-bp dna target sequence from a recombinant plasmid, pvacmc1, after admixture of the plasmid with freshly sampled human saliva. the fraction of the target remaining amplifiable ranged from 40 to 65% after 10 min of exposure to saliva samples from five subjects and from 6 to 25% after 60 min of exposure. pvacmc1 plasmid dna that had been exposed to degradation by fresh saliva was capable of transforming naturally competent streptococcus gord ...19999872752
in situ, real-time catabolic gene expression: extraction and characterization of naphthalene dioxygenase mrna transcripts from groundwater.we developed procedures for isolating and characterizing in situ-transcribed mrna from groundwater microorganisms catabolizing naphthalene at a coal tar waste-contaminated site. groundwater was pumped through 0.22-microm-pore-size filters, which were then frozen in dry ice-ethanol. rna was extracted from the frozen filters by boiling sodium dodecyl sulfate lysis and acidic phenol-chloroform extraction. transcript characterization was performed with a series of pcr primers designed to amplify nah ...19999872763
plasmid-encoded anthranilate synthase (trpeg) in buchnera aphidicola from aphids of the family pemphigidae.buchnera aphidicola is an obligate intracellular symbiont of aphids. one of its proposed functions is the synthesis of essential amino acids, nutrients required by aphids but deficient in their diet of plant phloem sap. the genetic organization of the tryptophan pathway in buchnera from proliferous aphids of the family aphididae has previously been shown to reflect a capacity to overproduce this essential amino acid (c.-y. lai, l. baumann, and p. baumann, proc. natl. acad. sci. usa 91:3819-3823, ...19999872768
bacterial adhesion to soil contaminants in the presence of surfactantsit has been proposed that addition of surfactants to contaminated soil enhances the solubility of target compounds; however, surfactants may simultaneously reduce the adhesion of bacteria to hydrophobic surfaces. if the latter mechanism is important for the biodegradation of virtually insoluble contaminants, then the use of surfactants may not be beneficial. the adhesion of a mycobacterium strain and a pseudomonas strain, isolated from a creosote-contaminated soil, to the surfaces of highly visc ...19999872775
production of wax esters during aerobic growth of marine bacteria on isoprenoid compoundsthis paper describes the production of isoprenoid wax esters during the aerobic degradation of 6,10,14-trimethylpentadecan-2-one and phytol by four bacteria (acinetobacter sp. strain phy9, pseudomonas nautica [ip85/617], marinobacter sp. strain cab [dsmz 11874], and marinobacter hydrocarbonoclasticus [atcc 49840]) isolated from the marine environment. different pathways are proposed to explain the formation of these compounds. in the case of 6,10, 14-trimethylpentadecan-2-one, these esters resul ...19999872783
the alpha subunit of toluene dioxygenase from pseudomonas putida f1 can accept electrons from reduced ferredoxintol but is catalytically inactive in the absence of the beta subunit.the oxygenase component of toluene dioxygenase from pseudomonas putida f1 is an iron-sulfur protein (isptol) consisting of alpha (todc1) and beta (todc2) subunits. purified todc1 gave absorbance and electron paramagnetic resonance spectra identical to those given by purified isptol. todc1 was reduced by nadh and catalytic amounts of reductasetol and ferredoxintol. reduced todc1 did not oxidize toluene, and catalysis was strictly dependent on the presence of purified todc2.19999872799
the phn genes of burkholderia sp. strain rp007 constitute a divergent gene cluster for polycyclic aromatic hydrocarbon catabolism.cloning and molecular ecological studies have underestimated the diversity of polycyclic aromatic hydrocarbon (pah) catabolic genes by emphasizing classical nah-like (nah, ndo, pah, and dox) sequences. here we report the description of a divergent set of pah catabolic genes, the phn genes, which although isofunctional to the classical nah-like genes, show very low homology. this phn locus, which contains nine open reading frames (orfs), was isolated on an 11.5-kb hindiii fragment from phenanthre ...19999882667
a sensitive, viable-colony staining method using nile red for direct screening of bacteria that accumulate polyhydroxyalkanoic acids and other lipid storage compounds.the oxazine dye nile blue a and its fluorescent oxazone form, nile red, were used to develop a simple and highly sensitive staining method to detect poly(3-hydroxybutyric acid) and other polyhydroxyalkanoic acids (phas) directly in growing bacterial colonies. in contrast to previously described methods, these dyes were directly included in the medium at concentrations of only 0.5 microgram/ml, and growth of the cells occurred in the presence of the dyes. this allowed an estimation of the presenc ...19999914303
poly-3-hydroxybutyrate degradation in rhizobium (sinorhizobium) meliloti: isolation and characterization of a gene encoding 3-hydroxybutyrate dehydrogenase.we have cloned and sequenced the 3-hydroxybutyrate dehydrogenase-encoding gene (bdha) from rhizobium (sinorhizobium) meliloti. the gene has an open reading frame of 777 bp that encodes a polypeptide of 258 amino acid residues (molecular weight 27,177, pi 6.07). the r. meliloti bdh protein exhibits features common to members of the short-chain alcohol dehydrogenase superfamily. bdha is the first gene transcribed in an operon that also includes xdha, encoding xanthine oxidase/dehydrogenase. transc ...19999922248
characterization and nucleotide sequence of carb-6, a new carbenicillin-hydrolyzing beta-lactamase from vibrio cholerae.a clinical strain of vibrio cholerae non-o1 non-o139 isolated in france produced a new beta-lactamase with a pi of 5.35. the purified enzyme, with a molecular mass of 33,000 da, was characterized. its kinetic constants show it to be a carbenicillin-hydrolyzing enzyme comparable to the five previously reported carb beta-lactamases and to sar-1, another carbenicillin-hydrolyzing beta-lactamase that has a pi of 4.9 and that is produced by a v. cholerae strain from tanzania. this beta-lactamase is d ...19999925522
random mutagenesis by recombinational capture of pcr products in bacillus subtilis and acinetobacter calcoaceticus.we describe a general method for random mutagenesis of cloned genes by error-prone pcr or dna shuffling that eliminates the need for post-amplification subcloning following each cycle of mutagenesis. this method exploits the highly efficient and recombinogenic nature of dna uptake during natural transformation in the gram-positive bacterium bacillus subtilis and the gram-negative bacterium acinetobacter calcoaceticus. plasmid systems were designed that allow capture of pcr-amplified dna fragment ...19999927739
vig-1, a new fish gene induced by the rhabdovirus glycoprotein, has a virus-induced homologue in humans and shares conserved motifs with the moaa family.we used mrna differential display methodology to analyze the shift of transcription profile induced by the fish rhabdovirus, viral hemorrhagic septicemia virus (vhsv), in rainbow trout leukocytes. we identified and characterized a new gene which is directly induced by vhsv. this vhsv-induced gene (vig-1) encodes a 348-amino-acid protein. vig-1 is highly expressed during the experimental disease in lymphoid organs of the infected fish. intramuscular injection of a plasmid vector expressing the vi ...19999971762
spread of amikacin resistance in acinetobacter baumannii strains isolated in spain due to an epidemic strain.sixteen amikacin-resistant clinical acinetobacter baumannii isolates from nine different hospitals in spain were investigated to determine whether the high incidence of amikacin-resistant a. baumannii was due to the dissemination of an amikacin-resistant strain or to the spread of an amikacin resistance gene. the epidemiological relationship studied by repetitive extragenic palindromic pcr and low-frequency restriction analysis of chromosomal dna showed that the same clone was isolated in eight ...19999986846
phylogenetic structures of the genus acinetobacter based on gyrb sequences: comparison with the grouping by dna-dna hybridization.the phylogenetic relationships of 49 acinetobacter strains, 46 of which have previously been classified into 18 genomic species by dna-dna hybridization studies, were investigated using the nucleotide sequence of gyrb, the structural gene for the dna gyrase b subunit. the phylogenetic tree showed linkages between genomic species 1 (acinetobacter calcoaceticus), 2 (acinetobacter baumannii), 3 and tu13; genomic species 6, bj15, bj16 and bj17; genomic species 5, bj13 (synonym of tu14) and bj14; gen ...199910028249
in vitro activities of aminomethyl-substituted analogs of novel tetrahydrofuranyl carbapenems.cl 188,624, cl 190,294, and cl 191,121 are novel aminomethyl tetrahydrofuranyl (thf)-1 beta-methylcarbapenems. the in vitro antibacterial activities of these thf carbapenems were evaluated and compared with those of biapenem, imipenem, and meropenem against 554 recent clinical isolates obtained from geographically distinct medical centers across north america. the antibacterial activities of the thf carbapenems were equivalent to that of biapenem, and the thf carbapenems were slightly more activ ...199910049250
natural competence for dna transformation by legionella pneumophila and its association with expression of type iv pili.we have recently described the expression of two pili of different lengths on the surface of legionella pneumophila (b. j. stone and y. abu kwaik, infect. immun. 66:1768-1775, 1998). production of long pili requires a functional pilel locus, encoding a type iv pilin protein. since type iv pili in neisseria gonorrhoeae are associated with competence for dna transformation, we examined the competence of l. pneumophila for dna transformation under conditions that allowed the expression of type iv p ...199910049368
complete sequence of a 184-kilobase catabolic plasmid from sphingomonas aromaticivorans f199.the complete 184,457-bp sequence of the aromatic catabolic plasmid, pnl1, from sphingomonas aromaticivorans f199 has been determined. a total of 186 open reading frames (orfs) are predicted to encode proteins, of which 79 are likely directly associated with catabolism or transport of aromatic compounds. genes that encode enzymes associated with the degradation of biphenyl, naphthalene, m-xylene, and p-cresol are predicted to be distributed among 15 gene clusters. the unusual coclustering of gene ...199910049392
molecular characterization of the genes pcag and pcah, encoding protocatechuate 3,4-dioxygenase, which are essential for vanillin catabolism in pseudomonas sp. strain hr199.pseudomonas sp. strain hr199 is able to utilize eugenol (4-allyl-2-methoxyphenol), vanillin (4-hydroxy-3-methoxybenzaldehyde), or protocatechuate as the sole carbon source for growth. mutants of this strain which were impaired in the catabolism of vanillin but retained the ability to utilize eugenol or protocatechuate were obtained after nitrosoguanidine mutagenesis. one mutant (sk6169) was used as recipient of a pseudomonas sp. strain hr199 genomic library in cosmid pvk100, and phenotypic compl ...199910049847
engineering a chimeric pyrroloquinoline quinone glucose dehydrogenase: improvement of edta tolerance, thermal stability and substrate specificity.an engineered escherichia coli pqq glucose dehydrogenase (pqqgdh) with improved enzymatic characteristics was constructed by substituting and combining the gene-encoding protein regions responsible for edta tolerance, thermal stability and substrate specificity. the protein region responsible for complete edta tolerance in acinetobacter calcoaceticus, which is recognized as the indicator of high stability in co-factor binding, was elucidated. the region is located between 32 and 59% from the n-t ...199910065712
acs1 of haemophilus influenzae type a capsulation locus region ii encodes a bifunctional ribulose 5-phosphate reductase- cdp-ribitol pyrophosphorylase.the serotype-specific, 5.9-kb region ii of the haemophilus influenzae type a capsulation locus was sequenced and found to contain four open reading frames termed acs1 to acs4. acs1 was 96% identical to h. influenzae type b orf1, previously shown to have cdp-ribitol pyrophosphorylase activity (j. van eldere, l. brophy, b. loynds, p. celis, i. hancock, s. carman, j. s. kroll, and e. r. moxon, mol. microbiol. 15:107-118, 1995). low but significant homology to other pyrophosphorylases was only detec ...199910094675
molecular analysis of a novel methanesulfonic acid monooxygenase from the methylotroph methylosulfonomonas methylovora.methylosulfonomonas methylovora m2 is an unusual gram-negative methylotrophic bacterium that can grow on methanesulfonic acid (msa) as the sole source of carbon and energy. oxidation of msa by this bacterium is carried out by a multicomponent msa monooxygenase (msamo). cloning and sequencing of a 7.5-kbp sphi fragment of chromosomal dna revealed four tightly linked genes encoding this novel monooxygenase. analysis of the deduced msamo polypeptide sequences indicated that the enzyme contains a tw ...199910094704
characterization of mdcr, a regulatory gene of the malonate catabolic system in klebsiella pneumoniae.the klebsiella pneumoniae mdcr gene, which encodes a lysr-type regulator, was overexpressed in escherichia coli. purified mdcr was found to bind specifically to the control region of either the malonate decarboxylase (mdc) genes or mdcr. we have also demonstrated that mdcr is an activator of the expression of the mdc genes, whereas it represses the transcription of the putative control region of mdcr, pmdcr, indicating a negative autoregulatory control.199910094715
emergence of fosfomycin-resistant isolates of shiga-like toxin-producing escherichia coli o26.we evaluated the susceptibilities of 129 shiga-like toxin-producing escherichia coli (stec) isolates to various antibiotics. the numbers of isolates for which mics were high (> or = 128 micrograms/ml) were as follows: 5 for fosfomycin, 14 for ampicillin, 1 for cefaclor, 6 for kanamycin, 22 for tetracycline, and 2 for doxycycline. for two isolates of stec o26 mics of fosfomycin were high (1,024 and 512 micrograms/ml, respectively). conjugation experiments and glutathione s-transferase assays sugg ...199910103182
clavulanate induces expression of the pseudomonas aeruginosa ampc cephalosporinase at physiologically relevant concentrations and antagonizes the antibacterial activity of ticarcillin.although previous studies have indicated that clavulanate may induce ampc expression in isolates of pseudomonas aeruginosa, the impact of this inducer activity on the antibacterial activity of ticarcillin at clinically relevant concentrations has not been investigated. therefore, a study was designed to determine if the inducer activity of clavulanate was associated with in vitro antagonism of ticarcillin at pharmacokinetically relevant concentrations. by the disk approximation methodology, clav ...199910103195
the alkene monooxygenase from xanthobacter strain py2 is closely related to aromatic monooxygenases and catalyzes aromatic monohydroxylation of benzene, toluene, and phenol.the genes encoding the six polypeptide components of the alkene monooxygenase from xanthobacter strain py2 (xamo) have been located on a 4.9-kb fragment of chromosomal dna previously cloned in cosmid pny2. sequencing and analysis of the predicted amino acid sequences indicate that the components of xamo are homologous to those of the aromatic monooxygenases, toluene 2-, 3-, and 4-monooxygenase and benzene monooxygenase, and that the gene order is identical. the genes and predicted polypeptides a ...199910103255
effects of surfactant mixtures, including corexit 9527, on bacterial oxidation of acetate and alkanes in crude oil.mixtures of nonionic and anionic surfactants, including corexit 9527, were tested to determine their effects on bacterial oxidation of acetate and alkanes in crude oil by cells pregrown on these substrates. corexit 9527 inhibited oxidation of the alkanes in crude oil by acinetobacter calcoaceticus atcc 31012, while span 80, a corexit 9527 constituent, markedly increased the oil oxidation rate. another corexit 9527 constituent, the negatively charged dioctyl sulfosuccinate (aot), strongly reduced ...199910103264
phenotypic expression of pcr-generated random mutations in a pseudomonas putida gene after its introduction into an acinetobacter chromosome by natural transformation.localized sets of random point mutations generated by pcr amplification can be transferred efficiently to the chromosome of acinetobacter adp1 (also known as strain bd413) by natural transformation. the technique does not require cloning of pcr fragments in plasmids: pcr-amplified dna fragments are internalized by cells and directly incorporated into their genomes by homologous recombination. previously such procedures for random mutagenesis could be applied only to acinetobacter genes affording ...199910103267
dust-borne bacteria in animal sheds, schools and children's day care centres.a total of 316 bacterial strains, including psychrophiles, mesophiles and thermophiles, were isolated and identified from indoor dusts in schools, children's day care centres and animal sheds. several species which had not previously been reported from indoor environments were found: sphingomonas, brevibacterium, nocardiopsis, deinococcus and rhodococcus/gordona. a new psychrophilic actinomycete genus was also found in animal sheds, representing a new undescribed peptidoglycan type and an unusua ...199910212408
cloning and sequence analysis of the lipase and lipase chaperone-encoding genes from acinetobacter calcoaceticus rag-1, and redefinition of a proteobacterial lipase family and an analogous lipase chaperone family.the genes encoding the lipase (lipa) and lipase chaperone (lipb) from acinetobacter calcoaceticus rag-1 were cloned and sequenced. the genes were isolated from a genomic dna library by complementation of a lipase-deficient transposon mutant of the same strain. transposon insertion in this mutant and three others was mapped to a single site in the chaperone gene. the deduced amino acid (aa) sequences for the lipase and its chaperone were found to encode mature proteins of 313 aa (32.5kda) and 347 ...199910216267
a novel aromatic-ring-hydroxylating dioxygenase from the diterpenoid-degrading bacterium pseudomonas abietaniphila bkme-9.pseudomonas abietaniphila bkme-9 is able to degrade dehydroabietic acid (dha) via ring hydroxylation by a novel dioxygenase. the dita1, dita2, and dita3 genes, which encode the alpha and beta subunits of the oxygenase and the ferredoxin of the diterpenoid dioxygenase, respectively, were isolated and sequenced. the ferredoxin gene is 9. 2 kb upstream of the oxygenase genes and 872 bp upstream of a putative meta ring cleavage dioxygenase gene, ditc. a tn5 insertion in the alpha subunit gene, dita1 ...199910217753
adenosylcobalamin-mediated methyl transfer by toluate cis-dihydrodiol dehydrogenase of the tol plasmid pww0.we identified and characterized a methyl transfer activity of the toluate cis-dihydrodiol (4-methyl-3,5-cyclohexadiene-cis-1, 2-diol-1-carboxylic acid) dehydrogenase of the tol plasmid pww0 towards toluene cis-dihydrodiol (3-methyl-4,5-cyclohexadiene-cis-1, 2-diol). when the purified enzyme from the recombinant escherichia coli containing the xyll gene was incubated with toluene cis-dihydrodiol in the presence of nad+, the end products differed depending on the presence of adenosylcobalamin (coe ...199910217792
in vitro and in vivo antimicrobial activities of t-3811me, a novel des-f(6)-quinolone.the in vitro and in vivo activities of t-3811me, a novel des-f(6)-quinolone, were evaluated in comparison with those of some fluoroquinolones, including a newly developed one, trovafloxacin. t-3811, a free base of t-3811me, showed a wide range of antimicrobial spectra, including activities against chlamydia trachomatis, mycoplasma pneumoniae, and mycobacterium tuberculosis. in particular, t-3811 exhibited potent activity against various gram-positive cocci, with mics at which 90% of the isolates ...199910223917
integron- and carbenicillinase-mediated reduced susceptibility to amoxicillin-clavulanic acid in isolates of multidrug-resistant salmonella enterica serotype typhimurium dt104 from french patients.fifty-seven salmonella enterica serotype typhimurium (s. typhimurium) isolates were collected from human patients in two french hospitals, hôpital antoine béclère (clamart, france) and hôpital bicêtre (le kremlin-bicêtre, france), between 1996 and 1997. thirty of them (52 percent) were resistant to amino-, carbeni-, and ureidopenicillins, had reduced susceptibility to amoxicillin-clavulanic acid, were susceptible to cephalothin, and were resistant to sulfonamides, streptomycin, chloramphenicol, ...199910223920
adhesion of acinetobacter venetianus to diesel fuel droplets studied with in situ electrochemical and molecular probesthe adhesion of a recently described species, acinetobacter venetianus ve-c3 (f. di cello, m. pepi, f. baldi, and r. fani, res. microbiol. 148:237-249, 1997), to diesel fuel (a mixture of c12 to c28 n-alkanes) and n-hexadecane was studied and compared to that of acinetobacter sp. strain rag-1, which is known to excrete the emulsifying lipopolysaccharide, emulsan. oxygen consumption rates, biomass, cell hydrophobicity, electrophoretic mobility, and zeta potential were measured for the two strains ...199910223998
cloning and characterization of polyphosphate kinase and exopolyphosphatase genes from pseudomonas aeruginosa 8830.pseudomonas aeruginosa accumulates polyphosphates in response to nutrient limitations. to elucidate the function of polyphosphate in this microorganism, we have investigated polyphosphate metabolism by isolating from p. aeruginosa 8830 the genes encoding polyphosphate kinase (ppk) and exopolyphosphatase (ppx), which are involved in polyphosphate synthesis and degradation, respectively. the 690- and 506-amino-acid polypeptides encoded by the two genes have been expressed in escherichia coli and p ...199910224002
cloning, expression, and nucleotide sequence of the pseudomonas aeruginosa 142 ohb genes coding for oxygenolytic ortho dehalogenation of halobenzoates.we have cloned and characterized novel oxygenolytic ortho-dehalogenation (ohb) genes from 2-chlorobenzoate (2-cba)- and 2,4-dichlorobenzoate (2,4-dcba)-degrading pseudomonas aeruginosa 142. among 3,700 escherichia coli recombinants, two clones, dh5alphaf'(pod22) and dh5alphaf'(pod33), converted 2-cba to catechol and 2,4-dcba and 2,5-dcba to 4-chlorocatechol. a subclone of pod33, plasmid pe43, containing the 3,687-bp minimized ohb dna region conferred to p. putida pb2440 the ability to grow on 2- ...199910224014
identification of acinetobacter baumannii strains with monoclonal antibodies against the o antigens of their lipopolysaccharides.despite the emergence of acinetobacter baumannii strains as nosocomial pathogens, simple methods for their phenotypic identification are still unavailable. murine monoclonal antibodies specific for the o-polysaccharide moiety of the lipopolysaccharide (lps) of two a. baumannii strains were obtained after immunization with heat-killed bacteria. the monoclonal antibodies were characterized by enzyme immunoassay and by western and dot blot analyses and were investigated for their potential use for ...199910225830
acinetobacter calcoaceticus: common nosocomial organism, uncommon pathogen. 197810236786
an outbreak of acinetobacter infection associated with the use of a ventilator spirometer.although respiratory therapy equipment is a well-known source of nosocomial infection, ventilator spirometers have not been previously implicated. we report 17 acinetobacter calcoaceticus variety anitratus infections traced to contaminated spirometers. isolates from infected patients were recovered from urine, sputum, wounds, and blood. a review of attack rates for acinetobacter was prompted by a dramatic increase in blood culture isolates. prospective surveillance of intensive care environment, ...198010315086
principles and applications of methods for dna-based typing of microbial organisms. 199910325304
use of a murine o-antigen-specific monoclonal antibody to identify acinetobacter strains of unnamed genomic species 13 sensu tjernberg and ursing.a monoclonal antibody against the o-antigenic polysaccharide chain of the lipopolysaccharide (lps) of acinetobacter strains belonging to the unnamed genomic species 13 sensu tjernberg and ursing (13tu) was obtained after immunization of balb/c mice with heat-killed bacteria and was characterized by enzyme immunoassay and western blot analysis, by use of lps and proteinase k-treated bacterial lysates, analyses in which the antibody was shown to be highly specific for the homologous antigen. in ad ...199910325309
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