Publications

TitleAbstractYear(sorted descending)
Filter
PMID
Filter
identification of exopolysaccharides produced by fluorescent pseudomonads associated with commercial mushroom (agaricus bisporus) production.the acidic exopolysaccharides (epss) from 63 strains of mushroom production-associated fluorescent pseudomonads which were mucoid on pseudomonas agar f medium (paf) were isolated, partially purified, and characterized. the strains were originally isolated from discolored lesion which developed postharvest on mushroom (agaricus bisporus) caps or from commercial lots of mushroom casing medium. an acidic galactoglucan, previously named marginalan, was produced by mucoid strains of the saprophyte ps ...19957574589
possible regulatory role for nonaromatic carbon sources in styrene degradation by pseudomonas putida ca-3.styrene metabolism in styrene-degrading pseudomonas putida ca-3 cells has been shown to proceed via styrene oxide, phenylacetaldehyde, and phenylacetic acid. the initial step in styrene degradation by strain ca-3 is oxygen-dependent epoxidation of styrene to styrene oxide, which is subsequently isomerized to phenylacetaldehyde. phenylacetaldehyde is then oxidized to phenylacetic acid. styrene, styrene oxide, and phenylacetaldehyde induce the enzymes involved in the degradation of styrene to phen ...19957574594
expression vectors for the use of eukaryotic luciferases as bacterial markers with different colors of luminescence.an easy way to identify microorganisms is to provide them with gene markers that confer a unique phenotype. several genetic constructions were developed to use eukaryotic luciferase genes for bacterial tagging. the firefly and click bettle luciferase genes, luc and lucor, respectively, were cloned under constitutive control and regulated control from different transcriptional units driven by p1, lambda pr, and ptrc promoters. comparison of the expression of each gene in escherichia coli cells fr ...19957574604
nucleotide sequence analysis of genes encoding a toluene/benzene-2-monooxygenase from pseudomonas sp. strain js150.it was previously shown by others that pseudomonas sp. strain js150 metabolizes benzene and alkyl- and chloro-substituted benzenes by using dioxygenase-initiated pathways coupled with multiple downstream metabolic pathways to accommodate catechol metabolism. by cloning genes encoding benzene-degradative enzymes, we found that strain js150 also carries genes for a toluene/benzene-2-monooxygenase. the gene cluster encoding a 2-monooxygenase and its cognate regulator was cloned from a plasmid carri ...19957574644
quantification of the effect of substrate concentration on the conjugal transfer rate of the tol plasmid in short-term batch mating experiments.batch mating experiments with pseudomonas putida paw 1 (tol) as a donor and pseudomonas aeruginosa pao 1162 as a recipient strain were performed to quantify the effect of the substrate concentration in the mating medium on the observed plasmid transfer rate coefficient. the impact of the substrate concentration in the mating medium was highly correlated with the growth history of the donor strain. when the donor strain was harvested in exponential growth phase, no impact was observed; when the d ...19957576502
the 2fe2s centres of the 2-oxo-1,2-dihydroquinoline 8-monooxygenase from pseudomonas putida 86 studied by epr spectroscopy.the 2-oxo-1,2-dihydroquinoline 8-monooxygenase from pseudomonas putida 86 comprises two components with four redox active sites necessary for activity. we present an epr characterization of the iron-sulfur centres in the purified reductase and oxygenase component of this novel enzyme system. the oxygenase component was identified as a rieske [2fe2s] protein on the basis of its characteristic epr spectrum with gz,y,x = 2.01, 1.91, 1.76 and gav = 1.893. the reductase component, an iron-sulfur flav ...19957578219
[modification of the ortho-route in pseudomonas putida strain 87: purification and properties of dienlactone hydrolase].dienelactone hydrolase (dlh) was purified to electrophoretic homogeneity from the biomass of the pseudomonas putida strain 87 grown on 3-chlorobenzoate. the specific activity of the purified enzyme is 50.5 u./mg of protein. the enzyme is a monomer with a molecular mass of 22 kda, has a ph optimum at 7.6 and is active within a broad temperature range (20-45 degrees c). the enzyme activity is inhibited by pcmb (which requires up to two equivalents of the reagent) but not by edta. the vmax values o ...19957578578
use of haloacetate dehalogenase genes as selection markers for escherichia coli and pseudomonas vectors.the haloacetate dehalogenase gene, dehh2, cloned from moraxella sp. strain b could be used a selection marker gene for vectors in escherichia coli and pseudomonas putida. haloacetates, especially iodoacetate, inhibit the growth of some microorganisms. the dehh2 gene introduced into the cells conferred iodoacetate resistance on them. therefore, e. coli and p. putida transformed with vectors marked with dehh2 could be easily selected on plates containing iodoacetate.19957579995
the nucleotide sequence of a transposable haloalkanoic acid dehalogenase regulatory gene (dehri) from pseudomonas putida strain pp3 and its relationship with sigma 54-dependent activators.the mobile genetic element, deh found in pseudomonas putida pp3 carries a 2-haloalkanoic acid dehalogenase structural gene, dehi, and its associated regulatory gene, dehri. the nucleotide sequence of dehri was determined. the gene had an open reading frame putatively encoding for a 64 kda protein containing 571 amino acid residues. the protein was similar to previously published sequences of several other sigma 54-dependent activator proteins. amino acid sequence analysis showed that the deduced ...19957579999
the use of two-dimensional gradient plates to investigate the range of conditions under which conjugal plasmid transfer occurs.gel-stabilized two-dimensional gradient plates were used to study the effects of ph, salt concentration and temperature on the conjugal transfer of plasmid rp4 between strains of escherichia coli and pseudomonas putida. the combinations of ph and salt concentration that permitted conjugation were mapped as a two-dimensional growth area occupied by transconjugants following conjugation. this conjugation domain was less extensive than the areas that supported growth of the parental strains, and sh ...19957582032
extraction and purification of microbial dna from petroleum-contaminated soils and detection of low numbers of toluene, octane and pesticide degraders by multiplex polymerase chain reaction and southern analysis.we investigated the use of multiplex polymerase chain reaction (pcr) techniques coupled with southern analysis to detect xenobiotic-degrading organisms that had been added to three soils. two soils highly contaminated with petroleum hydrocarbons and a less contaminated control soil were amended with tenfold dilutions of pseudomonas putida mt-2 (pww0), p. oleovorans (oct), and alcaligenes eutrophus jmp134 (pjp4), or, for controls, phosphate buffer alone. total dna was then isolated from the soils ...19957582166
low temperature growth, freezing survival, and production of antifreeze protein by the plant growth promoting rhizobacterium pseudomonas putida gr12-2.the plant growth promoting rhizobacterium pseudomonas putida gr12-2 was originally isolated from the rhizosphere of plants growing in the canadian high arctic. here we report that this bacterium was able to grow and promote root elongation of both spring and winter canola at 5 degrees c, a temperature at which only a relatively small number of bacteria are able to proliferate and function. in addition, the bacterium survived exposure to freezing temperatures, i.e., -20 and -50 degrees c. in an e ...19957585354
sequence and expression of the bpdc1c2bade genes involved in the initial steps of biphenyl/chlorobiphenyl degradation by rhodococcus sp. m5.the nucleotide (nt) sequence of the bpdc1c2bade genes which encode the first three enzymes in the biphenyl (bp) degradation pathway of gram+ rhodococcus sp. m5 (formerly arthrobacter m5) was determined. except for the ferredoxin component (bpdb) of the initial bp dioxygenase, the predicted amino acid (aa) sequences of the remaining proteins are found to be more closely related to the counterpart proteins (todc1c2bade) present in the toluene-degrader, pseudomonas putida f1, than those of three bp ...19957590299
desaturation and oxygenation of 1,2-dihydronaphthalene by toluene and naphthalene dioxygenase.bacterial strains expressing toluene and naphthalene dioxygenase were used to examine the sequence of reactions involved in the oxidation of 1,2-dihydronaphthalene. toluene dioxygenase of pseudomonas putida f39/d oxidizes 1,2-dihydronaphthalene to (+)-cis-(1s,2r)-dihydroxy-1,2,3,4-tetrahydronaphthalene, (+)-(1r)-hydroxy-1,2-dihydronaphthalene, and (+)-cis-(1r,2s)-dihydroxy-1,2-dihydronaphthalene. in contrast, naphthalene dioxygenase of pseudomonas sp. strain ncib 9816/11 oxidizes 1,2-dihydronaph ...19957592326
formation of indigo and related compounds from indolecarboxylic acids by aromatic acid-degrading bacteria: chromogenic reactions for cloning genes encoding dioxygenases that act on aromatic acids.the p-cumate-degrading strain pseudomonas putida f1 and the m- and p-toluate-degrading strain p. putida mt-2 transform indole-2-carboxylate and indole-3-carboxylate to colored products identified here as indigo, indirubin, and isatin. a mechanism by which these products could be formed spontaneously following dioxygenase-catalyzed dihydroxylation of the indolecarboxylates is proposed. indolecarboxylates were employed as chromogenic substrates for identifying recombinant bacteria carrying genes e ...19957592495
production and application of monoclonal antibodies specific to pyrroloquinoline quinone.we produced five monoclonal antibodies (mabs 1, 2, 6, 7, and 9) that are specific to pyrroloquinoline quinone (pqq). pqq-conjugated hemocyanin was used for the immunization of mice and the hybridomas were selected using pqq-conjugated bsa in an enzyme-linked immunosorbent assay. mabs 2 and 9 were of the igg1 isotype. both could recognize free pqq, the former probably at the o-quinone and the latter at the opposite side of the molecule. they did not bind with trihydroxyphenylalanine, dihydroxyphe ...19957592546
differential dna bending introduced by the pseudomonas putida lysr-type regulator, catr, at the plasmid-borne pheba and chromosomal catbc promoters.the plasmid-borne pheba operon of pseudomonas putida strain paw85 allows growth of the host cells on phenol. the promoter of this operon is activated by the chromosomally encoded lysr-type regulator catr, in the presence of the inducer cis,cis-muconate. cis,cis-muconate is an intermediate of catechol degradation by the chromosomally encoded ortho or beta-ketoadipate pathway. the catbc operon encodes two enzymes of the beta-ketoadipate pathway and also requires catr and cis,cis-muconate for its e ...19957596284
the sigma 54-dependent promoter ps of the tol plasmid of pseudomonas putida requires hu for transcriptional activation in vivo by xylr.in the presence of toluene and xylenes, the sigma 54-dependent ps promoter of the tol (toluene biodegradation) plasmid pww0 of pseudomonas putida is activated at a distance by the xylr protein, of the ntrc family of transcriptional regulators. since contacts between xylr bound to upstream activating sites and the rna polymerase require the looping out of the intervening dna segment, the intrinsic curvature, the bendability of the corresponding sequence, and the spatial effects of protein-induced ...19957601841
evidence that operons tcb, tfd, and clc encode maleylacetate reductase, the fourth enzyme of the modified ortho pathway.the maleylacetate reductase from pseudomonas sp. strain b13 functioning in the modified ortho pathway was purified and digested with trypsin. the polypeptides separated by high-performance liquid chromatography were sequenced. alignments with the polypeptides predicted from the tfdf and tcbf genes located on plasmids pjp4 of the 2,4-dichlorophenoxyacetate-degrading alcaligenes eutrophus jmp134 and pp51 of the 1,2,4-trichlorobenzene-degrading pseudomonas sp. strain p51 as well as polypeptides pre ...19957601858
autoinducer-mediated regulation of rhamnolipid biosurfactant synthesis in pseudomonas aeruginosa.the opportunistic human pathogen pseudomonas aeruginosa produces a variety of virulence factors, including exotoxin a, elastase, alkaline protease, alginate, phospholipases, and extracellular rhamnolipids. the previously characterized rhlabr gene cluster encodes a regulatory protein (rhlr) and a rhamnosyltransferase (rhlab), both of which are required for rhamnolipid synthesis. another gene, rhii, has now been identified downstream of the rhlabr gene cluster. the putative rhli protein shares sig ...19957604006
cloning of the ppu21im gene using a in vivo selection method.a genetic system enabling the in vivo selection of genes encoding the dna-modifying enzymes was developed. a gene library is transformed into a strain harboring the restriction-modification (r-m) system which a recognition sequence is a subset of the target sequence of the dna methyltransferase (mtase) to be cloned. if the residing mtase is temperature sensitive, the inability of transformants to grow at 42 degrees c provides a simple and convenient procedure for the isolation of new mtase-encod ...19957607525
isolation and expansion of the catabolic potential of a pseudomonas putida strain able to grow in the presence of high concentrations of aromatic hydrocarbons.pseudomonas putida dot-t1 was isolated after enrichment on minimal medium with 1% (vol/vol) toluene as the sole c source. the strain was able to grow in the presence of 90% (vol/vol) toluene and was tolerant to organic solvents whose log p(ow) (octanol/water partition coefficient) was higher than 2.3. solvent tolerance was inducible, as bacteria grown in the absence of toluene required an adaptation period before growth restarted. mg2+ ions in the culture medium improved solvent tolerance. elect ...19957608060
biosensing of benzene derivatives in the environment by luminescent escherichia coli.sensitive and convenient biosensing of environmental pollutants has been developed by fusing a gene of firefly luciferase to the tol plasmid. tol plasmid of pseudomonas putida encodes a series of enzymes for degradation of benzene and its derivatives. the expression of these enzymes is controlled with the regulating proteins xylr and xyls, whose promoters are activated in the presence of aromatic compounds. the structural gene of firefly luciferase, as a reporter enzyme, was inserted under the c ...19957612210
cyclodextrin-enhanced degradation of toluene and p-toluic acid by pseudomonas putida.degradation of an immiscible aromatic solvent, toluene, and a water-soluble aromatic compound, p-toluic acid, by a pseudomonas putida strain in the presence of beta-cyclodextrin (beta-cd) was investigated. the ability of cds to interact with hydrophobic organics and form inclusion compounds was exploited in this study to remove or alleviate the toxicities of substrates and consequently to enable or enhance degradation. liquid toluene was found to be highly toxic to p. putida. however, this phase ...19957618884
simultaneous chromium reduction and phenol degradation in a coculture of escherichia coli atcc 33456 and pseudomonas putida dmp-1.in a defined coculture of a cr(vi) reducer, escherichia coli atcc 33456, and a phenol degrader, pseudomonas putida dmp-1, simultaneous reduction of cr(vi) and degradation of phenol was observed. when cr(vi) was present in the coculture, quantitative transformation of cr(vi) into cr(iii) proceeded with simultaneous degradation of phenol. cr(vi) reduction was correlated to phenol degradation in the coculture as demonstrated by a regression analysis of the cumulative cr(vi) reduction and the cumula ...19957618887
iron-ligand structure and iron redox property of nitric oxide reductase cytochrome p450nor from fusarium oxysporum: relevance to its no reduction activity.we studied the nitric oxide reductase, cytochrome p450nor, purified from a denitrifying fungus fusarium oxysporum with electron paramagnetic resonance spectral and redox potential measurements. the epr spectral features of p450nor in the ferric resting, the ferric cyanide-bound, and the ferrous no-bound forms were the same as the corresponding ones of other general p450s such as pseudomonas putida p450cam. in contrast, the metyrapone complex of ferric p450nor gave an epr spectrum with significan ...19957619804
iron regulation of siderophore biosynthesis and transport in pseudomonas putida wcs358: involvement of a transcriptional activator and of the fur protein.pseudobactin 358 is the yellow-green fluorescent siderophore produced by pseudomonas putida wcs358 in conditions of iron limitation. the genes encoding for siderophore biosynthesis are iron-regulated at the transcriptional level. previous work has shown that a positive regulator, pfra, is absolutely required for the activation under iron-limiting conditions of pseudobactin 358 biosynthesis. in this study we identified a set of tn5 insertion mutants of strain wcs358 which lost the ability to acti ...19957623664
degradation of polycyclic aromatic hydrocarbons (pahs) by a mixed culture and its component pure cultures, obtained from pah-contaminated soil.a mixed culture, isolated from soil contaminated with polycyclic aromatic hydrocarbons (pahs), grew on and degraded fluoranthene in aqueous media supplemented with glucose, yeast extract, and peptone. increased complex nitrogen levels in the medium promoted bacterial growth and a greater extent of fluoranthene degradation. amendment of the media with high glucose levels also diminished specific fluoranthene degradation. the mixed culture was capable of degrading a range of other pahs, including ...19957627907
identification of a lysine residue in the nadh-binding site of salicylate hydroxylase from pseudomonas putida s-1.salicylate hydroxylase from pseudomonas putida s-1 was irreversibly inactivated by trinitrobenzenesulfonic acid (tnbs). the reaction was linearly dependent on tnbs concentration and the second-order rate constant was 120 m-1.min-1 for the holoprotein at ph 8.5. modification of one mole of lysine residue per mole of enzyme caused a large loss of the activity, and the enzyme was no longer able to show nadh-dehydrogenase activity after uncoupling. the presence of nadh, nad+, atp, or amp afforded pr ...19957629025
overexpression of pseudomonas putida catechol 2,3-dioxygenase with high specific activity by genetically engineered escherichia coli.the cloned xyle gene encoding catechol 2,3-dioxygenase (metapyrocatechase) from tol plasmid in pseudomonas putida mt-2 has been expressed in escherichia coli w3110 to a level of approximately 15% of the total soluble protein. of the total iron in the crude extract, 45% was on the enzyme. the crystallized enzyme from e. coli had higher iron content (3.7 mol/mol enzyme) and specific activity (536 u/mg) than the enzyme from p. putida mt-2. however, no differences were observed in physicochemical, p ...19957629031
2-oxo-1,2-dihydroquinoline 8-monooxygenase, a two-component enzyme system from pseudomonas putida 86.2-oxo-1,2-dihydroquinoline 8-monooxygenase, which catalyzes the nadh-dependent oxygenation of 2-oxo-1,2-dihydroquinoline to 8-hydroxy-2-oxo-1,2-dihydroquinoline, is the second enzyme in the quinoline degradation pathway of pseudomonas putida 86. this enzyme system consists of two inducible protein components, which were purified, characterized, and identified as reductase and oxygenase. the yellow reductase is a monomeric iron-sulfur flavoprotein (m(r), 38,000), containing flavin adenine dinucle ...19957629085
integration host factor suppresses promiscuous activation of the sigma 54-dependent promoter pu of pseudomonas putida.in the presence of m-xylene, the pu promoter of the tol plasmid of pseudomonas putida is activated by the prokaryotic enhancer-binding protein xylr. the intervening dna segment between the upstream activating sequences (uass) and those for rna polymerase binding contains an integration host factor (ihf) attachment site that is required for full transcriptional activity. in the absence of ihf, the pu promoter can be cross-activated by other members of the sigma 54-dependent family of regulatory p ...19957638181
assessment of rapid bioassays for detecting cyanobacterial toxicity.simple and easy-to-use bioassays with artemia salina (brine shrimp) larvae, luminescent bacteria and pseudomonas putida were evaluated for the detection of toxicity due to cyanobacterial hepato- and neurotoxins. the hepatotoxins and a neurotoxin, anatoxin-a, were extracted from laboratory-grown cultures and natural bloom samples by the solid phase fractionation method and dissolved in diluent for different bioassays. the toxin concentration of cyanobacterial extracts was determined with hplc. th ...19957639991
catabolite-mediated mutations in alternate toluene degradative pathways in pseudomonas putida.pseudomonas putida 54g grew on mineral salts with toluene and exhibited catechol-2,3-dioxygenase (c23o) activity, indicating a meta pathway. after 10 to 15 days on toluene, nondegrading (tol-) variants approached nearly 10% of total cfu. auxotrophs were not detected among variants, suggesting selective loss of catabolic function(s). variant formation was substrate dependent, since tol- cells were observed on neither ethylbenzene, glucose, nor peptone-based media nor when toluene catabolism was s ...19957642499
cloning, dna sequencing, and amino acid sequencing of catechol 1,2-dioxygenases (pyrocatechase) from pseudomonas putida mt-2 and pseudomonas arvilla c-1.catechol 1,2-dioxygenase catalyzes the oxygenative ring cleavage of catechol to form cis,cis-muconic acid and is encoded by a cata gene. we have cloned a cata gene from pseudomonas putida mt-2 using a pcr product of amino acid sequence-based primers as a probe. the amino acid sequence deduced from the 930 nucleotides was in complete agreement with the chemically determined sequence of the protein. crude extracts of escherichia coli cells carrying the cata gene downstream from the lac promoter sh ...19957646060
energy-coupled transport and signal transduction through the gram-negative outer membrane via tonb-exbb-exbd-dependent receptor proteins.iron in the form of ferric siderophore complexes and vitamin b12 are transported through the outer membrane of gram-negative bacteria by a mechanism which consumes energy. there is no known energy source in the outer membrane or in the adjacent periplasmic space so that energy is provided by the electrochemical potential across the cytoplasmic membrane. energy flows from the cytoplasmic into the outer membrane via a complex consisting of the tonb, exbb and exbd proteins which are anchored in the ...19957654405
isolation of ice-nucleating active bacteria from the freeze-tolerant frog, rana sylvatica.ice-nucleating active (ina) bacteria were isolated from the gut of field-collected freeze-tolerant wood frogs (rana sylvatica) collected in winter. thirteen strains of pseudomonas fluorescens, four strains of pseudomonas putida, and two strains of enterobacter agglomerans had ice-nucleating activity. each of the ina pseudomonad strains was psychrophilic. p. putida strains were differentiated from p. fluorescens strains by gelatinase, lecithinase, and lipase production. the maximum nucleation tem ...19957656570
purification and crystallization of benzoylformate decarboxylase.a new large-scale purification method for benzoylformate decarboxylase from pseudomonas putida has allowed us to undertake an x-ray crystallographic study of the enzyme. the previously observed instability of the enzyme was overcome by addition of 100 microm thiamine pyrophosphate to buffers used in the purification. the final enzyme preparation was more than 97% pure, as determined by denaturing gel electrophoresis and densitometry. the mobility of the enzyme on a gel filtration column indicate ...19957663351
growth phase-dependent induction of stationary-phase promoters of escherichia coli in different gram-negative bacteria.rsf1010-derived plasmids carrying a fusion of a promoterless lacz gene with the sigma s-dependent growth phase-regulated promoters of escherichia coli, bolap1 and fic, were constructed. the plasmids were mobilized into the gram-negative bacterial species acetobacter methanolicus, xanthomonas campestris, pseudomonas putida, and rhizobium meliloti. the beta-galactosidase activities of bacterial cultures were determined during exponential and stationary growth phases. transcriptional activation of ...19957665531
nucleotide sequence of the gene for a thermostable esterase from pseudomonas putida mr-2068.the esterase gene (est) of pseudomonas putida mr-2068 was cloned into escherichia coli jm109. an 8-kb inserted dna directed synthesis of an esterase in e. coli. the esterase gene was in a 1.1-kb psti-clai fragment within the insert dna. the complete nucleotides of the dna fragment containing the esterase gene were sequenced and found to include a single open reading frame of 828 bp coding for a protein of 276 amino acid residues. the open reading frame was confirmed by n-terminal amino acid sequ ...19957670178
[frequency of clinical isolation of glucose non-fermentative gram-negative rods and their susceptibilities to antibacterial agents].a comparison was made for frequencies of isolation o glucose non-fermentative gram-negative rods ((g)nf-gnr) from clinical specimens during a period from july, 1986 to june, 1987 (the first period) and that from january, 1994 to december, 1994 (the second period). also, minimum inhibitory concentrations of principal drugs were determined against these isolates. the obtained results are summarized as follows: 1. thirty four (34) species of (g)nf-gnr were found from 35,200 clinical specimens in th ...19957474336
multiple outer membrane receptors for uptake of ferric pseudobactins in pseudomonas putida wcs358.under iron limitation pseudomonas putida wcs358 produces a fluorescent siderophore, pseudobactin 358, which, after complexing iron, is transported back into the cell via the specific outer membrane receptor pupa. in addition, this strain has the capacity to take up iron via a large variety of siderophores produced by other fluorescent pseudomonads. putative receptor genes for such siderophores were identified in the chromosome of strain wcs358 by pcr using primers matching two domains conserved ...19957476877
transformations of morphine alkaloids by pseudomonas putida m10.the oxidation of morphine by washed-cell incubations of pseudomonas putida m10 gave rise to a large number of transformation products including hydromorphone (dihydromorphinone), 14 beta-hydroxymorphine, 14 beta-hydroxymorphinone, and dihydromorphine. similarly, in incubations with oxymorphone (14 beta-hydroxydihydromorphinone) as substrate, the major transformation product was identified as oxymorphol (14 beta-hydroxydihydromorphine). the identities of all these biological products were confirm ...19957487001
role of competition for inorganic nutrients in the biodegradation of mixtures of substrates.a study was conducted to determine whether competition for inorganic nutrients affects the biodegradation of mixtures of substrates. little benzylamine was mineralized by pseudomonas putida in solutions with no added p, but the substrate was degraded if the medium contained 100 nm p. the enhancement by p addition did not occur if the medium also contained caprolactam and a caprolactam-utilizing strain of pseudomonas aeruginosa. the suppression by the second bacterium was overcome by a higher p c ...19957487018
construction and behavior of biologically contained bacteria for environmental applications in bioremediation.the survival of microorganisms can be predicted through the use of active biological containment systems. we have constructed contained pseudomonas putida strains that degrade alkylbenzoates. the modified strain carries a fusion of the plac promoter to the gef gene, which encodes a killing protein. expression from plac is controlled through a regulatory cascade, so that plac is switched on or off by the absence or presence of alkylbenzoates, respectively. similar uncontained strains were also co ...19957487030
production of a form-specific, inhibitory antibody against rat cytochrome p450 2b1 using a synthetic peptide antigen against a putative substrate binding site.rat cytochrome p450 2b1 antipeptide antibodies were produced by immunizing rabbits with a synthetic peptide antigen. the anti-cyp2b1 igg obtained did not cross-react with cyp2b2, which has 97% identity in primary sequence of cyp2b1. this result demonstrates that a difference of 2 amino acid residues among 12 is sufficient to produce a form-specific antibody. the cyp2b1 antipeptide igg inhibited pentoxyresorufin o-dealkylase activity of microsomes obtained from phenobarbital-treated rats in a dos ...19957488175
pollution of modern metalworking fluids containing biocides by pathogenic bacteria in france. reexamination of chemical treatments accuracy.pollution by pathogenic bacteria was examined in 150 french metalworking fluid samples. gram-negative micro-organisms such as salmonella spp., shigella spp., and vibrio spp. as well as gram-positive cocci were never isolated. nevertheless opportunistic pathogens such as pseudomonas aeruginosa and klebsiella pneumoniae still contaminated these fluids with an isolation frequency of 17% of samples for each. these two micro-organisms failed to grow or even survive in vitro in sterile cutting fluids ...19957489767
dissection of the core and auxiliary sequences in the vegetative replication origin of promiscuous plasmid rk2.the vegetative replication origin (oriv) of promiscuous incp plasmid rk2 can function in many gram-negative bacterial species when supplied with the plasmid-encoded replication protein trfa and host-encoded replication proteins including dnaa. nine trfa binding sites (iterons) are known, and also two dnaa binding sites, box 1, between trfa iterons 4 and 5, and box 2, downstream of repeat 9. the deletion analysis presented here shows that the core oriv requires dnaa box 1 for function in escheric ...19957500337
the refined x-ray structure of muconate lactonizing enzyme from pseudomonas putida prs2000 at 1.85 a resolution.we report here the refined x-ray crystal structure of muconate lactonizing enzyme (mle) from pseudomonas putida prs2000 at a resolution of 1.85 a with an r-factor of 16.8%. an enzyme from the beta-ketoadipate pathway, mle catalyses the conversion of cis,cis-muconate to muconolactone. it is a homo-octamer, one monomer consisting of 373 amino acid residues. mle has two large domains and a c-terminal subdomain: an alpha + beta domain, an alpha beta-barrel domain and a c-terminal meandering subdomai ...19957500361
cryptic dehalogenase and chloroamidase genes in pseudomonas putida and the influence of environmental conditions on their expression.mutants of two strains of pseudomonas putida expressed two cryptic chloroamidases (c-amidase and h-amidase) and one cryptic dehalogenase (dehii). the mutants were selected on either 2-chloropropionamide (2cpa) or 2-monochloropropionate (2mcpa), developing as papillae in parental colonies growing on a metabolisable support substrate. mutants expressing c-amidase were selected if 2cpa was utilised as either a carbon or a nitrogen source. h-amidase mutants were selected only if 2cpa was used as a n ...19957710321
tetrameric structure and cellular location of catechol 2,3-dioxygenase.catechol 2,3-dioxygenase from the meta-cleavage pathway encoded on the tol plasmid of pseudomonas putida (pwwo) was investigated by electron microscopy. negatively stained samples of the purified catechol 2,3-dioxygenase revealed that the enzyme consists of four subunits arranged in a tetrahedral conformation. monoclonal antibodies raised against catechol 2,3-dioxygenase showed highly specific reactions and were used to localize the enzyme in escherichia coli (paw31) and p. putida (pwwo), using ...19957710322
effect of cellular physiology on pcr amplification efficiency.culture conditions, and other variables that modulate a cell's physiology, can bias a polymerase chain reaction (pcr) amplification against generating a representative population profile. two pseudomonas putida nahr alleles were constructed in puc19 that differ solely in a 31-bp internal segment whose sequence has been inverted. after pcr amplification, the products could be distinguished on the basis of a change in a unique restriction site. when an escherichia coli strain carrying one nahr all ...19957711949
a two-protein component 7 alpha-cephem-methoxylase encoded by two genes of the cephamycin c cluster converts cephalosporin c to 7-methoxycephalosporin c.two genes, cmci and cmcj, corresponding to open reading frames 7 and 8 (orf7 and orf8) of the cephamycin c cluster of nocardia lactamdurans encode enzymes that convert cephalosporin c to 7-methoxycephalosporin c. proteins p7 and p8 (the products of orf7 and orf8 expressed in streptomyces lividans) introduce the methoxyl group at c-7 of the cephem nucleus. efficient hydroxylation at c-7 and transfer of the methyl group from s-adenosylmethionine require both proteins p7 and p8, although p7 alone s ...19957721717
comparative ribosomal protein sequence analyses of a phylogenetically defined genus, pseudomonas, and its relatives.i analyzed various families of ribosomal proteins obtained from selected species belonging to the genus pseudomonas sensu stricto and allied organisms which were previously classified in the genus pseudomonas. partial amino acid sequencing of l30 preparations revealed that the strains which i examined could be divided into three clusters. the first cluster, which was assigned to the genus pseudomonas sensu stricto, included pseudomonas aeruginosa, pseudomonas putida, pseudomonas mendocina, and p ...19957727274
three distinct quinoprotein alcohol dehydrogenases are expressed when pseudomonas putida is grown on different alcohols.a bacterial strain that can utilize several kinds of alcohols as its sole carbon and energy sources was isolated from soil and tentatively identified as pseudomonas putida hk5. three distinct dye-linked alcohol dehydrogenases (adhs), each of which contained the prosthetic group pyrroloquinoline quinone (pqq), were formed in the soluble fractions of this strain grown on different alcohols. adh i was formed most abundantly in the cells grown on ethanol and was similar to the quinoprotein adh repor ...19957730276
identification of active site residues by site-directed mutagenesis of delta 5-3-ketosteroid isomerase from pseudomonas putida biotype b.in order to assess the roles of specific amino acid residues in the delta 5-3-ketosteroid isomerase from pseudomonas putida biotype b during catalysis, we replaced aspartic acid 40 with asparagine (d40n) and tyrosine 16 with phenylalanine (y16f) in the enzyme by site-directed mutagenesis. both purified mutant enzymes resulted in profound decreases in catalytic activities, 10(3.3)-fold in the y16f mutant and 10(6.2)-fold in the d40n mutant. aspartic acid 40 and tyrosine 16 of the enzyme are the c ...19957730300
the evolutionary relationship of biphenyl dioxygenase from gram-positive rhodococcus globerulus p6 to multicomponent dioxygenases from gram-negative bacteria.the gram+ bacterium rhodococcus globerulus p6 (rgp6) catabolizes a range of polychlorinated biphenyl (pcb) congeners, thus being of interest in bioelimination processes for pcb. the first step in the pathway, a dioxygenase attack of one of the biphenyl (bp) rings, is catalyzed by biphenyl dioxygenase (bdo). in this study, the nucleotide (nt) sequences of the four clustered cistrons, bpha1a2a3a4, encoding the subunits of bdo and forming part of the bph operon of rgp6 for bp degradation, were dete ...19957737502
substrate specificity differences between two catechol 2,3-dioxygenases encoded by the tol and nah plasmids from pseudomonas putida.the substrate specificities of two catechol 2,3-dioxygenases, one encoded by xyle on the tol plasmid pww0 and the other encoded by nahh on the nah7 plasmid, were investigated. the xyle catechol 2,3-dioxygenase catalyzes the ring-cleavage of catechol, 3-methylcatechol and 4-methylcatechol. the nahh catechol 2,3-dioxygenase was partially deficient in oxidizing 3-methylcatechol due to defects in two catalytic properties. first, nahh has a lower kcat value for 3-methylcatechol compared to xyle, and ...19957744021
purification and characterization of an atp-dependent amidohydrolase, n-methylhydantoin amidohydrolase, from pseudomonas putida 77.n-methylhydantoin amidohydrolase, an atp-dependent amidohydrolase involved in microbial degradation of creatinine, was purified 70-fold to homogeneity, with a 62% overall recovery, and was crystallized from pseudomonas putida 77. the enzyme has a relative molecular mass of 300,000. it is a tetramer of two identical small subunits (m(r) 70,000) and two identical large subunits (m(r) 80,000). the enzyme requires atp for the amidohydrolysis of n-methylhydantoin and vice versa. mg2+, mn2+ or co2+, a ...19957744042
iron-responsive gene expression in pseudomonas fluorescens m114: cloning and characterization of a transcription-activating factor, pbra.in response to iron limitation. pseudomonas fluorescens m114 induces a number of genes including an iron-scavenging siderophore termed pseudobactin m114, its cognate receptor, pbua, and a casein protease. a tn5lacz-induced mutant (m114fa1) was isolated that exhibits a pleiotropic phenotype and lacks the ability to express these iron-regulated genes. a cosmid clone was identified which complements this mutation. this clone is capable of activating a number of iron-regulated promoter fusion constr ...19957746151
[degradation of syntanol ds-10 by bacteria immobilized in polysaccharide gels].degradative capability of bacterium pseudomonas putida immobilized in polysaccharide (agar-agar or furcellarane) gels towards a nonionic surfactant sintanol ds-10 was studied. the immobilized cells were shown to retain their ability to degrade the substrate in the model experiments as well as in the real waste water. the substrate was degraded after adsorption to the carrier beads.19957746826
a homolog of the rhizobium meliloti nitrogen fixation gene fixn is involved in the production of a microaerobically induced oxidase activity in the phytopathogenic bacterium agrobacterium tumefaciens.hybridization analysis using the rhizobium meliloti nitrogen fixation gene fixn as a probe revealed the presence of a homologous dna region in the phytopathogenic bacterium agrobacterium tumefaciens. hybridization signals were also detected with total dnas of rhizobium leguminosarum bv. phaseoli, rhodobacter capsulatus and escherichia coli, but not those of xanthomonas campestris pv. campestris and pseudomonas putida. the hybridizing fragment from a. tumefaciens was cloned and sequenced. the pre ...19957753030
localization and organization of phenol degradation genes of pseudomonas putida strain h.the genetic organization of the dna region encoding the phenol degradation pathway of pseudomonas putida h has been investigated. this strain can utilize phenol or some of its methylated derivatives as its sole source of carbon and energy. the first step in this process is the conversion of phenol into catechol. catechol is then further metabolized via the meta-cleavage pathway into tca cycle intermediates. genes encoding these enzymes are clustered on the plasmid ppgh1. a region of contiguous d ...19957753034
x-ray absorption spectroscopic studies of the fe(ii) active site of catechol 2,3-dioxygenase. implications for the extradiol cleavage mechanism.the extradiol-cleaving catechol 2,3-dioxygenase (2,3-ctd) isolated from pseudomonas putida mt-2 and its catechol and ternary e.s.no complexes are characterized by x-ray absorption spectroscopy (xas). the intensities of the 1s-->3d transitions in the pre-edge spectra of the uncomplexed enzyme and its substrate complex show that the fe(ii) center is five-coordinate in both complexes, in agreement with earlier magnetic circular dichroism studies [mabrouk, p. a., orville, a. m., lipscomb, j. d., & s ...19957756296
random walk calculations for bacterial migration in porous media.bacterial migration is important in understanding many practical problems ranging from disease pathogenesis to the bioremediation of hazardous waste in the environment. our laboratory has been successful in quantifying bacterial migration in fluid media through experiment and the use of population balance equations and cellular level simulations that incorporate parameters based on a fundamental description of the microscopic motion of bacteria. the present work is part of an effort to extend th ...19957756547
cloning, sequence analysis, and expression of the gene encoding formaldehyde dismutase from pseudomonas putida f61.the gene (fdm) coding for formaldehyde dismutase (ec 1.2.99.4) from a genomic library of formaldehyde-tolerant pseudomonas putida f61 was cloned and expressed in escherichia coli. the nucleotides of the cloned dna were sequenced; they included a single open reading frame of 1200 base pairs, coding for a putative protein with a molecular weight of 42,848. sequencing of the first 20 n-terminal amino acid residues and of an internal part of the enzyme purified from p. putida f61 established the ide ...19957766017
use of a polymerase-chain-reaction-amplified dna probe from pseudomonas putida to detect d-hydantoinase-producing microorganisms by direct colony hybridization.pseudomonas putida strain dsm 84 produces n-carbamyl-d-amino acids from the corresponding d-5-monosubstituted hydantoins. the sequence of the d-hydantoinase gene from this strain (genbank accession number l24157) was used to develop a dna probe of 122 base pairs (bp) that could detect d-hydantoinase genes in other bacterial genera by dna and by colony hybridization. under conditions tolerating 32% mismatch, the probe was specific for all strains that expressed d-hydantoinase activity. these incl ...19957766091
biodegradation of 2-chloroethanol by freely suspended and adsorbed immobilized pseudomonas putida us2 in soil.the degradation of 2-chloroethanol by pseudomonas putida us2 was investigated in batch, repeated batch and continuous cultures especially in a packed-bed fermenter with sand. the degradation of 2-chloroethanol was connected with a release of protons, which led to a decrease of the ph in the medium. higher initial concentration than 25 mm 2-chloroethanol were not degraded completely because they entailed a decrease of the ph to 5.0, which inhibited further growth and degradation. p. putida us2 sh ...19957766127
purification and characterization of a cam repressor (camr) for the cytochrome p-450cam hydroxylase operon on the pseudomonas putida cam plasmid.the cytochrome p-450cam hydroxylase operon of pseudomonas putida ppg1 (atcc 17543) encodes proteins responsible for early steps of the degradation of d-camphor. transcription of this operon is negatively controlled by the cam repressor (camr), and the expression of camr is autoregulated. camr was purified from escherichia coli harboring an overproducing plasmid. the repressor forms a homodimer with a molecular mass of 40 kda, as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis ...19957768809
involvement of ihf protein in expression of the ps promoter of the pseudomonas putida tol plasmid.regulation of the xyl gene operons of the pseudomonas putida tol plasmid is mediated by the products of the downstream clustered and divergently oriented xylr and xyls regulatory genes. the xylr-xyls intergenic region contains the xylr and xyls promoters pr and ps, respectively. a binding site for the xylr activator protein is located upstream of ps and overlapping pr. dnase i footprint experiments showed that one of these sites, which overlaps the recognition site for xylr activator, as well as ...19957768832
evidence for a (triosephosphate isomerase-like) "catalytic loop" near the active site of glyoxalase i.the conformational mobility of glyoxalase i (glx i) during catalysis has been probed using stable analogs of the enediol intermediate that forms along the reaction pathway: gsc(o)n(oh)r, where gs = glutathionyl and r = ch3 (1), c6h5 (2), c6h4cl (3), or c6h4br (4). for human erythrocyte glx i, catalysis is unlikely to be coupled to major changes in protein secondary structure, as the circular dichroism spectrum of the enzyme (190-260 nm) is insensitive to saturating concentrations of either enedi ...19957768882
effect of cultivation medium on some physicochemical parameters of outer bacterial membrane.the changes of surface charge and hydrophobicity of the outer bacterial membrane in relation to utilization of n-hexadecane were studied. for this spectrophotometric study adsorption of methylene blue and transport of gentian violet were used. the decrease in the negative charge of the bacterial strains pseudomonas putida ccm 3423, p. aeruginosa, and p. fluorescens ccm 2115, depended on the type of growth medium. the decrease of surface charge was in the order: meat extract peptone broth > miner ...19957770007
nucleotide sequence of the staphylococcus aureus rna polymerase rpob gene and comparison of its predicted amino acid sequence with those of other bacteria.the complete nucleotide sequence of the rpob gene which encodes the beta subunit of s. aureus rna polymerase has been determined. the rpob protein, consists of 1182 amino acids and has a novel initiation codon uug which initiates protein synthesis with methionine. there is a very strong shine-dalgarno complementarity and the -10 and -35 promoter hexameric sequences are taatat and ccgttt, respectively. a rho-dependent termination site, caatcaa, is present which overlaps the -35 promoter sequence ...19957772603
isolation and characterisation of a strain of pseudomonas putida that can express a periplasmic nitrate reductase.a strain of pseudomonas putida that can express a nitrate reductase that is located in the periplasmic compartment was isolated from freshwater. the enzyme was active in vivo during arginine fermentation and at the onset of oxygen limitation in batch cultures. the activity of the enzyme increased the yield of bacteria following fermentative growth under anoxic conditions with arginine, but nitrate reduction did not support growth on non-fermentable carbon substrates under anoxic conditions. cell ...19957778973
pcr amplification and direct sequencing of gyrb genes with universal primers and their application to the detection and taxonomic analysis of pseudomonas putida strains.degenerate pcr primers, up-1 and up-2r, for the amplification of dna gyrase subunit b genes (gyrb) were designed by using consensus amino acid sequences of gyrases from escherichia coli, pseudomonas putida, and bacillus subtilis. in addition to the degenerate sequences, these primers have sequences at the 5' end which allow direct sequencing of amplified pcr products. with these primers, dna segments of the predicted size were amplified from a variety of gram-negative and gram-positive genera. t ...19957793912
characterization of biphenyl catabolic genes of gram-positive polychlorinated biphenyl degrader rhodococcus sp. strain rha1.rhodococcus sp. strain rha1 is a gram-positive polychlorinated biphenyl (pcb) degrader which can degrade 10 ppm of pcb48 (equivalent to aroclor1248), including tri-, tetra-, and pentachlorobiphenyls, in a few days. we isolated the 7.6-kb ecori-bamhi fragment carrying the biphenyl catabolic genes of rha1 and determined their nucleotide sequence. on the basis of deduced amino acid sequence homology, we identified six bph genes, bpha1a2a3a4, bphb, and bphc, that are responsible for the initial thre ...19957793929
combination of the tod and the tol pathways in redesigning a metabolic route of pseudomonas putida for the mineralization of a benzene, toluene, and p-xylene mixture.construction of a hybrid strain which is capable of mineralizing components of a benzene, toluene, and p-xylene mixture simultaneously was attempted by redesigning the metabolic pathway of pseudomonas putida. genetic and biochemical analyses of the tod and the tol pathways revealed that dihydrodiols formed from benzene, toluene, and p-xylene by toluene dioxygenase in the tod pathway could be channeled into the tol pathway by the action of cis-p-toluate-dihydrodiol dehydrogenase, leading to compl ...19957793941
cloning of salicylate hydroxylase gene and catechol 2,3-dioxygenase gene and sequencing of an intergenic sequence between the two genes of pseudomonas putida kf715.the salicylate hydroxylase can convert the salicylate to catechol, and catechol 2,3-dioxygenase catalizes the conversion of catechol to 2-hydroxymuconic semialdehyde. a salicylate hydroxylase gene and a catechol 2,3-dioxygenase have been cloned from chromosomal dna of p. putida kf715. the two genes have different promoters. an open reading frame with 339 nucleotides preceded by a putative ribosome-binding sequence (ggagg) was identified in the intergenic sequence between salicylate hydroxylase g ...19957794247
site-specific deletions of chromosomally located dna segments with the multimer resolution system of broad-host-range plasmid rp4.the multimer resolution system (mrs) of the broad-host-range plasmid rp4 has been exploited to develop a general method that permits the precise excision of chromosomal segments in a variety of gram-negative bacteria. the procedure is based on the site-specific recombination between two directly repeated 140-bp resolution (res) sequences of rp4 effected by the plasmid-borne resolvase encoded by the para gene. the efficiency and accuracy of the mrs system to delete portions of chromosomal dna fla ...19957798149
alginate regulatory and biosynthetic gene homologs in pseudomonas putida wcs358: correlation with the siderophore regulatory gene pfra.a previous study [venturi et al., mol. microbiol. 10 (1993) 63-73] demonstrated that the siderophore regulatory gene pfra of pseudomonas putida (pp) wcs358 is highly similar and interchangeable with the alginate regulatory gene algq (algr2) of p. aeruginosa (pa). the algq gene is physically linked to two other alginate regulators in the pa chromosome, namely algr (algr1), a response regulator, and algp (algr3), a histone-like gene. in this study, we have identified the same genes and a similar g ...19957698672
cloning and sequencing of a 29 kb region of the bacillus subtilis genome containing the hut and wapa loci.within the framework of an international project for the sequencing of the entire bacillus subtilis genome, a 29 kb chromosome segment, which contains the hut operon (335 degrees) and the wapa gene, has been cloned and sequenced. this region (28,954 bp) contains 21 complete orfs and one partial one. the 5th, 6th and 17th genes correspond to huth encoding histidase, hutp encoding the positive regulator for the hut operon and wapa encoding a precursor of three major wall-associated proteins, respe ...19957704263
cytological aspects of resistance to potassium tellurite conferred on pseudomonas cells by plasmids.the ultrastructure of strains pseudomonas putida bs228 and pseudomonas aeruginosa ml4262 harboring plasmids pbs10, pbs31, and pbs221, which determine resistance to potassium tellurite, was studied. bacteria were grown in media containing increasing concentrations of potassium tellurite. crystalline structures containing tellurium appeared in their periplasmic space. the dynamics of crystal growth was studied. crystals were released into the medium by pinching off of the outer membrane vesicles c ...19957763135
discontinuities in the evolution of pseudomonas putida cat genes.the organization and transcriptional control of chromosomal cat genes (required for dissimilation of catechol by the beta-ketoadipate pathway) in the pseudomonas putida biotype strain (atcc 12633) are reported. nucleotide sequence reveals that catr is separated by 135 bp from the divergently transcribed catbc,a; catc begins 21 nucleotides downstream from catb, and cata begins 41 nucleotides downstream from catc. this contrasts with the gene arrangement in other bacteria, in which cata lies sever ...19957814330
interesterification of butter fat by partially purified extracellular lipases from pseudomonas putida, aspergillus niger and rhizopus oryzae.three extracellular lipases were produced by batch fermentation of pseudomonas putida atcc 795, aspergillus niger cbs 131.52 and rhizopus oryzae atcc 34612 during the late phase of growth, at 72, 96 and 96 h, respectively. the lipases were partially purified by (nh4)2so4 fractionation. the lipase of p. putida was optimal at ph 8.0 whereas those from a. niger and r. oryzae were optimal at ph 7.5. the a. niger lipase had the lowest v max value (0.51×10(-3) u/min) and r. oryzae the highest (1.86×10 ...199524415019
modeling cytochrome p450 14 alpha demethylase (candida albicans) from p450cam.the tertiary structure of cytochrome p450 14 alpha demethylase--candida albicans (p450 ca) is modeled on the basis of sequence alignment with two closely related proteins and the crystallographic structure of pseudomonas putida p450cam. the secondary structure prediction system used combines the information from several algorithms and trains the data to offer an optimized prediction of the known p450cam. the trained algorithm was then used to predict the secondary structure of the other p450 seq ...19947819160
cloning and sequences of the first eight genes of the chromosomally encoded (methyl) phenol degradation pathway from pseudomonas putida p35x.pseudomonas putida p35x (ncib 9869) metabolises phenol and cresols via a chromosomally encoded meta-cleavage pathway. a 13.4-kb fragment of the chromosome involved in encoding phenol catabolism was cloned and characterized. deletion analysis and nucleotide sequencing of a 6589-bp region, in conjunction with enzyme assays, were used to identify the phhklmnop genes encoding the phenol hydroxylase, the phhb gene encoding catechol 2,3-dioxygenase (ec 1.13.11.2) and the phhq gene that encodes a small ...19947828892
cloning cassettes containing the reporter gene xyle.two puc-derived vectors containing the promoterless xyle gene (encoding catechol 2,3-dioxygenase) of pseudomonas putida mt-2 were constructed. the t(o) transcriptional terminator of phage lambda was placed downstream from the stop codon of xyle. the new vectors, pxt1 and pxt2, contain xyle and the t(o) terminator within a cloning cassette which can be excised with several endonucleases. when inserted into a transcribed sequence, this xyle cassette reports promoter activity and interrupts downstr ...19947828900
localization of functional domains in the escherichia coli coprogen receptor fhue and the pseudomonas putida ferric-pseudobactin 358 receptor pupa.transport of ferric-siderophores across the outer membrane of gram-negative bacteria is mediated by specific outer membrane receptors. to localize the substrate-binding domain of the ferric-pseudobactin 358 receptor, pupa, of pseudomonas putida wcs358, we constructed chimeric receptors in which different domains of pupa were replaced by the corresponding domains of the related ferric-pseudobactin receptors pupb and pupx, or the coprogen receptor fhue of escherichia coli. none of the chimeric pro ...19947830717
survival and impact of genetically engineered pseudomonas putida harboring mercury resistance gene in soil microcosms.the survival of genetically engineered and wild-type pseudomonas putida ppy101, that contained a recombinant plasmid psr134 conferring mercury resistance, were monitored in andosol and sand microcosms. the survival of genetically engineered and wild-type p. putida was not significantly different in andosol. the population change of the two strains was dissimilar in andosol and sand. the survival of genetically engineered and wild-type p. putida strains was affected by the water content of andoso ...19947764510
cloning and sequence analysis of a plasmid-encoded 2-haloacid dehalogenase gene from pseudomonas putida no. 109.the 2-haloacid dehalogenase of pseudomonas putida no. 109 was mediated by a 74-kb conjugative plasmid, which was transferred by mating into pseudomonas and escherichia coli and there expressed the dehalogenase. a 2.8-kb ecori-fragment generated from the plasmid was cloned and sequenced. the dehalogenase gene (dehh109) was identified by comparison with the n-terminal amino acid sequence and the molecular weight of the enzyme protein. the gene dehh109 coded for a 224-amino acid protein of m(r) 25, ...19947764511
transformation of pseudomonas putida by electroporation.the optimum electrotransformation conditions were determined for pseudomonas putida ppy101 with plasmid psup104 (9.5 kb) and psr134 (18.6 kb). field strength was a very important parameter for electrotransformation efficiency. optimum efficiencies (1.1 x 10(5) transformants/micrograms dna) with psup104 and psr134 were obtained at a field strength of 12.5 kv/cm, a time constant of about 4.5 ms (resistance setting of 200 ohms), a supercoiled dna concentration of 100 ng/ml, and a cell concentration ...19947764975
tol plasmid-specified xylene oxygenase is a wide substrate range monooxygenase capable of olefin epoxidation.xylene oxygenase, which is encoded on the tol plasmid pwwo of pseudomonas putida mt-2, is a key enzyme system in the degradation of toluene and xylenes by this organism. it was expressed in an escherichia coli recombinant strain carrying the xylma structural genes. this recombinant, which expressed xylene oxygenase from the heat-shock induced lambda pl promoter, was analyzed for its potential as a biocatalytic tool so as to effect the oxidation of side chains of aromatic hydrocarbons to the corr ...19947764991
production, partial characterization, and potential diagnostic use of salicylate hydroxylase from pseudomonas putida uuc-1.an unusual strain of pseudomonas putida uuc-1 capable of growth at high salicylate concentration (10 gl-1) was investigated with the aim of developing an assay and a biosensor system for determining salicylate in body fluids by utilizing the salicylate hydroxylase enzyme. medium and growth condition optimization were carried out under chemostat conditions. the highest biomass yield was at 4.0 gl-1 salicylate, 25 degrees c, ph 6.5, and 0.2 h-1 dilution rate. growth occurred at up to 0.45 h-1 dilu ...19947765077
characterization of phe b gene encoding catechol 2,3-dioxygenase.dna sequence of the phe b gene isolated from a chromosome of the phenol degrading bacterium pseudomonas putida bh is identical to that of the dmp b gene from the phenol degradative plasmid, pvi150. catechol 2,3-dioxygenase encoded by phe b showed similar substrate specificity to that of xyl e. however, phe b has much smaller km values than xyl e, indicating that phe b is useful for treatment of low concentrations of catechol derivatives in waste water.19947765392
cloning and expression of pseudomonas putida esterase gene in escherichia coli and its use in enzymatic production of d-beta-acetylthioisobutyric acid.the esterase catalyzes the stereoselective hydrolysis of methyl dl-beta-acetylthioisobutyrate (dl-ester) to give d-beta-acetylthioisobutyric acid (dat). to use the enzyme for dat production, the esterase gene of pseudomonas putida was cloned and expressed in e. coli. the recombinant e. coli containing the esterase gene produced a large amount of the enzyme in an active form. this strain could be used for the asymmetric synthesis of dat.19947765492
degradation of methyl parathion by pseudomonas putida.pseudomonas putida utilized methyl parathion as sole carbon and (or) phosphorus source. the bacterium elaborated the enzyme organophosphorus acid anhydrase, which hydrolyzed methyl parathion to p-nitrophenol. p-nitrophenol was further degraded to hydroquinone and 1,2,4-benzenetriol. the final ring compound, 1,2,4-benzenetriol, was cleaved by benzenetriol oxygenase to maleyl acetate.19947704828
nucleotide sequence and functional analysis of the genes encoding 2,4,5-trichlorophenoxyacetic acid oxygenase in pseudomonas cepacia ac1100.pseudomonas cepacia ac1100 is able to use the chlorinated aromatic compound 2,4,5-trichlorophenoxyacetic acid (2,4,5-t) as the sole source of carbon and energy. one of the early steps in this pathway is the conversion of 2,4,5-t to 2,4,5-trichlorophenol (2,4,5-tcp). 2,4,5-tcp accumulates in the culture medium when ac1100 is grown in the presence of 2,4,5-t. a dna region from the ac1100 genome has been subcloned as a 2.7-kb ssti-xbai dna fragment, which on transfer to pseudomonas aeruginosa pao1 ...19947527626
interaction of two lysr-type regulatory proteins catr and clcr with heterologous promoters: functional and evolutionary implications.the soil bacteria pseudomonas putida can use benzoate or 3-chlorobenzoate as a sole carbon source. benzoate and 3-chlorobenzoate are converted into catechol and 3-chlorocatechol, respectively, which are in turn converted into tricarboxylic acid cycle intermediates. the catabolic pathways of both compounds proceed through similar intermediates, have similar genetic organization, and have homologous enzymes responsible for different catabolic steps. this has led to suggestions that the plasmid-bor ...19947809047
adaptation of pseudomonas putida s12 to ethanol and toluene at the level of fatty acid composition of membranes.pseudomonas putida s12 was more tolerant to ethanol when preadapted to supersaturating concentrations of toluene. cellular reactions at the membrane level to the toxicities of both compounds were different. in growing cells of p. putida s12, sublethal concentrations of toluene resulted in an increase in the degree of saturation of the membrane fatty acids, whereas toxically equivalent concentrations of ethanol led to a decrease in this value. contrary to this, cells also reacted to both substanc ...19947811084
trichloroethylene removal and oxidation toxicity mediated by toluene dioxygenase of pseudomonas putida.whole cells of pseudomonas putida containing toluene dioxygenase were able to remove all detectable trichloroethylene (tce) from assay mixtures. the capacity of cells to remove tce was 77 microm/mg of protein with an initial rate of removal of 5.2 nmol/min/ng of protein. tce oxidation resulted in a decrease in the growth rate of cultures and caused rapid cell death. addition of dithiothreitol to assay mixtures increased the tce removal capacity of cells by up to 67% but did not prevent tce-media ...19947811103
Refresh
firstprev
...919293949596979899100...
nextlast
Displaying items 9901 - 10000 of 11585