Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| implications of rrna operon copy number and ribosome content in the marine oligotrophic ultramicrobacterium sphingomonas sp. strain rb2256. | sphingomonas sp. strain rb2256 is a representative of the dominant class of ultramicrobacteria that are present in marine oligotrophic waters. in this study we examined the rrna copy number and ribosome content of rb2256 to identify factors that may be associated with the relatively low rate of growth exhibited by the organism. it was found that rb2256 contains a single copy of the rrna operon, in contrast to vibrio spp., which contain more than eight copies. the maximum number of ribosomes per ... | 1998 | 9797303 |
| accumulation of alpha-keto acids as essential components in cyanide assimilation by pseudomonas fluorescens ncimb 11764. | pyruvate (pyr) and alpha-ketoglutarate (alphakg) accumulated when cells of pseudomonas fluorescens ncimb 11764 were cultivated on growth-limiting amounts of ammonia or cyanide and were shown to be responsible for the nonenzymatic removal of cyanide from culture fluids as previously reported (j.-l. chen and d. a. kunz, fems microbiol. lett. 156:61-67, 1997). the accumulation of keto acids in the medium paralleled the increase in cyanide-removing activity, with maximal activity (760 micromol of cy ... | 1998 | 9797306 |
| a small, dilute-cytoplasm, high-affinity, novel bacterium isolated by extinction culture and having kinetic constants compatible with growth at ambient concentrations of dissolved nutrients in seawater. | dilutions of raw seawater produced a bacterial isolate capable of extended growth in unamended seawater. its 2.9-mb genome size and 40-fg dry mass were similar to values for many naturally occurring aquatic organotrophs, but water and dna comprised a large portion of this small chemoheterotroph, as compared to escherichia coli. the isolate used only a few aromatic hydrocarbons and acetate, and glucose and amino acid incorporation were entirely absent, although many membrane and cytoplasmic prote ... | 1998 | 9797308 |
| detection of ralstonia solanacearum, which causes brown rot of potato, by fluorescent in situ hybridization with 23s rrna-targeted probes. | during the past few years, ralstonia (pseudomonas) solanacearum race 3, biovar 2, was repeatedly found in potatoes in western europe. to detect this bacterium in potato tissue samples, we developed a method based on fluorescent in situ hybridization (fish). the nearly complete genes encoding 23s rrna of five r. solanacearum strains and one ralstonia pickettii strain were pcr amplified, sequenced, and analyzed by sequence alignment. this resulted in the construction of an unrooted tree and suppor ... | 1998 | 9797321 |
| genetic characterization of pepp, which encodes an aminopeptidase p whose deficiency does not affect lactococcus lactis growth in milk, unlike deficiency of the x-prolyl dipeptidyl aminopeptidase. | we sequenced the pepp gene of lactococcus lactis, which encodes an aminopeptidase p (pepp), and demonstrated that the x-prolyl dipeptidyl aminopeptidase pepx plays a more important role than pepp in nitrogen nutrition. pepp shares homology with methionine aminopeptidases and could play a role in the maturation of nascent proteins. | 1998 | 9797327 |
| a novel screening method for isolating exopolysaccharide-deficient mutants. | a screening method based on differential staining of the wild type and exopolysaccharide-deficient mutants of rhizobium (sinorhizobium) meliloti by the lipophilic dye sudan black b is described. mutants defective in the production of either succinoglycan or eps ii (galactoglucan) were isolated by using this method, which might also prove useful for isolating exopolysaccharide-defective derivatives of other bacteria. | 1998 | 9797329 |
| metal toxicity reduction in naphthalene biodegradation by use of metal-chelating adsorbents | a model system comprising microbial degradation of naphthalene in the presence of cadmium has been developed to evaluate metal toxicity associated with polyaromatic hydrocarbon biodegradation and its reduction by the use of unmodified and surfactant-modified clays in comparison with a commercially available chelating resin (chelex 100; bio-rad). the toxicity of cadmium associated with naphthalene biodegradation was shown to be reduced significantly by using the modified-clay complex and chelex r ... | 1998 | 9797332 |
| quantitative structure/activity relationship for the rate of conversion of c4-substituted catechols by catechol-1,2-dioxygenase from pseudomonas putida (arvilla) c1. | the influence of various c4/c5 substituents in catechol (1,2-dihydroxybenzene) derivatives on the overall rate of conversion by catechol-1,2-dioxygenase from pseudomonas putida (arvilla) c1 was investigated. using catechol, 4-methylcatechol, 4-fluorocatechol, 4-chlorocatechol, 4-bromocatechol, 4,5-difluorocatechol and 4-chloro-5-fluorocatechol, it could be demonstrated that substituents at the c4 and/or c5 position decrease the rate of conversion, from 62% (4-methylcatechol) down to 0.7% (4-chlo ... | 1998 | 9799107 |
| cloning and nucleotide sequence of amidase gene from pseudomonas putida. | amidases are a class of enzymes which convert amides to acids and have potential value in the development of commercial bioprocesses for the production of useful chemicals. a gene encoding an amidase in pseudomonas putida 5b has been cloned, sequenced, and overexpressed in escherichia coli. an additional open reading frame (p38k) encoding a putative protein of 38 kda was found immediately upstream of the amidase gene. this work continues our characterization of a p. putida operon, which now appe ... | 1998 | 9809753 |
| 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 ... | 1998 | 9811637 |
| 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 ... | 1998 | 9811638 |
| targeted mutagenesis of sigma54 activator proteins in myxococcus xanthus. | myxococcus xanthus dna segments related to the highly conserved central sequence of sigma54 activator proteins have been investigated. a genetic technique designed to inactivate a gene that encodes such an activator by inserting a plasmid-borne internal fragment of the putative gene has been tested. when the internal fragment inserted by homologous recombination into the corresponding chromosomal locus, the expected duplication of the gene was observed by southern hybridization. the single restr ... | 1998 | 9811647 |
| physical and genetic map of the pasteurella multocida a:1 chromosome. | a physical and genetic map of the pasteurella multocida a:1 genome was generated by using the restriction enzymes apai, ceui, and noti. the positions of 23 restriction sites and 32 genes, including 5 rrn operons, were localized on the 2.35-mbp single circular chromosome. this report presents the first genetic and physical map for this genus. | 1998 | 9811669 |
| synthesis of medium-chain-length polyhydroxyalkanoates in arabidopsis thaliana using intermediates of peroxisomal fatty acid beta-oxidation. | polyhydroxyalkanoate (pha) is a family of polymers composed primarily of r-3-hydroxyalkanoic acids. these polymers have properties of biodegradable thermoplastics and elastomers. medium-chain-length phas (mcl-phas) are synthesized in bacteria by using intermediates of the beta-oxidation of alkanoic acids. to assess the feasibility of producing mcl-phas in plants, arabidopsis thaliana was transformed with the phac1 synthase from pseudomonas aeruginosa modified for peroxisome targeting by addition ... | 1998 | 9811811 |
| 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 ... | 1998 | 9817894 |
| pseudomonas putida infections of the oyster toadfish (opsanus tau). | 1998 | 9818379 | |
| the transposable elements resident on the plasmids of pseudomonas putida strain h, tn5501 and tn5502, are cryptic transposons of the tn3 family. | genes for (methyl)phenol degradation in pseudomonas putida strain h (phl genes) are located on the plasmid ppgh1. adjacent to the phl catabolic operon we identified a cryptic transposon, tn5501, of the tn3 family (class ii transposons). the genes encoding the resolvase and the transposase are transcribed in the same direction, as is common for the tn501 subfamily. the enzymes encoded by tn5501, however, show only the overall homology characteristic for resolvases/integrases and transposases of t ... | 1998 | 9819061 |
| isopropylbenzene catabolic pathway in pseudomonas putida re204: nucleotide sequence analysis of the ipb operon and neighboring dna from pre4. | pseudomonas putida re204 employs a set of plasmid-specified enzymes in the catabolism of isopropylbenzene (cumene) and related alkylbenzenes. a 21,768 bp segment of the plasmid pre4, whose sequence is discussed here, includes the ipb (isopropylbenzene catabolic) operon as well as associated genetic elements. the ipb operon, ipbaaabacadbcegfhd, encodes enzymes catalyzing the conversion of isopropylbenzene to isobutyrate, pyruvate, and acetyl-coenzyme a as well as an outer membrane protein (ipbh) ... | 1998 | 9821257 |
| protein organization on the pha inclusion cytoplasmic boundary. | polyhydroxyalkanoate (pha) cellular inclusions consist of polyesters, phospholipids, and proteins. both the polymerase and the depolymerase enzymes are active components of the structure. recently, proteins associated with these inclusions have been described in a number of bacterial species. in order to further clarify the structure and function of these proteins in relation to polymer inclusions, ultrastructural studies of isolated polymer inclusions were initiated. the surface boundary charac ... | 1998 | 9821672 |
| investigation of the function of proteins associated to polyhydroxyalkanoate inclusions in pseudomonas putida bmo1. | polyhydroxyalkanoate (pha) granule associated proteins from pseudomonas oleovorans were purified and the n-terminal sequences of two major proteins migrating in sodium dodecyl sulfate polyacrylamide gels with a relative molecular mass of 18 and 43 kda (ga1 and ga2, respectively) were analyzed. radiolabeled degenerate probes deduced from these amino acid sequences were used to identify genomic dna fragments from p. oleovorans and pseudomonas putida encoding ga1 and ga2. dna sequence analysis of t ... | 1998 | 9821673 |
| formation of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) by pha synthase from ralstonia eutropha. | the acetoacetyl-coa reductase and the polyhydroxyalkanoate (pha) synthase from ralstonia eutropha (formerly alcaligenes eutrophus) were expressed in escherichia coli, klebsiella aerogenes, and pha-negative mutants of r. eutropha and pseudomonas putida. while expression in e. coli strains resulted in the accumulation of poly(3-hydroxybutyrate) [phb], strains of r. eutropha, p. putida and k. aerogenes accumulated poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [poly(3hb-co-3hhx)] when even chain fat ... | 1998 | 9821674 |
| the type iv leader peptidase/n-methyltransferase of vibrio vulnificus controls factors required for adherence to hep-2 cells and virulence in iron-overloaded mice. | vibrio vulnificus expresses a number of potential virulence determinants that may contribute to its ability to cause a severe and rapidly disseminating septicemia in susceptible hosts. we have cloned and characterized two genes encoding products related to components of the type iv pilus biogenesis and general secretory (type ii) pathways by complementation of a type iv peptidase/n-methyltransferase (pild) mutant of pseudomonas aeruginosa with a v. vulnificus genomic library. one of the genes (v ... | 1998 | 9826339 |
| complete dna sequence and detailed analysis of the yersinia pestis kim5 plasmid encoding murine toxin and capsular antigen. | yersinia pestis, the causative agent of plague, harbors at least three plasmids necessary for full virulence of the organism, two of which are species specific. one of the y. pestis-specific plasmids, pmt1, is thought to promote deep tissue invasion, resulting in more acute onset of symptoms and death. we determined the entire nucleotide sequence of y. pestis kim5 pmt1 and identified potential open reading frames (orfs) encoded by the 100,990-bp molecule. based on codon usage for known yersinial ... | 1998 | 9826348 |
| isolation and transposon mutagenesis of a pseudomonas putida kt2442 toluene-resistant variant: involvement of an efflux system in solvent resistance. | a toluene-resistant variant of pseudomonas putida kt2442, strain tol, was isolated after liquid cultivation under xylene followed by toluene for 1 month in each condition. almost all the populations of the variant strain formed small but readily visible colonies under toluene within 24 h at 30 degrees c. the toluene-resistant strain also showed an increase in resistance to some unrelated antibiotics. several toluene-sensitive tn5 mutants have been isolated from the toluene-resistant strain and s ... | 1998 | 9827328 |
| mutational analysis of the rhizobium etli reca operator. | based upon our earlier studies (a. tapias, a. r. fernández de henestrosa, and j. barbé, j. bacteriol. 179:1573-1579, 1997) we hypothesized that the regulatory sequence of the rhizobium etli reca gene was ttgn11caa. however, further detailed analysis of the r. etli reca operator described in the present work suggests that it may in fact be gaacn7gtac. this new conclusion is based upon pcr mutagenesis analysis carried out in the r. etli reca operator, which indicates that the gaac and gtac submoti ... | 1998 | 9829943 |
| 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 ... | 1998 | 9829947 |
| neonatal pseudomonas putida infection presenting as staphylococcal scalded skin syndrome. | a case of neonatal pseudomonas putida sepsis presenting as staphylococcal scalded skin syndrome is described. staphylococcal scalded skin syndrome is a clinical term used for a spectrum of primarily neonatal blistering skin disorders caused by the exfoliative toxins of staphylococcus aureus. the disease typically begins with general erythema and fever, followed by the formation of large fluid-filled bullae that coalesce and rupture on slightest pressure to leave extensive areas of denuded skin. ... | 1998 | 9832266 |
| expression of the pseudomonas aeruginosa gentamicin resistance gene aacc3 in escherichia coli. | the pseudomonas aeruginosa aacc3 gene was expressed in escherichia coli after cloning of the single gene behind the strong tac promoter. in the original pseudomonas strain, aacc3 is preceded by cysc; together they form a single transcription unit. the ribosome-binding site and start codon of aacc3 are involved in a putative intercistronic hairpin, the stability of which interfered with the aminoglycoside resistance level. in northern blots, full-length transcripts comprising both cysc and aacc3 ... | 1998 | 9835511 |
| degradation of polychlorinated biphenyl metabolites by naphthalene-catabolizing enzymes. | the ability of the dehydrogenase and ring cleavage dioxygenase of the naphthalene degradation pathway to transform 3,4-dihydroxylated biphenyl metabolites was investigated. 1,2-dihydro-1, 2-dihydroxynaphthalene dehydrogenase was expressed as a histidine-tagged protein. the purified enzyme transformed 2, 3-dihydro-2,3-dihydroxybiphenyl, 3,4-dihydro-3,4-dihydroxybiphenyl, and 3,4-dihydro-3,4-dihydroxy-2,2',5,5'-tetrachlorobiphenyl to 2, 3-dihydroxybiphenyl, 3,4-dihydroxybiphenyl (3,4-dhb), and 3, ... | 1998 | 9835542 |
| use of 13c nuclear magnetic resonance and gas chromatography to examine methionine catabolism by lactococci. | formation of methanethiol from methionine is widely believed to play a significant role in development of cheddar cheese flavor. however, the catabolism of methionine by cheese-related microorganisms has not been well characterized. two independent methionine catabolic pathways are believed to be present in lactococci, one initiated by a lyase and the other initiated by an aminotransferase. to differentiate between these two pathways and to determine the possible distribution between the pathway ... | 1998 | 9835547 |
| cloning and characterization of nadp-mannitol dehydrogenase cdna from the button mushroom, agaricus bisporus, and its expression in response to nacl stress. | mannitol, a six-carbon sugar alcohol, is the main storage carbon in the button mushroom, agaricus bisporus. given the physiological importance of mannitol metabolism in growth, fruit body development, and salt tolerance of a. bisporus, the enzyme responsible for mannitol biosynthesis, nadp-dependent mannitol dehydrogenase (mtdh) (ec 1.1.1.138), was purified to homogeneity, and mtdh cdna was cloned, sequenced, and characterized. to our knowledge, this represents the first report on the isolation ... | 1998 | 9835550 |
| isolation of marine polycyclic aromatic hydrocarbon (pah)-degrading cycloclasticus strains from the gulf of mexico and comparison of their pah degradation ability with that of puget sound cycloclasticus strains. | phenanthrene- and naphthalene-degrading bacteria were isolated from four offshore and nearshore locations in the gulf of mexico by using a modified most-probable-number technique. the concentrations of these bacteria ranged from 10(2) to 10(6) cells per ml of wet surficial sediment in mildly contaminated and noncontaminated sediments. a total of 23 strains of polycyclic aromatic hydrocarbon (pah)-degrading bacteria were obtained. based on partial 16s ribosomal dna sequences and phenotypic charac ... | 1998 | 9835552 |
| purification and characterization of gallic acid decarboxylase from pantoea agglomerans t71 | oxygen-sensitive gallic acid decarboxylase from pantoea (formerly enterobacter) agglomerans t71 was purified from a cell extract after stabilization by reducing agents. this enzyme has a molecular mass of approximately 320 kda and consists of six identical subunits. it is highly specific for gallic acid. gallic acid decarboxylase is unique among similar decarboxylases in that it requires iron as a cofactor, as shown by plasma emission spectroscopy (which revealed an iron content of 0.8 mol per m ... | 1998 | 9835557 |
| a technique to quantify the population size and composition of the biofilm component in communities of bacteria in the phyllosphere | the presence of microbial biofilms in the phyllosphere of terrestrial plants has recently been demonstrated, but few techniques to study biofilms associated with living plant tissues are available. here we report a technique to estimate the proportion of the bacterial population on leaves that is assembled in biofilms and to quantitatively isolate bacteria from the biofilm and nonbiofilm (solitary) components of phyllosphere microbial communities. this technique is based on removal of bacteria f ... | 1998 | 9835563 |
| psychrotolerant bacteria isolated from arctic soil that degrade polychlorinated biphenyls at low temperatures | psychrotolerant polychlorinated biphenyl (pcb)-degrading bacteria were isolated at 7 degreesc from pcb-contaminated arctic soil by using biphenyl as the sole organic carbon source. these isolates were distinguished from each other by differences in substrates that supported growth and substrates that were oxidized. 16s ribosomal dna sequences suggest that these isolates are most closely related to the genus pseudomonas. total removal of aroclor 1242, and rates of removal of selected pcb congener ... | 1998 | 9835569 |
| enumeration and detection of anaerobic ferrous iron-oxidizing, nitrate-reducing bacteria from diverse european sediments. | anaerobic, nitrate-dependent microbial oxidation of ferrous iron was recently recognized as a new type of metabolism. in order to study the occurrence of three novel groups of ferrous iron-oxidizing, nitrate-reducing bacteria (represented by strains brg1, brg2, and brg3), 16s rrna-targeted oligonucleotide probes were developed. in pure-culture experiments, these probes were shown to be suitable for fluorescent in situ hybridization, as well as for hybridization analysis of denaturing gradient ge ... | 1998 | 9835573 |
| assessment of changes in microbial community structure during operation of an ammonia biofilter with molecular tools. | biofiltration has been used for two decades to remove odors and various volatile organic and inorganic compounds in contaminated off-gas streams. although biofiltration is widely practiced, there have been few studies of the bacteria responsible for the removal of air contaminants in biofilters. in this study, molecular techniques were used to identify bacteria in a laboratory-scale ammonia biofilter. both 16s rrna and ammonia monooxygenase (amoa) genes were used to characterize the heterotrophi ... | 1998 | 9835577 |
| characterization of cell lysis in pseudomonas putida induced upon expression of heterologous killing genes. | active biological containment systems are based on the controlled expression of killing genes. these systems are of interest for the pseudomonadaceae because of the potential applications of these microbes as bioremediation agents and biopesticides. the physiological effects that lead to cell death upon the induction of expression of two different heterologous killing genes in nonpathogenic pseudomonas putida kt2440 derivatives have been analyzed. p. putida cmc4 and cmc12 carry in their chromoso ... | 1998 | 9835581 |
| metabolism of benzene, toluene, and xylene hydrocarbons in soil | enrichment cultures obtained from soil exposed to benzene, toluene, and xylene (btx) mineralized benzene and toluene but cometabolized only xylene isomers, forming polymeric residues. this observation prompted us to investigate the metabolism of 14c-labeled btx hydrocarbons in soil, either individually or as mixtures. btx-supplemented soil was incubated aerobically for up to 4 weeks in a sealed system that automatically replenished any o2 consumed. the decrease in solvent vapors and the producti ... | 1998 | 9835584 |
| detection and isolation of novel rhizopine-catabolizing bacteria from the environment | microbial rhizopine-catabolizing (moc) activity was detected in serial dilutions of soil and rhizosphere washes. the activity observed generally ranged between 10(6) and 10(7) catabolic units per g, and the numbers of nonspecific culture-forming units were found to be approximately 10 times higher. a diverse set of 37 isolates was obtained by enrichment on scyllo-inosamine-containing media. however, none of the bacteria that were isolated were found to contain dna sequences homologous to the kno ... | 1998 | 9835587 |
| an immunological strategy to monitor in situ the phosphate starvation state in thiobacillus ferrooxidans | thiobacillus ferrooxidans is one of the chemolithoautotrophic bacteria important in industrial biomining operations. during the process of ore bioleaching, the microorganisms are subjected to several stressing conditions, including the lack of some essential nutrients, which can affect the rates and yields of bioleaching. when t. ferrooxidans is starved for phosphate, the cells respond by inducing the synthesis of several proteins, some of which are outer membrane proteins of high molecular weig ... | 1998 | 9835593 |
| species-specific oligonucleotides for enumeration of pseudomonas putida f1, burkholderia sp. strain js150, and bacillus subtilis atcc 7003 in biodegradation experiments. | species-specific sequences were identified within the v4 variable region of 16s rrna of two bacterial species capable of aromatic hydrocarbon metabolism, pseudomonas putida f1 and burkholderia sp. strain js150, and a third, bacillus subtilis atcc 7003, that can function as a secondary degrader. fluorescent in situ hybridization (fish) with species-specific oligonucleotides was used for direct counting of these species throughout a phenol biodegradation experiment in batch culture. traditional di ... | 1998 | 9835594 |
| recombinant klebsiella oxytoca strains with improved efficiency in removal of high nitrate loads | klebsiella oxytoca cect 4460 removes high nitrate loads from industrial wastewaters without accumulation of nitrite under optimal culture conditions; however, under nonoptimal conditions nitrite accumulates. this situation reflects an in vivo-limited functioning of nitrite reductase in this strain. as a way to overcome this limitation, an increase in the nitrite reductase gene dose in k. oxytoca cect 4460 was considered. to achieve this, we cloned and transferred into this strain the klebsiella ... | 1998 | 9835599 |
| construction of a bioluminescent reporter strain to detect polychlorinated biphenyls | a bioluminescent reporter strain, ralstonia eutropha env307(putk60), was constructed for the detection of polychlorinated biphenyls by inserting the biphenyl promoter upstream of the bioluminescence genes. in the presence of a nonionic surfactant, which enhances the solubility of chlorinated biphenyls, bioluminescence was induced three- to fourfold over background by biphenyl, monochlorinated biphenyls, and aroclor 1242. the minimum detection limits for these compounds ranged from 0.15 mg/liter ... | 1998 | 9835601 |
| induction of the tod operon by trichloroethylene in pseudomonas putida tva8. | bioluminescence, mrna levels, and toluene degradation rates in pseudomonas putida tva8 were measured as a function of various concentrations of toluene and trichloroethylene (tce). tva8 showed an increasing bioluminescence response to increasing tce and toluene concentrations. compared to uninduced tva8 cultures, todc1 mrna levels increased 11-fold for tce-treated cultures and 13-fold for toluene-treated cultures. compared to uninduced p. putida f1 cultures, todc1 mrna levels increased 4.4-fold ... | 1998 | 9835608 |
| simultaneous degradation of chloro- and methyl-substituted aromatic compounds: competition between pseudomonas strains using the ortho and meta pathway or the ortho pathway exclusively. | pseudomonas sp. d7-4 and pseudomonas sp. b13 fr1(pfrc20p) degraded mixtures of chloro- and methyl-substituted benzoates exclusively via an extended ortho pathway, whereas in pseudomonas putida wr 201 both ortho and meta fission were induced by mixtures of 3-chloro- and 3-methylbenzoate or even by 3-chloro-benzoate alone. the competition behaviour of these strains was compared in batch and in chemostat cultures.. despite misrouting of metabolites, strain wr201 was competitive, in a lot of the com ... | 1998 | 9840960 |
| phosphate starvation-independent 2-aminoethylphosphonic acid biodegradation in a newly isolated strain of pseudomonas putida, ng2. | a strain of pseudomonas putida that utilized the biogenic organophosphonate 2-aminoethylphosphonic acid as sole carbon and energy, nitrogen and phosphorus source contained 2-aminoethylphosphonic acid: pyruvate aminotransferase and phosphonoacetaldehyde hydrolase (phosphonatase) activities which were inducible by the presence of 2-aminoethylphosphonic acid in the culture medium, regardless of the phosphate status of the cells. neither of these activities were induced in their phosphate-free or ph ... | 1998 | 9841125 |
| molecular genetics of the genus paracoccus: metabolically versatile bacteria with bioenergetic flexibility. | paracoccus denitrificans and its near relative paracoccus versutus (formerly known as thiobacilllus versutus) have been attracting increasing attention because the aerobic respiratory system of p. denitrificans has long been regarded as a model for that of the mitochondrion, with which there are many components (e.g., cytochrome aa3 oxidase) in common. members of the genus exhibit a great range of metabolic flexibility, particularly with respect to processes involving respiration. prominent exam ... | 1998 | 9841665 |
| the virulence plasmid of yersinia, an antihost genome. | the 70-kb virulence plasmid enables yersinia spp. (yersinia pestis, y. pseudotuberculosis, and y. enterocolitica) to survive and multiply in the lymphoid tissues of their host. it encodes the yop virulon, an integrated system allowing extracellular bacteria to disarm the cells involved in the immune response, to disrupt their communications, or even to induce their apoptosis by the injection of bacterial effector proteins. this system consists of the yop proteins and their dedicated type iii sec ... | 1998 | 9841674 |
| bacterial iron transport: 1h nmr determination of the three-dimensional structure of the gallium complex of pyoverdin g4r, the peptidic siderophore of pseudomonas putida g4r. | among the fluorescent pseudomonas species, pseudomonas putida is a rare case of a nitrogen-fixing bacterium that transforms nitrogen into ammonia. when grown under iron-deficient conditions, it produces two major pyoverdins: pyoverdin g4r and pyoverdin g4ra. their primary structures have been established using fab-ms and one- and two-dimensional 15n, 13c, and 1h nmr on both the unlabeled and 15n-labeled compounds [salah el din, a. l. m., et al. (1997) tetrahedron 53, 12539-12552]. the two pyover ... | 1998 | 9843403 |
| siderotyping of fluorescent pseudomonads: characterization of pyoverdines of pseudomonas fluorescens and pseudomonas putida strains from antarctica. | five independent fluorescent pseudomonad isolates originating from antarctica were analysed for their pyoverdine systems. a pyoverdine-related siderotyping, which involved pyoverdine-induced growth stimulation, pyoverdine-mediated iron uptake, pyoverdine analysis by electrophoresis and isoelectric focusing, revealed three different pyoverdine-related siderotypes among the five isolates. one siderotype, including pseudomonas fluorescens 1w and p. fluorescens 10cw, was identical to that of p. fluo ... | 1998 | 9846748 |
| malonate decarboxylase of pseudomonas putida is composed of five subunits. | two different forms of malonate decarboxylase were purified from pseudomonas putida. the active form was composed of the five different subunits alpha (60 kda), beta (33 kda), gamma (28 kda), delta (13 kda), and epsilon (30 kda) and the inactive form was composed of the four subunits lacking the epsilon subunit. the former catalyzed the decarboxylation of malonate to acetate, but the latter could not, although it retained both activities of acetyl-coa:malonate coa transferase and malonyl-coa dec ... | 1998 | 9851033 |
| cloning and molecular analysis of the poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyalkanoate) biosynthesis genes in pseudomonas sp. strain 61-3. | two types of polyhydroxyalkanoate (pha) biosynthesis gene loci (phb and pha) of pseudomonas sp. strain 61-3, which produces a blend of poly(3-hydroxybutyrate) [p(3hb)] homopolymer and a random copolymer (poly(3-hydroxybutyrate-co-3-hydroxyalkanoate) [p(3hb-co-3ha]) consisting of 3ha units of 4 to 12 carbon atoms, were cloned and analyzed at the molecular level. in the phb locus, three open reading frames encoding polyhydroxybutyrate (phb) synthase (phbcps), beta-ketothiolase (phbaps), and nadph- ... | 1998 | 9851987 |
| 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. ... | 1998 | 9851995 |
| incp plasmids are unusually effective in mediating conjugation of escherichia coli and saccharomyces cerevisiae: involvement of the tra2 mating system. | mobilizable shuttle plasmids containing the origin-of-transfer (orit) region of plasmids f (incfi), colib-p9 (inci1), and rp4/rp1 (incpalpha) were constructed to test the ability of the cognate conjugation system to mediate gene transfer from escherichia coli to saccharomyces cerevisiae. only the palpha system caused detectable mobilization to yeast, giving peak values of 5 x 10(-5) transconjugants per recipient cell in 30 min. transfer of the shuttle plasmid required carriage of orit in cis and ... | 1998 | 9851996 |
| sequence diversity of the opri gene, coding for major outer membrane lipoprotein i, among rrna group i pseudomonads. | the sequence of opri, the gene coding for the major outer membrane lipoprotein i, was determined by pcr sequencing for representatives of 17 species of rrna group i pseudomonads, with a special emphasis on pseudomonas aeruginosa and pseudomonas fluorescens. within the p. aeruginosa species, opri sequences for 25 independent isolates were found to be identical, except for one silent substitution at position 96. the opri sequences diverged more for the other rrna group i pseudomonads (85 to 91% si ... | 1998 | 9851998 |
| the modified beta-ketoadipate pathway in rhodococcus rhodochrous n75: enzymology of 3-methylmuconolactone metabolism. | rhodococcus rhodochrous n75 is able to metabolize 4-methylcatechol via a modified beta-ketoadipate pathway. this organism has been shown to activate 3-methylmuconolactone by the addition of coenzyme a (coa) prior to hydrolysis of the butenolide ring. a lactone-coa synthetase is induced by growth of r. rhodochrous n75 on p-toluate as a sole source of carbon. the enzyme has been purified 221-fold by ammonium sulfate fractionation, hydrophobic chromatography, gel filtration, and anion-exchange chro ... | 1998 | 9852013 |
| 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 ... | 1998 | 9852014 |
| active efflux of organic solvents by pseudomonas putida s12 is induced by solvents. | induction of the membrane-associated organic solvent efflux system srpabc of pseudomonas putida s12 was examined by cloning a 312-bp dna fragment, containing the srp promoter, in the broad-host-range reporter vector pkrz-1. compounds that are capable of inducing expression of the srpabc genes include aromatic and aliphatic solvents and alcohols. general stress conditions such as ph, temperature, nacl, or the presence of organic acids did not induce srp transcription. although the solvent efflux ... | 1998 | 9852029 |
| transcriptional activation of the catechol and chlorocatechol operons: variations on a theme. | the ortho-cleavage pathways of catechol and 3-chlorocatechol are central catabolic pathways of pseudomonas putida that convert aromatic and chloroaromatic compounds to tricarboxylic acid (tca)-cycle intermediates. they are encoded by the evolutionarily related catbca and clcabd operons, respectively. expression of the cat and clc operons requires the lysr-type transcriptional activators catr and clcr, and the inducer molecules cis,cis-muconate and 2-chloro-cis,cis-muconate. in addition to sequen ... | 1998 | 9858745 |
| protein binding in vivo to op2 promoter of the pseudomonas putida tol plasmid. | the transcription of op2 encoding enzymes for m-toluate catabolism on the pseudomonas putida tol plasmid is activated by basal-level xyls protein in the presence of m-toluate or by overproduced xyls protein in the absence of m-toluate. in this study, in vivo dimethyl sulfate (dms) footprinting was performed to understand the mechanism of transcriptional regulation of op2 promoter by xyls. in the presence of overproduced xyls without m-toluate, several protected nucleotides were observed, indicat ... | 1998 | 9861447 |
| 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 ... | 1999 | 9864312 |
| identification of an escherichia coli pepa homolog and its involvement in suppression of the algb phenotype in mucoid pseudomonas aeruginosa. | strains of pseudomonas aeruginosa isolated from the respiratory tracts of patients with cystic fibrosis often display a mucoid morphology due to high levels of expression of the exopolysaccharide alginate. the response regulator algb is required for full transcription of the alginate biosynthetic operon. repeated attempts to demonstrate a direct interaction between algb and the promoter region of algd, the first gene in the alginate operon, have thus far been unsuccessful. the possibility that a ... | 1999 | 9864319 |
| adaptation of mycobacterium smegmatis to stationary phase. | mycobacterium tuberculosis can persist for many years within host lung tissue without causing clinical disease. little is known about the state in which the bacilli survive, although it is frequently referred to as dormancy. some evidence suggests that cells survive in nutrient-deprived stationary phase. therefore, we are studying stationary-phase survival of mycobacterium smegmatis as a model for mycobacterial persistence. m. smegmatis cultures could survive 650 days of either carbon, nitrogen, ... | 1999 | 9864340 |
| genetic and biochemical analyses of the tec operon suggest a route for evolution of chlorobenzene degradation genes. | the teca broad-spectrum chlorobenzene dioxygenase of burkholderia sp. strain ps12 catalyzes the first step in the mineralization of 1,2,4, 5-tetrachlorobenzene. the catabolic genes were localized on a small plasmid that belongs to the incpbeta incompatibility group. pcr analysis of the genetic environment of the tec genes indicated high similarity to the transposon-organized catabolic tcb chlorobenzene degradation genes of pseudomonas sp. strain p51. sequence analysis of the regions flanking the ... | 1999 | 9864349 |
| short-run tests for determining harmful effects of pcb-containing engine oils on cells. | our main objective was to set up reproducible methods for a rapid determination of harmful effects of pcb-containing engine oils on cells. we used a plate method and scenedesmus quadricauda, saccharomyces cerevisiae, rhodotorula glutinis and pseudomonas putida as test organisms. | 1998 | 9867477 |
| isolation and characterization of toluene-sensitive mutants from pseudomonas putida ih-2000. | two toluene-sensitive mutants were generated from pseudomonas putida ih-2000, the first known toluene-tolerant isolate, by tn5 transposon mutagenesis. these mutants were unable to grow in the presence of toluene (log p(ow) 2.8) but they could grow in medium overlaid with organic solvents having a log p(ow) value higher than that of toluene such as p-xylene (log p(ow) 3.1), cyclohexane (log p(ow) 3.4) and n-hexane (log p(ow) 3.9). the tn5 transposable element knocked out a cyob-like gene in one m ... | 1998 | 9868765 |
| type ii topoisomerase mutations in ciprofloxacin-resistant strains of pseudomonas aeruginosa. | we determined the sequences of the quinolone resistance-determining regions of gyra, gyrb, and parc genes for 30 clinical strains of pseudomonas aeruginosa resistant to ciprofloxacin that were previously complemented by wild-type gyra and gyrb plasmid-borne alleles and studied for their coresistance to imipenem (e. cambau, e. perani, c. dib, c. petinon, j. trias, and v. jarlier, antimicrob. agents chemother. 39:2248-2252, 1995). in the present study, we found mutations in type ii topoisomerase g ... | 1999 | 9869566 |
| effect of oxidative stress on the biosynthesis of 2-c-methyl-d-erythritol-2,4-cyclopyrophosphate and isoprenoids by several bacterial strains. | in this study, the gram-negative bacteria xanthomonas campestris, xanthomonas maltophilia, and pseudomonas putida, facultative parasites of plants and animals, were shown to accumulate 2-c-methyl-d-erythritol-2,4-cyclopyrophosphate (mec) in response to benzyl-viologen-induced oxidative stress. corynebacterium ammoniagenes mutants capable of accumulating mec in the absence of an exogenous oxidative stress inducer were obtained. isoprenoid synthesis and mec synthesis in these and other bacteria we ... | 1998 | 9871022 |
| a mechanism of resistance to hydrogen peroxide in vibrio rumoiensis s-1. | a possible mechanism of resistance to hydrogen peroxide (h2o2) in vibrio rumoiensis, isolated from the h2o2-rich drain pool of a fish processing plant, was examined. when v. rumoiensis cells were inoculated into medium containing either 5 mm or no h2o2, they grew in similar manners. a spontaneous mutant strain, s-4, derived from v. rumoiensis and lacking catalase activity did not grow at all in the presence of 5 mm h2o2. these results suggest that catalase is inevitably involved in the resistanc ... | 1999 | 9872762 |
| 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 ... | 1999 | 9872763 |
| thermal gradient gel electrophoresis analysis of bioprotection from pollutant shocks in the activated sludge microbial community. | we used a culture-independent approach, namely, thermal gradient gel electrophoresis (tgge) analysis of ribosomal sequences amplified directly from community dna, to determine changes in the structure of the microbial community following phenol shocks in the highly complex activated sludge ecosystem. parallel experimental model sewage plants were given shock loads of chlorinated and methylated phenols and simultaneously were inoculated (i) with a genetically engineered microorganism (gem) able t ... | 1999 | 9872766 |
| degradation of 3-chlorobenzoate under low-oxygen conditions in pure and mixed cultures of the anoxygenic photoheterotroph rhodopseudomonas palustris dcp3 and an aerobic alcaligenes species. | the presence or absence of molecular oxygen has been shown to play a crucial role in the degradability of haloaromatic compounds. in the present study, it was shown that anaerobic phototrophic 3-chlorobenzoate (3cba) metabolism by rhodopseudomonas palustris dcp3 is oxygen tolerant up to a concentration of 3 microm o2. simultaneous oxidation of an additional carbon source permitted light-dependent anaerobic 3cba degradation at oxygen input levels which, in the absence of such an additional compou ... | 1999 | 9872770 |
| polycyclic aromatic hydrocarbon degradation by a new marine bacterium, neptunomonas naphthovorans gen. nov., sp. nov. | two strains of bacteria were isolated from creosote-contaminated puget sound sediment based on their ability to utilize naphthalene as a sole carbon and energy source. when incubated with a polycyclic aromatic hydrocarbon (pah) compound in artificial seawater, each strain also degraded 2-methylnaphthalene and 1-methylnaphthalene; in addition, one strain, nag-2n-113, degraded 2,6-dimethylnaphthalene and phenanthrene. acenaphthene was not degraded when it was used as a sole carbon source but was d ... | 1999 | 9872786 |
| organic solvent tolerance of escherichia coli is independent of ompf levels in the membrane. | the organic solvent tolerance of escherichia coli was measured under conditions in which ompf levels were controlled by various means as follows: alteration of nacl concentration in the medium, transformation with a stress-responsive gene (mara, roba, or soxs), or disruption of the ompf gene. it was shown that solvent tolerance of e. coli did not depend upon ompf levels in the membrane. | 1999 | 9872794 |
| 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. | 1999 | 9872799 |
| antiseptics and disinfectants: activity, action, and resistance. | antiseptics and disinfectants are extensively used in hospitals and other health care settings for a variety of topical and hard-surface applications. a wide variety of active chemical agents (biocides) are found in these products, many of which have been used for hundreds of years, including alcohols, phenols, iodine, and chlorine. most of these active agents demonstrate broad-spectrum antimicrobial activity; however, little is known about the mode of action of these agents in comparison to ant ... | 1999 | 9880479 |
| assembly of xcpr in the cytoplasmic membrane is required for extracellular protein secretion in pseudomonas aeruginosa. | a broad range of extracellular proteins secreted by pseudomonas aeruginosa use the type ii or general secretory pathway (gsp) to reach the medium. this pathway requires the expression of at least 12 xcp gene products. xcpr, a putative nucleotide-binding protein, is essential for the secretion process across the outer membrane even though the protein contains no hydrophobic sequence that could target or anchor it to the bacterial envelope. for a better understanding of the relationship between xc ... | 1999 | 9882649 |
| 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 ... | 1999 | 9882667 |
| polyhydroxyalkanoate inclusion body-associated proteins and coding region in bacillus megaterium. | polyhydroxyalkanoic acids (pha) are carbon and energy storage polymers that accumulate in inclusion bodies in many bacteria and archaea in response to environmental conditions. this work presents the results of a study of pha inclusion body-associated proteins and an analysis of their coding region in bacillus megaterium 11561. a 7, 917-bp fragment of dna was cloned and shown to carry a 4,104-bp cluster of 5 pha genes, phap, -q, -r, -b, and -c. the phap and -q genes were shown to be transcribed ... | 1999 | 9882674 |
| molecular organization of the xcp gene cluster in pseudomonas putida: absence of an xcpx (gspk) homologue. | a dna fragment containing xcp (gsp) gene homologues, required for extracellular protein secretion by the general secretory pathway (gsp) in various gram-negative bacteria, was cloned from pseudomonas putida (pp) strain wcs358 and sequenced. the results presented here and those previously reported (de groot, a., krijger, j.-j., filloux, a., tommassen, j., 1996. characterization of type ii protein secretion (xcp) genes in the plant growth-stimulating pseudomonas putida, strain wcs358 mol. gen. gen ... | 1999 | 9889311 |
| 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 ... | 1999 | 9914303 |
| [occurrence of gram-negative non-fermenting rods in hemocultures and their sensitivity to antimicrobial agents]. | in the period from january 1993 to june 1996 were at the department of microbiology of the university hospital in olomouc 122 strains of gram-negative nonfermentative rod-shaped bacteria isolated from haemocultures. the majority represented the group of 51 strains of the genus acinetobacter (41.8%), complex a. calcoaceticus-baumannii (acb complex). the second largest group were 21 strains (17.2%) of pseudomonas aeruginosa. these were followed by 17 strains (13.9%) of stenotrophomonas maltophilia ... | 1998 | 9919762 |
| thermoregulated expression and characterization of an nad(p)h-dependent 2-cyclohexen-1-one reductase in the plant pathogenic bacterium pseudomonas syringae pv. glycinea. | the phytopathogenic bacterium pseudomonas syringae pv. glycinea pg4180.n9 causes bacterial blight of soybeans and preferably infects its host plant during periods of cold, humid weather conditions. to identify proteins differentially expressed at low temperatures, total cellular protein fractions derived from pg4180.n9 grown at 18 and 28 degreesc were separated by two-dimensional gel electrophoresis. of several proteins which appeared to be preferentially present at 18 degreesc, a 40-kda protein ... | 1999 | 9922244 |
| phaf, a polyhydroxyalkanoate-granule-associated protein of pseudomonas oleovorans gpo1 involved in the regulatory expression system for pha genes. | the phac1 gene codes for the medium-chain-length polyhydroxyalkanoate (mcl pha) synthase of pseudomonas oleovorans gpo1, which produces mcl pha when grown in an excess of carbon source and under nitrogen limitation. in this work, we have demonstrated, by constructing a recombinant p. oleovorans strain carrying a phac1::lacz reporter system, that the phac1 gene is expressed efficiently in the presence of octanoic acid while its expression is repressed when glucose or citrate is used as the carbon ... | 1999 | 9922249 |
| biochemical and genetic evidence for meta-ring cleavage of 2,4, 5-trihydroxytoluene in burkholderia sp. strain dnt. | 2,4,5-trihydroxytoluene (tht) oxygenase from burkholderia sp. strain dnt catalyzes the conversion of tht to an unstable ring fission product. biochemical and genetic studies of tht oxygenase were undertaken to elucidate the mechanism of the ring fission reaction. the tht oxygenase gene (dntd) was previously localized to the 1.2-kb dna insert subcloned in the recombinant plasmid designated pjs76 (w. c. suen and j. c. spain, j. bacteriol. 175:1831-1837, 1993). analysis of the deduced amino acid se ... | 1999 | 9922262 |
| cell density-dependent starvation survival of rhizobium leguminosarum bv. phaseoli: identification of the role of an n-acyl homoserine lactone in adaptation to stationary-phase survival. | the cell density dependence of stationary-phase survival of rhizobium leguminosarum has been investigated. following starvation by exhaustion of carbon or nitrogen, but not of phosphorus, the survival of cultures was dependent on the cell density at entry into stationary phase. high-density cultures survived with little or no loss of viability over a 20-day period in stationary phase. in contrast, low-density cultures lost viability rapidly but consisted of a heterogeneous population, a small fr ... | 1999 | 9922264 |
| interplay between chromosomal beta-lactamase and the mexab-oprm efflux system in intrinsic resistance to beta-lactams in pseudomonas aeruginosa. | we investigated the role of chromosomal beta-lactamase and the mexab-oprm efflux system in intrinsic resistance to beta-lactams in pseudomonas aeruginosa. determination of the susceptibilities of a series of isogenic mutants with impaired production of the beta-lactamase and the efflux system to 16 beta-lactams including penicillins, cephems, oxacephems, carbapenems, and a monobactam demonstrated that the intrinsic resistance of p. aeruginosa to most of the beta-lactams is due to the interplay o ... | 1999 | 9925544 |
| screening, nucleotide sequence, and biochemical characterization of an esterase from pseudomonas fluorescens with high activity towards lactones. | a genomic library of pseudomonas fluorescens dsm 50106 in a lambdaresiii phage vector was screened in escherichia coli k-12 for esterase activity by using alpha-naphthyl acetate and fast blue rr. a 3.2-kb dna fragment was subcloned from an esterase-positive clone and completely sequenced. esterase estf1 was encoded by a 999-bp open reading frame (orf) and exhibited significant amino acid sequence identity with members of the serine hydrolase family. the deduced amino acid sequences of two other ... | 1999 | 9925571 |
| production of medium-chain-length poly(3-hydroxyalkanoates) from gluconate by recombinant escherichia coli. | it was shown recently that recombinant escherichia coli, defective in the beta-oxidation cycle and harboring a medium-chain-length (mcl) poly(3-hydroxyalkanoate) (pha) polymerase-encoding gene of pseudomonas, is able to produce mcl pha from fatty acids but not from sugars or gluconate (s. langenbach, b. h. a. rehm, and a. steinbüchel, fems microbiol. lett. 150:303-309, 1997; q. ren, ph.d. thesis, eth zürich, zürich, switzerland, 1997). in this study, we report the formation of mcl pha from gluco ... | 1999 | 9925580 |
| isolation and characterization of a mycobacterium species capable of degrading three- and four-ring aromatic and aliphatic hydrocarbons. | mycobacterium sp. strain ch1 was isolated from polycyclic aromatic hydrocarbon (pah)-contaminated freshwater sediments and identified by analysis of 16s rdna sequences. strain ch1 was capable of mineralizing three- and four-ring pahs including phenanthrene, pyrene, and fluoranthene. in addition, strain ch1 could utilize phenanthrene or pyrene as a sole carbon and energy source. a lag phase of at least 3 days was observed during pyrene mineralization. this lag phase decreased to less than 1 day w ... | 1999 | 9925581 |
| purification and characterization of a novel 5-oxoprolinase (without atp-hydrolyzing activity) from alcaligenes faecalis n-38a. | a novel type of 5-oxoprolinase was found in a cell extract of strain n-38a, which was later identified as alcaligenes faecalis. the enzyme in the cell extract was purified to a homogeneous state with a yield of 16.6%. the molecular weight of the purified enzyme was estimated to be 47,000 by both sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration, suggesting that the enzyme is a monomeric protein. the enzyme specifically catalyzed a decyclization of l-pyroglutamate witho ... | 1999 | 9925605 |
| the chlorocatechol-catabolic transposon tn5707 of alcaligenes eutrophus nh9, carrying a gene cluster highly homologous to that in the 1,2,4-trichlorobenzene-degrading bacterium pseudomonas sp. strain p51, confers the ability to grow on 3-chlorobenzoate. | alcaligenes eutrophus (ralstonia eutropha) nh9, isolated in japan, utilizes 3-chlorobenzoate as its sole source of carbon and energy. sequencing of the relevant region of plasmid penh91 from strain nh9 revealed that the genes for the catabolic enzymes were homologous to the genes of the modified ortho-cleavage pathway. the genes from strain nh9 (cbnr-abcd) showed the highest homology (89 to 100% identity at the nucleotide level) to the tcbr-cdef genes on plasmid pp51 of the 1,2,4-trichlorobenzen ... | 1999 | 9925607 |
| estimating bacterial growth parameters by means of detection times. | we developed a new numerical method to estimate bacterial growth parameters by means of detection times generated by different initial counts. the observed detection times are subjected to a transformation involving the (unknown) maximum specific growth rate and the (known) ratios between the different inoculum sizes and the constant detectable level of counts. we present an analysis of variance (anova) protocol based on a theoretical result according to which, if the specific rate used for the ... | 1999 | 9925608 |
| isolation of a bacterial strain able to degrade branched nonylphenol. | conventional enrichment of microorganisms on branched nonylphenol (np) as only carbon and energy source yielded mixed cultures able to grow on the organic compound. however, plating yielded no single colonies capable, alone or in combination with other isolates, of degrading the np in liquid culture. therefore, a special approach was used, referred to as "serial dilution-plate resuspension," to reduce culture complexity. in this way, one isolate, ttnp3, tentatively identified as a sphingomonas s ... | 1999 | 9925611 |
| effect of aromatic compounds on cellular fatty acid composition of rhodococcus opacus. | in cells of rhodococcus opacus gm-14, gm-29, and 1cp, the contents of branched (10-methyl) fatty acids increased from 3% to 15 to 34% of the total fatty acids when the cells were grown on benzene, phenol, 4-chlorophenol, chlorobenzene, or toluene as the sole source of carbon and energy, in comparison with cells grown on fructose. in addition, the content of trans-hexadecenoic acid increased from 5% to 8 to 18% with phenol or chlorophenol as the carbon source. the 10-methyl branched fatty acid co ... | 1999 | 9925629 |
| cloning, sequencing, and expression in escherichia coli of d-hydantoinase gene from pseudomonas putida. | 1998 | 9928097 | |
| [antigenic mapping of cytochrome p450 101 (p450cam)]. | eighteen linear antigenic sites were found in cytochrome p450 101 (p450cam) from pseudomonas putida by the peptide scanning method. these sites accounted for about 30% of the protein sequence. we found no sequences that completely coincided with the antigenic sites of p450cam in cytochromes p450 from other sources. the linear b-epitopes of p540cam were mainly localized on the boundaries separating the elements of the secondary structure. seventeen of eighteen antigenic sites were found to be on ... | 1998 | 9929735 |
| cloning and sequence analysis of two catechol-degrading gene clusters from the aniline-assimilating bacterium frateuria species ana-18. | the aniline-assimilating bacterium frateuria species ana-18 produced two catechol 1,2-dioxygenases, cd i and cd ii, and two muconate cycloisomerases, mc i and mc ii. the cata genes cata1 and cata2 encoding cd i and cd ii, respectively, were cloned from a gene library of this bacterium. the cata1 gene was clustered with catb1 encoding mc i, catc1 encoding muconolactone isomerase (mi), catd encoding beta-ketoadipate enol-lactone hydrolase (elh), and orfr1 encoding a putative lysr-type regulator. t ... | 1999 | 9931486 |
| identification and characterisation of is1383, a new insertion sequence isolated from pseudomonas putida strain h. | a new insertion sequence (is1383) was identified on plasmids from pseudomonas putida strain h and its nucleotide sequence was determined. is1383 contains perfect terminal inverted repeats of 13-bp flanking a 1.4-kb internal sequence. a single significant open reading frame was identified that can encode a 342-amino acid polypeptide which was predicted to be highly basic and to have homology to polypeptides known from several other bacterial insertion sequences. at least six copies of is1383 are ... | 1999 | 9933934 |