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biodegradation of 4-methyl-5-nitrocatechol by pseudomonas sp. strain dnt.pseudomonas sp. strain dnt degrades 2,4-dinitrotoluene (dnt) by a dioxygenase attack at the 4,5 position with concomitant removal of the nitro group to yield 4-methyl-5-nitrocatechol (mnc). here we describe the mechanism of removal of the nitro group from mnc and subsequent reactions leading to ring fission. washed suspensions of dnt-grown cells oxidized mnc and 2,4,5-trihydroxytoluene (tht). extracts prepared from dnt-induced cells catalyzed the disappearance of mnc in the presence of oxygen an ...19948195105
pseudomonas sp. strain hbp1 prp degrades 2-isopropylphenol (ortho-cumenol) via meta cleavage.pseudomonas sp. strain hbp1 prp grew on 2-isopropylphenol as the sole carbon and energy source with a maximal specific growth rate of 0.14 h-1 and transient accumulation of isobutyric acid. oxygen uptake experiments with resting cells and enzyme assays with crude-cell extracts showed that 2-isopropylphenol was catabolized via a broad-spectrum meta cleavage pathway. these findings were confirmed by experiments with partially purified enzymes. identification of 3-isopropylcatechol and 2-hydroxy-6- ...19947811094
use of molecular techniques to evaluate the survival of a microorganism injected into an aquifer.a pcr primer set and an internal probe that are specific for pseudomonas sp. strain b13, a 3-chlorobenzoate-metabolizing strain, were developed. using this primer set and probe, we were able to detect pseudomonas sp. strain b13 dna sequences in dna extracted from aquifer samples 14.5 months after pseudomonas sp. strain b13 had been injected into a sand and gravel aquifer. this primer set and probe were also used to analyze isolates from 3-chlorobenzoate enrichments of the aquifer samples by sout ...19947912498
regiospecific and stereoselective hydroxylation of 1-indanone and 2-indanone by naphthalene dioxygenase and toluene dioxygenase.the biotransformation of 1-indanone and 2-indanone to hydroxyindanones was examined with bacterial strains expressing naphthalene dioxygenase (ndo) and toluene dioxygenase (tdo) as well as with purified enzyme components. pseudomonas sp. strain 9816/11 cells, expressing ndo, oxidized 1-indanone to a mixture of 3-hydroxy-1-indanone (91%) and 2-hydroxy-1-indanone (9%). the (r)-3-hydroxy-1-indanone was formed in 62% enantiomeric excess (ee) (r:s, 81:19), while the 2-hydroxy-1-indanone was racemic. ...19947944365
comparative studies of genes encoding thermostable l-2-halo acid dehalogenase from pseudomonas sp. strain yl, other dehalogenases, and two related hypothetical proteins from escherichia coli.we have determined the nucleotide sequence of the gene encoding thermostable l-2-halo acid dehalogenase (l-dex) from the 2-chloroacrylate-utilizable bacterium pseudomonas sp. strain yl. the open reading frame consists of 696 nucleotides corresponding to 232 amino acid residues. the protein molecular weight was estimated to be 26,179, which was in good agreement with the subunit molecular weight of the enzyme. the gene was efficiently expressed in the recombinant escherichia coli cells: the amoun ...19947944368
biodegradation of 2-nitrotoluene by pseudomonas sp. strain js42.a strain of pseudomonas sp. was isolated from nitrobenzene-contaminated soil and groundwater on 2-nitrotoluene as the sole source of carbon, energy, and nitrogen. bacterial cells growing on 2-nitrotoluene released nitrite into the growth medium. the isolate also grew on 3-methylcatechol, 4-methylcatechol, and catechol. 2-nitrotoluene, 3-methylcatechol, and catechol stimulated oxygen consumption by intact cells regardless of the growth substrate. crude extracts from the isolate contained catechol ...19947944378
initial reactions in the anaerobic oxidation of toluene and m-xylene by denitrifying bacteria.pseudomonas sp. strain t and pseudomonas sp. strain k172 grow with toluene under denitrifying conditions. we demonstrated that anaerobic degradation of toluene was initiated by direct oxidation of the methyl group. benzaldehyde and benzoate accumulated sequentially after toluene was added when cell suspensions were incubated at 5 degrees c. strain t also grows anaerobically with m-xylene, and we demonstrated that degradation was initiated by oxidation of one methyl group. in cell suspensions inc ...19947993091
oxidative release of nitrite from 2-nitrotoluene by a three-component enzyme system from pseudomonas sp. strain js42.pseudomonas sp. strain js42 utilizes 2-nitrotoluene (2nt) as the sole source of carbon and energy for growth. intact cells catalyze the oxidation of 2nt to 3-methylcatechol and nitrite in a reaction that requires molecular oxygen. cell extracts oxidized 2nt to 3-methylcatechol and nitrite in the presence of nad(p)h and ferrous iron. ion-exchange chromatography yielded three protein fractions (a, b, and c) which were all required for the oxidation of 2nt to 3-methylcatechol and nitrite. component ...19948002568
an aromatic effector specificity mutant of the transcriptional regulator dmpr overcomes the growth constraints of pseudomonas sp. strain cf600 on para-substituted methylphenols.the pvi150 catabolic plasmid of pseudomonas sp. strain cf600 carries the dmp system, which comprises the divergently transcribed dmpr gene and the dmp operon coding for the catabolic enzymes required for growth on (methyl)phenols. the constitutively expressed dmpr transcriptional activator positively controls the expression of the rpon-dependent dmp operon promoter in the presence of the aromatic effector in the growth medium. however, the magnitude of the transcriptional response differs depend ...19948002579
organization and evolution of naphthalene catabolic pathways: sequence of the dna encoding 2-hydroxychromene-2-carboxylate isomerase and trans-o-hydroxybenzylidenepyruvate hydratase-aldolase from the nah7 plasmid.the sequence of a 2,437-bp dna segment from the naphthalene upper catabolic pathway operon of plasmid nah7 was determined. this segment contains three large open reading frames designated nahq', nahe, and nahd. the first of these is the 3' end of an open reading frame that has no known function, the second (993 bp) encodes trans-o-hydroxybenzylidenepyruvate hydratase-aldolase (deduced molecular weight, 36,640), and the third (609 bp) encodes 2-hydroxychromene-2-carboxylate isomerase (deduced mol ...19948002605
a biological sensor for iron available to bacteria in their habitats on plant surfaces.a sensor responsive to iron was constructed by fusing a promoterless ice nucleation activity gene (inaz) to an iron-regulated promoter of a genomic region involved in pyoverdine (fluorescent siderophore) (pvd) production in pseudomonas syringae. cells of pseudomonas fluorescens and p. syringae that contained the pvd-inaz fusion expressed iron-responsive ice nucleation activity in the bean rhizosphere and phyllosphere, respectively, and in culture. addition of fe(iii) to leaves or soil reduced th ...199416349283
quantification of frankia strains and other root-associated bacteria in pure cultures and in the rhizosphere of axenic seedlings by high-performance liquid chromatography-based muramic acid assay.application of a high-performance liquid chromatography-based muramic acid assay with precolumn fluorescence derivatization to quantification of root-associated bacteria was studied both in pure cultures and in the rhizosphere of axenic festuca rubra seedlings. quantities of muramic acid from acid-hydrolyzed cells of frankia strains, streptomyces griseoviridis, enterobacter agglomerans, klebsiella pneumoniae, pseudomonas sp., and bacillus polymyxa were mostly proportional to the respective cell ...199416349413
kinetics of bacterial growth on chlorinated aliphatic compounds.with the pure bacterial cultures ancylobacter aquaticus ad20 and ad25, xanthobacter autotrophicus gj10, and pseudomonas sp. strain ad1, monod kinetics was observed during growth in chemostat cultures on 1,2-dichloroethane (ad20, ad25, and gj10), 2-chloroethanol (ad20 and gj10), and 1,3-dichloro-2-propanol (ad1). both the michaelis-menten constants (k(m)) of the first catabolic (dehalogenating) enzyme and the monod half-saturation constants (k(s)) followed the order 2-chloroethanol, 1,3-dichloro- ...199316348981
cloning, sequence analysis, and expression of the flavobacterium pentachlorophenol-4-monooxygenase gene in escherichia coli.the pcpb gene of flavobacterium sp. strain atcc 39723 was cloned by using a degenerate primer designed from the n-terminal sequence of the purified enzyme. the nucleotide sequence of pcpb was determined and found to encode an open reading frame of 1,614 nucleotides, yielding a predicted translation product of 538 amino acids, in agreement with the estimated size of the purified protein analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. the transcriptional start of pcpb was fo ...19937678243
influence of organic nutrients and cocultures on the competitive behavior of 1,2-dichloroethane-degrading bacteria.the effects of organic nutrients and cocultures on substrate removal by and competitive behavior of 1,2-dichloroethane-degrading bacteria were investigated. xanthobacter autotrophicus gj10 needed biotin for optimal growth on 1,2-dichloroethane. in continuous culture, dilution of biotin to a concentration below 0.2 nm resulted in washout. growth could be restored by inoculation with the 2-chloroethanol utilizer pseudomonas sp. strain gj1, leading to a new steady state in which about 1% of the mix ...19938250561
identification of a major soluble protein in mitochondria from nonphotosynthetic tissues as nad-dependent formate dehydrogenase.in many plant species, one of the most abundant soluble proteins (as judged by two-dimensional polyacrylamide gel electrophoresis) in mitochondria from nongreen tissues is a 40-kd polypeptide that is relatively scarce in mitochondria from photosynthetic tissues. cdna sequences encoding this polypeptide were isolated from a lambda gt11 cdna expression library from potato (solanum tuberosum l.) by screening with a specific antibody raised against the 40-kd polypeptide. the cdna sequence contains a ...19938278546
enhanced biodegradation of polychlorinated biphenyls after site-directed mutagenesis of a biphenyl dioxygenase gene.biphenyl dioxygenase catalyzes the first step in the aerobic degradation of polychlorinated biphenyls (pcbs). the nucleotide and amino acid sequences of the biphenyl dioxygenases from two pcb-degrading strains (pseudomonas sp. strain lb400 and pseudomonas pseudoalcaligenes kf707) were compared. the sequences were found to be nearly identical, yet these enzymes exhibited dramatically different substrate specificities for pcbs. site-directed mutagenesis of the lb400 bpha gene resulted in an enzyme ...19938285689
detection of polychlorinated biphenyl degradation genes in polluted sediments by direct dna extraction and polymerase chain reaction.it was the aim of this study to specifically detect the dna sequences for the bphc gene, the meta-cleavage enzyme of the aerobic catabolic pathway for biphenyl and polychlorinated biphenyl degradation, in aquatic sediments without prior cultivation of microorganisms by using extraction of total dna, pcr amplification of bphc sequences, and detection with specific gene probes. the direct dna extraction protocol used was modified to enhance lysis efficiency. crude extracts of dna were further puri ...19938285706
development of field application vectors for bioremediation of soils contaminated with polychlorinated biphenyls.field application vectors (favs), which are a combination of a selective substrate, a host, and a cloning vector, have been developed for the purpose of expressing foreign genes in nonsterile, competitive environments in which the gene products provide no advantage to the host. such gene products are exemplified by the enzymes for the cometabolism of polychlorinated biphenyls (pcbs) through the biphenyl degradation pathway. attempts to use highly competent pcb-cometabolizing strains in the envir ...19938328798
oxidation of polychlorinated biphenyls by pseudomonas sp. strain lb400 and pseudomonas pseudoalcaligenes kf707.biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of pseudomonas sp. strain lb400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from pseudomonas pseudoalcaligenes kf707. these results are attributed to differences in the substrate specificity of the biphenyl 2,3-dioxygenases from both organisms.19938331086
new aerobic benzoate oxidation pathway via benzoyl-coenzyme a and 3-hydroxybenzoyl-coenzyme a in a denitrifying pseudomonas sp.a denitrifying pseudomonas sp. is able to oxidize aromatic compounds compounds completely to co2, both aerobically and anaerobically. it is shown that benzoate is aerobically oxidized by a new degradation pathway via benzoyl-coenzyme a (coa) and 3-hydroxybenzoyl-coa. the organism grew aerobically with benzoate, 3-hydroxybenzoate, and gentisate; catechol, 2-hydroxybenzoate, and protocatechuate were not used, and 4-hydroxybenzoate was a poor substrate. mutants were obtained which were not able to ...19938335640
effects of medium and trace metals on kinetics of carbon tetrachloride transformation by pseudomonas sp. strain kc.under denitrifying conditions, pseudomonas sp. strain kc transforms carbon tetrachloride (ct) to carbon dioxide via a complex but as yet undetermined mechanism. transformation rates were first order with respect to ct concentration over the ct concentration range examined (0 to 100 micrograms/liter) and proportional to protein concentration, giving pseudo-second-order kinetics overall. addition of ferric iron (1 to 20 microm) to an actively transforming culture inhibited ct transformation, and t ...19938357248
biodegradation of 4-nitrotoluene by pseudomonas sp. strain 4nt.a strain of pseudomonas spp. was isolated from nitrobenzene-contaminated soil on 4-nitrotoluene as the sole source of carbon, nitrogen, and energy. the organism also grew on 4-nitrobenzaldehyde, and 4-nitrobenzoate. 4-nitrobenzoate and ammonia were detected in the culture fluid of glucose-grown cells after induction with 4-nitrotoluene. washed suspensions of 4-nitrotoluene- or 4-nitrobenzoate-grown cells oxidized 4-nitrotoluene, 4-nitrobenzaldehyde, 4-nitrobenzyl alcohol, and protocatechuate. ex ...19938357257
degradation of chloroaromatics: purification and characterization of maleylacetate reductase from pseudomonas sp. strain b13.maleylacetate reductase of pseudomonas sp. strain b13 was purified to homogeneity by chromatography on deae-cellulose, butyl-sepharose, blue-sepharose, and sephacryl s100. the final preparation gave a single band by polyacrylamide gel electrophoresis under denaturing conditions and a single symmetrical peak by gel filtration under nondenaturing conditions. the subunit m(r) value was 37,000 (determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis). estimation of the native m(r) va ...19938407778
purification and properties of the physically associated meta-cleavage pathway enzymes 4-hydroxy-2-ketovalerate aldolase and aldehyde dehydrogenase (acylating) from pseudomonas sp. strain cf600.the final two steps in the dmp operon-encoded meta-cleavage pathway for phenol degradation in pseudomonas sp. strain cf600 involve conversion of 4-hydroxy-2-ketovalerate to pyruvate and acetyl coenzyme a (acetyl-coa) by the enzymes 4-hydroxy-2-ketovalerate aldolase and aldehyde dehydrogenase (acylating) [acetaldehyde:nad+ oxidoreductase (coa acetylating), ec 1.2.1.10]. a procedure for purifying these two enzyme activities to homogeneity is reported here. the two activities were found to copurify ...19938419288
oxidation of biphenyl by a multicomponent enzyme system from pseudomonas sp. strain lb400.pseudomonas sp. strain lb400 grows on biphenyl as the sole carbon and energy source. this organism also cooxidizes several chlorinated biphenyl congeners. biphenyl dioxygenase activity in cell extract required addition of nad(p)h as an electron donor for the conversion of biphenyl to cis-2,3-dihydroxy-2,3-dihydrobiphenyl. incorporation of both atoms of molecular oxygen into the substrate was shown with 18o2. the nonlinear relationship between enzyme activity and protein concentration suggested t ...19938419290
degradation of 2-chloroallylalcohol by a pseudomonas sp.three pseudomonas strains capable of utilizing 2-chloroallylalcohol (2-chloropropenol) as the sole carbon source for growth were isolated from soil. the fastest growth was observed with strain jd2, with a generation time of 3.6 h. degradation of 2-chloroallylalcohol was accompanied by complete dehalogenation. chloroallylalcohols that did not support growth were dechlorinated by resting cells; the dechlorination level was highest if an alpha-chlorine substituent was present. crude extracts of str ...19938434917
characterization of the structural gene encoding a copper-containing nitrite reductase and homology of this gene to dna of other denitrifiers.a copper-containing nitrite reductase gene (niru) from pseudomonas sp. strain g-179 was found in a 1.9-kb ecori-bamhi dna fragment. the coding region contained information for a polypeptide of 379 amino acids. the encoded protein had 78% identity in amino acid sequence to the nitrite reductase purified from achromobacter cycloclastes. the ligands for type 1 copper- and type 2 copper-binding sites found in a. cycloclastes were also found in pseudomonas sp. strain g-179, suggesting that these bind ...19938439151
cloning and nucleotide sequence of the gene encoding the positive regulator (dmpr) of the phenol catabolic pathway encoded by pvi150 and identification of dmpr as a member of the ntrc family of transcriptional activators.the catabolic plasmid pvi150 of pseudomonas sp. strain cf600 encodes all the genetic information required for the regulated metabolism of phenol and some of its methyl-substituted derivatives. the structural dmp genes of the pathway are clustered in a single operon that lies just downstream of a -24 tggc, -12 ttgc nif/ntr-like promoter sequence. promoters of this class are recognized by a minor form of rna polymerase utilizing sigma 54 (ntra, rpon). primer extension analysis demonstrated that th ...19938449869
metabolism of 2,2'-dihydroxybiphenyl by pseudomonas sp. strain hbp1: production and consumption of 2,2',3-trihydroxybiphenyl.cells of pseudomonas sp. strain hbp1 grown on 2-hydroxy- or 2,2'-dihydroxybiphenyl contain nadh-dependent monooxygenase activity that hydroxylates 2,2'-dihydroxybiphenyl. the product of this reaction was identified as 2,2',3-trihydroxybiphenyl by 1h nuclear magnetic resonance and mass spectrometry. furthermore, the monooxygenase activity also hydroxylates 2,2',3-trihydroxybiphenyl at the c-3' position, yielding 2,2',3,3'-tetrahydroxybiphenyl as a product. an estradiol ring cleavage dioxygenase a ...19938449871
cloning and characterization of pseudomonas sp. strain dnt genes for 2,4-dinitrotoluene degradation.the degradation of 2,4-dinitrotoluene (dnt) by pseudomonas sp. strain dnt is initiated by a dioxygenase attack to yield 4-methyl-5-nitrocatechol (mnc) and nitrite. subsequent oxidation of mnc by a monooxygenase results in the removal of the second molecule of nitrite, and further enzymatic reactions lead to ring fission. initial studies on the molecular basis of dnt degradation in this strain revealed the presence of three plasmids. mitomycin-derived mutants deficient in either dnt dioxygenase o ...19938449889
construction of a pseudomonas hybrid strain that mineralizes 2,4,6-trinitrotoluene.a bacterium, pseudomonas sp. strain c1s1, able to grow on 2,4,6-trinitrotoluene (tnt), 2,4- and 2,6-dinitrotoluene, and 2-nitrotoluene as n sources, was isolated. the bacterium grew at 30 degrees c with fructose as a c source and accumulated nitrite. through batch culture enrichment, we isolated a derivative strain, called pseudomonas sp. clone a, which grew faster on tnt and did not accumulate nitrite in the culture medium. use of tnt by these two strains as an n source involved the successive ...19938468288
selection of pseudomonas sp. strain hbp1 prp for metabolism of 2-propylphenol and elucidation of the degradative pathway.a mutant of pseudomonas sp. strain hbp1, originally isolated on 2-hydroxybiphenyl, was selected for the ability to grow on 2-propylphenol as the sole carbon and energy source. in the mutant strain, which was designated as pseudomonas sp. strain hbp1 prp, the cellular induction mechanism involved in the synthesis of the nadh-dependent monooxygenase is changed. 2-propylphenol, which is known to be a substrate of the monooxygenase, does not induce formation of the monooxygenase in the wild type but ...19938481010
n.m.r. spectroscopic studies of fucose-containing oligosaccharides derived from keratanase digestion of articular cartilage keratan sulphates. influence of fucose residues on keratanase cleavage.keratan sulphate chains from bovine articular cartilage were fully digested with keratanase from pseudomonas sp. and the products were reduced with alkaline borohydride. the resultant fragments were fractionated on a nucleosil 5sb column and the earliest eluting fucose-containing oligosaccharides were isolated. structural analysis using 1h n.m.r. spectroscopy (600 mhz) showed the two least-charged species to have the following structure: glcnac(6s) beta 1-3gal beta 1-4(fuc alpha 1-3)glcnac(6s) b ...19938489515
developmental regulation of the gene for formate dehydrogenase in neurospora crassa.we have isolated and characterized a gene, fdh, from neurospora crassa which is developmentally regulated and which produces formate dehydrogenase activity when expressed in escherichia coli. the gene is closely linked (less than 0.6 kb apart) to the leu-5 gene encoding mitochondrial leucyl-trna synthetase; the two genes are transcribed convergently from opposite strands. the expression patterns of these genes differ: fdh mrna is found only during conidiation and early germination and is not det ...19938509325
microbial oxidation of dimethylnaphthalene isomers.three bacterial strains, identified as alcaligenes sp. strain d-59 and pseudomonas sp. strains d-87 and d-186, capable of growing on 2,6-dimethylnaphthalene (2,6-dmn) as the sole source of carbon and energy were isolated from soil samples. 2,6-naphthalene dicarboxylic acid was formed in the culture broths of these three strains grown on 2,6-dmn. in addition, 2-hydroxymethyl-6-methylnaphthalene and 6-methylnaphthalene-2-carboxylic acid were detected in the culture broth of strain d-87. strain d-8 ...19938517744
physiological factors affecting carbon tetrachloride dehalogenation by the denitrifying bacterium pseudomonas sp. strain kc.pseudomonas sp. strain kc was grown on a medium with a low content of transition metals in order to examine the conditions for carbon tetrachloride (ct) transformation. several carbon sources, including acetate, glucose, glycerol, and glutamate, were able to support ct transformation. the chelators 2,2'-dipyridyl and 1,10-phenanthroline stimulated ct transformation in a rich medium that otherwise did not support this activity. low (< 10 microm) additions of dissolved iron(ii), iron(iii), and cob ...19938517754
nucleotide sequence and functional analysis of the complete phenol/3,4-dimethylphenol catabolic pathway of pseudomonas sp. strain cf600.the meta-cleavage pathway for catechol is one of the major routes for the microbial degradation of aromatic compounds. pseudomonas sp. strain cf600 grows efficiently on phenol, cresols, and 3,4-dimethylphenol via a plasmid-encoded multicomponent phenol hydroxylase and a subsequent meta-cleavage pathway. the genes for the entire pathway were previously found to be clustered, and the nucleotide sequences of dmpklmnopbc and d, which encode the first four biochemical steps of the pathway, were deter ...19921732207
cloning and sequencing of the genes involved in the conversion of 5-substituted hydantoins to the corresponding l-amino acids from the native plasmid of pseudomonas sp. strain ns671.pseudomonas sp. strain ns671, which produces l-amino acids asymmetrically from the corresponding racemic 5-substituted hydantoins, harbored a plasmid of 172 kb. curing experiments suggest that this plasmid, designated phn671, is responsible for the conversion of 5-substituted hydantoins to their corresponding l-amino acids by strain ns671. dna fragments containing the genes involved in this conversion were cloned from phn671 in escherichia coli by using puc18 as a cloning vector. the smallest re ...19921732229
characterization of tn5 mutants deficient in dissimilatory nitrite reduction in pseudomonas sp. strain g-179, which contains a copper nitrite reductase.tn5 was used to generate mutants that were deficient in the dissimilatory reduction of nitrite for pseudomonas sp. strain g-179, which contains a copper nitrite reductase. three types of mutants were isolated. the first type showed a lack of growth on nitrate, nitrite, and nitrous oxide. the second type grew on nitrate and nitrous oxide but not on nitrite (nir-). the two mutants of this type accumulated nitrite, showed no nitrite reductase activity, and had no detectable nitrite reductase protei ...19921328160
identification and sequencing of a gene encoding a hydantoin racemase from the native plasmid of pseudomonas sp. strain ns671.dna fragments containing the genes involved in the conversion of 5-substituted hydantoins to their corresponding l-amino acids have been cloned from the 172-kb native plasmid (phn671) of pseudomonas sp. strain ns671. the largest recombinant plasmid, designated phpb14, encoded the ability to convert d-5-substituted hydantoins to the corresponding l-amino acids, whereas the smallest one, designated phpb12, encoded the ability to convert them to their corresponding n-carbamyl-d-amino acids. restric ...19921339422
expression and transfer of engineered catabolic pathways harbored by pseudomonas spp. introduced into activated sludge microcosms.two genetically engineered microorganisms (gems), pseudomonas sp. strain b13 fr1(pfrc20p) (fr120) and pseudomonas putida kt2440(pwwo-eb62) (eb62), were introduced into activated sludge microcosms that had the level of aeration, nutrient makeup, and microbial community structure of activated sludge reactors. fr120 contains an experimentally assembled ortho cleavage route for simultaneous degradation of 3-chlorobenzoate (3cb) and 4-methyl benzoate (4mb); eb62 contains a derivative tol plasmid-enco ...19921444370
characterization of a novel pseudomonas sp. that mineralizes high concentrations of pentachlorophenol.a pentachlorophenol (pcp)-mineralizing bacterium was isolated from polluted soil and identified as pseudomonas sp. strain ra2. in batch cultures, pseudomonas sp. strain ra2 used pcp as its sole source of carbon and energy and was capable of completely degrading this compound as indicated by radiotracer studies, stoichiometric release of chloride, and biomass formation. pseudomonas sp. strain ra2 was able to mineralize a higher concentration of pcp (160 mg liter-1) than any previously reported pc ...19921444401
metabolism of hexadecyltrimethylammonium chloride in pseudomonas strain b1.a bacterium (strain b1) utilizing hexadecyltrimethylammonium chloride as a carbon and energy source was isolated from activated sludge and tentatively identified as a pseudomonas sp. this bacterium only grew on alkyltrimethylammonium salts (c12 to c22) and possible intermediates of hexadecyltrimethylammonium chloride breakdown such as hexadecanoate and acetate. pseudomonas strain b1 did not grow on amines. simultaneous adaptation studies suggested that the bacterium oxidized only the alkyl chain ...19921444422
purification and characterization of the hydantoin racemase of pseudomonas sp. strain ns671 expressed in escherichia coli.the hydantoin racemase gene of pseudomonas sp. strain ns671 had been cloned and expressed in escherichia coli. hydantoin racemase was purified from the cell extract of the e. coli strain by phenyl-sepharose, deae-sephacel, and sephadex g-200 chromatographies. the purified enzyme had an apparent molecular mass of 32 kda as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. by gel filtration, a molecular mass of about 190 kda was found, suggesting that the native enzyme is a ...19921459947
exploitation of gene(s) involved in 2,4-diacetylphloroglucinol biosynthesis to confer a new biocontrol capability to a pseudomonas strain.tn5 mutagenesis and complementation analysis were used to clone a 6-kb genomic fragment required for biosynthesis of 2,4-diacetylphloroglucinol (phl) from fluorescent pseudomonas sp. strain f113. a recombinant plasmid, pcu203, containing this region partially complemented a phl production-negative mutant (f113g22) derived from strain f113. when sugar beet seeds were sown into an unsterilized soil, in which sugar beet was subject to damping-off by pythium ultimum, the emergence of sugar beet seed ...19921476431
cloning and sequence analysis of genes for dehalogenation of 4-chlorobenzoate from arthrobacter sp. strain su.strains of arthrobacter catalyze a hydrolytic dehalogenation of 4-chlorobenzoate (4-cba) to p-hydroxybenzoate. the reaction requires atp and coenzyme a (coa), indicating activation of the substrate via a thioester, like that reported for pseudomonas sp. strain cbs3 (j. d. scholten, k.-h. chang, p. c. babbit, h. charest, m. sylvestre, and d. dunaway-mariano, science 253:182-185, 1991). the dehalogenase genes of arthrobacter sp. strain su were cloned and expressed in escherichia coli. analyses of ...19921476446
oxidation of nitrotoluenes by toluene dioxygenase: evidence for a monooxygenase reaction.pseudomonas putida f1 and pseudomonas sp. strain js150 initiate toluene degradation by incorporating molecular oxygen into the aromatic nucleus to form cis-1,2-dihydroxy-3-methylcyclohexa-3,5-diene. when toluene-grown cells were incubated with 2- and 3-nitrotoluene, the major products identified were 2- and 3-nitrobenzyl alcohol, respectively. the same cells oxidized 4-nitrotoluene to 2-methyl-5-nitrophenol and 3-methyl-6-nitrocatechol. escherichia coli jm109(pdtg601), which contains the toluene ...19921514810
structural and biochemical characterization of the escherichia coli arge gene product.the dna sequence of a 2,100-bp region containing the arge gene from escherichia coli has been determined. the nucleotide sequence of the ppc-arge intergenic region was also solved and shown to contain six tandemly repeated rep sequences. moreover, the oxyr gene has been mapped on the e. coli chromosome and shown to flank the arg operon. the codon responsible for the translation start of arge was determined by using site-directed mutants. this gene spans 1,400 bp and encodes a 42,350-da polypepti ...19921551850
bacterial metabolism of 5-aminosalicylic acid. initial ring cleavage.the metabolism of 5-aminosalicylate (5as) by a bacterial strain, pseudomonas sp. bn9, was studied. intact cells of pseudomonas sp. bn9 grown with 5as oxidized 5as and 2,5-dihydroxybenzoate (gentisate), whereas cells grown with gentisate oxidized only the growth substrate of all substituted salicylates tested. cell extracts from pseudomonas sp. bn9 catalysed the stoichiometric reaction of 1 mol of oxygen with 1 mol of 5as to a metabolite with an intense u.v.-absorption maximum at 352 nm (ph 8.0). ...19921554350
cloning and partial sequencing of an operon encoding two pseudomonas putida haloalkanoate dehalogenases of opposite stereospecificity.we have cloned fragments of dna (up to 13 kb), from pseudomonas putida aj1, that code for two stereospecific haloalkanoate dehalogenases. these enzymes are highly specific for d and l substrates. the two genes, designated hadd and hadl, have been isolated and independently expressed in escherichia coli and p. putida hosts by using broad-host-range vectors. they are closely adjacent and inducible in what appears to be an operon with an upstream open reading frame of unknown function. nucleotide s ...19921556080
anaerobic degradation of 2-aminobenzoic acid (anthranilic acid) via benzoyl-coenzyme a (coa) and cyclohex-1-enecarboxyl-coa in a denitrifying bacterium.the enzymes catalyzing the initial reactions in the anaerobic degradation of 2-aminobenzoic acid (anthranilic acid) were studied with a denitrifying pseudomonas sp. anaerobically grown with 2-aminobenzoate and nitrate as the sole carbon and energy sources. cells grown on 2-aminobenzoate are simultaneously adapted to growth with benzoate, whereas cells grown on benzoate degrade 2-aminobenzoate several times less efficiently than benzoate. evidence for a new reductive pathway of aromatic metabolis ...19921592816
evaluation of aquatic sediment microcosms and their use in assessing possible effects of introduced microorganisms on ecosystem parameters.in this paper we describe a sediment microcosm system consisting of 20 undisturbed, layered sediment cores with overlying site water which are incubated under identical conditions of temperature, light, stirring rate of overlying water, and water exchange rate. ecosystem parameters (nutrient level, photosynthetic potential, community structure of heterotrophic bacteria, thymidine incorporation rate, and oxygen microgradients) of the laboratory microcosms and the source ecosystem were compared an ...19921599244
survival and function of a genetically engineered pseudomonad in aquatic sediment microcosms.pseudomonas sp. strain b13 fr1(pfrc20p) is a genetically engineered microorganism (gem) which is able to degrade chloro- and methylaromatics through a constructed ortho cleavage pathway. the fate of the gem and its ability to degrade substituted aromatic compounds in two different aquatic sediments was investigated by using a microcosm system which consisted of intact layered sediment cores with an overlying water column. the gem survived in lake plussee and in rhine river sediments at densities ...19921599245
construction of a 3-chlorobiphenyl-utilizing recombinant from an intergeneric mating.recombinant pseudomonas sp. strain cb15, which grows on 3-chlorobiphenyl (3cb), was constructed from pseudomonas sp. strain hf1, which grows on 3-chlorobenzoate, and from acinetobacter sp. strain p6, which grows on biphenyl, by using a continuous amalgamated culture apparatus. dna from strains cb15 and hf1 hybridized very strongly to each other, while hybridization between both parental strains, hf1 and p6, was negligible. however, dna from the recombinant cb15 hybridized moderately to strongly ...19921610186
biosorption of dichlorodiphenyltrichloroethane and hexachlorobenzene in groundwater and its implications for facilitated transport.the potential for enhanced mobility of hydrophobic pollutants by cotransport with bacteria in saturated soils was evaluated from measurements of biosorption of 14c-labeled hexachlorobenzene and dichlorodiphenyltrichloroethane (ddt) to five strains of soil and sewage bacteria. the sorption process could be described by a linear partition equation and appeared to be reversible, but desorption kinetics were slow and/or partly irreversible. the ddt partition coefficients varied with equilibration ti ...19921637158
biodegradation of mixtures of substituted benzenes by pseudomonas sp. strain js150.pseudomonas sp. strain js150 was isolated as a nonencapsulated variant of pseudomonas sp. strain js1 that contains the genes for the degradative pathways of a wide range of substituted aromatic compounds. pseudomonas sp. strain js150 grew on phenol, ethylbenzene, toluene, benzene, naphthalene, benzoate, p-hydroxybenzoate, salicylate, chlorobenzene, and several 1,4-dihalogenated benzenes. we designed experiments to determine the conditions required for induction of the individual pathways and to ...19921637161
lupanine hydroxylase, a quinocytochrome c from an alkaloid-degrading pseudomonas sp.lupanine 17-hydroxylase, the first enzyme in the pathway for bacterial degradation of the alkaloid, lupanine, was purified from a pseudomonas sp. the enzyme acts by initial dehydrogenation of the substrate, and cytochrome c was used as electron acceptor in assays. it had an mr of 66,000 by ultracentrifuge studies and 74,000 by gel filtration. the visible absorption spectrum was that of a cytochrome c, and a stoicheiometry of one haem group per molecule of enzyme was calculated. sds/page gave a s ...19911656935
identification of a novel composite transposable element, tn5280, carrying chlorobenzene dioxygenase genes of pseudomonas sp. strain p51.analysis of one of the regions of catabolic plasmid pp51 which encode chlorobenzene metabolism of pseudomonas sp. strain p51 revealed that the tcba and tcbb genes for chlorobenzene dioxygenase and dehydrogenase are located on a transposable element, tn5280. tn5280 showed the features of a composite bacterial transposon with iso-insertion elements (is1066 and is1067) at each end of the transposon oriented in an inverted position. when a 12-kb hindiii fragment of pp51 containing tn5280 was cloned ...19911657878
effect of sodium chloride on transport of bacteria in a saturated aquifer material.determinations were made of the influence of nacl concentration, cell density, and flow velocity on the transport of pseudomonas sp. strain kl2 through columns of aquifer sand under saturated conditions. a pulse-type boundary condition was used. the experiments were conducted by using 0.3-m-long plexiglas columns with an internal diameter of 0.05 m. when a 1-h pulse of a 0.01 m nacl solution containing 10(8) cells per ml was added at a flow rate of 10(-4) m s-1, the bacterial density in the effl ...19911662934
substrate interactions of benzene, toluene, and para-xylene during microbial degradation by pure cultures and mixed culture aquifer slurries.benzene, toluene, and p-xylene (btx) were degraded by indigenous mixed cultures in sandy aquifer material and by two pure cultures isolated from the same site. although btx compounds have a similar chemical structure, the fate of individual btx compounds differed when the compounds were fed to each pure culture and mixed culture aquifer slurries. the identification of substrate interactions aided the understanding of this behavior. beneficial substrate interactions included enhanced degradation ...19911746958
production of the siderophore aerobactin by a halophilic pseudomonad.a bacterial strain, isolated from a cyanobacterial culture, was identified as pseudomonas sp. strain x40. under iron-limiting conditions, the pseudomonas sp. produced aerobactin, a dihydroxamate siderophore previously found only in the family enterobacteriaceae. aerobactin was identified by electrophoretic mobility, spectrophotometric titration, proton nuclear magnetic resonance spectroscopy, mass spectrometry, acid hydrolysis, and biological activity. aerobactin was used as a siderophore in the ...19911768095
production and characterization of n-acyl-d-glutamate amidohydrolase from pseudomonas sp. strain 5f-1.n-acyl-d-glutamate amidohydrolase from pseudomonas sp. strain 5f-1 was inducibly produced by d isomers of n-acetylglutamate, glutamate, aspartate, and asparagine. the enzyme has been purified to homogeneity by deae-cellulose, (nh4)2so4 fractionation, and chromatofocusing followed by gel filtration on a sephadex g-100 column. the enzyme was a monomer with molecular weight of 55,000. the enzyme activity was optimal at ph 6.5 to 7.5 and 45 degrees c. the isoelectric point and the ph stability were ...19911768127
biotransformation of nitrobenzene by bacteria containing toluene degradative pathways.nonpolar nitroaromatic compounds have been considered resistant to attack by oxygenases because of the electron withdrawing properties of the nitro group. we have investigated the ability of seven bacterial strains containing toluene degradative pathways to oxidize nitrobenzene. cultures were induced with toluene vapor prior to incubation with nitrobenzene, and products were identified by high-performance liquid chromatography and gas chromatography-mass spectrometry. pseudomonas cepacia g4 and ...19911781679
biodegradation of 2,4-dinitrotoluene by a pseudomonas sp.previous studies of the biodegradation of nonpolar nitroaromatic compounds have suggested that microorganisms can reduce the nitro groups but cannot cleave the aromatic ring. we report here the initial steps in a pathway for complete biodegradation of 2,4-dinitrotoluene (dnt) by a pseudomonas sp. isolated from a four-member consortium enriched with dnt. the pseudomonas sp. degraded dnt as the sole source of carbon and energy under aerobic conditions with stoichiometric release of nitrite. during ...19911781682
purification and characterization of the n-methylcarbamate hydrolase from pseudomonas strain crl-ok.a unique cytosolic enzyme that hydrolyzes the carbamate linkage of the insecticide carbaryl (1-naphthyl n-methylcarbamate) was purified from extracts of pseudomonas sp. strain crl-ok. substrates of the hydrolase include the n-methylcarbamate pesticides carbofuran and aldicarb but not the phenylcarbamate isopropyl m-chlorocarbanilate, the thiocarbamate s-ethyl n,n-dipropylthiocarbamate, or the dimethylcarbamate o-nitrophenyldimethylcarbamate.19911785941
cloning and analysis of s-triazine catabolic genes from pseudomonas sp. strain nrrlb-12227.pseudomonas sp. strain nrrlb-12227 degrades the s-triazine melamine by a six-step pathway which allows it to use melamine and pathway intermediates as nitrogen sources. with the plasmid plg221, mutants defective in five of the six steps of the pathway were generated. tn5-containing-ecori fragments from these mutants were cloned and identified by selection for tn5-encoded kanamycin resistance in transformants. a restriction fragment from ammelide-negative mutant re411 was used as a probe in colon ...19911846859
extracellular lipase of pseudomonas sp. strain atcc 21808: purification, characterization, crystallization, and preliminary x-ray diffraction data.a procedure for the purification of a very hydrophobic lipase from pseudomonas sp. strain atcc 21808 was elaborated by avoiding the use of long-chain detergents in view of subsequent crystallization of the enzyme. the purification procedure included chromatography on q-sepharose in the presence of n-octyl-beta-d-glucopyranoside, ca2+ precipitation of fatty acids, and octyl-sepharose chromatography. the enzyme was purified 260-fold to a yield of 35% and a specific activity of 3,300 u/mg. the mole ...19911856176
isolation, sequence, and expression in escherichia coli of the pseudomonas sp. strain acp gene encoding 1-aminocyclopropane-1-carboxylate deaminase.pseudomonas sp. strain acp is capable of growth on 1-aminocyclopropane-1-carboxylate (acc) as a nitrogen source owing to induction of the enzyme acc deaminase and the subsequent conversion of acc to alpha-ketobutyrate and ammonia (m. honma, agric. biol. chem. 49:567-571, 1985). the complete amino acid sequence of purified acc deaminase was determined, and the sequence information was used to clone the acc deaminase gene from a 6-kb ecori fragment of pseudomonas sp. strain acp dna. dna sequence a ...19911885510
purification and characterization of benzoate-coenzyme a ligase and 2-aminobenzoate-coenzyme a ligases from a denitrifying pseudomonas sp.the enzymes catalyzing the formation of coenzyme a (coa) thioesters of benzoate and 2-aminobenzoate were studied in a denitrifying pseudomonas sp. anaerobically grown with these aromatic acids and nitrate as sole carbon and energy sources. three different rather specific aromatic acyl-coa ligases, e1, e2, and e3, were found which catalyze the formation of coa thioesters of benzoate, fluorobenzoates, and 2-aminobenzoate. atp is cleaved into amp and pyrophosphate. the enzymes were purified, their ...19911885526
hydrolysis of carbaryl by a pseudomonas sp. and construction of a microbial consortium that completely metabolizes carbaryl.two pseudomonas spp. (isolates 50552 and 50581) isolated from soil degraded 1-naphthol and carbaryl, an n-methylcarbamate pesticide, respectively. they utilized these compounds as a sole source of carbon. 1-naphthol was completely metabolized to co2 by the isolate 50552, while the carbaryl was first hydrolyzed to 1-naphthol and then converted into a brown-colored compound by the isolate 50581. the colored metabolite was not degraded, but 1-naphthol produced by the isolate 50581 during the expone ...19911903914
cloning and characterization of plasmid-encoded genes for the degradation of 1,2-dichloro-, 1,4-dichloro-, and 1,2,4-trichlorobenzene of pseudomonas sp. strain p51.pseudomonas sp. strain p51 is able to use 1,2-dichlorobenzene, 1,4-dichlorobenzene, and 1,2,4-trichlorobenzene as sole carbon and energy sources. two gene clusters involved in the degradation of these compounds were identified on a catabolic plasmid, pp51, with a size of 110 kb by using hybridization. they were further characterized by cloning in escherichia coli, pseudomonas putida kt2442, and alcaligenes eutrophus jmp222. expression studies in these organisms showed that the upper-pathway gene ...19911987135
cloning and comparison of the dna encoding ammelide aminohydrolase and cyanuric acid amidohydrolase from three s-triazine-degrading bacterial strains.dna encoding the catabolism of the s-triazines ammelide and cyanuric acid was cloned from pseudomonas sp. strain nrrlb-12228 and klebsiella pneumoniae 99 with, as a probe, a 4.6-kb psti fragment from a third strain, pseudomonas sp. strain nrrlb-12227, which also encodes these activities. in strains nrrlb-12228 and 99 the ammelide aminohydrolase (trzc) and cyanuric acid amidohydrolase (trzd) genes are located on identical 4.6-kb psti fragments which are part of a 12.4-kb dna segment present in bo ...19911991731
complete nucleotide sequences and comparison of the structural genes of two 2-haloalkanoic acid dehalogenases from pseudomonas sp. strain cbs3.the nucleotide sequences of two dna segments from pseudomonas sp. strain cbs3 that code for two different haloalkanoic acid halidohydrolases were determined. two open reading frames with coding capacities of 227 amino acids (corresponding to a molecular mass of 25,401 da) and 229 amino acids (corresponding to a molecular mass of 25,683 da) were identified as structural genes of 2-haloalkanoic acid dehalogenases i (dehci) and ii (dehcii) by comparison with the n-terminal amino acid sequences of t ...19911995594
solution behaviour of chromobacter viscosum and pseudomonas sp. lipases. no evidence of self-association.1. the size of two bacterial lipases was studied by sds/page, sedimentation velocity and sedimentation equilibrium to test for possible self-association behaviour. 2. mr values of selected lipases were obtained from sds/page and sedimentation-velocity measurements, together with an absolute determination by sedimentation equilibrium 3. the mr values obtained in a variety of aqueous solvents indicate that lipases do not self-associate in solution, suggesting the absence of surface hydrophobic pat ...19911996958
measurement of urinary lipopolysaccharide antibodies by elisa as a screen for urinary tract infection.five hundred and twenty two clinical urine specimens submitted for routine microbiological examination were tested in parallel by conventional microscopy and culture and for lipopolysaccharide antibodies by an enzyme linked immunoabsorbent assay (elisa) to assess the elisa as a screen for urinary tract infection. when the elisa alone was compared with routine methods the specificity sensitivity, and predictive value of positive and negative tests was 73.2%, 75.7%, 51.1% and 38.5%. for elisa with ...19911997536
sequence analysis of the pseudomonas sp. strain p51 tcb gene cluster, which encodes metabolism of chlorinated catechols: evidence for specialization of catechol 1,2-dioxygenases for chlorinated substrates.pseudomonas sp. strain p51 contains two gene clusters located on catabolic plasmid pp51 that encode the degradation of chlorinated benzenes. the nucleotide sequence of a 5,499-bp region containing the chlorocatechol-oxidative gene cluster tcbcdef was determined. the sequence contained five large open reading frames, which were all colinear. the functionality of these open reading frames was studied with various escherichia coli expression systems and by analysis of enzyme activities. the first g ...19912013566
simultaneous biodegradation of chlorobenzene and toluene by a pseudomonas strain.pseudomonas sp. strain js6 grows on a wide range of chloro- and methylaromatic substrates. the simultaneous degradation of these compounds is prevented in most previously studied isolates because the catabolic pathways are incompatible. the purpose of this study was to determine whether strain js6 could degrade mixtures of chloro- and methyl-substituted aromatic compounds. strain js6 was maintained in a chemostat on a minimal medium with toluene or chlorobenzene as the sole carbon source, suppli ...19912036002
resolution of 4-chlorobenzoate dehalogenase from pseudomonas sp. strain cbs3 into three components.extracts of pseudomonas sp. strain cbs3 grown with 4-chlorobenzoate as sole carbon source contained an enzyme that converted 4-chlorobenzoate to 4-hydroxybenzoate. this enzyme was shown to consist of three components, all necessary for the reaction. component i, which had a molecular weight of about 3,000, was highly unstable. components ii and iii were stable proteins with molecular weights of about 86,000 and 92,000.19912036019
characterization of the pseudomonas sp. strain p51 gene tcbr, a lysr-type transcriptional activator of the tcbcdef chlorocatechol oxidative operon, and analysis of the regulatory region.plasmid pp51 of pseudomonas sp. strain p51 contains two gene clusters encoding the degradation of chlorinated benzenes, tcbab and tcbcdef. a regulatory gene, tcbr, was located upstream and divergently transcribed from the chlorocatechol oxidative gene cluster tcbcdef. the tcbr gene was characterized by dna sequencing and expression studies with escherichia coli and pet8c and appeared to encode a 32-kda protein. the activity of the tcbr gene product was analyzed in pseudomonas putida kt2442, in w ...19912050630
transfer and expression of the catabolic plasmid pbrc60 in wild bacterial recipients in a freshwater ecosystem.3-chlorobenzoate (3cba)-degrading bacteria were isolated from the waters and sediments of flowthrough mesocosms dosed with various concentrations of 3cba and inoculated with a 3cba-degrading alcaligenes sp., strain br60. bacteria capable of 3cba degradation which were distinct from br60 were isolated. they carried pbrc60, a plasmid introduced with alcaligenes sp. strain br60 that carries a transposable element (tn5271) encoding 3cba degradation. the isolates expressed these genes in different wa ...199116348493
enhancement of the potential to utilize octopine in the nonfluorescent pseudomonas sp. strain 92.the nonfluorescent pseudomonas sp. strain 92 requires the presence of a supplementary carbon source for growth on octopine, whereas the spontaneous mutant rb100 has acquired the capacity to utilize this opine as the sole carbon and nitrogen source. insertional mutagenesis of rb100 with transposon tn5 generated mutants which were unable to grow on octopine and others which grew slowly on this substrate. both types of mutants yielded revertants that had regained the ability to utilize octopine. so ...199116348533
copper resistance gene homologs in pathogenic and saprophytic bacterial species from tomato.copper-resistant strains of xanthomonas campestris pv. vesicatoria, pseudomonas cichorii, pseudomonas putida, pseudomonas fluorescens, and a yellow pseudomonas sp. were isolated from tomato plants or seeds. in southern hybridizations, dna from each strain showed homology with the copper resistance (cop) operon previously cloned from pseudomonas syringae pv. tomato pt23. homology was associated with plasmid and chromosomal dna in x. compestris pv. vesicatoria, p. putida, and the yellow pseudomona ...199016348118
enhanced growth of wheat and soybean plants inoculated with azospirillum brasilense is not necessarily due to general enhancement of mineral uptake.the capacity of azospirillum brasilense to enhance the accumulation of k, p, ca, mg, s, na, mn, fe, b, cu, and zn in inoculated wheat and soybean plants was evaluated by using two different analytical methods with five a. brasilense strains originating from four distinct geographical regions. a pseudomonas isolate from the rhizosphere of zea mays seedlings was included as a control. all a. brasilense strains significantly improved wheat and soybean growth by increasing root and shoot dry weight ...199016348150
microbial degradation of quinoline and methylquinolines.several bacterial cultures were isolated that are able to degrade quinoline and to transform or to degrade methylquinolines. the degradation of quinoline by strains of pseudomonas aeruginosa qp and p. putida qp produced hydroxyquinolines, a transient pink compound, and other undetermined products. the quinoline-degrading strains of p. aeruginosa qp and p. putida qp hydroxylated a limited number of methylquinolines but could not degrade them, nor could they transform 2-methylquinoline, isoquinoli ...19902106283
formation of polyesters consisting of medium-chain-length 3-hydroxyalkanoic acids from gluconate by pseudomonas aeruginosa and other fluorescent pseudomonads.pseudomonas aeruginosa pao and 15 other strains of this species synthesized a polyester with 3-hydroxydecanoate as the main constituent (55 to 76 mol%) if the cells were cultivated in the presence of gluconate and if the nitrogen source was exhausted; 3-hydroxyhexanoate, 3-hydroxyoctanoate, and 3-hydroxydodecanoate were minor constituents of the polymer. the polymer was deposited in granules within the cell and amounted to 70% of the cell dry matter in some strains. among 55 different strains of ...19902125185
identification of an additional ferric-siderophore uptake gene clustered with receptor, biosynthesis, and fur-like regulatory genes in fluorescent pseudomonas sp. strain m114.five cosmid clones with insert sizes averaging 22.6 kilobases (kb) were isolated after complementation of 22 tn5-induced sid- mutants of pseudomonas sp. strain m114. one of these plasmids (pms639) was also shown to encode ferric-siderophore receptor and dissociation functions. the receptor gene was located on this plasmid since introduction of the plasmid into three wild-type fluorescent pseudomonads enabled them to utilize the ferric-siderophore from strain m114. the presence of an extra iron-r ...19902143887
starvation-specific formation of a peripheral exopolysaccharide by a marine pseudomonas sp., strain s9.the marine bacterium pseudomonas sp. strain s9 produces exopolysaccharides (eps) during both growth and total energy source and nutrient starvation. transmission electron microscopy of immunogold-labeled cells demonstrated that the eps is closely associated with the cell surface during growth (integral eps), while both the integral form and a loosely associated extracellular (peripheral) form were observed during starvation. formation and release of the latter rendered the starvation medium visc ...19902202255
purification and characterization of 4-methylmuconolactone methylisomerase, a novel enzyme of the modified 3-oxoadipate pathway in the gram-negative bacterium alcaligenes eutrophus jmp 134.4-carboxymethyl-4-methylbut-2-en-4-olide (4-methyl-2-enelactone) isomerase, transforming 4-methyl-2-enelactone to 3-methyl-2-enelactone, was purified from a derivative strain of pseudomonas sp. b13, named b13 fr1, carrying the plasmid pfrc2op. this plasmid contained the isomerase gene cloned from alcaligenes eutrophus jmp 134, which uses 4-methyl-2-enelactone as a carbon source. the enzyme consists of a single peptide chain of mr 40,000 as judged by sds/page. in addition to 4-methyl-2-enelactone ...19902241929
complete nucleotide sequence and polypeptide analysis of multicomponent phenol hydroxylase from pseudomonas sp. strain cf600.pseudomonas sp. strain cf600 metabolizes phenol and some of its methylated derivatives via a plasmid-encoded phenol hydroxylase and meta-cleavage pathway. the genes encoding the multicomponent phenol hydroxylase of this strain are located within a 5.5-kb saci-nrui fragment. we report the nucleotide sequence and the polypeptide products of this 5.5-kb region. a combination of deletion analysis, expression of subfragments in tac expression vectors, and identification of polypeptide products in max ...19902254258
in vitro analysis of polypeptide requirements of multicomponent phenol hydroxylase from pseudomonas sp. strain cf600.an in vitro study of the multicomponent phenol hydroxylase from pseudomonas sp. strain cf600 was performed. phenol-stimulated oxygen uptake from crude extracts was strictly dependent on the addition of nad(p)h and fe2+ to assay mixtures. five of six polypeptides required for growth on phenol were necessary for in vitro activity. one of the polypeptides was purified to homogeneity and found to be a flavin adenine dinucleotide containing iron-sulfur protein with significant sequence homology, at t ...19902254259
disposition of the prodrug 4-(bis (2-chloroethyl) amino) benzoyl-l-glutamic acid and its active parent drug in mice.a novel therapy for improving selectivity in cancer chemotherapy aims to modify distribution of a cytotoxic drug by generating it selectively at tumour sites. in this approach an antibody-enzyme conjugate is allowed to localise at the tumour sites before injecting a prodrug which is converted to an active drug specifically by the targeted enzyme in the conjugate. we present here pharmacokinetic studies on the prodrug 4-(bis (2-chloroethyl) amino) benzoyl-l-glutamic acid and its activated derivat ...19902257218
transformation of carbon tetrachloride by pseudomonas sp. strain kc under denitrification conditions.a denitrifying pseudomonas sp. (strain kc) capable of transforming carbon tetrachloride (ct) was isolated from groundwater aquifer solids. major products of the transformation of 14c-labeled ct by pseudomonas strain kc under denitrification conditions were 14co2 and an unidentified water-soluble fraction. little or no chloroform was produced. addition of dissolved trace metals, notably, ferrous iron and cobalt, to the growth medium appeared to enhance growth of pseudomonas strain kc while inhibi ...19902268146
cloning of a gene from pseudomonas sp. strain pg2982 conferring increased glyphosate resistance.a plasmid carrying a 2.4-kilobase-pair fragment of dna from pseudomonas sp. strain pg2982 has been isolated which was able to increase the glyphosate resistance of escherichia coli cells. the increase in resistance was dependent on the presence of a plasmid-encoded protein with a molecular weight of approximately 33,000, the product of a translational fusion between a gene on the vector, pacyc184, and the insert dna. an overlapping region of the pg2982 chromosome carrying the entire gene (design ...19902268152
biodegradation of p-nitrophenol in an aqueous waste stream by immobilized bacteria.microbiological analyses of activated sludge reactors after repeated exposure to 100 mg of p-nitrophenol (pnp) per liter resulted in the isolation of three pseudomonas species able to utilize pnp as a sole source of carbon and energy. cell suspensions of the three pseudomonas sp., designated pnp1, pnp2, and pnp3, mineralized 70, 60, and 45% of a 70-mg/liter dose of pnp in 24, 48, and 96 h, respectively. mass-balance analyses of pnp residues for all three cultures showed that undegraded pnp was l ...19902285309
purification and properties of nadh-ferredoxinnap reductase, a component of naphthalene dioxygenase from pseudomonas sp. strain ncib 9816.cells of pseudomonas sp. strain ncib 9816, after growth with naphthalene or salicylate, contain a multicomponent enzyme system that oxidizes naphthalene to cis-(1r,2s)-dihydroxy-1,2-dihydronaphthalene. we purified one of these components to homogeneity and found it to be an iron-sulfur flavoprotein that loses the flavin cofactor during purification. dialysis against flavin adenine dinucleotide (fad) showed that the enzyme bound 1 mol of fad per mol of enzyme protein. the enzyme consisted of a si ...19902294092
purification and properties of ferredoxinnap, a component of naphthalene dioxygenase from pseudomonas sp. strain ncib 9816.one of the three components of the naphthalene dioxygenase occurring in induced cells of pseudomonas sp. strain ncib 9816 has been purified to homogeneity. the protein contained 2 g-atoms each of iron and acid-labile sulfur and had an apparent molecular weight of 13,600. the evidence indicates that it is a ferredoxin-type protein that functions as an intermediate electron transfer protein in naphthalene dioxygenase activity.19902294093
cloning and sequencing of two tandem genes involved in degradation of 2,3-dihydroxybiphenyl to benzoic acid in the polychlorinated biphenyl-degrading soil bacterium pseudomonas sp. strain kks102.two genes involved in the degradation of biphenyl were isolated from a gene library of a polychlorinated biphenyl-degrading soil bacterium, pseudomonas sp. strain kks102, by using a broad-host-range cosmid vector, pks13. when a 3.2-kilobase (kb) psti fragment of a 29-kb cosmid dna insert was subcloned into puc18 at the psti site downstream of the lacz promoter, escherichia coli cells carrying this recombinant plasmid expressed 2,3-dihydroxybiphenyl dioxygenase activity. nucleotide sequencing of ...19892540155
microbiology of infected pilonidal sinuses.aspirates of pus from infected pilonidal sinuses in 75 patients showed bacterial growth. anaerobic bacteria only were recovered in 58 (77%) specimens, aerobic bacteria only in three (4%), and mixed aerobic and anaerobic bacteria in 14 (19%). two hundred and nine isolates were recovered: 147 anaerobes (2.0 isolates a specimen) and 62 aerobes (0.8 a specimen). the predominant anaerobes were bacteroides sp (81 isolates, including 29 bacteroides fragilis group) and 51 anaerobic cocci. the predominan ...19892584424
regulator and enzyme specificities of the tol plasmid-encoded upper pathway for degradation of aromatic hydrocarbons and expansion of the substrate range of the pathway.the tol plasmid upper pathway operon encodes enzymes involved in the catabolism of aromatic hydrocarbons such as toluene and xylenes. the regulator of the gene pathway, the xylr protein, exhibits a very broad effector specificity, being able to recognize as effectors not only pathway substrates but also a wide variety of mono- and disubstituted methyl-, ethyl-, and chlorotoluenes, benzyl alcohols, and p-chlorobenzaldehyde. benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase, two upper pa ...19892687253
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