| micellar aggregation of 5 -3-keto steroids lacking a polar c-17 group and its relation to the activity and specificity of the 5 - 4 -3-ketosteroid isomerase of pseudomonas testosteroni. | | 1973 | 4683484 |
| molecular weight determination and structural studies of pseudomonas testosteroni delta 5 leads to 4-3-oxosteroid isomerase (ec 5.3.3.1). | | 1973 | 4753764 |
| [relation between enzyme induction and testosterone metabolism in pseudomonas testosteroni]. | | 1973 | 4803170 |
| specific activation of a tyrosine----glycine mutant of delta 5-3-ketosteroid isomerase by phenols. | a key unknown still to be explored concerning the mechanism of delta 5-3-ketosteroid isomerase from pseudomonas testosteroni is the extent of the proton transfer between tyrosine-14 of the enzyme and the c-3 carbonyl oxygen of the steroid substrate. this report is a preliminary study of a system we are developing to allow us eventually to use a brønsted analysis to measure this transfer. we describe the construction of an expression vector and tyrosine-14----glycine-14 mutant of the enzyme and i ... | 1992 | 1590799 |
| [inhibition of a dna-dependent rna biosynthesis by a macromolecular fraction of non-induced cells of pseudomonas testosteroni]. | | 1971 | 4939704 |
| inhibition of the 3-ketosteroid 5 - 4 -isomerase of pseudomonas testosteroni by some bromo-3-ketosteroid derivatives. | | 1972 | 5017704 |
| the amino acid sequence of 5 -3-ketosteroid isomerase of pseudomonas testosteroni. | | 1971 | 5135313 |
| enzymatic oxidation of steroids by cell-free extracts of pseudomonas testosteroni: isolation of cleavage products of ring a. | | 1965 | 5217462 |
| inhibition by 2'-deoxyadenosine of enzyme induction in pseudomonas testosteroni. | | 1965 | 5218718 |
| [relationship between the structure of a steroid and the inducing effect on 3 alpha-hydroxysteroid: nad oxidoreductase of pseudomonas testosteroni]. | | 1969 | 5345977 |
| homologies between enzymes involved in steroid and xenobiotic carbonyl reduction in vertebrates, invertebrates and procaryonts. | evidence is reported for the existence of a structurally and functionally related and probably evolutionarily conserved class of membrane-bound liver carbonyl reductases/hydroxysteroid dehydrogenases involved in steroid and xenobiotic carbonyl metabolism. carbonyl reduction was investigated in liver microsomes of 8 vertebrate species, as well as in insect larvae total homogenate and in purified 3 alpha-hydroxysteroid dehydrogenase preparations of the procaryont pseudomonas testosteroni, using th ... | 1992 | 1472459 |
| studies with the 3-alpha-hydroxysteroid dehydrogenase from pseudomonas testosteroni-enzyme-substrate complementarity as the basis of selectivity and steric specificity. | | 1967 | 5597320 |
| the metabolism of aromatic acids by pseudomonas testosteroni and p. acidovorans. | | 1967 | 5602468 |
| kinetics and stability of delta 5-3-ketosteroid isomerase from pseudomonas testosteroni in the system of reverse micelles of aerosol ot in isooctane. | partially purified delta 5-3-ketosteroid isomerase (ksi) from pseudomonas testosteroni was studied kinetically after solubilization in reverse micelles of aerosol ot (aot) in isooctane and water, as regards its application to biotechnology. with delta 5,10-estren-17 beta-ol-3-one as a substrate, ksi displays an enzyme activity in the micellar system but a low stability. in the presence of urea, the enzyme is, however, stable. kinetic parameters of the stabilized enzyme are highly sensitive to bo ... | 1992 | 1381618 |
| further studies of steoidal inhibitors of delpha5, 3beta-hydroxysteroid dehydrogenase and delta5-delta4, 3-ketosteroid isomerase in pseudomonas testosteroni and in bovine adrenals. | | 1968 | 5697036 |
| preparation of crystalline delta-5-3-ketosteroid isomerase from pseudomonas testosteroni. | | 1965 | 5849828 |
| inhibition of 3-beta-hydroxysteroid dehydrogenase from pseudomonas testosteroni by various estrogenic and progestinic steroids. | | 1967 | 6023578 |
| inhibition of the steroid-induced synthesis of delta-5-3-ketosteroid isomerase in pseudomonas testosteroni by a new purine deoxyribonucleoside analog: 6-chloro-8-aza-9-cyclopentylpurine. | | 1967 | 6033637 |
| [fatty acids of the cell wall and the membrane of pseudomonas testosteroni]. | | 1967 | 6053273 |
| identification of xenobiotic-degrading isolates from the beta subclass of the proteobacteria by a polyphasic approach including 16s rrna partial sequencing. | nineteen gram-negative, aerobic, biodegradative isolates were identified by using a polyphasic taxonomic approach. the presence of the specific polyamine 2-hydroxyputrescine and the presence of a ubiquinone with eight isoprenoid units in the side chain (ubiquinone q-8) allowed allocation of these organisms to the beta subclass of the proteobacteria. on the basis of the results of additional characterization experiments (i.e., api 20ne tests, determinations of soluble protein patterns, and dna-dn ... | 1992 | 1371062 |
| norethisterone and ethinylestradiol do not inhibit delta 5-3 beta-hydroxysteroid dehydrogenase in rat leydig cells. | the effect of norethisterone, norethisterone acetate, ethinylestradiol and of a cyanoketone on the activity of hsd have been studied. rat leydig cells and extracts of pseudomonas testosteroni were used as enzyme sources. conversion of [3h]dhea to a and [3h]pregnenolone to progesterone were used for the assay of enzyme activity. km values for each substrate for leydig cells and for bacterial enzyme were: 1.5 x 10(-5) mol l-1 and 6.0 x 10(-5) mol l-1 dhea; 1.3 x 10(-5) mol and 7.7 x 10(-5) mol l-1 ... | 1984 | 6237898 |
| new naphthalene-degrading marine pseudomonas strains. | over 100 strains that utilized naphthalene as the only carbon and energy source were isolated from samples of marine sediments taken from a heavily polluted area. the isolates were characterized taxonomically and physiologically. most of these strains belonged to the genus pseudomonas, and seven of them did not fit any previous taxonomic description. they differed from type strains in a few biochemical characteristics and in the utilization of aromatic compounds. none had catechol 1,2-dioxygenas ... | 1988 | 3202629 |
| proton nuclear magnetic resonance studies of pseudomonas testosteroni 3-oxo-delta 5-steroid isomerase and its interaction with 17 beta-estradiol. | | 1982 | 6295444 |
| nucleotide sequence of the gene for the delta 5-3-ketosteroid isomerase of pseudomonas testosteroni. | the structural gene for the delta 5-3-ketosteroid isomerase of pseudomonas testosteroni has been sequenced by the dideoxy method. the sequence obtained confirms the amino acid (aa) sequence of benson et al. [j. biol. chem. 246 (1971) 7514-7525] at all but 5 aa residues of the 125-aa polypeptide. amino acid residues 22, 24, 33, and 38, reported to be asparagines by benson et al., are found to be encoded by aspartic acid codons. amino acid residue 77, reported to be a glutamine by benson et al., i ... | 1988 | 3224818 |
| epr and mössbauer studies of protocatechuate 4,5-dioxygenase. characterization of a new fe2+ environment. | protocatechuate 4,5-dioxygenase from pseudomonas testosteroni has been purified to homogeneity and crystallized. the iron containing, extradiol dioxygenase is shown to be composed of two subunit types (alpha, mr = 17,700 and beta, mr = 33,800) in a 1:1 ratio; such a composition has not been observed for other extradiol dioxygenases. the 4.2 k mössbauer spectrum of native protocatechuate 4,5-dioxygenase prepared from cells grown in 57fe-enriched media consists of a doublet with quadrupole splitti ... | 1983 | 6317682 |
| [transformation of escherichia coli and different species of pseudomonas by a plasmid dna isolated from pseudomonas testosteroni]. | pseudomonas testosteroni uses testosterone as sole source of carbon. we were able to isolate an extrachromosomal dna from a strain of pseudomonas testosteroni and to obtain pseudomonas putida and aeruginosa and escherichia coli transformants catabolizing testosterone. | 1983 | 6416627 |
| cloning of the gene for delta 5-3-ketosteroid isomerase from pseudomonas testosteroni. | we have cloned an approx. 5-kb fragment of pseudomonas testosteroni dna containing the structural gene of delta 5-3-ketosteroid isomerase into the ecori site of the lambda gt11 genome. escherichia coli infected with these recombinant phages produce a polypeptide which is recognized by antiserum raised against the purified isomerase. four of the recombinant lambda gt11 clones contain significant levels of isomerase activity and produce an immunopositive polypeptide of the same apparent mr as the ... | 1987 | 3428616 |
| evaluation of the rapid nft system for identification of gram-negative, nonfermenting rods. | this study evaluated the ability of the rapid nft system (api system sa, montalieu-vercieu, france) to accurately identify 262 clinically isolated, gram-negative, nonfermentative rods without additional tests. identifications were classified as correct; low discrimination, with a spectrum of two or more possibilities (additional tests necessary for accurate identification); and incorrect. correct identification rates were analyzed in two categories: (i) correct to species or biotype for all orga ... | 1984 | 6490857 |
| isolation and sequencing of the gene encoding delta 5-3-ketosteroid isomerase of pseudomonas testosteroni: overexpression of the protein. | we describe the cloning, sequencing, and overexpression of the steroid isomerase (3-oxosteroid delta 5-delta 4-isomerase, ec 5.3.3.1) gene of pseudomonas testosteroni. a genomic library of p. testosteroni total dna constructed from partial ecori digests ligated to a lambda gtwes vector was probed with a 23-base oligonucleotide mixture [atgaac(t)acc(a,t)ccg(c,a)gag(a)cac(t)atgac] corresponding to the nh2-terminal sequence of steroid isomerase. subclones derived from a recombinant phage containing ... | 1987 | 3480517 |
| quinohaemoprotein alcohol dehydrogenase apoenzyme from pseudomonas testosteroni. | cell-free extracts of pseudomonas testosteroni, grown on alcohols, contain quinoprotein alcohol dehydrogenase apoenzyme, as was demonstrated by the detection of dye-linked alcohol dehydrogenase activity after the addition of pqq (pyrroloquinoline quinone). the apoenzyme was purified to homogeneity, and the holoenzyme was characterized. primary alcohols (except methanol), secondary alcohols and aldehydes were substrates, and a broad range of dyes functioned as artificial electron acceptor. optima ... | 1986 | 3521592 |
| nad(p)+-independent aldehyde dehydrogenase from pseudomonas testosteroni. a novel type of molybdenum-containing hydroxylase. | aldehyde dehydrogenase from pseudomonas testosteroni was purified to homogeneity. the enzyme has a ph optimum of 8.2, uses a wide range of aldehydes as substrates and cationic dyes (wurster's blue, phenazine methosulphate and thionine), but not anionic dyes (ferricyanide and 2.6-dichloroindophenol), nad(p)+ or o2, as electron acceptors. haem c and pyrroloquinoline quinone appeared to be absent but the common cofactors of molybdenum hydroxylases were present. xanthine was not a substrate and allo ... | 1987 | 3609027 |
| affinity alkylation of 3-oxo-delta 5-steroid isomerase by steroidal 3 beta-oxiranes: identification of the modified amino acid by reduction with hydroxyborohydride. | the steroidal 3 beta-oxirane (3s)-spiro[5 alpha-androstane-3,2'-oxiran]-17 beta-ol (1 beta) is an active site directed irreversible inhibitor of the 3-oxo-delta 5-steroid isomerase from pseudomonas testosteroni. two steroid-bound peptides (tps1 and tps2) were isolated by high-performance liquid chromatography (hplc) from the trypsin digest of enzyme inactivated with 1 beta. the modified tryptic peptides (residues 14-45 of the enzyme) were further digested with chymotrypsin, each giving rise to a ... | 1987 | 3620446 |
| the amino acid sequence of a delta 5-3-oxosteroid isomerase from pseudomonas putida biotype b. | we have determined the primary structure of a delta 5-3-oxosteroid isomerase from pseudomonas putida biotype b. the enzyme is a dimeric protein of two identical subunits, each consisting of a polypeptide chain of 131 residues and a mr = 14,536. the intact s-carboxymethyl protein was sequenced from the nh2 terminus using standard automated edman degradation and automated edman degradation using fluorescamine treatment at known prolines to suppress background. the isomerase was fragmented using cn ... | 1986 | 3700400 |
| pseudomonas testosteroni infections: eighteen recent cases and a review of the literature. | pseudomonas testosteroni has been largely overlooked as a potential pathogen in humans. ten cases of infection due to p. testosteroni were identified at a single metropolitan hospital in texas during a three-year period. the organism was most often found in association with anatomic abnormalities of the gastrointestinal tract (six of 10 cases); perforation of the appendix was the commonest abnormality (five cases). the infections were more often polymicrobial (seven cases) than monomicrobial (th ... | 1987 | 3823716 |
| irreversible inhibition of delta 5-3-oxosteroid isomerase by 2-substituted progesterones. | 2 alpha-cyanoprogesterone (i) and 2-hydroxymethyleneprogesterone (ii) were synthesized and screened as irreversible active-site-directed inhibitors of the delta 5-3-oxosteroid isomerase (ec 5.3.3.1) from pseudomonas testosteroni. both compounds were found to inhibit the purified bacterial enzyme in a time-dependent manner. in either case the inactivated enzyme could be dialysed without return of activity, indicating that a stable covalent bond had formed between the inhibitor and the enzyme. ina ... | 1985 | 3838891 |
| mitochondrial origins. | the 16s ribosomal rna sequences from agrobacterium tumefaciens and pseudomonas testosteroni have been determined to further delimit the origin of the endosymbiont that gave rise to the mitochondrion. these two prokaryotes represent the alpha and beta subdivisions, respectively, of the so-called purple bacteria. the endosymbiont that gave rise to the mitochondrion belonged to the alpha subdivision, a group that also contains the rhizobacteria, the agrobacteria, and the rickettsias--all prokaryote ... | 1985 | 3892535 |
| membrane-bound dehydrogenases of pseudomonas testosteroni. | | 1980 | 6931945 |
| mechanism of inactivation of 3-oxosteroid delta 5-isomerase by 17 beta-oxiranes. | the affinity label (17s)-spiro[estra-1,3,5(10),6,8-pentaene-17,2'-oxiran]-3-ol (5 beta) inactivates 3-oxosteroid delta 5-isomerase from pseudomonas testosteroni by formation of a covalent bond between asp-38 of the enzyme and the steroid. high-performance liquid chromatography (hplc) analysis of tryptic digests of inactivated enzyme shows that two isomeric steroid-containing peptides are formed in a ratio of 9:1 at ph 7 (tps1 and tps2). hydrolysis of each of these peptides produces a different s ... | 1985 | 4027215 |
| induction of 3-hydroxybenzoate 2-hydroxylase in a pseudomonas testosteroni mutant. | benzoate was established as the inducer of a unique 3-hydroxybenzoate 2-hydroxylase activity found in a pseudomonas testosteroni mutant which is unable to grow on m-hydroxybenzoate as its sole source of carbon and energy. | 1982 | 7054148 |
| testosterone-dependent oxygen consumption in membrane vesicles of pseudomonas testosteroni. | oxygen consumption was measured in membrane vesicles of pseudomonas testosteroni using conditions similar to those identified for testosterone transport in these vesicles. testosterone and nad+, which are primary requirements for testosterone transport, were both required for maximum oxygen consumption suggesting that testosterone transport and oxygen consumption were linked. testosterone-dependent oxygen consumption was inhibited by 95% by 1 mm kcn indicating that the electron-transport chain c ... | 1982 | 7109594 |
| extraction of a steroid transport system from pseudomonas testosteroni membranes and incorporation into synthetic liposomes. | a steroid binding protein has been extracted from pseudomonas testosteroni membranes with an organic solvent system. this protection binds some c19 and c21 steroids but not c18 steroids. when this protein is incorporated into synthetic lipid vesicles constructed from p. testosteroni phospholipids, the vesicles perform concentrative uptake of testosterone in the presence of the ionophore valinomycin. this steroid binding protein is thus believed to be the steroid permease of this organism. | 1985 | 4068713 |
| use of a solid-phase photoaffinity reagent to label a steroid binding site: application to the delta 5-3-ketosteroid isomerase of pseudomonas testosteroni. | in order to extend our analysis of the reactions that occur during the active site directed photoinactivation of delta 5-3-ketosteroid isomerase sensitized by unsaturated steroid ketone photoaffinity reagents, the site of covalent attachment has been identified. a solid-phase photoaffinity reagent, delta 6-testosterone-agarose, has been employed for this purpose; this type of reagent, in contrast to solution-phase reagents, facilitated the recovery of a peptide fragment of the isomerase bearing ... | 1985 | 4092021 |
| [determination of the characteristics of an inductor necessary for its interaction with a repressor in pseudomonas testosteroni]. | | 1972 | 4119671 |
| the degradation of l-histidine, imidazolyl-l-lactate and imidazolylpropionate by pseudomonas testosteroni. | 1. imidazol-5-ylpropionate and imidazol-5-yl-lactate are degraded by pseudomonas testosteroni via inducible pathways. 2. growth on either compound as the sole source of carbon results in the induction of the enzymes for histidine catabolism. 3. the pathway of histidine degradation in this organism, a non-fluorescent pseudomonad, is shown to be the same as that operating in pseudomonas fluorescens and pseudomonas putida. it consists of the successive formation of urocanate, imidazol-4-on-5-ylprop ... | 1973 | 4146796 |
| the control of the enzymes degrading histidine and related imidazolyl derivates in pseudomonas testosteroni. | 1. the induction of the enzymes for the degradation of l-histidine, imidazolylpropionate and imidazolyl-l-lactate in pseudomonas testosteroni was investigated. 2. the activities of histidine ammonia-lyase, histidine-2-oxoglutarate aminotransferase and urocanase are consistent with these enzymes being subject to co-ordinate control under most growth conditions. however, a further regulatory mechanism may be superimposed for histidase alone under conditions where degradation of histidine must take ... | 1973 | 4146797 |
| absolute configuration of a metabolite in the m-fission pathway of protocatechuate. | an aldolase, which is induced in pseudomonas testosteroni during growth with p-hydroxybenzoate, preferentially attacks the r form of 4-hydroxy-4-methyl-2-oxoglutarate, a metabolite of protocatechuate catabolism. | 1973 | 4347922 |
| proceedings: synthesis of rna and dna in isolated chromosome of pseudomonas testosteroni. | | 1974 | 4461578 |
| [studies on rna polymerase dna complex from pseudomonas testosteroni]. | | 1972 | 4649824 |
| influence of an 18-hydroxyl group on the interaction of oestrogens and hydroxysteroid oxidoreductases. | 1. partially purified 17beta-hydroxy steroid-nad(+) oxidoreductases, prepared from pseudomonas testosteroni (ec 1.1.1.51), human term placenta (ec 1.1.1.62) and the cytoplasmic fraction of rat liver (ec 1.1.1.-) were tested for their ability to catalyse the oxidoreduction of 18-hydroxyoestradiol-17beta and 18-hydroxyoestrone. the products of incubation were identified by chromatographic procedures and by mass spectrometry. 2. the pseudomonas enzyme catalysed both the oxidation of 18-hydroxyoestr ... | 1974 | 4824210 |
| the effect of carbonyl cyanide m-chlorophenylhydrazone on steroid transport in membrane vesicles of pseudomonas testosteroni. | the uncoupler carbonyl cyanide chlorophenylhydrazone (cccp) was an effective inhibitor of steroid transport in membrane vesicles of pseudomonas testosteroni between 10 microm and 1 microm cccp. at these concentrations the inhibition of steroid transport was not due to an inhibition of the 3 beta and 17 beta-hydroxysteroid dehydrogenase enzyme. cccp also affected testosterone-dependent oxygen consumption at concentrations up to 100 microm and inhibited respiration at 0.5 and 1 microm. the effect ... | 1983 | 6310264 |
| use of a simplified cell blot technique and 16s rrna-directed probes for identification of common environmental isolates. | a simple technique in which rrna-targeted oligodeoxynucleotide probes are used to identify bacteria immobilized on membranes is described. by using colony lifts, bacteria are directly transferred from plates to untreated nitrocellulose membranes. alternatively, cells resuspended from colonies can be applied to membranes by using a vacuum manifold under high-salt conditions. blotted cells are baked and hybridized under stringent conditions by using standard protocols. treatment of blotted cells w ... | 1993 | 7504429 |
| [isolation and study of a bacteriophage of pseudomonas testosteroni]. | a virulent phage specific for pseudomonas testosteroni is described. this phage have a regular icosahedral head (52 nm between opposite angles) and a contractile tail (165 x 8 nm) but no fibers on. the buoyant density is 1,51 +/- 0,01 g/ml. the nucleic acid is an desoxyribonucleic acid with a density of 1,696 +/- 0,03 g/ml and a gc% between 33,7 and 39,7. | 1980 | 6451268 |
| insights into the catalytic mechanism and active-site environment of comamonas testosteroni delta 5-3-ketosteroid isomerase as revealed by site-directed mutagenesis of the catalytic base aspartate-38. | delta 5-3-ketosteroid isomerase (ksi) of comamonas testosteroni catalyzes the isomerization of a wide variety of delta 5(6) and delta 5(10) steroids through the formation of an enzyme bound dienol(ate) intermediate. asp-38 has been strongly implicated in catalysis, apparently serving as a proton shuttle. in this paper the results of a detailed kinetic characterization of the ksi mutants d38e and d38h are presented. both mutants retain significant activity, with kcat and kcat/km values 10(3)-10(4 ... | 1995 | 7578024 |
| differences in inhibition by various steroids of rat testis and pseudomonas testosteroni delta 5-3 beta-hydroxysteroid dehydrogenase. | the influence of various estrogens, progestogens and of cyanoketone (2 alpha-cyano-4,4,17 alpha-trimethylandrost-5-en-17 beta-ol-3-one) on the enzyme activity of delta 5-3 beta-hydroxysteroid dehydrogenase (hsd) (ec 1.1.1.145) was studied. extracts of pseudomonas testosteroni, rat testis total homogenate and a microsomal preparation were used as enzyme sources. spectrophotometric determinations and the conversion of 3h-labelled dehydroepiandrosterone to androstenedione were used to assay for enz ... | 1983 | 6603965 |
| purification and characterization of a membrane-associated testosterone-binding protein from pseudomonas testosteroni. | a steroid-binding protein, identified in the supernatant generated when membrane vesicles of pseudomonas testosteroni are produced and harvested by centrifugation, has been purified 49-fold to homogeneity. it has a molecular weight of 30 000-35 000 and it specifically binds the c19 steroids dihydrotestosterone, testosterone, and androstenedione. it is a basic protein with an isoelectric point at ph 7.3. binding of testosterone exhibited normal saturation kinetics with an affinity constant, kd, o ... | 1983 | 6683990 |
| quinohaemoprotein ethanol dehydrogenase from comamonas testosteroni. purification, characterization, and reconstitution of the apoenzyme with pyrroloquinoline quinone analogues. | pyrroloquinoline-quinone(pqq)-free quinohaemoprotein ethanol dehydrogenase (qh-edh) apoenzyme was isolated from ethanol-grown comamonas testosteroni. the purified apoenzyme, showing a single band of 71 kda on native gel electrophoresis, could be only partially converted into active holoenzyme by addition of pqq in the presence of calcium ions. in addition to a band with a molecular mass of 71 kda, additional bands of 51 kda and 25 kda were observed with sds/page. analysis of the n-terminal seque ... | 1995 | 7601151 |
| characterization of the interaction between pqq and heme c in the quinohemoprotein ethanol dehydrogenase from comamonas testosteroni. | quinohemoprotein ethanol dehydrogenase from comamonas testosteroni (qh-edh) contains two cofactors, 2,7,9-tricarboxy-1h-pyrrolo[2,3-f]quinoline-4,5-dione (pqq) and heme c. since previous studies on the kinetics of this enzyme suggested that both participate in electron transfer, spectroscopic investigations were performed of the oxidized and reduced holo- and apoenzyme (without pqq but with heme c) to reveal the nature of the interaction between the two redox centers. from this it appears that t ... | 1995 | 7626615 |
| enzymatic function in crystals of delta 5-3-ketosteroid isomerase. catalytic activity and binding of competitive inhibitors. | crystals of the steroid-metabolizing enzyme, delta 5-3-ketosteroid isomerase (ec 5.3.3.1) from pseudomonas testosteroni, exhibit many enzymatic properties. each enzyme subunit in the lattice binds a competitive inhibitor, progesterone, with the same stoichiometry (1:1) and affinity (kd = 6 x 10(-6) m) as the enzyme in solution. another competitive inhibitor, 19-nortestosterone, competes with progesterone for the same binding sites in the crystal. the enzyme crystals catalyze the conversion of de ... | 1984 | 6746640 |
| aliphatic nitrilase from a soil-isolated comamonas testosteroni sp.: gene cloning and overexpression, purification and primary structure. | an aliphatic nitrilase, active on adiponitrile and cyanovaleric acid, was identified and purified from comamonas testosteroni sp. (ct). oligodeoxyribonucleotide probes were designed from limited amino acid (aa) sequence information and used to clone the corresponding gene, named nita. high homologies were found at the aa level between ct nitrilase and the sequences of known nitrilases. multi-alignment of sequenced nitrilases suggests that cys163 of ct plays an essential role in the active site. ... | 1995 | 7642130 |
| antibodies to pseudomonas testosteroni 3-oxosteroid delta 4-delta 5-isomerase. | | 1980 | 6774719 |
| the effect of 2,4-dinitrophenol on steroid transport in membrane vesicles of pseudomonas testosteroni. | steroid transport in pseudomonas testosteroni membrane vesicles was significantly inhibited by the uncoupled 2,4-dinitrophenol (dnp). inhibition of steroid transport was not due to inhibition of the 3 beta- and 17 beta-hydroxysteroid dehydrogenase by concentrations of up to 1 mm dnp. however, inhibition of this membrane-bound enzyme was measured at 10 mm dnp. the solubilized 3 beta- and 17 beta-hydroxysteroid dehydrogenase was more sensitive, being inhibited at both 1 and 10 mm dnp indicating a ... | 1983 | 6827840 |
| sequence of the bphd gene encoding 2-hydroxy-6-oxo-(phenyl/chlorophenyl)hexa-2,4-dienoic acid (hop/cpda) hydrolase involved in the biphenyl/polychlorinated biphenyl degradation pathway in comamonas testosteroni: evidence suggesting involvement of ser112 in catalytic activity. | the nucleotide sequence of bphd, encoding 2-hydroxy-6-oxo-(phenyl/chlorophenyl)hexa-2,4-dienoic acid hydrolase involved in the biphenyl/polychlorinated biphenyl degradation pathway of comamonas testosteroni strain b-356, was determined. comparison of the deduced amino-acid sequence with published sequences led to the identification of a 'lipase box', containing a consensus pentapeptide sequence glyxaaserxaagly. this suggested that the mechanism of action of this enzyme may involve an asp-ser-his ... | 1995 | 7737519 |
| photoaffinity modification of delta 5-3-ketosteroid isomerase by light-activatable steroid ketones covalently coupled to agarose beads. | in order to identify the minor site(s) of photoattachment of unsaturated steroid ketones to delta 5-3-ketosteroid isomerase from pseudomonas testosteroni, we have developed a solid-state photoaffinity labeling technique. two solid-state reagents, o-carboxymethylagarose-ethylenediamine-succinyl-17 beta-o-19-nortestosterone and o-carboxymethylagarose-ethylenediamine-succinyl-17 beta-o-4,6-androstadien-3-one, have been synthesized. under anaerobic conditions, isomerase bound to these resins is phot ... | 1983 | 6860646 |
| purification and properties of bile acid sulfate sulfatase from pseudomonas testosteroni. | the bile acid sulfate sulfatase (bss) produced by pseudomonas testosteroni was purified and characterized. chromatofocusing behavior and amino acid sequence over twelve amino acid residues from n-terminus of the enzyme indicated that bss was composed of two isoforms of which molecular weights were 125,000 and 103,000. each isoform was a homodimer of a subunit of which molecular weight was 53,000 or 51,000, respectively. the optimum ph was 8.5 and bss was stable at ph 5.8-8.0. the thermostability ... | 1994 | 7764976 |
| immunological relatedness of histidine ammonia-lyases from some species of pseudomonas: taxonomic implication. | 1. histidine ammonia-lyases (histidase ec 4.3.1.3) from pseudomonas testosteroni ncib 10808 and pseudomonas putida ncib 10807 were purified and specific antibody was raised to each separately in a rabbit. 2. immunological cross-reactions of each antibody to histidine ammonia-lyases from various species of pseudomonas were examined by the enzyme inhibition test. 3. the immunological data obtained suggest that these pseudomonas species can be classified into three groups. these cross-reactions ten ... | 1983 | 6862094 |
| partial purification and characterization of a membrane-associated steroid-binding protein from pseudomonas testosteroni. | a steroid-binding protein obtained from the supernatant of the final wash from the preparation of membrane vesicles was purified severalfold to near homogeneity. the protein binds c18 and c19 steroids but has the highest affinity for androstenedione (kd = 1.6 x 10(-10) m). the molecular weight is 51,000 - 58,000. binding activity is slightly inhibited by cu2+, ca2+, and mg2+ and completely inhibited by zn2+. the protein has no detectable steroid degradative activity. analysis of androstenedione ... | 1982 | 6889907 |
| membrane-associated steroid-binding proteins of pseudomonas testosteroni. | previous studies have established the presence of periplasmic steroid-binding proteins in induced pseudomonas testosteroni. this study reports the presence of two additional steroid-binding proteins which can be released from the cytoplasmic membrane during preparation of membrane vesicles. these two proteins differ from each other and from the periplasmic protein in some of their characteristics and steroid specificity, and appear to be distinct from the two membrane-bound steroid dehydrogenase ... | 1981 | 6949624 |
| bacterial metabolism of arylsulfonates. i. benzene sulfonate as growth substrate for pseudomonas testosteroni h-8. | pseudomonas testosteroni h-8 utilizes as sole carbon source benzene sulfonate (bs), p-toluene sulfonate (pts), and ethylbenzene sulfonate (ebs) but not higher homologs. growth on bs was rapid (generation time, 3 hr) and efficient (y = 57), and resulted in accumulation of sulfate. as the culture is acid-sensitive, the medium must be heavily buffered to permit extensive growth. the bs oxidase system is inducible. cells grown on bs, but not glutamate, oxidized bs, pts, or ebs without lag (qo(2) = 5 ... | 1971 | 5553286 |
| terephthalate 1,2-dioxygenase system from comamonas testosteroni t-2: purification and some properties of the oxygenase component. | comamonas testosteroni t-2, grown in terephthalate (ter)-salts medium, synthesizes inducible enzymes that convert ter to (1r,2s)-dihydroxy-3,5-cyclohexadiene-1,4-dicarboxylic acid (dcd) and protocatechuate (pc). anion-exchange chromatography of cell extracts yielded two sets of fractions, r and z, that were necessary for oxygenation of ter to dcd; we termed this activity the ter dioxygenase system (terdos). an nad(+)-dependent dcd dehydrogenase, which converted dcd to pc, overlapped all fraction ... | 1994 | 7961417 |
| description of the kinetic mechanism and the enantioselectivity of quinohaemoprotein ethanol dehydrogenase from comamonas testosteroni in the oxidation of alcohols and aldehydes. | initial rate studies were performed on the oxidation of (racemic) alcohols as well as aldehydes by quinohaemoprotein ethanol dehydrogenase, type 1, from comamonas testosteroni with potassium ferricyanide as electron acceptor. the data could be fitted with an equation derived for a mechanism (hexa-uni ping-pong) in which alcohols are oxidized to the corresponding carboxylic acids and the intermediate aldehyde becomes released from the enzyme. however, for some substrates it was necessary to assum ... | 1994 | 8001568 |
| the metabolism of protocatechuate by pseudomonas testosteroni. | 1. protocatechuate 4,5-oxygenase, purified 21-fold from extracts of pseudomonas testosteroni, was examined in the ultracentrifuge and assigned a mol.wt. of about 140000. 2. when diluted, the enzyme rapidly lost activity during catalysis. inactivation was partially prevented by l-cysteine. 3. with a saturating concentration of protocatechuate (1.36mm), k(m) for oxygen was 0.303mm. this value is greater than the concentration of oxygen in water saturated with air at 20 degrees . 4. cell extracts c ... | 1968 | 5683506 |
| regulation of chloro- and methylphenol degradation in comamonas testosteroni jh5. | comamonas testosteroni jh5 was isolated from a mixed bacterial culture enriched on different chloro- and methylphenols. the strain completely mineralized a mixture consisting of 4-chlorophenol (4-cp) and 4-methylphenol (4-mp). during degradation of the mixture, 4-hydroxybenzyl alcohol, 4-hydroxybenzaldehyde, 4-hydroxybenzoic acid, and 4-chlorocatechol were detected as short-lived intermediates. mineralization of 4-cp and that of 4-mp occurred successively and were accompanied by diauxic growth, ... | 1994 | 8074514 |
| kinetics and mechanism of heterogeneous hydrolysis of poly[(r)-3-hydroxybutyrate] film by pha depolymerases. | the kinetics and mechanism of enzymatic degradation on the surface of poly[(r)-3-hydroxybutyrate] (p[(r)-3hb]) film have been studied using three types of extracellular poly(hydroxyalkanoate) (pha) depolymerases from alcaligenes faecalis, pseudomonas picketti and comamonas testosteroni. the monomer and dimer of 3-hydroxybutyric acid were produced during the course of the enzymatic degradation of p[(r)-3hb] film, and the rate of production was determined by monitoring the increase in absorbance a ... | 1993 | 8110658 |
| extent of proton transfer in the transition states of the reaction catalyzed by the delta 5-3-ketosteroid isomerase of comamonas (pseudomonas) testosteroni: site-specific replacement of the active site base, aspartate 38, by the weaker base alanine-3-sulfinate. | previous studies of the mechanism of the steroid isomerase of comamonas (pseudomonas) testosteroni have identified aspartate 38 as the proton porter which transfers the substrate's 4 beta proton to the 6 beta position of the product. consequently, aspartate 38 functions as a base in the deprotonation of the substrate to form a dienol or dienolate intermediate, which then undergoes reprotonation from protonated aspartate 38 at c-6 beta to give the product. we have tried to characterize the transi ... | 1994 | 8117731 |
| mechanism of the reaction catalyzed by delta 5-3-ketosteroid isomerase of comamonas (pseudomonas) testosteroni: kinetic properties of a modified enzyme in which tyrosine 14 is replaced by 3-fluorotyrosine. | tyrosine 14 of delta 5-3-ketosteroid isomerase plays an important role in the function of the enzyme, since its replacement by phenylalanine results in a decrease in kcat by a factor of 10(-4.7). this result and the fact that this residue resides in the enzyme's substrate binding site and is in close proximity to c-2 of the bound steroid suggests that it functions as an electrophile in the catalytic mechanism by protonation of or hydrogen bonding to the c-3 carbonyl oxygen of the substrate. in o ... | 1994 | 8117732 |
| factors affecting pcb degradation by an implanted bacterial strain in soil microcosms. | pseudomonas testosteroni b-356 was able to degrade approximately 50% of the aroclor 1242 mixture in shaken culture. the aims of the present study were to evaluate the capabilities of this bacterial strain to degrade pcbs in soil microcosms and to identify some of the factors likely to favor the degradative performance of the implanted bacteria. the presence of biphenyl as cosubstrate was the most important factor affecting pcb degradation in soil. however, because biphenyl was rapidly depleted i ... | 1993 | 8358671 |
| protection of substrate against enzymatic action by binding to proteins. dependence upon enzyme and binding protein. | in fetal or adult rats estradiol is carried in the plasma by alpha-fetoprotein or albumin. the protection of the carriers toward enzymatic oxidation by 17 beta-hydroxysteroid dehydrogenase from rat liver has been studied. concentrations of carrier protein and estradiol were adjusted to give free estradiol concentrations varying from km/10 to km/100 and the ratio of the catalytic velocity to that observed for the same concentration of free estradiol in the absence of carrier protein were recorded ... | 1980 | 6156164 |
| telluria mixta (pseudomonas mixta bowman, sly, and hayward 1988) gen. nov., comb. nov., and telluria chitinolytica sp. nov., soil-dwelling organisms which actively degrade polysaccharides. | pseudomonas mixta (type strain, acm 1762 [= atcc 49108], an actively dextranolytic species that possesses both lateral and polar flagella, was compared with the strictly aerobic, rod-shaped, chitinolytic bacterium "pseudomonas chitinolytica" acm 3522t (= cncm i-804) (t = type strain), which has a similar flagellation pattern, by performing phenotypic characterization and dna-dna hybridization studies and by analyzing dna base compositions and 16s rrna sequences. our results indicated that "p. ch ... | 1993 | 8427803 |
| influence of the position of the double bond in steroid substrates on the efficiency of the proton-transfer reaction by pseudomonas testosteroni 3-oxo-steroid delta 4-delta 5-isomerase. | studies of the proton-transfer reaction by pseudomonas testosteroni 3-oxo steroid delta(4)-delta(5)-isomerase with delta(5(6))- and delta(5(10))-steroid substrates demonstrate the importance of the position of the double bond for the efficiency of the isomerization process. thus 3-oxo-delta(5(6))-substrates have markedly high k(cat.) values, whereas those of 3-oxo-delta(5(10))-substrates are very low and their apparent k(m) values approach equilibrium dissociation constants. the first step in th ... | 1980 | 6248031 |
| quinoline 2-oxidoreductase and 2-oxo-1,2-dihydroquinoline 5,6-dioxygenase from comamonas testosteroni 63. the first two enzymes in quinoline and 3-methylquinoline degradation. | the enzymes catalysing the first two steps of quinoline and 3-methylquinoline degradation by comamonas testosteroni 63 were investigated. quinoline 2-oxidoreductase, which catalyses the hydroxylation of (3-methyl-)quinoline to (3-methyl-)2-oxo-1,2-dihydroquinoline, was purified to apparent homogeneity. the native enzyme, with a molecular mass of 360 kda, is composed of three non-identical subunits (87, 32, and 22 kda), occurring in a ratio of 1.16:1:0.83. containing fad, molybdenum, iron, and ac ... | 1995 | 7556204 |
| microbial metabolism of quinoline and related compounds. xvii. degradation of 3-methylquinoline by comamonas testosteroni 63. | a bacterial strain which utilizes 3-methylquinoline as sole source of carbon, nitrogen and energy was isolated from activated sludge. on the basis of its morphological and physiological characteristics, this isolate was classified as comamonas testosteroni. four metabolites of 3-methylquinoline degradation were isolated from the culture supernatant and identified as 3-methyl-2-oxo-1,2-dihydroquinoline, 6-hydroxy-3-methyl-2-oxo-1,2-dihydroquinoline, 5,6-dihydroxy-3-methyl-2-oxo-1,2-dihydroquinoli ... | 1993 | 8489738 |
| carbonyl reduction by 3 alpha-hsd from comamonas testosteroni--new properties and its relationship to the scad family. | | 1993 | 8493916 |
| molecular analysis of isophthalate and terephthalate degradation by comamonas testosteroni yzw-d. | comamonas testosteroni yzw-d was isolated from passaic river sediment for its ability to degrade isophthalate and terephthalate. degradation of the two isomeric compounds proceeds via separately inducible catabolic pathways that converge at protocatechuate. analysis of the catabolic pathways by which these two isomers are degraded demonstrated that a cis-dihydrodiol intermediate is involved in both pathways. the genes for the conversion of isophthalate and terephthalate to protocatechuate were c ... | 1995 | 8565920 |
| molecular cloning of novel genes for polycyclic aromatic hydrocarbon degradation from comamonas testosteroni gz39. | three strains of comamonas testosteroni were isolated from river sediment for the ability to degrade phenanthrene; two of the strains also grew on naphthalene, and one strain also grew on anthracene. the homology of the genes for polycyclic aromatic hydrocarbon degradation in these strains to the classical genes (nah) for naphthalene degradation from pseudomonas putida ncib 9816-4 was determined. the three c. testosteroni strains showed no homology to the nah gene probe even under low-stringency ... | 1996 | 8572701 |
| biodegradation of polychlorinated biphenyls by rhizobia: a novel finding. | metabolism of simple aromatic compounds in rhizobial strains has been a subject of study for a few decades, due either to the significance of nutritional diversity in the inoculum survival during agricultural applications or to the importance of plant phenolics in the microbe-plant cross-talk and signal-transduction. here, we report the capability of rhizobial strains to catabolize polychlorinated biphenyls (pcbs). in order to identify the genes in these strains that mediate the catabolism of pc ... | 1996 | 8579613 |
| purification and characterization of the comamonas testosteroni b-356 biphenyl dioxygenase components. | in this report, we describe some of the characteristics of the comamonas testosteroni b-356 biphenyl (bph)-chlorobiphenyl dioxygenase system, which includes the terminal oxygenase, an iron-sulfur protein (ispbph) made up of an alpha subunit (51 kda) and a beta subunit (22 kda) encoded by bpha and bphe, respectively; a ferredoxin (ferbph; 12 kda) encoded by bphf; and a ferredoxin reductase (redbph; 43 kda) encoded by bphg. ispbph subunits were purified from b-356 cells grown on bph. since highly ... | 1995 | 7592440 |
| crystallization and crystal packing of recombinant 3 (or 17) beta-hydroxysteroid dehydrogenase from comamonas testosteroni attc 11996. | the enzyme 3 (or 17) beta-hydroxysteroid dehydrogenase from comamonas testosteroni was crystallized. crystals, of up to 0.6 mm in their longest dimension and suitable for a crystallographic analysis have been obtained by the vapour diffusion method. they belong to the orthorhombic lattice type and diffract to a maximum resolution of 0.23 nm. a final data set obtained by merging data from three crystals resulted in a completeness of 90% with an rmerge of 6%. a molecular replacement search carried ... | 1996 | 8617258 |
| characterization of active recombinant his-tagged oxygenase component of comamonas testosteroni b-356 biphenyl dioxygenase. | biphenyl (bph) dioxygenase oxidizes bph to 2,3-dihydro-2,3-dihydroxybiphenyl in comamonas testosteroni b-356. the enzyme comprises a two-subunit iron-sulfur protein (ispbph), a ferredoxin ferbph, and a ferredoxin reductase redbph. redbph and ferbph transfer electrons from nadh to an fe-s active center of ispbph which activates molecular oxygen for insertion into the substrate. in this work b-356 ispbph complex and its alpha and beta subunits were purified from recombinant escherichia coli strain ... | 1996 | 8626504 |
| chemical structure of lipid a isolated from comamonas testosteroni lipopolysaccharide. | the chemical structure of lipid a of lipopolysaccharide isolated from comamonas testosteroni was determined by quantitative analysis, methylation analysis, mass spectrometry and nmr spectroscopy. the lipid a backbone was found to consist of 6-o-(2-deoxy-2-amino-beta-d-glucopyranosyl)-2-deoxy-2-amino-alpha-d-g luc ose which was phosphorylated in positions 1 and 4'. hydroxyl groups at positions 4 and 6' were unsubstituted, and position 6' of the non-reducing terminal residue was identified as the ... | 1996 | 8647087 |
| characterization of the gene encoding quinohaemoprotein ethanol dehydrogenase of comamonas testosteroni. | the gene encoding quinohaemoprotein ethanol dehydrogenase type i (qh-edhi) from comamonas testosteroni has been cloned and sequenced. comparison of the amino acid sequence deduced from this with that determined for the n-terminal amino acid stretch of purified qh-edhi, suggests that the gene also contains a leader sequence of 31 residues. based on this information, the molecular mass of the apo-enzyme, i.e. the enzyme without the cofactors pyrroloquinoline quinone (pqq) and haem c, and without t ... | 1996 | 8654419 |
| molecular cloning, expression in streptomyces lividans, and analysis of a gene cluster from arthrobacter simplex encoding 3-ketosteroid-delta 1-dehydrogenase, 3-ketosteroid-delta 5-isomerase and a hypothetical regulatory protein. | the arthrobacter simplex gene coding for 3-ketosteroid-delta 1-dehydrogenase, a key enzyme in the degradation of the steroid nucleus, was cloned in streptomyces lividans. nucleotide sequence analysis revealed that the gene for 3-ketosteroid-delta 1-dehydrogenase (ksdd) is clustered with at least two more genes possibly involved in steroid metabolism. upstream of ksdd, we found a gene, ksdr, encoding a hypothetical regulatory protein that shows homologies to kdgr, the negative regulator of pectin ... | 1995 | 7596291 |
| characterization by arbitrary primer polymerase chain reaction of polychlorinated biphenyl (pcb)-degrading strains of comamonas testosteroni isolated from pcb-contaminated soil. | in this study, we isolated and characterized biphenyl (bp) and polychlorinated biphenyl (pcb) degrading bacterial strains found in pcb-contaminated soil from an auto manufacturing plant located in syracuse, new york. twenty-one bp and pcb-degrading bacteria were randomly selected to form a representative sample of the bacterial population present at the site. of the 21 bacteria, 13 were identified as comamonas testosteroni, constituting about 60% of the bacterial population examined. other pcb d ... | 1995 | 7641143 |
| comamonas testosteroni colony phenotype influences exopolysaccharide production and coaggregation with yeast cells. | a comamonas testosteroni strain was isolated from activated sludge on the basis of its ability to coaggregate with yeast cells. on agar plates the following two types of colonies were formed: colonies with a mucoid appearance and colonies with a nonmucoid appearance. on plates this strain alternated between the two forms, making sectored colonies. in liquid medium with constant agitation no such change was observed. in the absence of agitation and in contact with a glass surface a culture with p ... | 1996 | 8702260 |
| characterization of active recombinant 2,3-dihydro-2,3-dihydroxybiphenyl dehydrogenase from comamonas testosteroni b-356 and sequence of the encoding gene (bphb). | 2,3-dihydro-2,3-dihydroxybiphenyl-2,3-dehydrogenase (b2,3d) catalyzes the second step in the biphenyl degradation pathway. the nucleotide sequence of comamonas testosteroni b-356 bphb, which encodes b2,3d, was determined. structural analysis showed that the dehydrogenases involved in the bacterial degradation of aromatic compounds are related to each other and that their phylogenetic relationships are very similar to the relationships observed for dioxygenases that catalyze the initial reaction ... | 1996 | 8702262 |
| antibiotic resistance and enhanced insecticide catabolism as consequences of steroid induction in the gram-negative bacterium comamonas testosteroni. | the effects of steroid induction on antibiotic resistance against the fungal steroid fusidic acid (ramycin; 16-(acetyloxy)-3 alpha,11 alpha-dihydroxy-29-dammara-17(20), 24-dien-21-oic-acid) as well as on carbonyl reduction and degradation of the novel anti-insect agent nki 42255 (2-(1-imidazolyl)-1-(4-methoxyphenyl)-2-methyl-1-propanone) were studied in the gram-negative soil bacterium comamonas testosteroni strain atcc 11996. cells grown with testosterone as inducing agent showed a 5-6-fold ele ... | 1996 | 8809204 |
| degradative pathways for p-toluenecarboxylate and p-toluenesulfonate and their multicomponent oxygenases in comamonas testosteroni strains psb-4 and t-2. | three multicomponent oxygenases involved in the degradation of p-toluenesulfonate and p-toluenecarboxylate and the regulation of their synthesis have been examined in three strains (t-2, psb-4 and ter-1) of comamonas testosteroni. strain t-2 utilizes p-toluenesulfonate as a source of carbon and energy for growth via p-sulfobenzoate and protocatechuate, and p-toluenecarboxylate via terephthalate and protocatechuate, and has the unusual property of requiring the reductase (tsab) of the toluenesulf ... | 1996 | 8828208 |
| sequencing of comamonas testosteroni strain b-356-biphenyl/chlorobiphenyl dioxygenase genes: evolutionary relationships among gram-negative bacterial biphenyl dioxygenases. | in a previous work, all three components of comamonas testosteroni b-356 biphenyl (bph)/chlorobiphenyls (pcbs) dioxygenase (dox) have been purified and characterized. they include an iron-sulphur protein (ispbph) which is the terminal oxygenase composed of two subunits (encoded by bpha and bphe), a ferredoxin (ferbph) encoded by bphf and a reductase (redbph) encoded by bphg. bphg is not located in the neighbourhood of bphaef in b-356. we are reporting the cloning of b-356-bphg and the sequencing ... | 1996 | 8890734 |
| characterization of a 3 alpha-hydroxysteroid dehydrogenase/carbonyl reductase from the gram-negative bacterium comamonas testosteroni. | a new form of the nad(p)-dependent 3 alpha-hydroxysteroid dehydrogenases (3 alpha-hsds), present in the gram-negative bacterium comamonas testosteroni atcc 11996, was isolated from a testosterone-induced bacterial extract and characterized. the enzyme (hsd 28) has a monomeric molecular mass of 28 kda. it belongs to the protein superfamily of short-chain dehydrogenases/reductases (sdr) as established by n-terminal sequence analysis. along with the 3 alpha-hydroxysteroid dehydrogenase and 3-oxo-re ... | 1996 | 8944761 |
| rp4::mu3a-mediated in vivo cloning and transfer of a chlorobiphenyl catabolic pathway. | chromosomal dna fragments encoding the ability to utilize biphenyl as sole carbon source (bph+) were mobilized by means of plasmid rp4::mu3a from strain jb1 (tentatively identified as burkholderia sp.) to alcaligenes eutrophus ch34 at a frequency of 10(-3) per transferred plasmid. the mobilized dna integrated into the recipient chromosome or was recovered as catabolic prime plasmids. three bph+ prime plasmids were transferred from a. eutrophus to escherichia coli and back to a. eutrophus without ... | 1996 | 8969525 |
| ultraviolet resonance raman spectroscopy of delta 5-3-ketosteroid isomerase revisited: substrate polarization by active-site residues. | the delta 5-3-ketosteroid isomerase (ec 5.3.3.1) of pseudomonas testosteroni promotes extremely rapid conversion of delta 5- to delta 4-3-ketosteroids by a conservative intramolecular proton transfer via an enolic intermediate. the competitive inhibitor 19-nortestosterone displays marked spectroscopic changes upon binding to the enzyme, but the mechanisms responsible for these changes have not been unequivocally established. ultraviolet resonance raman (uvrr) spectra are reported for 19-nortesto ... | 1995 | 7703258 |