| 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 ... | 1994 | 7944378 |
| 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 ... | 1994 | 7993091 |
| 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 ... | 1993 | 8419290 |
| 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 ... | 1993 | 8434917 |
| 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 ... | 1994 | 8002579 |
| dihydroxylation and dechlorination of chlorinated biphenyls by purified biphenyl 2,3-dioxygenase from pseudomonas sp. strain lb400. | oxidation of biphenyl and nine chlorinated biphenyls (cbs) by the biphenyl 2,3-dioxygenase from pseudomonas sp. strain lb400 was examined. the purified terminal oxygenase required the addition of partially purified electron transport components, nad(p)h, and ferrous iron to oxidize biphenyl and cbs. cis-biphenyl 2,3-dihydrodiol was produced with biphenyl as the substrate. dihydrodiols were produced from all cbs, and more than one compound was produced with most substrates. catechols were produce ... | 1995 | 8002618 |
| genetic organization of the mau gene cluster in methylobacterium extorquens am1: complete nucleotide sequence and generation and characteristics of mau mutants. | the nucleotide sequence of the methylamine utilization (mau) gene region from methylobacterium extorquens am1 was determined. open reading frames for 11 genes (maufbedacjglmn) were found, all transcribed in the same orientation. the maub, maua, and mauc genes encode the periplasmic methylamine dehydrogenase (madh) large and small subunit polypeptides and amicyanin, respectively. the products of maud, maug, maul, and maum were also predicted to be periplasmic. the products of mauf, maue, and maun ... | 1994 | 8021187 |
| nucleotide sequence and functional analysis of the meta-cleavage pathway involved in biphenyl and polychlorinated biphenyl degradation in pseudomonas sp. strain kks102. | pseudomonas sp. strain kks102 is able to degrade biphenyl and polychlorinated biphenyls via the meta-cleavage pathway. we sequenced the upstream region of the bpha1a2a3bcd (open reading frame 1 [orf1]) a4 and found four orfs in this region. as the deduced amino acid sequences of the first, second, and third orfs are homologous to the meta-cleavage enzymes from pseudomonas sp. strain cf600 (v. shingler, j. powlowski, and u. marklund, j. bacteriol. 174:711-724, 1992), these orfs have been named bp ... | 1994 | 8021212 |
| 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 ... | 1993 | 8468288 |
| degradation of alkylphenol ethoxylates by pseudomonas sp. strain tr01. | an alkylphenol ethoxylate-degrading bacterium was isolated from activated sludge of a municipal sewage treatment plant by enrichment culture. this organism was found to belong to the genus pseudomonas; since no corresponding species was identified, we designated it as pseudomonas sp. strain tr01. this strain had an optimal temperature and ph of 30 degrees c and 7, respectively, for both growth and the degradation of triton n-101 (a nonylphenol ethoxylate in which the average number of ethylene o ... | 1994 | 8074508 |
| evidence for a novel pathway in the degradation of fluorene by pseudomonas sp. strain f274. | a fluorene-utilizing microorganism, identified as a species of pseudomonas, was isolated from soil severely contaminated from creosote use and was shown to accumulate six major metabolites from fluorene in washed-cell incubations. five of these products were identified as 9-fluorenol, 9-fluorenone, (+)-1,1a-dihydroxy-1-hydro-9-fluorenone, 8-hydroxy-3,4-benzocoumarin, and phthalic acid. this last compound was also identified in growing cultures supported by fluorene. fluorene assimilation into ce ... | 1994 | 8074523 |
| 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 ... | 1993 | 8509325 |
| azoreductase activity in bacteria associated with the greening of instant chocolate puddings. | pseudomonas sp. strain azr1 and klebsiella sp. strain azr2 were isolated from reconstituted instant chocolate puddings that had turned green and were found to have azoreductase activity. this activity was inducible and nadh dependent. differences in dye reduction rates between the two strains were apparent, and substrate specificity related to dye structure was observed. | 1994 | 8085839 |
| identification and characterization of the treponema pallidum tpn50 gene, an ompa homolog. | treponema pallidum is a pathogenic spirochete that has no known genetic exchange mechanisms. in order to identify treponemal genes encoding surface and secreted proteins, we carried out tnphoa mutagenesis of a t. pallidum genomic dna library in escherichia coli. several of the resulting clones expressed enzymatically active t. pallidum-alkaline phosphatase fusion proteins. the dna sequence of the 5' portion of a number of the treponemal genes was obtained and analyzed. a recombinant clone harbor ... | 1994 | 8112835 |
| sensing of aromatic compounds by the dmpr transcriptional activator of phenol-catabolizing pseudomonas sp. strain cf600. | the dmp operon of the pvi150 catabolic plasmid of pseudomonas sp. strain cf600 encodes the enzymes involved in the catabolism of phenol and methylphenols. the regulator of this dmp pathway, dmpr, is a member of the ntrc family of transcriptional activators and controls transcription of the dmp operon in response to aromatic effector compounds (v. shingler, m. bartilson, and t. moore, j. bacteriol. 175:1596-1604, 1993). using a lux gene fusion reporter system, in which the dmpr-regulated operon p ... | 1994 | 8132448 |
| identification of the bpha4 gene encoding ferredoxin reductase involved in biphenyl and polychlorinated biphenyl degradation in pseudomonas sp. strain kks102. | the nucleotide sequence of the downstream region of the bph operon from pseudomonas sp. strain kks102 was determined. two open reading frames (orf1 and orf2) were found in this region, and the deduced amino acid sequence of orf2 showed homology with the sequences of four ferredoxin reductases of dioxygenase systems. when this region was inserted just upstream of the bph operon, which does not contain a gene encoding ferredoxin reductase, biphenyl dioxygenase activity was detected. the 24- and 44 ... | 1994 | 8132464 |
| analysis of the binding site of the lysr-type transcriptional activator tcbr on the tcbr and tcbc divergent promoter sequences. | the tcbr transcriptional activator protein, which is encoded by the tcbr gene of pseudomonas sp. strain p51 (j. r. van der meer, a. c. j. frijters, j. h. j. leveau, r. i. l. eggen, a. j. b. zehnder, and w. m. de vos, j. bacteriol. 173:3700-3708, 1991), was purified from overproducing escherichia coli cells by using a two-step chromatographic procedure. subsequent use of tcbr in gel mobility shift assays with progressively shortened portions of a dna fragment containing the divergent promoter seq ... | 1994 | 8144450 |
| catechol 2,3-dioxygenases functional in oxygen-limited (hypoxic) environments. | we studied the degradation of toluene for bacteria isolated from hypoxic (i.e., oxygen-limited) petroleum-contaminated aquifers and compared such strains with other toluene degraders. three pseudomonas isolates, p. pickettii pko1, pseudomonas sp. strain w31, and p. fluorescens cfs215, grew on toluene when nitrate was present as an alternate electron acceptor in hypoxic environments. we examined kinetic parameters (k(m) and vmax) for catechol 2,3-dioxygenase (c230), a key shared enzyme of the tol ... | 1996 | 8633871 |
| metabolism of both 4-chlorobenzoate and toluene under denitrifying conditions by a constructed bacterial strain. | t1, a dentrifying bacterium originally isolated for its ability to grow on toluene, can also metabolize 4-hydroxybenzoate and other aromatic compounds under denitrifying conditions. a cosmid clone carrying the three genes that code for the 4-chlorobenzoate dehalogenase enzyme complex isolated from the aerobic bacterium pseudomonas sp. strain cbs3 was successfully conjugated into strain t1. the cloned enzyme complex catalyzes the hydrolytic dechlorination of 4-chlorobenzoate to 4-hydroxybenzoate. ... | 1994 | 8161190 |
| chloroform mineralization by toluene-oxidizing bacteria. | seven toluene-oxidizing bacterial strains (pseudomonas mendocina kr1, burkholderia cepacia g4, pseudomonas putida f1, pseudomonas pickettii pko1, and pseudomonas sp. strains envpc5, envbf1, and env113) were tested for their ability to degrade chloroform (cf). the greatest rate of cf oxidation was achieved with strain envbf1 (1.9 nmol/min/mg of cell protein). cf also was oxidized by p. mendocina kr1 (0.48 nmol/min/mg of cell protein), strain envpc5 (0.49 nmol/min/mg of cell protein), and escheric ... | 1996 | 8702263 |
| 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 ... | 1994 | 8195105 |
| 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 ... | 1993 | 8250561 |
| 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 ... | 1993 | 8278546 |
| 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 ... | 1993 | 8285689 |
| 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 ... | 1993 | 8285706 |
| 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 ... | 1993 | 8328798 |
| 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 ... | 1993 | 8335640 |
| oxidation of 6,7-dihydro-5h-benzocycloheptene by bacterial strains expressing naphthalene dioxygenase, biphenyl dioxygenase, and toluene dioxygenase yields homochiral monol or cis-diol enantiomers as major products. | bacterial strains expressing naphthalene, biphenyl, and toluene dioxygenase were examined for their abilities to oxidize 6,7-dihydro-5h-benzocycloheptene (benzocyclohept-1-ene). the major oxidation products were isolated, and their absolute configurations were determined by chiral 1h nuclear magnetic resonance analysis of diastereomeric boronate esters, chiral stationary-phase high-pressure liquid chromatography, and stereo-chemical correlation. pseudomonas sp. strain 9816/11 and sphingomonas ya ... | 1996 | 8919798 |
| 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 ... | 1993 | 8357248 |
| comparison of factors influencing trichloroethylene degradation by toluene-oxidizing bacteria. | the degradation of trichloroethylene (tce) by toluene-oxidizing bacteria has been extensively studied, and yet the influence of environmental conditions and physiological characteristics of individual strains has received little attention. to consider these effects, the levels of tce degradation by strains distinguishable on the basis of toluene and nitrate metabolism were compared under aerobic or hypoxic conditions in the presence and absence of nitrate and an exogenous electron donor, lactate ... | 1996 | 8975612 |
| 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 ... | 1993 | 8357257 |
| 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 ... | 1993 | 8407778 |
| 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 ... | 1993 | 8419288 |
| heterologous expression of biphenyl dioxygenase-encoding genes from a gram-positive broad-spectrum polychlorinated biphenyl degrader and characterization of chlorobiphenyl oxidation by the gene products. | the bpha1a2a3a4 gene cluster, encoding a biphenyl dioxygenase from rhodococcus globerulus p6, a gram-positive microorganism able to degrade a wide spectrum of polychlorobiphenyls (pcbs), was expressed in pseudomonas putida, thereby allowing characterization of chlorobiphenyl oxidation by this enzyme. while p6 biphenyl dioxygenase activity was observed in p. putida containing bpha1a2a3a4, no activity was detected in escherichia coli cells containing the same gene cluster. in e. coli, transcriptio ... | 1997 | 9068637 |
| 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 ... | 1993 | 8439151 |
| 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 ... | 1993 | 8449869 |
| stereospecific oxidation of (r)- and (s)-1-indanol by naphthalene dioxygenase from pseudomonas sp. strain ncib 9816-4. | a recombinant escherichia coli strain which expresses naphthalene dioxygenase (ndo) from pseudomonas sp. strain ncib 9816-4 oxidized (s)-1-indanol to trans-(1s,3s)-indan-1,3-diol (95.5%) and (r)-3-hydroxy-1-indanone (4.5%). the same cells oxidized (r)-1-indanol to cis-1,3-indandiol (71%), (r)-3-hydroxy-1-indanone (18.2%), and cis-1,2,3-indantriol (10.8%). purified ndo oxidized (s)-1-indenol to both syn- and anti-2,3-dihydroxy-1-indanol. | 1997 | 9143136 |
| 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 ... | 1993 | 8449871 |
| 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 ... | 1993 | 8449889 |
| 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 ... | 1993 | 8481010 |
| bacterial dl-2-haloacid dehalogenase from pseudomonas sp. strain 113: gene cloning and structural comparison with d- and l-2-haloacid dehalogenases. | dl-2-haloacid dehalogenase from pseudomonas sp. strain 113 (dl-dex) catalyzes the hydrolytic dehalogenation of both d- and l-2-haloalkanoic acids to produce the corresponding l- and d-2-hydroxyalkanoic acids, respectively, with inversion of the c2 configuration. dl-dex is a unique enzyme: it acts on the chiral carbon of the substrate and uses both enantiomers as equivalent substrates. we have isolated and sequenced the gene encoding dl-dex. the open reading frame consists of 921 bp corresponding ... | 1997 | 9209038 |
| cloning of genes involved in carbazole degradation of pseudomonas sp. strain ca10: nucleotide sequences of genes and characterization of meta-cleavage enzymes and hydrolase. | the dna fragment encoding meta-cleavage enzymes and the meta-cleavage compound hydrolase, involved in carbazole degradation, was cloned from the carbazole-utilizing bacterium pseudomonas sp. strain ca10. dna sequence analysis of this 2.6-kb smai-sphi fragment revealed that there were three open reading frames (orf1, orf2, and orf3, in this gene order). orf1 and orf2 were indispensable for meta-cleavage activity for 2'-aminobiphenyl-2,3-diol and its easily available analog, 2,3-dihydroxybiphenyl, ... | 1997 | 9244273 |
| purification and characterization of thermostable and nonthermostable 2-haloacid dehalogenases with different stereospecificities from pseudomonas sp. strain yl. | two novel hydrolytic dehalogenases, thermostable l-2-haloacid dehalogenase (l-dex) inducibly synthesized by 2-chloropropionate (2-cpa) and nonthermostable dl-2-haloacid dehalogenase (dl-dex) induced by 2-chloroacrylate, were purified to homogeneity from pseudomonas sp. strain yl. dl-dex consisted of a monomer with a molecular weight of about 36,000 and catalyzed the dehalogenation of l and d isomers of 2-cpa to produce d- and l-lactates, respectively. it acted on 2-haloalkanoic acids with a carb ... | 1994 | 8074519 |
| 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 ... | 1993 | 8517744 |
| 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 ... | 1993 | 8517754 |
| maleylacetate reductases in chloroaromatic-degrading bacteria using the modified ortho pathway: comparison of catalytic properties. | the maleylacetate reductases from pseudomonas aeruginosa rho1 and alcaligenes eutrophus jmp134 were tested for activity and affinity to various maleylacetates as well as dechlorinating properties. the dechlorinating activity and the kcat/km values revealed high-level similarity of these reductases to that of pseudomonas sp. strain b13. | 1996 | 8550433 |
| chemotaxis of pseudomonas spp. to the polyaromatic hydrocarbon naphthalene. | two naphthalene-degrading bacteria, pseudomonas putida g7 and pseudomonas sp. strain ncib 9816-4, were chemotactically attracted to naphthalene in drop assays and modified capillary assays. growth on naphthalene or salicylate induced the chemotactic response. p. putida g7 was also chemotactic to biphenyl; other polyaromatic hydrocarbons that were tested did not appear to be chemoattractants for either pseudomonas strain. strains that were cured of the naphthalene degradation plasmid were not att ... | 1997 | 9327579 |
| comparative in vitro activities of trovafloxacin (cp-99,219) against 221 aerobic and 217 anaerobic bacteria isolated from patients with intra-abdominal infections. | four hundred thirty-eight bacteria cultured from specimens of patients with serious intra-abdominal infections were tested by agar dilution against trovafloxacin and other quinolones and antimicrobial agents. trovafloxacin inhibited 435 strains (99.3%) at < or =2 microg/ml. all the quinolones had similar activities against enterobacteriaceae and pseudomonas sp., but trovafloxacin showed superior activities against streptococci, enterococci, and anaerobic organisms. because of its excellent in vi ... | 1997 | 9333074 |
| genetic structures of the genes encoding 2,3-dihydroxybiphenyl 1,2-dioxygenase and 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid hydrolase from biphenyl- and 4-chlorobiphenyl-degrading pseudomonas sp. strain dj-12. | the pcbc and pcbd genes of pseudomonas sp. strain dj-12, a natural isolate degrading biphenyl and 4-chlorobiphenyl, encode the 2,3-dihydroxybiphenyl 1,2-dioxygenase and 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid hydrolase, respectively. the two genes were sequenced and appear to be present in the order pcbd-pcbc as an operon. | 1996 | 8572703 |
| atzc is a new member of the amidohydrolase protein superfamily and is homologous to other atrazine-metabolizing enzymes. | pseudomonas sp. strain adp metabolizes atrazine to cyanuric acid via three plasmid-encoded enzymes, atza, atzb, and atzc. the first enzyme, atza, catalyzes the hydrolytic dechlorination of atrazine, yielding hydroxyatrazine. the second enzyme, atzb, catalyzes hydroxyatrazine deamidation, yielding n-isopropylammelide. in this study, the third gene in the atrazine catabolic pathway, atzc, was cloned from a pseudomonas sp. strain adp cosmid library as a 25-kb ecori dna fragment in escherichia coli. ... | 1998 | 9422605 |
| detoxification of protoanemonin by dienelactone hydrolase. | protoanemonin is a toxic metabolite which may be formed during the degradation of some chloroaromatic compounds, such as polychlorinated biphenyls, by natural microbial consortia. we show here that protoanemonin can be transformed by dienelactone hydrolase of pseudomonas sp. strain b13 to cis-acetylacrylate. although similar km values were observed for cis-dienelactone and protoanemonin, the turnover rate of protoanemonin was only 1% that of cis-dienelactone. this indicates that at least this pe ... | 1998 | 9440530 |
| a cold-adapted lipase of an alaskan psychrotroph, pseudomonas sp. strain b11-1: gene cloning and enzyme purification and characterization. | a psychrotrophic bacterium producing a cold-adapted lipase upon growth at low temperatures was isolated from alaskan soil and identified as a pseudomonas strain. the lipase gene (lipp) was cloned from the strain and sequenced. the amino acid sequence deduced from the nucleotide sequence of the gene (924 bp) corresponded to a protein of 308 amino acid residues with a molecular weight of 33,714. lipp also has consensus motifs conserved in other cold-adapted lipases, i.e., lipase 2 from antarctic m ... | 1998 | 9464382 |
| biochemical and genetic characterization of trans-2'-carboxybenzalpyruvate hydratase-aldolase from a phenanthrene-degrading nocardioides strain. | trans-2'-carboxybenzalpyruvate hydratase-aldolase was purified from a phenanthrene-degrading bacterium, nocardioides sp. strain kp7, and characterized. the purified enzyme was found to have molecular masses of 38 kda by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 113 kda by gel filtration chromatography. thus, the homotrimer of the 38-kda subunit constituted an active enzyme. the km and kcat values of this enzyme for trans-2'-carboxybenzalpyruvate were 50 microm and 13 s(-1), r ... | 1998 | 9473051 |
| genetic and functional analysis of the styrene catabolic cluster of pseudomonas sp. strain y2. | the chromosomal region of pseudomonas sp. strain y2 involved in the conversion of styrene to phenylacetate (upper catabolic pathway) has been cloned and sequenced. four catabolic genes, styabcd, and two regulatory genes, stysr, were identified. this gene cluster when transferred to escherichia coli w confers to this phenylacetate-degrading host the ability to grow on styrene as the sole carbon and energy source. genes styabcd are homologous to those encoding the styrene upper catabolic pathway i ... | 1998 | 9495743 |
| enzyme specificity of 2-nitrotoluene 2,3-dioxygenase from pseudomonas sp. strain js42 is determined by the c-terminal region of the alpha subunit of the oxygenase component. | biotransformations with recombinant escherichia coli expressing the genes encoding 2-nitrotoluene 2,3-dioxygenase (2ntdo) from pseudomonas sp. strain js42 demonstrated that 2ntdo catalyzes the dihydroxylation and/or monohydroxylation of a wide range of aromatic compounds. extremely high nucleotide and deduced amino acid sequence identity exists between the components from 2ntdo and the corresponding components from 2,4-dinitrotoluene dioxygenase (2,4-dntdo) from burkholderia sp. strain dnt (form ... | 1998 | 9495758 |
| a novel dipeptidyl aminopeptidase from pseudomonas sp. strain wo24. | an activity similar to that of dipeptidyl aminopeptidase i (dap i) which releases dipeptide from gly-arg-p-nitroanilide (gly-arg-pna) was detected in a pseudomonas sp. an enzyme was isolated and purified about 400-fold by a series of column chromatographies. the enzyme, named dap bi (dap from bacteria, type i), was revealed to be homogeneous by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) and isoelectric focusing. the molecular mass was estimated to be 82 kda by sds-page ... | 1996 | 8631703 |
| ntn genes determining the early steps in the divergent catabolism of 4-nitrotoluene and toluene in pseudomonas sp. strain tw3. | pseudomonas sp. strain tw3 is able to oxidatively metabolize 4-nitrotoluene and toluene via a route analogous to the upper pathway of the tol plasmids. we report the sequence and organization of five genes, ntnwcmab*, which are very similar to and in the same order as the xyl operon of tol plasmid pww0 and present evidence that they encode enzymes which are expressed during growth on both 4-nitrotoluene and toluene and are responsible for their oxidation to 4-nitrobenzoate and benzoate, respecti ... | 1998 | 9555884 |
| a gene cluster encoding steps in conversion of naphthalene to gentisate in pseudomonas sp. strain u2. | pseudomonas sp. strain u2 was isolated from oil-contaminated soil in venezuela by selective enrichment on naphthalene as the sole carbon source. the genes for naphthalene dioxygenase were cloned from the plasmid dna of strain u2 on an 8.3-kb bamhi fragment. the genes for the naphthalene dioxygenase genes nagaa (for ferredoxin reductase), nagab (for ferredoxin), and nagac and nagad (for the large and small subunits of dioxygenase, respectively) were located by southern hybridizations and by nucle ... | 1998 | 9573207 |
| towards a biocatalyst for (s)-styrene oxide production: characterization of the styrene degradation pathway of pseudomonas sp. strain vlb120. | in order to design a biocatalyst for the production of optically pure styrene oxide, an important building block in organic synthesis, the metabolic pathway and molecular biology of styrene degradation in pseudomonas sp. strain vlb120 was investigated. a 5.7-kb xhoi fragment, which contained on the same strand of dna six genes involved in styrene degradation, was isolated from a gene library of this organism in escherichia coli by screening for indigo formation. t7 rna polymerase expression expe ... | 1998 | 9603811 |
| low-frequency horizontal transfer of an element containing the chlorocatechol degradation genes from pseudomonas sp. strain b13 to pseudomonas putida f1 and to indigenous bacteria in laboratory-scale activated-sludge microcosms. | the possibilities for low-frequency horizontal transfer of the self-transmissible chlorocatechol degradative genes (clc) from pseudomonas sp. strain b13 were investigated in activated-sludge microcosms. when the clc genes were transferred into an appropriate recipient bacterium such as pseudomonas putida f1, a new metabolic pathway for chlorobenzene degradation was formed by complementation which could be selected for by the addition of mono- or 1, 4-dichlorobenzene (cb). under optimized conditi ... | 1998 | 9603824 |
| stereospecific dihydroxylation of the styrene vinyl group by purified naphthalene dioxygenase from pseudomonas sp. strain ncib 9816-4. | naphthalene dioxygenase (ndo) from pseudomonas sp. strain ncib 9816-4 adds both atoms of the dioxygen molecule to styrene to form (r)-l-phenyl-1,2-ethanediol. product formation is tightly coupled to dioxygen consumption and nadh oxidation. ndo oxidizes styrene-d8 at almost the same initial rate as styrene. the results indicate that dioxygen activation by ndo is different from that by cytochrome p-450 and other monooxygenases, which oxidize styrene to styrene 1,2-oxide. | 1996 | 8655521 |
| atrazine chlorohydrolase from pseudomonas sp. strain adp: gene sequence, enzyme purification, and protein characterization. | pseudomonas sp. strain adp metabolizes atrazine to carbon dioxide and ammonia via the intermediate hydroxyatrazine. the genetic potential to produce hydroxyatrazine was previously attributed to a 1.9-kb avai dna fragment from strain adp (m. l. de souza, l. p. wackett, k. l. boundy-mills, r. t. mandelbaum, and m. j. sadowsky, appl. environ. microbiol. 61:3373-3378, 1995). in this study, sequence analysis of the 1.9-kb avai fragment indicated that a single open reading frame, atza, encoded an acti ... | 1996 | 8759853 |
| construction and use of an ipb dna module to generate pseudomonas strains with constitutive trichloroethene and isopropylbenzene oxidation activity. | pseudomonas sp. strain jr1 exhibits trichloroethene (tce) oxidation activity with isopropylbenzene (ipb) as the inducer substrate. we previously reported the genes encoding the first three enzymes of the ipb-degradative pathway (ipba1, ipba2, ipba3, ipba4, ipbb, and ipbc) and identified the initial ipb dioxygenase (ipba1 a2a3a4) as responsible for tce cooxidation (u. pflugmacher, b. averhoff, and g. gottschalk, appl. environ. microbiol. 62:3967-3977, 1996). primer extension analyses revealed mul ... | 1998 | 9647815 |
| cloning of a sphingomonas paucimobilis syk-6 gene encoding a novel oxygenase that cleaves lignin-related biphenyl and characterization of the enzyme. | sphingomonas paucimobilis syk-6 transforms 2,2'-dihydroxy-3,3'-dimethoxy-5,5'-dicarboxybiphenyl (ddva), a lignin-related biphenyl compound, to 5-carboxyvanillic acid via 2,2',3-trihydroxy-3'-methoxy-5,5'-dicarboxybiphenyl (oh-ddva) as an intermediate (15). the ring fission of oh-ddva is an essential step in the ddva degradative pathway. a 15-kb ecori fragment isolated from the cosmid library complemented the growth deficiency of a mutant on oh-ddva. subcloning and deletion analysis showed that a ... | 1998 | 9647824 |
| chromosomal integration, tandem amplification, and deamplification in pseudomonas putida f1 of a 105-kilobase genetic element containing the chlorocatechol degradative genes from pseudomonas sp. strain b13. | analysis of chlorobenzene-degrading transconjugants of pseudomonas putida f1 which had acquired the genes for chlorocatechol degradation (clc) from pseudomonas sp. strain b13 revealed that the clc gene cluster was present on a 105-kb amplifiable genetic element (named the clc element). in one such transconjugant, p. putida rr22, a total of seven or eight chromosomal copies of the entire genetic element were present when the strain was cultivated on chlorobenzene. chromosomal integrations of the ... | 1998 | 9721270 |
| purification and characterization of the coniferyl aldehyde dehydrogenase from pseudomonas sp. strain hr199 and molecular characterization of the gene. | the coniferyl aldehyde dehydrogenase (caldh) of pseudomonas sp. strain hr199 (dsm7063), which catalyzes the nad+-dependent oxidation of coniferyl aldehyde to ferulic acid and which is induced during growth with eugenol as the carbon source, was purified and characterized. the native protein exhibited an apparent molecular mass of 86,000 +/- 5,000 da, and the subunit mass was 49.5 +/- 2.5 kda, indicating an alpha2 structure of the native enzyme. the optimal oxidation of coniferyl aldehyde to feru ... | 1998 | 9721273 |
| pseudomonas sp. strain 273, an aerobic alpha, omega-dichloroalkanedegrading bacterium. | a gram-negative, aerobic bacterium was isolated from soil; this bacterium grew in 50% (vol/vol) suspensions of 1,10-dichlorodecane (1,10-dcd) as the sole source of carbon and energy. phenotypic and small-subunit ribosomal rna characterizations identified the organism, designated strain 273, as a member of the genus pseudomonas. after induction with 1,10-dcd, pseudomonas sp. strain 273 released stoichiometric amounts of chloride from c5 to c12 alpha, omega-dichloroalkanes in the presence of oxyge ... | 1998 | 9726906 |
| identification and characterization of is1411, a new insertion sequence which causes transcriptional activation of the phenol degradation genes in pseudomonas putida. | a new insertion sequence (is element), is1411, was identified downstream of the phenol degradation genes pheba that originated from plasmid dna of pseudomonas sp. strain est1001. according to sequence analysis, is1411 belongs to a new family of is elements that has recently been named the isl3 family (j. mahillon and m. chandler, microbiol. mol. biol. rev. 62:725-774, 1998). is1411 generates 8-bp duplication of the target dna and carries 24-bp inverted repeats (irs), highly homologous to the irs ... | 1998 | 9765560 |
| int-b13, an unusual site-specific recombinase of the bacteriophage p4 integrase family, is responsible for chromosomal insertion of the 105-kilobase clc element of pseudomonas sp. strain b13. | pseudomonas sp. strain b13 carries the clcrabde genes encoding chlorocatechol-degradative enzymes on the self-transmissible 105-kb clc element. the element integrates site and orientation specifically into the chromosomes of various bacterial recipients, with a glycine trna structural gene (glyv) as the integration site. we report here the localization and nucleotide sequence of the integrase gene and the activity of the integrase gene product in mediating site-specific integration. the integras ... | 1998 | 9791097 |
| toluene and ethylbenzene oxidation by purified naphthalene dioxygenase from pseudomonas sp. strain ncib 9816-4. | purified naphthalene dioxygenase (ndo) from pseudomonas sp. strain ncib 9816-4 oxidized toluene to benzyl alcohol and benzaldehyde by reactions involving benzylic monooxygenation and dioxygen-dependent alcohol oxidation, respectively. xylene and nitrotoluene isomers were also oxidized to substituted benzyl alcohol and benzaldehyde derivatives. ndo oxidized ethylbenzene sequentially through (s)-1-phenethyl alcohol (77% enantiomeric excess) and acetophenone to 2-hydroxyacetophenone. in addition, n ... | 1996 | 8795196 |
| phenotypic and genotypic characterization of phenanthrene-degrading fluorescent pseudomonas biovars. | a total of 41 phenanthrene degraders were isolated from a former coal gasification site by using pseudomonas-selective gould's s1 medium. all isolates were found to belong to the fluorescent pseudomonas group and were subjected to characterization by phenotypic methods, including classical taxonomic tests, api 20ne, and biolog gn, and the strains were further characterized by the genotypic method repetitive extragenic palindromic pcr (rep-pcr). by using classical tests, the population was found ... | 1996 | 8837438 |
| involvement of the terminal oxygenase beta subunit in the biphenyl dioxygenase reactivity pattern toward chlorobiphenyls. | biphenyl dioxygenase (bph dox) oxidizes biphenyl on adjacent carbons to generate 2,3-dihydro-2,3-dihydroxybiphenyl in comamonas testosteroni b-356 and in pseudomonas sp. strain lb400. the enzyme comprises a two-subunit (alpha and beta) iron sulfur protein (ispbph), a ferredoxin (ferbph), and a ferredoxin reductase (redbph). b-356 bph dox preferentially catalyzes the oxidation of the double-meta-substituted congener 3,3'-dichlorobiphenyl over the double-para-substituted congener 4,4'-dichlorobiph ... | 1998 | 9811638 |
| genetic exchange in soil between introduced chlorobenzoate degraders and indigenous biphenyl degraders. | pseudomonas aeruginosa jb2, a chlorobenzoate degrader, was inoculated into soil having indigenous biphenyl degraders but no identifiable 2-chlorobenzoate (2cba) or 2,5-dichlorobenzoate (2,5dcba) degraders. the absence of any indigenous chlorobenzoate degraders was noted by the failure to obtain enrichment cultures with the addition of 2cba, 3cba, or 2,5dcba and by the failure of soil dna to hybridize to the tfdc gene, which encodes ortho fission of chlorocatechols. in contrast, dna extracted fro ... | 1996 | 8837452 |
| cloning and molecular analysis of the poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyalkanoate) biosynthesis genes in pseudomonas sp. strain 61-3. | two types of polyhydroxyalkanoate (pha) biosynthesis gene loci (phb and pha) of pseudomonas sp. strain 61-3, which produces a blend of poly(3-hydroxybutyrate) [p(3hb)] homopolymer and a random copolymer (poly(3-hydroxybutyrate-co-3-hydroxyalkanoate) [p(3hb-co-3ha]) consisting of 3ha units of 4 to 12 carbon atoms, were cloned and analyzed at the molecular level. in the phb locus, three open reading frames encoding polyhydroxybutyrate (phb) synthase (phbcps), beta-ketothiolase (phbaps), and nadph- ... | 1998 | 9851987 |
| genetic and biochemical analyses of the tec operon suggest a route for evolution of chlorobenzene degradation genes. | the teca broad-spectrum chlorobenzene dioxygenase of burkholderia sp. strain ps12 catalyzes the first step in the mineralization of 1,2,4, 5-tetrachlorobenzene. the catabolic genes were localized on a small plasmid that belongs to the incpbeta incompatibility group. pcr analysis of the genetic environment of the tec genes indicated high similarity to the transposon-organized catabolic tcb chlorobenzene degradation genes of pseudomonas sp. strain p51. sequence analysis of the regions flanking the ... | 1999 | 9864349 |
| thermal gradient gel electrophoresis analysis of bioprotection from pollutant shocks in the activated sludge microbial community. | we used a culture-independent approach, namely, thermal gradient gel electrophoresis (tgge) analysis of ribosomal sequences amplified directly from community dna, to determine changes in the structure of the microbial community following phenol shocks in the highly complex activated sludge ecosystem. parallel experimental model sewage plants were given shock loads of chlorinated and methylated phenols and simultaneously were inoculated (i) with a genetically engineered microorganism (gem) able t ... | 1999 | 9872766 |
| polycyclic aromatic hydrocarbon degradation by a new marine bacterium, neptunomonas naphthovorans gen. nov., sp. nov. | two strains of bacteria were isolated from creosote-contaminated puget sound sediment based on their ability to utilize naphthalene as a sole carbon and energy source. when incubated with a polycyclic aromatic hydrocarbon (pah) compound in artificial seawater, each strain also degraded 2-methylnaphthalene and 1-methylnaphthalene; in addition, one strain, nag-2n-113, degraded 2,6-dimethylnaphthalene and phenanthrene. acenaphthene was not degraded when it was used as a sole carbon source but was d ... | 1999 | 9872786 |
| the chlorocatechol-catabolic transposon tn5707 of alcaligenes eutrophus nh9, carrying a gene cluster highly homologous to that in the 1,2,4-trichlorobenzene-degrading bacterium pseudomonas sp. strain p51, confers the ability to grow on 3-chlorobenzoate. | alcaligenes eutrophus (ralstonia eutropha) nh9, isolated in japan, utilizes 3-chlorobenzoate as its sole source of carbon and energy. sequencing of the relevant region of plasmid penh91 from strain nh9 revealed that the genes for the catabolic enzymes were homologous to the genes of the modified ortho-cleavage pathway. the genes from strain nh9 (cbnr-abcd) showed the highest homology (89 to 100% identity at the nucleotide level) to the tcbr-cdef genes on plasmid pp51 of the 1,2,4-trichlorobenzen ... | 1999 | 9925607 |
| molecular characterization of the genes pcag and pcah, encoding protocatechuate 3,4-dioxygenase, which are essential for vanillin catabolism in pseudomonas sp. strain hr199. | pseudomonas sp. strain hr199 is able to utilize eugenol (4-allyl-2-methoxyphenol), vanillin (4-hydroxy-3-methoxybenzaldehyde), or protocatechuate as the sole carbon source for growth. mutants of this strain which were impaired in the catabolism of vanillin but retained the ability to utilize eugenol or protocatechuate were obtained after nitrosoguanidine mutagenesis. one mutant (sk6169) was used as recipient of a pseudomonas sp. strain hr199 genomic library in cosmid pvk100, and phenotypic compl ... | 1999 | 10049847 |
| contrasting effects of a nonionic surfactant on the biotransformation of polycyclic aromatic hydrocarbons to cis-dihydrodiols by soil bacteria. | the biotransformation of the polycyclic aromatic hydrocarbons (pahs) naphthalene and phenanthrene was investigated by using two dioxygenase-expressing bacteria, pseudomonas sp. strain 9816/11 and sphingomonas yanoikuyae b8/36, under conditions which facilitate mass-transfer limited substrate oxidation. both of these strains are mutants that accumulate cis-dihydrodiol metabolites under the reaction conditions used. the effects of the nonpolar solvent 2,2,4, 4,6,8,8-heptamethylnonane (hmn) and the ... | 1999 | 10049904 |
| aspartate 205 in the catalytic domain of naphthalene dioxygenase is essential for activity. | the naphthalene dioxygenase enzyme system carries out the first step in the aerobic degradation of naphthalene by pseudomonas sp. strain ncib 9816-4. the crystal structure of naphthalene dioxygenase (b. kauppi, k. lee, e. carredano, r. e. parales, d. t. gibson, h. eklund, and s. ramaswamy, structure 6:571-586, 1998) indicates that aspartate 205 may provide the most direct route of electron transfer between the rieske [2fe-2s] center of one alpha subunit and mononuclear iron in the adjacent alpha ... | 1999 | 10074076 |
| the periplasmic nitrate reductase in pseudomonas sp. strain g-179 catalyzes the first step of denitrification. | both membrane-bound and periplasmic nitrate reductases have been found in denitrifying bacteria. yet the role of periplasmic nitrate reductase in denitrification has not been clearly defined. to analyze the function of the periplasmic nitrate reductase in pseudomonas sp. strain g-179, the nap gene cluster was identified and found to be linked to genes involved in reduction of nitrite and nitric oxide and anaerobic heme biosynthesis. mutation in the nap region rendered the cells incapable of grow ... | 1999 | 10217771 |
| diverse oxygenations catalyzed by carbazole 1,9a-dioxygenase from pseudomonas sp. strain ca10. | carbazole 1,9a-dioxygenase (cardo) from pseudomonas sp. strain ca10 is a multicomponent enzyme that catalyzes the angular dioxygenation of carbazole, dibenzofuran, and dibenzo-p-dioxin. it was revealed by gas chromatography-mass spectrometry and 1h and 13c nuclear magnetic resonance analyses that xanthene and phenoxathiin were converted to 2,2',3-trihydroxydiphenylmethane and 2,2',3-trihydroxydiphenyl sulfide, respectively. thus, for xanthene and phenoxathiin, angular dioxygenation by cardo occu ... | 1999 | 10322011 |
| monooxygenase-mediated 1,2-dichloroethane degradation by pseudomonas sp. strain dca1. | a bacterial strain, designated pseudomonas sp. strain dca1, was isolated from a 1,2-dichloroethane (dca)-degrading biofilm. strain dca1 utilizes dca as the sole carbon and energy source and does not require additional organic nutrients, such as vitamins, for optimal growth. the affinity of strain dca1 for dca is very high, with a km value below the detection limit of 0.5 microm. instead of a hydrolytic dehalogenation, as in other dca utilizers, the first step in dca degradation in strain dca1 is ... | 1999 | 10347028 |
| identification and sequencing of beta-myrcene catabolism genes from pseudomonas sp. strain m1. | the m1 strain, able to grow on beta-myrcene as the sole carbon and energy source, was isolated by an enrichment culture and identified as a pseudomonas sp. one beta-myrcene-negative mutant, called n22, obtained by transposon mutagenesis, accumulated (e)-2-methyl-6-methylen-2,7-octadien-1-ol (or myrcen-8-ol) as a unique beta-myrcene biotransformation product. this compound was identified by gas chromatography-mass spectrometry. we cloned and sequenced the dna regions flanking the transposon and u ... | 1999 | 10388678 |
| two types of novel dipeptidyl aminopeptidases from pseudomonas sp. strain wo24. | two kinds of dipeptidyl aminopeptidase i (dap i [cathepsin c])-like activities which hydrolyze gly-phe-p-nitroanilide (gly-phe-pna) were detected in pseudomonas sp. strain wo24. they were purified and characterized. the isolated enzymes, named dap bii and dap biii, were revealed to be homogeneous by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) and isoelectric focusing. dap bii was estimated to have a molecular mass of 150,000 da by gel filtration and a subunit size of 73, ... | 1996 | 8892831 |
| degradation of 3-phenoxybenzoic acid in soil by pseudomonas pseudoalcaligenes pob310(ppob) and two modified pseudomonas strains. | pseudomonas pseudoalcaligenes pob310(ppob) and pseudomonas sp. strains b13-d5(pd30.9) and b13-st1(ppob) were introduced into soil microcosms containing 3-phenoxybenzoic acid (3-pob) in order to evaluate and compare bacterial survival, degradation of 3-pob, and transfer of plasmids to a recipient bacterium. strain pob310 was isolated for its ability to use 3-pob as a growth substrate; degradation is initiated by pob-dioxygenase, an enzyme encoded on ppob. strain b13-d5 contains pd30.9, a cloning ... | 1999 | 10427019 |
| heterologous expression and characterization of the purified oxygenase component of rhodococcus globerulus p6 biphenyl dioxygenase and of chimeras derived from it. | in this work, we have purified the his-tagged oxygenase (ht-oxygenase) component of rhodococcus globerulus p6 biphenyl dioxygenase. the alpha or beta subunit of p6 oxygenase was exchanged with the corresponding subunit of pseudomonas sp. strain lb400 or of comamonas testosteroni b-356 to create new chimeras that were purified ht-proteins and designated ht-alpha(p6)beta(p6), ht-alpha(p6)beta(lb400), ht-alpha(p6)beta(b-356), ht-alpha(lb400)beta(p6), and ht-alpha(b-356)beta(p6). ht-alpha(p6)beta(p6 ... | 1999 | 10438748 |
| cloning, sequencing, and expression of isopropylbenzene degradation genes from pseudomonas sp. strain jr1: identification of isopropylbenzene dioxygenase that mediates trichloroethene oxidation. | pseudomonas sp. strain jr1, recently isolated with isopropylbenzene (ipb) as the inducer substrate for trichloroethene (tce) oxidation (b. dabrock, j. riedel, j. bertram, and g. gottschalk, arch. microbiol 158:9-13, 1992), is able to degrade ipb via the meta-cleavage pathway. the genes encoding the first three enzymes in the catabolism of isopropylbenzene were isolated from a genomic library with the broad-host-range cosmid vector pwe15. a 7.6-kb fragment from a 37.7-kb primary cosmid clone was ... | 1996 | 8899984 |
| transcriptional activation of the chlorocatechol degradative genes of ralstonia eutropha nh9. | ralstonia eutropha (formerly alcaligenes eutrophus) nh9 degrades 3-chlorobenzoate via the modified ortho-cleavage pathway. a ca. 5.7-kb six-gene cluster is responsible for chlorocatechol degradation: the cbnabcd operon encoding the degradative enzymes (including orfx of unknown function) and the divergently transcribed cbnr gene encoding the lysr-type transcriptional regulator of the cbn operon. the cbnrab orfxcd gene cluster is nearly identical to the chlorocatechol genes (tcbrcd orfxef) of the ... | 1999 | 10542171 |
| biochemical and genetic analyses of ferulic acid catabolism in pseudomonas sp. strain hr199. | the gene loci fcs, encoding feruloyl coenzyme a (feruloyl-coa) synthetase, ech, encoding enoyl-coa hydratase/aldolase, and aat, encoding beta-ketothiolase, which are involved in the catabolism of ferulic acid and eugenol in pseudomonas sp. strain hr199 (dsm7063), were localized on a dna region covered by two ecori fragments (e230 and e94), which were recently cloned from a pseudomonas sp. strain hr199 genomic library in the cosmid pvk100. the nucleotide sequences of parts of fragments e230 and e ... | 1999 | 10543794 |
| flagellate predation on a bacterial model community: interplay of size-selective grazing, specific bacterial cell size, and bacterial community composition. | the influence of grazing by the bacterivorous nanoflagellate ochromonas sp. strain ds on the taxonomic and morphological structures of a complex bacterial community was studied in one-stage chemostat experiments. a bacterial community, consisting of at least 30 different strains, was fed with a complex carbon source under conditions of low growth rate (0.5 day(-1) when nongrazed) and low substrate concentration (9 mg liter(-1)). before and after the introduction of the predator, the bacterial co ... | 1999 | 10543797 |
| cis-chlorobenzene dihydrodiol dehydrogenase (tcbb) from pseudomonas sp. strain p51, expressed in escherichia coli dh5alpha(ptcb149), catalyzes enantioselective dehydrogenase reactions. | cis-chlorobenzene dihydrodiol dehydrogenase (cdd) from pseudomonas sp. strain p51, cloned into escherichia coli dh5alpha(ptcb149) was able to oxidize cis-dihydrodihydroxy derivatives (cis-dihydrodiols) of dihydronaphthalene, indene, and four para-substituted toluenes to the corresponding catechols. during the incubation of a nonracemic mixture of cis-1,2-indandiol, only the (+)-cis-(1r,2s) enantiomer was oxidized; the (-)-cis-(s,2r) enantiomer remained unchanged. cdd oxidized both enantiomers of ... | 1999 | 10583971 |
| regio- and stereospecific oxidation of fluorene, dibenzofuran, and dibenzothiophene by naphthalene dioxygenase from pseudomonas sp. strain ncib 9816-4. | the regio- and stereospecific oxidation of fluorene, dibenzofuran, and dibenzothiophene was examined with mutant and recombinant strains expressing naphthalene dioxygenase from pseudomonas sp. strain ncib 9816-4. the initial oxidation products were isolated and identified by gas chromatography-mass spectrometry and nuclear magnetic resonance spectrometry. salicylate-induced cells of pseudomonas sp. strain 9816/11 and isopropyl-beta-d-thiogalactopyranoside-induced cells of escherichia coli jm109( ... | 1996 | 8899998 |
| generation of novel bacterial regulatory proteins that detect priority pollutant phenols. | the genetic systems of bacteria that have the ability to use organic pollutants as carbon and energy sources can be adapted to create bacterial biosensors for the detection of industrial pollution. the creation of bacterial biosensors is hampered by a lack of information about the genetic systems that control production of bacterial enzymes that metabolize pollutants. we have attempted to overcome this problem through modification of dmpr, a regulatory protein for the phenol degradation pathway ... | 2000 | 10618218 |
| measurement of minimum substrate concentration (smin) in a recycling fermentor and its prediction from the kinetic parameters of pseudomonas strain b13 from batch and chemostat cultures. | the minimum substrate concentration required for growth, smin, was measured for pseudomonas sp. strain b13 with 3-chlorobenzoate (3cb) and acetate in a recycling fermentor. the substrates were provided alone or in a mixture. smin values predicted with kinetic parameters from resting-cell batches and chemostat cultures differed clearly from the values measured in the recycling fermentor. when 3cb and acetate were fed as single substrates, the measured smin values were higher than the individual s ... | 1996 | 8967775 |
| purification of an extracellular d-(-)-3-hydroxybutyrate oligomer hydrolase from pseudomonas sp. strain a1 and cloning and sequencing of its gene. | an extracellular d-(-)-3-hydroxybutyrate oligomer hydrolase was purified from a poly(3-hydroxybutyrate)-degrading bacterium, pseudomonas sp. strain a1. the purified enzyme hydrolyzed the d-(-)-3-hydroxybutyrate dimer and trimer at similar rates. the enzyme activity was inhibited by a low concentration of diisopropylfluorophosphate. the molecular weight of the hydrolase was estimated to be about 70,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. a 10-kbp dna fragment of a1 was d ... | 1997 | 8981982 |
| substrate specificity of naphthalene dioxygenase: effect of specific amino acids at the active site of the enzyme. | the three-component naphthalene dioxygenase (ndo) enzyme system carries out the first step in the aerobic degradation of naphthalene by pseudomonas sp. strain ncib 9816-4. the three-dimensional structure of ndo revealed that several of the amino acids at the active site of the oxygenase are hydrophobic, which is consistent with the enzyme's preference for aromatic hydrocarbon substrates. although ndo catalyzes cis-dihydroxylation of a wide range of substrates, it is highly regio- and enantiosele ... | 2000 | 10692370 |
| roles of horizontal gene transfer and gene integration in evolution of 1,3-dichloropropene- and 1,2-dibromoethane-degradative pathways. | the haloalkane-degrading bacteria rhodococcus rhodochrous ncimb13064, pseudomonas pavonaceae 170, and mycobacterium sp. strain gp1 share a highly conserved haloalkane dehalogenase gene (dhaa). here, we describe the extent of the conserved dhaa segments in these three phylogenetically distinct bacteria and an analysis of their flanking sequences. the dhaa gene of the 1-chlorobutane-degrading strain ncimb13064 was found to reside within a 1-chlorobutane catabolic gene cluster, which also encodes a ... | 2000 | 10735862 |
| role of tfdc(i)d(i)e(i)f(i) and tfdd(ii)c(ii)e(ii)f(ii) gene modules in catabolism of 3-chlorobenzoate by ralstonia eutropha jmp134(pjp4). | the enzymes chlorocatechol-1,2-dioxygenase, chloromuconate cycloisomerase, dienelactone hydrolase, and maleylacetate reductase allow ralstonia eutropha jmp134(pjp4) to degrade chlorocatechols formed during growth in 2,4-dichlorophenoxyacetate or 3-chlorobenzoate (3-cb). there are two gene modules located in plasmid pjp4, tfdc(i)d(i)e(i)f(i) (module i) and tfdd(ii)c(ii)e(ii)f(ii) (module ii), putatively encoding these enzymes. to assess the role of both tfd modules in the degradation of chloroaro ... | 2000 | 10742248 |