Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| hybrid pathway for chlorobenzoate metabolism in pseudomonas sp. b13 derivatives. | derivatives of pseudomonas sp. b13 which had acquired the capability to utilize 4-chloro- and 3,5-dichlorobenzoate as a consequence of the introduction of genes of the tol plasmid of pseudomonas putida mt-2 were studied. the utilization of these substrates, a property not shared by the parent strains, was shown to depend upon the combined activities of enzymes from the donor and from the recipient. during growth on 3-chloro-, 4-chloro-, and 3,5-dichlorobenzoate, predominantly the toluate 1,2-deo ... | 1980 | 7380800 |
| metabolism of allylglycine and cis-crotylglycine by pseudomonas putida (arvilla) mt-2 harboring a tol plasmid. | spontaneous mutants which acquired the ability to utilize d-allylglycine (d-2-amino-4-pentenoic acid) and dl-cis-crotylglycine (dl-2-amino-cis-4-hexenoic acid) but not l-allylglycine or dl-trans-crotylglycine could be readily isolated from pseudomonas putida mt-2 (pam1). derivative strains of pam1 putatively cured of the tol (pwwo) plasmid were incapable of forming mutants able to utilize the amino acids for growth; however, this ability could be regained by conjugative transfer of the tol (pwwo ... | 1981 | 7287632 |
| isolation and characterization of spontaneously occurring tol plasmid mutants of pseudomonas putida hs1. | a strain of pseudomonas (p. putida hs1) was found to resemble p. putida (arvilla) mt-2 in its ability to degrade toluene, m- and p-xylene, 1,2,4-trimethylbenzene (pseudocumene), and 3-ethyltoluene via oxidation of a methyl substituent and reactions of the meta-fission pathway. the ability to degrade these substrates by p. putida hs1 (ppc1) was shown to be encoded by a tol (pdk1) plasmid as evidenced by: (i) spontaneous loss of the tol-related phenotype after growth with benzoate, (ii) transfer o ... | 1981 | 7240090 |
| tol plasmid pww0 in constructed halobenzoate-degrading pseudomonas strains: prevention of meta pathway. | the hybrid pathway for chlorobenzoate metabolism was studied in wr211 and wr216, which were derived from pseudomonas sp. b13 by acquisition of tol plasmid pww0 from pseudomonas putida mt-2. chlorobenzoates are utilized readily by these strains when meta cleavage of chlorocatechols is suppressed. when wr211 utilizes 3-chlorobenzoate (3cb), the expression of catechol 2,3-dioxygenase (c23o) and the catabolic activities for chloroaromatics via the ortho pathway coexist as a consequence of inactivati ... | 1982 | 7061393 |
| excision and integration of degradative pathway genes from tol plasmid pww0. | wr211 is a transconjugant resulting from transfer of the 117-kilobase (kb) tol degradative plasmid pww0 into pseudomonas sp. strain b13. the plasmid of this strain, pww01211, is 78 kb long, having suffered a deletion of 39 kb. we show that wr211 contains the 39 kb that is missing from its plasmid, together with at least an additional 17 kb of pww0 dna integrated in another part of the genome, probably the chromosome. the ability of wr211 to grow on the tol-specific substrate m-toluate is the res ... | 1982 | 7061392 |
| tol plasmid pww0 in constructed halobenzoate-degrading pseudomonas strains: enzyme regulation and dna structure. | wr211 and wr216 are derivatives of halobenzoate-degrading pseudomonas sp. strain b13 into which the 117-kilobase tol degradative plasmid pww0 has been transferred from pseudomonas putida mt-2. wr211 has lost the ability to grow on the tol-specific substrate m-xylene but retains the ability to grow on its metabolite, m-toluate. an analysis of the induction of enzymes was consistent with wr211 carrying a nonfunctional regulatory gene, xy1r, wr216 is a spontaneous derivative of wr211 which grows on ... | 1982 | 7061391 |
| molecular cloning of tol genes xylb and xyle in escherichia coli. | the xylb and xyle genes in the tol plasmid of pseudomonas putida mt-2, which code for benzyl alcohol dehydrogenase and catechol 2,3-oxygenase, respectively, were cloned onto plasmid pbr322 in escherichia coli for detailed mapping. the xylb gene was mapped in a 2.9-kilobase region within the bamhi bc fragment of ptn2, an in vivo rp4-tol recombinant, whereas the xyle gene was mapped in a 1.8-kilobase region within the bamhi bd fragment. the directions of transcription of these genes were deduced f ... | 1981 | 7009570 |
| molecular and functional analysis of the tol plasmid pwwo from pseudomonas putida and cloning of genes for the entire regulated aromatic ring meta cleavage pathway. | the genetic organization of the pseudomonas putida plasmid pwwo-161, which encodes enzymes for the degradation of toluene and related aromatic hydrocarbons, has been investigated by transposition mutagenesis and gene cloning. catabolic genes were localized to two clusters, one for upper pathway (hydrocarbon leads to carboxylic acid) enzymes and the other for lower pathway (carboxylic acid leads to tricarboxylic acid cycle) enzymes, that are separated by a 14-kilobase dna segment. the physical or ... | 1981 | 6950388 |
| excision of the 40kb segment of the tol plasmid from pseudomonas putida mt-2 involves direct repeats. | 1981 | 6950198 | |
| construction of a partial diploid for the degradative pathway encoded by the tol plasmid (pwwo) from pseudomonas putida mt-2: evidence for the positive nature of the regulation by the xyir gene. | 1980 | 6929031 | |
| molecular cloning of regulatory gene xylr and operator-promoter regions of the xylabc and xyldegf operons of the tol plasmid. | the regulatory gene xylr of the tol plasmid, which functions positively on both xylabc and xyldegf operons in the presence of m-xylene or m-methylbenzyl alcohol, was cloned onto an escherichia coli vector, pacyc177. a fused operon consisting of the operator-promoter region of the xylabc operon and the xyle gene was cloned onto pbr322. the xyle product, catechol 2,3-dioxygenase, was induced by m-xylene or m-methylbenzyl alcohol in the cells containing the fused operon when a 2.8-kilobase segment ... | 1983 | 6885718 |
| complete nucleotide sequence of the metapyrocatechase gene on the toi plasmid of pseudomonas putida mt-2. | metapyrocatechase which catalyzes the oxygenative ring cleavage of catechol to form alpha-hydroxymuconic epsilon-semialdehyde is encoded by the xyle gene on the tol plasmid of pseudomonas putida mt-2. we have cloned the xyle region in escherichia coli and determined the nucleotide sequence of the dna fragment of 985 base pairs around the gene. the fragment included only one open translational frame of sufficient length to accommodate the enzyme. the predicted amino acid sequence consisted of 307 ... | 1983 | 6826546 |
| tol plasmid can prevent induction of chemotactic responses to aromatic acids. | growth conditions that elicited positive chemotaxis to benzoate and m-toluate in tol- pseudomonas putida cells failed to elicit taxis to these compounds in tol+ cells. the inability of tol+ cells to respond to these aromatic acids appears to be due to the preferential expression of tol-encoded genes for aromatic degradation over chromosomally encoded genes. expression of chromosomal genes for aromatic degradation is required for cells to form beta-ketoadipate, the inducer of benzoate and m-tolua ... | 1984 | 6501222 |
| chromogenic identification of genetic regulatory signals in bacillus subtilis based on expression of a cloned pseudomonas gene. | a method to isolate fragments of dna that promote gene expression in bacillus subtilis is described. the system is based on production of catechol 2,3-dioxygenase [cato2ase; catechol:oxygen 2,3-oxidoreductase (decyclizing), ec 1.13.11.2] encoded by the pseudomonas putida tol plasmid gene xyle. the gene was transferred to ab. subtilis/escherichia coli plasmid vector to construct ptg402. although xyle is functionally expressed in e. coli, cato2ase is not detected in b. subtilis unless a fragment o ... | 1983 | 6405380 |
| enzyme recruitment in vitro: use of cloned genes to extend the range of haloaromatics degraded by pseudomonas sp. strain b13. | dna fragments containing the xyld and xyll genes of tol plasmid pww0 -161 of pseudomonas putida, which code for the catabolic enzymes toluate 1,2-dioxygenase and dihydrodihydroxybenzoic acid dehydrogenase, respectively, and the nahg gene of the nah plasmid nah7 , which codes for salicylate hydroxylase, were cloned in pbr322 vector plasmid. deletion and insertion mutagenesis were used to localize these genes with respect to crucial endonuclease cleavage sites. the pbr322-based plasmids were ligat ... | 1984 | 6327621 |
| characterization of a tol-like plasmid from alcaligenes eutrophus that controls expression of a chromosomally encoded p-cresol pathway. | alcaligenes eutrophus wild-type strain 345 metabolizes m- and p-toluate via a catechol meta-cleavage pathway. dna analysis, curing studies, and transfer of this phenotype by conjugation and transformation showed that the degradative genes are encoded on a self-transmissible 85-kilobase plasmid, pra1000. hindiii and xhoi restriction endonuclease analysis of pra1000 showed it to be similar to the archetypal tol plasmid, pwwo, differing in the case of hindiii only by the absence of fragments b and ... | 1984 | 6325399 |
| nucleotide sequence surrounding transcription initiation site of xylabc operon on tol plasmid of pseudomonas putida. | the xylabc operon on the tol plasmid directs the synthesis of enzymes for conversion of toluene to benzoate and is positively controlled by the regulatory gene xylr. in the study here the nucleotide sequence was determined for the regulatory region of this operon. the in vivo transcription initiation site of the operon was determined by s1 nuclease and reverse transcriptase mapping. rna was prepared from m-methylbenzyl alcohol-induced cells of pseudomonas putida and escherichia coli carrying ptn ... | 1984 | 6324212 |
| plasmid-encoded regulation of colicin e1 gene expression. | a plasmid-encoded factor that regulates the expression of the colicin e1 gene was found in molecular cloning experiments. the 2,294-base-pair avaii fragment of the colicin e1 plasmid (cole1) carrying the colicin e1 structural gene and the promoter-operator region had the same information with respect to the repressibility and inducibility of colicin e1 synthesis as the original cole1 plasmid. an operon fusion was constructed between the 204-bp fragment containing the colicin e1 promoter-operator ... | 1983 | 6313603 |
| characterization by molecular cloning of insertion mutants in tol catabolic functions. | a physical and genetic map of the tol catabolic region of pwwo (tol) was obtained by restriction endonuclease analysis of several dna insertion mutants (xyla, xyla xyls, xyls, and xylr) of r plasmid--tol derivatives. in two cases, the inserted dna was shown from restriction, dna hybridization, or heteroduplex analysis of cloned hind iii fragments to originate from within pwwo fragment hind iii-e. the effect of these dna insertions on tol catabolic activity and on structural alterations to the to ... | 1983 | 6304792 |
| identification of chromosomally integrated tol dna in cured derivatives of pseudomonas putida paw1. | some plasmid-free tol- strains derived from pseudomonas putida paw1 (which carries the tol plasmid pww0) have a segment of tol dna located chromosomally. of three independently isolated strains, paw86 had an integrated tol segment of 16 kilobases and paw85 had two copies of this segment in different chromosomal locations, whereas the chromosomal dna of paw82 showed no homology with the tol plasmid. in cultures of the parental strain, it appears that a 56-kilobase tol dna segment is located chrom ... | 1982 | 6290457 |
| spontaneous deletions in the tol plasmid pww20 which give rise to the b3 regulatory mutants of pseudomonas putida mt20. | the size of the tol plasmid pww20 from pseudomonas putida mt20, as measured by analysis of agarose electrophoresis gels after restriction endonuclease hydrolysis, was 270-280 kilobase pairs (kb). during growth on benzoate, mt20 segregates strains carrying mutations in the plasmid regulatory gene xyls; these so-called b3 strains retain the ability to grow on m-xylene (mxy+) but do not grow on its metabolite m-toluate (mtol-) and have also lost the ability to transfer the plasmid (tra-). analysis ... | 1982 | 6288840 |
| plasmid gene organization: naphthalene/salicylate oxidation. | genes for naphthalene metabolism are localized on nah7, an 83-kilobase (kb) plasmid, in two gene clusters under salicylate control. polar mutations formed by insertion of the transposon tn5 permit detection of the transcription direction and the gene organization within two approximately 10-kb dna segments separated by a approximately 7-kb regulatory gene region. the gene cluster specifying conversion of naphthalene to salicylate lies near the left initiation of a 25-kb dna fragment a released b ... | 1982 | 6278499 |
| molecular cloning of gene xyls of the tol plasmid: evidence for positive regulation of the xyldegf operon by xyls. | the xyldegf operon and the regulatory gene xyls of the tol plasmid found in pseudomonas putida mt-2 were cloned onto escherichia coli vector plasmids. a 9.5-kilobase fragment, derived from the tol segment of ptn2 deoxyribonucleic acid, carried the xyl genes d, e, g, and f, which encode toluate oxygenase, catechol 2,3-oxygenase, 2-hydroxymuconic semialdehyde dehydrogenase, and 2-hydroxymuconic semialdehyde hydrolase, respectively. the enzymes were noninducible unless a 3-kilobase psti fragment, d ... | 1981 | 6271729 |
| physical and functional mapping of rp4-tol plasmid recombinants: analysis of insertion and deletion mutants. | cleavage sites for the restriction endonucleases xhoi, bamhi, hindiii, and ecori were mapped on the ptn2 plasmid, a recombinant of tol and rp4, which specifies the toluene-degrading enzymes in the same way as the wild-type tol plasmid. the ptn2 plasmid, purified from a strain of escherichia coli, contained the entire length of the rp4 plasmid (about 54 kilobase pairs [kb]) and the tol segment (about 56 kb). the tol segment is inserted at about 12 and 5 kb away from the ecori and bamhi cleavage s ... | 1980 | 6252192 |
| localization and functional analysis of transposon mutations in regulatory genes of the tol catabolic pathway. | mutant derivatives of the tol plasmid pww0-161, containing tn5 insertions in the xyls and xylr regulatory genes of the catabolic pathway, have been identified and characterized. the two genes are located together on a 1.5- to 3.0-kilobase segment of tol, just downstream of genes of the enzymes of the meta-cleavage pathway. as predicted by a current model for regulation of the tol catabolic pathway, benzyl alcohol dehydrogenase, a representative enzyme of the upper (hydrocarbon leads to carboxyli ... | 1983 | 6188746 |
| [tol-plasmid-specific mrna study]. | 1982 | 6179726 | |
| the tol plasmid is naturally derepressed for transfer. | pseudomonas putida mt-2, formerly known as pseudomonas arvilla mt-2, which carries the wild-type tol plasmid, and p. putida strain ac37 carrying tol, were completely lysed by the pilus-adsorbing plasmid-specific bacteriophages pr4 and prd1. pseudomonas putida strain pps388, also harbouring the plasmid, was not lysed. in a p. putida mt-2 host, tol transferred 18-fold better on a surface (2.5 x 10(-1) transconjugants per donor h-1) than in liquid; when p. putida pps388 was the host, however, a fre ... | 1982 | 6134782 |
| transcription of the tol plasmid toluate catabolic pathway operon of pseudomonas putida is determined by a pair of co-ordinately and positively regulated overlapping promoters. | expression of the meta-cleavage pathway operon of tol plasmid pww0 of pseudomonas putida is positively regulated by the xyls gene product. we have sequenced the promoter region of this operon and localized the transcription initiation sites. two overlapping promoters, designated pm1 and pm2, are responsible for the positively regulated expression of the meta-pathway operon. mutants of p. putida were isolated that expressed the meta-cleavage pathway operon constitutively. several plasmid-located ... | 1984 | 6096122 |
| nucleotide sequence of the promoter region of the xyldegf operon on tol plasmid of pseudomonas putida. | the transcription initiation site of the xyldegf operon on the tol plasmid of pseudomonas putida mt-2 was determined in p. putida and in escherichia coli by s1 nuclease and reverse transcriptase mapping. the induced synthesis of mrna started at the same start point in both p. putida and e. coli, although the amount of mrna in e. coli cells was less than that in p. putida. the nucleotide sequence of the region surrounding the start point was also determined. the ribosome-binding site (rbs) comple ... | 1984 | 6092237 |
| transposon mutagenesis analysis of meta-cleavage pathway operon genes of the tol plasmid of pseudomonas putida mt-2. | hybrid plasmids containing the regulated meta-cleavage pathway operon of tol plasmid pwwo were mutagenized with transposon tn1000 or tn5. the resulting insertion mutant plasmids were examined for their ability to express eight of the catabolic enzymes in escherichia coli. the physical locations of the insertions in each of 28 tn1000 and 5 tn5 derivative plasmids were determined by restriction endonuclease cleavage analysis. this information permitted the construction of a precise physical and ge ... | 1984 | 6090417 |
| metabolism of benzoate and the methylbenzoates by pseudomonas putida (arvilla) mt-2: evidence for the existence of a tol plasmid. | mutant strains of pseudomonas putida (arvilla) mt-2 which have lost the ability to grow at the expense of m- or p-toluate (methylbenzoate) but retain the ability to grow with benzoate arise spontaneously during growth on benzoate; this genetic loss occurs to a lesser extent during growth on nonaromatic carbon sources in the presence of mitomycin c. the mutants have totally lost the activity of the enzymes of the divergent meta pathway with the possible exception of 2-oxopent-4-enoate hydratase a ... | 1974 | 4418209 |
| tol plasmid pww15 contains two nonhomologous, independently regulated catechol 2,3-oxygenase genes. | pseudomonas putida mt15 contains a 250-kilobase-pair (kbp) tol plasmid pww15, encoding toluene and xylene catabolism, which undergoes large spontaneous deletions to give two classes of mutants with altered catabolic phenotypes (h. keil and p. a. williams, j. gen. microbiol, 131:1023-1033, 1985). two structural genes for catechol 2,3-oxygenase (c23o) were cloned from pww15. the gene for c23oi was located on the 2.1-kbp xhoi fragment xh, whereas that for c23oii was found on the 11.5-kbp bamhi frag ... | 1985 | 4008443 |
| application of dna-dna colony hybridization to the detection of catabolic genotypes in environmental samples. | the application of preexisting dna hybridization techniques was investigated for potential in determining populations of specific gene sequences in environmental samples. cross-hybridizations among two degradative plasmids, tol and nah, and two cloning vehicles, plafr1 and rsf1010, were determined. the detection limits for the tol plasmid against a nonhomologous plasmid-bearing bacterial background was ascertained. the colony hybridization technique allowed detection of one colony containing tol ... | 1985 | 4004244 |
| use of cloned genes of pseudomonas tol plasmid to effect biotransformation of benzoates to cis-dihydrodiols and catechols by escherichia coli cells. | dna fragments containing the xyld and xyll genes, which specify the broad-specificity enzymes toluate-1,2-dioxygenase and 3,5-cyclohexadiene-1,2-diol-1-carboxylic acid dehydrogenase, respectively, of tol plasmid pww0-161 of pseudomonas putida have previously been cloned in the pbr322 vector plasmid (p.r. lehrbach, j. zeyer, w. reinecke, h.-j. knackmuss, and k. n. timmis, j. bacteriol. 158:1025-1032, 1984). in this study, escherichia coli cells containing hybrid plasmids carrying the cloned xyld ... | 1985 | 3911905 |
| identification of the promoter of the pseudomonas gene coding for carboxypeptidase g2. | a 213-bp region of noncoding dna upstream of the atg start codon of the pseudomonas carboxypeptidase g2 (cpg2) structural gene has been shown to contain the cpg2 promoter. the mrna start point (+1) on the dna sequence has been identified by mapping the 5' end of the cpg2 transcript. the identified promoter region contains a -10 region (tataag) that closely resembles the escherichia coli consensus sequence (tataat), but has no easily recognisable -35 region. the lack of homology in the -35 region ... | 1985 | 3839252 |
| adaptation of pseudomonas putida mt-2 to growth on aromatic amines. | pseudomonas putida mt-2 (atcc 33015) carrying the tol plasmid pww0 could adapt to growth on the aromatic amines aniline and m- and p-toluidine. in strain ucc2, a derivative adapted to rapid growth on these compounds, they were oxidatively deaminated to catechol or 4-methylcatechol, which in turn were dissimilated by a meta-cleavage pathway. the aniline/toluidine oxygenase and the meta-cleavage pathway enzymes were inducible by aromatic amines. evidence is presented that in strain ucc2, plasmid p ... | 1986 | 3794647 |
| chromosomal location of tol plasmid dna in pseudomonas putida. | the soil isolate pseudomonas putida mw1000 can grow on toluene and other hydrocarbons; in this respect it is similar to strains of pseudomonas which carry the tol plasmid. by conjugation experiments, the genes conferring these growth abilities have been shown to be located on the bacterial chromosome, linked to vil and catb. a 56-kilobase segment of the bacterial chromosome of mw strains carrying the tol genes can transpose to the incp-1 plasmid r18-18. physical analysis of these tol r18-18 hybr ... | 1986 | 3782038 |
| identification of cis-diols as intermediates in the oxidation of aromatic acids by a strain of pseudomonas putida that contains a tol plasmid. | pseudomonas putida bg1 was isolated from soil by enrichment with p-toluate and selection for growth with p-xylene. other hydrocarbons that served as growth substrates were toluene, m-xylene, 3-ethyltoluene, and 1,2,4-trimethylbenzene. the enzymes responsible for growth on these substrates are encoded by a large plasmid with properties similar to those of tol plasmids isolated from other strains of pseudomonas. treatment of p. putida bg1 with nitrosoguanidine led to the isolation of a mutant stra ... | 1986 | 3711022 |
| the effect of lipophilic weak acids on the segregational stability of tol plasmids in pseudomonas putida. | the effect of various lipophilic weak acids on the stability of certain tol plasmids was investigated. benzoate induced deletion of tol plasmid dna in pseudomonas putida mt15, followed by loss of the plasmid; this effect was ph- and concentration-dependent, suggesting that undissociated benzoic acid was a more effective curing agent than the benzoate anion. plasmid loss always approached a frequency of 100% after a lag and apparently depended on the prior occurrence of deletions, although delete ... | 1987 | 3668501 |
| nucleotide sequence and expression of gene nahh of plasmid nah7 and homology with gene xyle of tol pwwo. | the enzyme catechol 2,3-dioxygenase (c23o) encoded by the nahh gene of plasmid nah7 converts catechol to alpha-hydroxymuconic epsilon-semialdehyde in pseudomonas putida. we have cloned this structural gene into vectors puc18 and pkt240, determined the nucleotide sequence and deduced the amino acid sequence. in comparison to the gene xyle of the tol plasmid pwwo which encodes a similar c230 enzyme [nakai et al. j. biol. chem. (1983b), 2923-2928], the respective g + c contents were 55% and 57%, th ... | 1987 | 3623105 |
| overproduction of the xyls gene product and activation of the xyldlegf operon on the tol plasmid. | the effect of high-level expression of the regulatory gene xyls of the pseudomonas putida tol plasmid on the activation of the xyldlegf operon was investigated in escherichia coli. the xyls gene was placed downstream from the tac promoter, and the resultant fusion was cloned in cis to the xyldlegf operon. the expression of the operon was monitored by the level of catechol 2,3-dioxygenase, whose structural gene xyle was placed directly after the operator-promoter region of xyldlegf. xyls transcri ... | 1987 | 3611023 |
| roles of the divergent branches of the meta-cleavage pathway in the degradation of benzoate and substituted benzoates. | the tol plasmid-specified meta-cleavage pathway for the oxidative catabolism of benzoate and toluates branches at the ring cleavage products of catechols and reconverges later at 2-oxopent-4-enoate or its corresponding substituted derivatives. the hydrolytic branch of the pathway involves the direct formation of 2-oxopent-4-enoate or its derivatives, whereas the oxalocrotonate branch involves three enzymatic steps effected by a dehydrogenase, an isomerase, and a decarboxylase, which produce the ... | 1987 | 3542963 |
| vector for regulated expression of cloned genes in a wide range of gram-negative bacteria. | a pkt231-based broad-host-range plasmid vector was constructed which enabled regulation of expression of cloned genes in a wide range of gram-negative bacteria. this vector, pnm185, contained upstream of its ecori, ssti, and sstii cloning sites the positively activated pm twin promoters of the tol plasmid and xyls, the gene of the positive regulator of these promoters. expression of cloned genes was induced with micromolar quantities of benzoate or m-toluate, the inexpensive coinducers of the pm ... | 1986 | 3525513 |
| the xylabc promoter from the pseudomonas putida tol plasmid is activated by nitrogen regulatory genes in escherichia coli. | the xylabc promoter (op1), located on the tol plasmid of pseudomonas putida contains sequences homologous to the conserved regions found in nitrogen fixation (nif) promoters and in other promoters subject to nitrogen control. xyla-lac fusions were constructed in order to monitor expression from the op1 promoter in escherichia coli. transcription was activated in the presence of the heterologous regulatory genes ntrc or nifa from klebsiella pneumoniae as well as by the homologous p. putida regula ... | 1986 | 3520241 |
| evolutionary relationships between catabolic pathways for aromatics: conservation of gene order and nucleotide sequences of catechol oxidation genes of pww0 and nah7 plasmids. | tol plasmid pww0 and plasmid nah7 encode catabolic enzymes required for oxidative degradation of toluene and naphthalene, respectively. the gene order of the catabolic operon of nah7 for salicylate oxidation was determined to be: promoter--nahg (the structural gene for salicylate hydroxylase)--nahh (catechol 2.3-dioxygenase)--nahi (hydroxymuconic semialdehyde dehydrogenase)--nahn (hydroxymuconic semialdehyde hydrolase)--nahl (2-oxopent-4-enoate hydratase). this order is identical to that of the ... | 1987 | 3481421 |
| the xyls gene positive regulator of tol plasmid pwwo: identification, sequence analysis and overproduction leading to constitutive expression of meta cleavage operon. | the pseudomonas putida tol plasmid pwwo carries an operon that specifies a meta-cleavage pathway for the catabolism of benzoate and toluates whose transcription is positively regulated by the xyls gene product. stimulation of transcription of the operon is thought to result from activation of this protein by pathway substrates/effectors. in the present study, overexpression of the xyls gene has led to identification of the regulator as a 33 kda protein. overexpression of xyls also resulted in pa ... | 1987 | 3475526 |
| redesigning metabolic routes: manipulation of tol plasmid pathway for catabolism of alkylbenzoates. | increasing quantities of man-made organic chemicals are released each year into the biosphere. some of these compounds are both toxic and relatively resistant to physical, chemical, or biological degradation, and they thus constitute an environmental burden of considerable magnitude. genetic manipulation of microbial catabolic pathways offers a powerful means by which to accelerate evolution of biodegradative routes through which such compounds might be eliminated from the environment. in the ex ... | 1987 | 3468623 |
| regulatory circuits controlling transcription of tol plasmid operon encoding meta-cleavage pathway for degradation of alkylbenzoates by pseudomonas. | tol plasmid pwwo of pseudomonas putida contains two operons that specify a pathway for the degradation of aromatic hydrocarbons. the 'upper' operon encodes enzymes for the oxidation of toluene to benzoate and xylenes to toluates, whereas the meta-cleavage operon specifies the further oxidation of benzoate and toluates. transcription of the upper pathway operon is positively regulated by the xylr protein, which is activated by toluene/xylenes and their alcohol catabolic products, in combination w ... | 1987 | 3448461 |
| transfer and expression of mesophilic plasmid-mediated degradative capacity in a psychrotrophic bacterium. | a psychrotrophic bacterium, originally isolated from a natural aquatic environment, was characterized and identified as pseudomonas putida q5 for use as a representative recipient for biodegradative genes from a mesophilic microorganism. the tol plasmid pwwo of the mesophile p. putida paw1 was successfully transferred by conjugation to the naturally isolated psychrotroph p. putida q5, as shown by plasmid analysis by agarose gel electrophoresis. expression of the genes encoded by the mesophilic t ... | 1988 | 3377489 |
| bacterial metabolism of side chain fluorinated aromatics: cometabolism of 3-trifluoromethyl(tfm)-benzoate by pseudomonas putida (arvilla) mt-2 and rhodococcus rubropertinctus n657. | the tol plasmid-encoded enzymes of the methylbenzoate pathway in pseudomonas putida mt-2 cometabolized 3-trifluoromethyl (tfm)-benzoate. two products, 3-tfm-1,2-dihydroxy-2-hydrobenzoate (3-tfm-dhb) and 2-hydroxy-6-oxo-7,7,7-trifluoro-hepta-2,4-dienoate (7-tfhod) were identified chemically and by spectroscopic properties. tfm-substituted analogues of the metabolites of the methylbenzoate pathway were generally converted at drastically reduced rates. the catechol-2,3-dioxygenase from pseudomonas ... | 1988 | 3365096 |
| molecular analysis of regulatory and structural xyl genes of the tol plasmid pww53-4. | pww53-4 is a cointegrate between rp4 and the catabolic plasmid pww53 from pseudomonas putida mt53, which contains 36 kbp of pww53 dna inserted close to the oriv gene of rp4; it encodes the ability to grow on toluene and the xylenes, characteristic of pww53, as well as resistance to tetracycline, kanamycin and carbenicillin, characteristic of rp4. a physical map of the 36 kbp insert of pww53 dna for 11 restriction enzymes is presented, showing that the relative positions of the two xyl operons ar ... | 1987 | 3309179 |
| activation of the xyldlegf promoter of the tol toluene-xylene degradation pathway by overproduction of the xyls regulatory gene product. | the xyls regulatory gene of the pseudomonas putida tol plasmid (pwwo) has been cloned under the transcriptional control of the escherichia coli tac promoter in a broad-host-range controlled-expression vector. induction with isopropylthiogalactoside allowed overproduction and characterization of the xyls product by specific interaction with the tol meta-cleavage pathway operator-promoter region (op2) in vivo in e. coli. examination of plasmid-specified polypeptides in e. coli maxicells led to ide ... | 1987 | 3301806 |
| a bacteriophage t4 expression cassette that functions efficiently in a wide range of gram-negative bacteria. | we have constructed a derivative of the broad-host-range vector rsf1010. this plasmid, p alpha omega, contains an expression cassette derived from bacteriophage t4 gene 32, into which we have inserted the coding sequence for the xyle enzyme (c2,3o) of the tol plasmid pwwo. the composite plasmid, p alpha xyle omega, was transferred by conjugal mobilisation into a variety of gram-negative bacteria (agrobacter, paracoccus, erwinia, pseudomonas, rhizobium and xanthomonas). high levels of c2,3o activ ... | 1988 | 3259198 |
| comparison of the meta pathway operons on nah plasmid pww60-22 and tol plasmid pww53-4 and its evolutionary significance. | the regulated meta pathway operon for the catabolism of salicylate on the naphthalene plasmid pww60-22 was cloned into the broad-host-range vector pkt230 on a 17.5 kbp bamhi fragment. the recombinant plasmid conferred the ability to grow on salicylate when mobilized into plasmid-free pseudomonas putida paw130. a detailed restriction map of the insert was derived and the locations of some of the genes were determined by subcloning and assaying for their gene products in escherichia coli and p. pu ... | 1988 | 3254935 |
| loss of the toluene-xylene catabolic genes of tol plasmid pww0 during growth of pseudomonas putida on benzoate is due to a selective growth advantage of 'cured' segregants. | during growth on benzoate-minimal medium pseudomonas putida mt-2 (paw1) segregates derivative ('cured') strains which have lost the ability to use the pathway encoded by its resident catabolic plasmid pww0. experiments with two plasmids identical to pww0 but each with an insert of tn401, which confers resistance to carbenicillin, suggested that the 'benzoate curing' occurs far more frequently by the specific deletion of the 39 kbp region carrying the catabolic genes than by total plasmid loss. t ... | 1988 | 3246596 |
| nucleotide sequence of the regulatory gene xylr of the tol plasmid from pseudomonas putida. | we have determined the nucleotide sequence of the xylr gene for a transcriptional activator for the degradative pathway of aromatic hydrocarbons on the tol plasmid from pseudomonas putida. the 1698-bp sequence for a 566-amino acid (aa) protein (mr 63741) was identified as the xylr-encoding sequence. three regions in xylr show homology to klebsiella pneumoniae ntrc and nifa, both of which are transcriptional activators for the ntr and nif genes involved in the nitrogen metabolism. the central reg ... | 1988 | 3169574 |
| broad-host range expression vectors containing manipulated meta-cleavage pathway regulatory elements of the tol plasmid. | the construction of perd20 and perd21, two broad-host range expression vectors, is described. the vectors contain the pm promoter of the meta-cleavage pathway operon of the tol plasmid pwwo; this promoter is present within a polylinker which provides a number of downstream cloning sites close to the transcription initiation site. transcription from the pm promoter in these vectors is controlled not by the natural positive regulator of pm, the xy1s protein, but by an xy1s mutant analogue, xy1s2tr ... | 1988 | 3123271 |
| physical and functional mapping of two cointegrate plasmids derived from rp4 and tol plasmid pdk1. | cointegrate plasmids were formed in vivo between the broad-host-range r-plasmid rp4 and two catabolic plasmids derived from pseudomonas putida hs1. one of these was the wild-type plasmid pdk1 encoding the complete inducible toluene/xylene (tol) catabolic pathway and one was pdkt1, a deletion derivative of pdk1 selected after growth of hs1 on benzoate and supporting growth on only toluene. the two plasmids formed, pdk2 and pdkt2 respectively, each consisted of a complete rp4 replicon in which was ... | 1988 | 3076182 |
| the presence of two complete homologous meta pathway operons on tol plasmid pww53. | pww53 is a 110 kbp catabolic plasmid which encodes the complete pathway for the utilization of toluene and the xylenes. the upper pathway operon xylcab is located between two homologous but distinct meta pathway operons, xyldlegf(i,j,k)h, which are in direct repeat. these have each been cloned on large hindiii restriction fragments ha (17.5 kbp) and hb (15.6 kbp), the restriction sites of which have been mapped. during growth of mt53 on benzoate, mutants which have lost the ability to grow on hy ... | 1988 | 3076178 |
| gene organization of the first catabolic operon of tol plasmid pww53: production of indigo by the xyla gene product. | the entire operon coding for the enzymes responsible for conversion of toluenes to benzoates has been cloned from tol plasmid pww53 and the position of the genes accurately located. the coding region was 7.4 kilobase pairs (kbp) long, and the gene order was operator-promoter region (op1)-a small open reading frame-xylc (1.6 kbp)-xyla (2.9 kbp)-xylb (1.8 kbp). within the coding region there was considerable homology with the isofunctional region of the archetypal tol plasmid pww0. a central regio ... | 1987 | 3027047 |
| naturally occurring tol plasmids in pseudomonas strains carry either two homologous or two nonhomologous catechol 2,3-oxygenase genes. | structural genes for catechol 2,3-oxygenase (c23o) were cloned from the tol plasmids pww5, pww14, pww74, pww84, and pww88 isolated from pseudomonas strains of diverse geographical origins. each pkt230-based c23o+ recombinant plasmid carried a 2.05-kilobase xhoi insert which showed strong homology in southern hybridizations with the xyle gene from the archetype tol plasmid pww0. fragments were mapped for restriction endonuclease sites and were classified into two closely related groups on the bas ... | 1986 | 3023288 |
| nucleotide sequence of the regulatory gene xyls on the pseudomonas putida tol plasmid and identification of the protein product. | the xyls gene is a regulatory gene which positively controls expression of the genes on the tol plasmid for degradation enzymes of benzoate or m-toluate in pseudomonas putida. cloning of the gene in escherichia coli and determination of the nucleotide sequence revealed an open reading frame of 963 bp which corresponds to a protein with an mr of 36,502. the xyls gene was recloned onto a tac-promoter vector, and the product was identified by the maxicell procedure as a protein with an approximate ... | 1986 | 3023186 |
| altered effector specificities in regulators of gene expression: tol plasmid xyls mutants and their use to engineer expansion of the range of aromatics degraded by bacteria. | stimulation of transcription from positively regulated promoters involves regulatory proteins that have been activated, generally as a consequence of binding low molecular weight effector molecules. to define essential structural features of effectors for one positively acting gene regulator, the xyls-encoded protein, which activates the tol plasmid meta-cleavage pathway operon promoters, effector activities of a wide range of benzoate derivatives have been systematically analyzed, and mutant xy ... | 1986 | 3022293 |
| gene order of the tol catabolic plasmid upper pathway operon and oxidation of both toluene and benzyl alcohol by the xyla product. | tol plasmid pww0 specifies enzymes for the oxidative catabolism of toluene and xylenes. the upper pathway converts the aromatic hydrocarbons to aromatic carboxylic acids via corresponding alcohols and aldehydes and involves three enzymes: xylene oxygenase, benzyl alcohol dehydrogenase, and benzaldehyde dehydrogenase. the synthesis of these enzymes is positively regulated by the product of xylr. determination of upper pathway enzyme levels in bacteria carrying tn5 insertion mutant derivatives of ... | 1986 | 3015870 |
| nucleotide sequence of a dna segment promoting transcription in pseudomonas putida. | a dna segment that promotes gene expression in pseudomonas putida was identified in ptn8, a mutant plasmid of an rp4-tol recombinant. a promoter on the segment was cloned with a promoter-probe vector containing the xyle gene of the tol plasmid. the xyle gene was expressed under the control of the promoter, and the gene product catechol 2,3-dioxygenase was constitutively synthesized. as analyzed by an s1 nuclease protection assay, the amount of mrna produced in p. putida was more than that in esc ... | 1986 | 3011741 |
| genetic analysis of a relaxed substrate specificity aromatic ring dioxygenase, toluate 1,2-dioxygenase, encoded by tol plasmid pww0 of pseudomonas putida. | toluate 1,2-dioxygenase is the first enzyme of a meta-cleavage pathway for the oxidative catabolism of benzoate and substituted benzoates to krebs cycle intermediates that is specified by tol plasmid pww0 of pseudomonas putida. a collection of derivatives harbouring tn1000 insertions and defective in toluate dioxygenase have been isolated from ppl392, a pbr322-based hybrid plasmid carrying the tol plasmid meta-cleavage pathway operon. in parallel, a series of n-methyl-n'-nitro-n-nitro-soguanidin ... | 1986 | 3010045 |
| homology between nucleotide sequences of promoter regions of nah and sal operons of nah7 plasmid of pseudomonas putida. | the in vivo transcription start sites of the nah and sal operons of the nah7 plasmid were determined by s1 nuclease mapping and the nucleotide sequence surrounding these transcription start sites was determined. since expression of both of these operons is coordinately controlled by the product of the transcriptional activator gene nahr, the sequences were compared to locate potential sites involved in common regulation. in the 100-base-pair region preceding transcription start sites of both ope ... | 1986 | 3001734 |
| omega mutagenesis in gram-negative bacteria: a selectable interposon which is strongly polar in a wide range of bacterial species. | we have used the 2.0-kb dna fragment omega [prentki and krisch, gene 29 (1984) 303-313] to mutagenize in vitro a broad-host-range plasmid carrying the entire meta-cleavage pathway of the pseudomonas putida tol plasmid pww0. the mutant plasmids were subsequently introduced by conjugal mobilization into a variety of gram-negative bacteria. the omega fragment carries a selectable marker (aada+; spcr/smr), which is expressed in all species tested, as well as flanking transcription and translation te ... | 1985 | 2998930 |
| evolutionary conservation of genes coding for meta pathway enzymes within tol plasmids pww0 and pww53. | pseudomonas putida mt53 contains a tol plasmid, pww53, that encodes toluene-xylene catabolism. pww53 is nonconjugative, is about 105 to 110 kilobase pairs (kbp) in size, and differs significantly in its restriction endonuclease digestion pattern and incompatibility group from the archetypal tol plasmid pww0. an rp4::pww53 cointegrate plasmid, pww53-4, containing about 35 kbp of pww53 dna, including the entire catabolic pathway genes, was formed, and a restriction map for kpni, hindiii, and bamhi ... | 1985 | 2997136 |
| determination of the transcription initiation site and identification of the protein product of the regulatory gene xylr for xyl operons on the tol plasmid. | the xylr gene is a regulatory gene on the tol plasmid, which acts in a positive manner on xyl operons for degradation of toluene and xylenes in pseudomonas putida. a dna fragment containing the xylr promoter region was cloned on promoter-probing vectors, and its nucleotide sequence was determined. the transcription initiation site of the xylr gene was determined in cells of p. putida and escherichia coli by s1 nuclease and reverse transcriptase mapping. two initiation sites were detected which w ... | 1985 | 2993247 |
| positive regulation and transcription initiation of xyl operons on tol plasmid. | 1985 | 2990420 | |
| identification and characterization of tn4653, a transposon covering the toluene transposon tn4651 on tol plasmid pww0. | a pseudomonas tol plasmid pww0 possesses toluene degradative pathway (xyl) genes. unstable maintenance of a pww0 derivative in escherichia coli allowed us to identify two transposable elements each carrying all the xyl genes. one element corresponded to a 56 kb transposon, tn4651, which we had previously characterized. the other element newly identified in this study was 70 kb long, and this element, designated tn4653, completely included tn4651. genetic analysis of tn4653 demonstrated that its ... | 1988 | 2851712 |
| benzoate-dependent induction from the op2 operator-promoter region of the tol plasmid pwwo in the absence of known plasmid regulatory genes. | expression of the lower catabolic pathway of the tol plasmid pwwo requires an aromatic acid inducer and the product of the xyls regulatory gene. pseudomonas putida cells transformed with a plasmid containing the operator-promoter region of the lower pathway (op2 [or pm]), upstream from the catechol 2,3-dioxygenase structural gene, showed enzyme induction in the absence of known tol plasmid regulatory genes. induction was not seen in transformed escherichia coli cells or in a p. putida mutant lac ... | 1988 | 2841300 |
| genetic analysis of a transposon carrying toluene degrading genes on a tol plasmid pww0. | toluene degrading (xyl) genes on a pseudomonas tol plasmid pww0 are located within a 39-kb dna portion. the 56-kb region including these xyl genes and its 17-kb derivative with a deletion of the internal 39-kb portion transposed to various sites on target replicons such as pacyc184 and r388 in escherichia coli reca strains. thus the 56- and 17-kb regions were designated tn4651 and tn4652, respectively. genetic analysis of tn4652 demonstrated that its transposition occurs by a two-step process, n ... | 1987 | 2830457 |
| degradation of phenol and m-toluate in pseudomonas sp. strain est1001 and its pseudomonas putida transconjugants is determined by a multiplasmid system. | the utilization of phenol, m-toluate, and salicylate (phe+, mtol+, and sal+ characters, respectively) in pseudomonas sp. strain est1001 is determined by the coordinated expression of genes placed in different plasmids, i.e., by a multiplasmid system. the natural multiplasmid strain est1001 is phenotypically unstable. in its phe-, mtol-, and sal- segregants, the plasmid dna underwent structural rearrangements without a marked loss of plasmid dna, and the majority of segregants gave revertants. th ... | 1989 | 2768199 |
| cloning and sequence analysis of the ntra (rpon) gene of pseudomonas putida. | the gene encoding a sigma factor ntra (rpon) was cloned from pseudomonas putida by cross-hybridization with a probe containing a part of the corresponding escherichia coli gene. the cloned gene complemented an ntra mutation of e. coli in activation of xyl genes on the tol plasmid. the predicted amino acid (aa) sequence of p. putida ntra (497 aa; mr 56,215) is highly homologous to ntra proteins from azotobacter vinelandii (81.7%), klebsiella pneumoniae (52.6%), and rhizobium meliloti (36.1%). the ... | 1989 | 2695395 |
| 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 ... | 1989 | 2687253 |
| physically associated enzymes produce and metabolize 2-hydroxy-2,4-dienoate, a chemically unstable intermediate formed in catechol metabolism via meta cleavage in pseudomonas putida. | the meta-cleavage pathway of catechol is a major mechanism for degradation of aromatic compounds. in this pathway, the aromatic ring of catechol is cleaved by catechol 2,3-dioxygenase and its product, 2-hydroxymuconic semialdehyde, is further metabolized by either a hydrolytic or dehydrogenative route. in the dehydrogenative route, 2-hydroxymuconic semialdehyde is oxidized to the enol form of 4-oxalocrotonate by a dehydrogenase and then further metabolized to acetaldehyde and pyruvate by the act ... | 1989 | 2681159 |
| involvement of pseudomonas putida rpon sigma factor in regulation of various metabolic functions. | the rpon protein was originally identified in escherichia coli as a sigma (sigma) factor essential for the expression of nitrogen regulons. in the present study we cloned the pseudomonas putida rpon gene and identified its gene product as a protein with an apparent molecular weight of 78,000. a mutant rpon gene was constructed by in vitro insertion mutagenesis with a kanamycin cassette. a p. putida rpon mutant was then isolated by replacement of the intact chromosomal rpon gene by the mutant rpo ... | 1989 | 2666396 |
| nucleotide sequence and expression of the catechol 2,3-dioxygenase-encoding gene of phenol-catabolizing pseudomonas cf600. | pseudomonas cf600 degrades phenol and some of its methylated derivatives via a plasmid-encoded catabolic pathway. the catechol 2,3-dioxygenase (c23o) enzyme of this pathway catalyses the conversion of catechol to 2-hydroxymuconic semialdehyde. we have determined the nucleotide (nt) sequence of the dmpb structural gene for this enzyme, and expressed and identified its polypeptide product in escherichia coli. the xyle gene of tol plasmid pwwo and the nahh gene of plasmid nah7 encode analogous c23o ... | 1989 | 2620833 |
| molecular analysis of a plasmid-encoded phenol hydroxylase from pseudomonas cf600. | pseudomonas strain cf600 is able to utilize phenol and 3,4-dimethylphenol as sole carbon and energy source. we demonstrate that growth on these substrates is by virtue of plasmid-encoded phenol hydroxylase and a meta-cleavage pathway. screening of a genomic bank, with dna from the previously cloned catechol 2,3-dioxygenase gene of the tol plasmid pww0, was used in the identification of a clone which could complement a phenol-hydroxylase-deficient transposon insertion mutant. deletion mapping and ... | 1989 | 2559941 |
| characterization of five genes in the upper-pathway operon of tol plasmid pww0 from pseudomonas putida and identification of the gene products. | the upper operon of the tol plasmid pww0 of pseudomonas putida encodes a set of enzymes which transform toluene and xylenes to benzoate and toluates. the genetic organization of the operon was characterized by cloning of the upper operon genes into an expression vector and identification of their products in escherichia coli maxicells. this analysis showed that the upper operon contains at least five genes in the order of xylc-xylm-xyla-xylb-xyln. between the promoter of the operon and xylc, the ... | 1989 | 2549010 |
| a simple procedure for transferring genes cloned in escherichia coli vectors into other gram-negative bacteria: phenotypic analysis and mapping of tol plasmid gene xylk. | a simple method to transfer non-conjugative escherichia coli plasmids to other gram-negative bacteria and their maintenance is described. this method involves generation of inverse transposition-mediated cointegrates of the non-conjugative e. coli plasmid with a conjugative incw broad-host-range plasmid, r388, carrying tn10. isolation of such cointegrates was readily effected by conjugal transfer from an e. coli donor containing the two plasmids to an e. coli recipient, with selection for transc ... | 1989 | 2548929 |
| expression of the regulatory gene xyls on the tol plasmid is positively controlled by the xylr gene product. | the regulatory gene xyls on the tol plasmid of pseudomonas putida activates the transcription of the xyldlegf operon for the m-toluate-degrading pathway in the presence of m-toluate. the gene also activates the transcription of the same operon in the presence of m-xylene or m-methylbenzyl alcohol, but for this activation another regulatory gene, xylr, is required. in this study we examined the xyls expression by determining the mrna by reverse transcriptase mapping and by monitoring the enzyme a ... | 1987 | 2440045 |
| genetic, functional and sequence analysis of the xylr and xyls regulatory genes of the tol plasmid pww0. | mutant derivatives of a plasmid, pcf20, which carries the xhoi-d fragment of the tol plasmid pww0 have been isolated using tn5 transposon mutagenesis. insertion mutations of the xylr and xyls regulatory genes of the catabolic pathway have been isolated and characterized and their ability to induce catechol 2,3-oxygenase activity determined. analysis of the insertion mutants and also segments of the xhoi-d fragment cloned into plasmid puc8 in maxicells has identified a 68 kda polypeptide product ... | 1986 | 2430049 |
| signal-regulator interactions. genetic analysis of the effector binding site of xyls, the benzoate-activated positive regulator of pseudomonas tol plasmid meta-cleavage pathway operon. | this study reports a genetic analysis of the interactions between a positive regulator of gene expression and its effector molecules. transcription of the tol plasmid meta-cleavage pathway operon is specifically stimulated by the xyls protein positive regulator either through activation of this regulator by benzoate effectors or through its hyperproduction. one xyls mutant that exhibits constitutive expression of the operon promoter has been characterized, together with six mutants encoding alte ... | 1990 | 2407853 |
| location and organization of the dimethylphenol catabolic genes of pseudomonas cf600. | the gene organization of the phenol catabolic pathway of pseudomonas cf600 has been investigated. this strain can grow on phenol and some methylated phenols by virtue of an inducible phenol hydroxylase and metacleavage pathway enzymes. the genes coding for these enzymes are located on pvi150, an incp-2 degradative mega plasmid of this strain. twenty-three kilobases of contiguous dna were isolated from lambda libraries constructed from strains harbouring wild type and tn5 insertion mutants of pvi ... | 1990 | 2325624 |
| biotransformation of substituted benzoates to the corresponding cis-diols by an engineered strain of pseudomonas oleovorans producing the tol plasmid-specified enzyme toluate-1,2-dioxygenase. | the conversion of substituted benzoates into 1,2-cis-dihydroxycyclohexa-3,5-diene carboxylic acids (cis-diols) was effected by using escherichia coli and pseudomonas recombinants carrying the xylxyz genes originating from the pseudomonas putida mt-2 tol plasmid, thus producing toluate-1,2-dioxygenase. pseudomonas oleovorans gpo12 recombinants readily produced meta- and para-substituted cis-diols, but were limited in their oxidation of ortho-substituted substrates. | 1990 | 2306096 |
| promoter-upstream activator sequences are required for expression of the xyls gene and upper-pathway operon on the pseudomonas tol plasmid. | stimulation of transcription from the pseudomonas tol plasmid xyls gene promoter (ps) and the upper-pathway operon promoter (pu) is dependent on the positive regulator protein xylr activated by an effector molecule such as 3-cholorotoluene, and on rpon, an rna polymerase sigma factor. mutational analysis of the ps and pu promoters showed that upstream activator sequences located between -110 and -218bp upstream of the main transcription initiation point are required for regulated expression from ... | 1990 | 2287278 |
| construction of hybrid xyle genes between the two duplicate homologous genes from tol plasmid pww53: comparison of the kinetic properties of the gene products. | the two xyle genes for catechol 2,3-oxygenase, encoded by tol plasmid pww53, carry a common sali restriction site within the reading frame. each gene was cut at the sali site and the 5' end of each gene spliced to the 3' end of the other to form hybrid genes, from both of which catalytically active catechol 2,3-oxygenase activities were expressed. the kinetic parameters were determined for the gene products of both the hybrid and the wild-type xyle genes with catechol, 3-methylcatechol and 4-met ... | 1990 | 2262792 |
| growth-phase-dependent expression of the pseudomonas putida tol plasmid pww0 catabolic genes. | pseudomonas putida tol plasmid pww0 catabolic genes are clustered into two operons. the first, the upper operon, is controlled by the xylr regulatory gene, whereas the second, the meta operon, is controlled by the xyls regulatory gene. the xyls gene itself is subjected to control by xylr. in this study, we show that the tol catabolic operons were poorly induced in cells growing at the early-exponential-growth phase but strongly induced in cells at late-exponential-growth phase. we constructed fu ... | 1990 | 2254244 |
| purification and characterisation of tol plasmid-encoded benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase of pseudomonas putida. | benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase, two enzymes of the xylene degradative pathway encoded by the plasmid tol of a gram-negative bacterium pseudomonas putida, were purified and characterized. benzyl alcohol dehydrogenase catalyses the oxidation of benzyl alcohol to benzaldehyde with the concomitant reduction of nad+; the reaction is reversible. benzaldehyde dehydrogenase catalyses the oxidation of benzaldehyde to benzoic acid with the concomitant reduction of nad+; the re ... | 1990 | 2202600 |
| mutations leading to constitutive expression from the tol plasmid meta-cleavage pathway operon are located at the c-terminal end of the positive regulator protein xyls. | the xyls protein is the positive activator of the tol plasmid meta-cleavage pathway operon for the metabolism of alkylbenzoates in pseudomonas putida. the regulator stimulates transcription from the tol meta pathway operon promoter (pm) when activated by benzoate effectors or in the absence of effectors when overproduced. xyls mutant alleles that encode regulators which constitutively mediate expression from pm were isolated and characterized. the mutant proteins all exhibit single amino acid su ... | 1990 | 2193914 |
| a family of positive regulators related to the pseudomonas putida tol plasmid xyls and the escherichia coli arac activators. | the xyls family consists of a least 8 different transcriptional regulators. six of these proteins are positive regulators for the catabolism of carbon sources (benzoate and sugars) in escherichia coli, pseudomonas putida and erwinia carotovora, and two of them are involved in pathogenesis in escherichia coli and yersinia enterocolitica. based on protein alignments, the members of this family exhibit a long stretch of homology at the c-terminal end. the regulators involved in the catabolism of ca ... | 1990 | 2186376 |
| the meta cleavage operon of tol degradative plasmid pww0 comprises 13 genes. | the meta-cleavage operon of tol plasmid pww0 of pseudomonas putida encodes a set of enzymes which transform benzoate/toluates to krebs cycle intermediates via extradiol (meta-) cleavage of (methyl)catechol. the genetic organization of the operon was characterized by cloning of the meta-cleavage genes into an expression vector and identification of their products in escherichia coli maxicells. this analysis showed that the meta-cleavage operon contains 13 genes whose order and products (in kiloda ... | 1990 | 2183008 |
| upstream regulatory sequence for transcriptional activator xylr in the first operon of xylene metabolism on the tol plasmid. | transcription of the first operon coding for m-xylene-degrading enzymes on the tol plasmid of pseudomonas putida is activated by the xylr gene product in the presence of m-xylene. the operon has the consensus sequence of the ntr/nif promoters at -24 and -12 regions, and the transcription is dependent on an rna polymerase containing a sigma factor ntra (rpon or sigma 54). deletion derivatives of the upstream sequence of the operon promoter were made in vitro and connected with the xyle gene on a ... | 1990 | 2174974 |
| genetic analysis of chromosomal operons involved in degradation of aromatic hydrocarbons in pseudomonas putida tmb. | the catabolic pathway for the degradation of aromatic hydrocarbons encoded by pseudomonas putida tmb differs from the tol plasmid-encoded pathway as far as regulation of the upper pathway is concerned. we found, by analyzing tn5-induced mutants and by southern blot hybridization with appropriate probes derived from the tol plasmid pww0, that the catabolic genes of strain tmb were located on the bacterial chromosome and not on the 84-kb plasmid harbored by this strain. the catabolic genes of tmb ... | 1990 | 2172213 |
| loss of tdn catabolic genes by deletion from and curing of plasmid ptdn1 in pseudomonas putida: rate and mode of loss are substrate and ph dependent. | the ability to degrade aromatic amines and m-toluate (tdn+ phenotype), encoded by plasmid ptdn1, was lost from pseudomonas putida hosts after subculture in benzoate, succinate, acetate and glucose minimal medium, the fastest rate of loss occurring where benzoate was the substrate. tdn- cells had either lost the entire ptdn1 plasmid or suffered a recombinational deletion of a specific 26 kbp region. proportional increase of tdn- cells resulted from their growth-rate advantage, and additionally, w ... | 1990 | 2168928 |
| use of a novel cassette to label phenotypically a cryptic plasmid of bacillus subtilis and map loci involved in its stable maintenance. | in order to facilitate studies on the maintenance of cryptic plasmids from gram-positive bacteria we have constructed a novel cassette capg1000 (5.0 kb) which carries both a selectable marker (chloramphenicol resistance from staphylococcus aureus plasmid pc194) and a screenable marker (the xyle gene from the tol plasmid of pseudomonas putida expressed from a cloned promoter of bacillus phage spo2) and which is flanked by terminators to prevent transcription from the cassette activating or inhibi ... | 1990 | 2116498 |
| [comparative study of aromatic ring meta-cleavage enzymes in pseudomonas strains with plasmid and chromosomal genetic control of the catabolism of biphenyl and m-toluate]. | it was shown that two different enzymes of aromatic ring oxidative meta-cleavage (2,3-dihydroxybiphenyl-1,2-dioxygenase), dbo and catechol-2,3-dioxygenase, c230) function in pseudomonas strains with a plasmid and chromosomal genetic control of biphenyl and toluate catabolism. a comparative analysis of dbo's and c230's expressed by the pbs241 biphenyl degradative plasmid in p. putida bs893, pbs311 in p. putida u83, chromosomal genes in p. putida bf and c230 from p. putida paw160 (pwwo) was carrie ... | 1990 | 2096950 |