Publications

bacterial cytochromes. i. cytochrome composition of micrococcus denitrificans and pseudomonas denitrificans.		1956	13367070
the influence of oxygen on the reduction on nitrate by adapted cells of pseudomonas denitrificans.		1957	13413731
the influence of oxygen availability on the degree of nitrate reduction by pseudomonas denitrificans.		1957	13437212
production and utilization of nitrous oxide by pseudomonas denitrificans.		1959	13620649
taxonomic relationships among the pseudomonads.	colwell, r. r. (university of washington, seattle), and j. liston. taxonomic relationships among the pseudomonads. j. bacteriol. 82:1-14. 1961.-an electronic computer technique, utilizing the adansonian principle that every feature should have equal weight, was applied in an effort to derive a taxonomy of the pseudomonas-achromobacter group of gram-negative, asporogenous, rodlike bacteria. the validity of the general method was tested by an analysis of 40 well defined strains, principally derive ...	1961	13694873
[studies on the carbon metabolism of pseudomonas fluorescens and pseudomonas denitrificans].		1962	14459123
oxidative phosphorylation coupled with nitrate respiration with cell free extract of pseudomonas denitrificans.		1963	13939676
effect of hemin and oxygen tension on growth and nitrate reduction by bacteria.	jacobs, n. j. (american meat institute foundation, chicago, ill.), r. e. heady, j. m. jacobs, k. chan, and r. h. deibel. effect of hemin and oxygen tension on growth and nitrate reduction by bacteria. j. bacteriol. 87:1406-1411. 1964.-the effect of hemin supplementation of growth media on the ability of several bacteria to reduce nitrate was studied. added hemin had no detectable effect on the ability of these organisms to reduce nitrate when grown in stationary cultures exposed to air. however, ...	1964	14188721
phosphorylation associated with nitrate and nitrite reduction in micrococcus denitrificans and pseudomonas denitrificans.		1966	4288129
inhibition of growth of pseudomonas denitrificans by amino acids.		1966	5963324
some properties of a nitrite reductase from pseudomonas denitrificans.		1968	4384978
azurin: x-ray data for crystals from pseudomonas denitrificans.		1968	5729678
alternate requirement for vitamin b12 or methionine in mutants of pseudomonas denitrificans, a vitamin b12-producing bacterium.	experiments are described which indicate that pseudomonas denitrificans, an organism that overproduces vitamin b(12), uses the b(12) pathway exclusively for methionine synthesis.	1969	5802615
crystallization of cytochrome c-553 in aerobically grown pseudomonas denitrificans.		1969	5366991
uptake of pimelic acid by escherichia coli and pseudomonas denitrificans.		1969	4894285
azurin: x-ray data for crystals from pseudomonas denitrificans.	azurin, a blue-colored copper protein, from a soil bacteria, pseudomonas denitrificans, has been crystallized and its molecular weight of 16,000 was confirmed by means of x-ray difraction.	1969	17840685
pseudomonas denitrificans cytochrome cc'.		1970	4925005
some factors influencing vitamin b 12 production by pseudomonas denitrificans.		1970	5506085
some properties of a nitrate reductase from pseudomonas denitrificans.		1970	4316095
characterization of the late steps of microbial heme synthesis: conversion of coproporphyrinogen to protoporphyrin.	cell-free extracts of various cytochrome-containing, heterotrophic microorganisms were examined for ability to convert coproporphyrinogen to protoporphyrin. extracts of escherichia coli and pseudomonas denitrificans readily accumulated large amounts of protoporphyrin when assayed under aerobic conditions. however, protoporphyrin did not accumulate under either aerobic or anaerobic conditions of assay or in the presence of various supplements in extracts of the aerobe micrococcus lysodeikticus, t ...	1971	4935319
porphyrin overproduction by pseudomonas denitrificans: essentiality of betaine and stimulation by ethionine.	ethionine supplementation of a defined medium for growth of pseudomonas denitrificans inhibited vitamin b(12) overproduction and led to the elaboration of a red pigment. the pigment was shown to be coproporphyrin iii. inhibition by ethionine of cobalamin synthesis is probably due to interference of methylation of the corrin nucleus by methionine. accumulation of coproporphyrin iii is thought to result from interference by ethionine with the activity of methionine in the coproporphyrinogenase rea ...	1971	5113597
[study of intermediate stages of biochemical oxidation of higher n-alkanes by means of paraffin-negative mutants of pseudomonas denitrificans].		1972	5042093
degradation of naphthalene to salicylic acid by cultures of pseudomonas denitrificans and achromobacter sp. from the effluents of petroleum refinery.		1972	5061369
betaine-homocysteine transmethylase in pseudomonas denitrificans, a vitamin b 12 overproducer.	a pantothenate-methionine auxotroph (j741) of pseudomonas denitrificans was isolated whose growth requirement for methionine could not be satisfied by known precursors of the amino acid, including homocysteine. however, some "methyl rich" compounds such as betaine and dimethylacetothetin (dmt) could satisfy the requirement. s-methyl-methionine and s-adenosylmethionine were ineffective. extracts were found to contain an enzyme, betaine-homocysteine transmethylase (bhtase), that uses betaine or dm ...	1973	4688138
adenylate kinase from pseudomonas denitrificans. i. purification and antiserum inhibition.		1974	4369758
the partial characterization of purified nitrite reductase and hydroxylamine oxidase from nitrosomonas europaea.	nitrite reductase has been separated from cell-free extracts of nitrosomonas and partially purified from hydroxylamine oxidase by polyacrylamide-gel electrophoresis. in its oxidized state the enzyme, which did not contain haem, had an extinction maximum at 590nm, which was abolished on reduction. sodium diethyldithiocarbamate was a potent inhibitor of nitrite reductase. enzyme activity was stimulated 2.5-fold when remixed with hydroxylamine oxidase, but was unaffected by mammalian cytochrome c. ...	1974	4154745
effects of a nitrate reductase inactivating enzyme and nad(p)h on the nitrate reductase from higher plants and neurospora.	evidence is presented which suggests that the nad(p)h-cytochrome c reductase component of nitrate reductase is the main site of action of the inactivating enzyme. when tested on the nitrate reductase (nadh) from the maize root and scutella, the nadh-cytochrome c reductase was inactivated at a greater rate than was the fadh2-nitrate reductase component. with the neurospora nitrate reductase (nadph) only the nadph-cytochrome c reductase was inactivated. p-chloromercuribenzoate at 50 mum, which gav ...	1975	235300
[quantitative analysis of polypeptides by disc electrophoresis in pore gradients].	the quantitation of components in a complex mixture of proteins of pseudomonas denitrificans separated by disc-electrophoresis in the linear pore gradient of polyacrylamide gel was studied. the problem of a poor staining of proteins in the presence of a detergent was solved by a high resolving power photography. a linear correlation between the amount of protein in the fraction and the intensity of amide black staining was extablished. in comparison to the wild type of p. denitrificans the aldeh ...	1975	1129223
growth yield of a denitrifying bacterium, pseudomonas denitrificans, under aerobic and denitrifying conditions.	the effciency of denitrification, or anaerobic respiration, in pseudomonas denitrificans was investigated, using growth yield as an index. glutamate was mainly used as the sole source of energy and carbon. in batch culture, the growth yield per mole of electrons transported through the respiratory system under denitrifying conditions was about half that under aerobic conditions. similar figures were also obtained in chemostat cultures under glutamate-limited conditions. the decrease in growth yi ...	1975	1151326
energy yield of denitrification: an estimate from growth yield in continuous cultures of pseudomonas denitrificans under nitrate-, nitrite- and oxide-limited conditions.	the molar growth yields of pseudomonas denitrificans, for nitrate, nitrite and nitrous oxide, were determined in chemostat culture under electron acceptor-limited conditions. glutamate was used as the source of energy, carbon and nitrogen. the catabolic pattern was identical, irrespective of the terminal electron acceptors. the molar growth yields, corrected for maintenance energy, were 28-6 g/mol nitrate, 16-9 g/mol nitrite and 8-8 g/mol nitrous oxide. the energy yield, expressed on an electron ...	1975	1151328
[positive mutation as regards n-alkane oxidation in pseudomonas denitrificans].	differences in the overall protein composition were studied in the wild-type and mutant cells of pseudomonas denitrificans. pleiotropic mutation was established, which was characterized by quantitative and qualitative changes in at least 6 to 8 protein fractions and corresponded to the appearance of 2 to 3 steps of oxidation of higher n-alkanes, as had been found earlier in biochemical experiments. new enzymatic functions may appear on the basis of genetically determined proteins available, upon ...	1975	1160649
[effect of the growth phase and nutrient medium on the survival of lyophilized cells of pseudomonas denitrificans].	the influence of the growth phase and cultivation condition of pseudomonas denitrificans on the survival of the culture after lyophilization was examined. the culture removed for drying in the stationary phase showed the highest resistance to lyophilization. the cells dried at the beginning of exponential phase displayed enhanced sensitivity to lyophilization. addition to the cultivation medium (meat-peptone broth) of tween-80 (0.25%) caused an increase of proteins, lipids and polysaccharides in ...	1975	1208409
[the relation of membrane proteins to primary oxidation of higher ri-alkanes by pseudomonas denitrificans].	protein composition of enriched with cell walls membrane preparations from two ps. denitrificans mutants is comparatively studied. mutants have a genetic blocking of first steps of higher n-alkanes oxidation. differences in three protein components are found using disc electrophoresis in a system containing sodium dodecylsulphate. this is supposed to be an evidence of possible relation of changed mutant proteins to enzymatic alkanes oxidation.	1975	1212460
[membrane proteins of the hydrocarbon oxidation system in pseudomonas denitirficans].	pseudomonas denitrificans membranes have been isolated. difference of membranes in peculiar protein fractions on the account of mutation in the oxidation system of higher n-alkanes is revealed. reorganization of membrane connected with the change of protein showing the property of structural protein and taking part in alkane oxidation is observed. participation of structural protein in providing substrate specificity of oxidation complex is supposed.	1976	1053040
[chemcial aspects of the energy process in nitrate reduction in different representatives of soil microflora].	chemical aspects of dissimilatory nitrate reduction were studied by mass spectrometry in the following soil bacteria: bacillus filaris, bacillus polymyxa and pseudomonas denitrificans. chemical peculiarity of this process in spore-forming soil bacteria is the simultaneous operation of two energy processes: denitrification and nitrate respiration. the first process is terminated by the formation of molecular nitrogen, the second, by the production of ammonia. the quantitative ratio between these ...	1977	600102
numerically dominant denitrifying bacteria from world soils.	nineteen soils, three freshwater lake sediments, and oxidized poultry manure were examined to determine the dominant denitrifier populations. the samples, most shown or expected to support active denitrification, were from eight countries and included rice paddy, temperate agricultural, rain forest, organic, and waste-treated soils. over 1,500 organisms that could grow anaerobically on nitrate agar were isolated. after purification, 146 denitrifiers were obtained, as verified by production of n( ...	1977	869539
[relation of proteolytic activity to the ability to assimilate higher n-alkanes in pseudomonas denitrificans].	a correlation between proteolytic activity and the ability to assimilate higher n-alkanes was found while studying proteolysis of gelatin by 284 paraffin-negative mutants of pseudomonas denitrificans. the mutants were produced by a paraffin-positive strain capable of gelatin proteolytis, but not growing on glucose. if assimilation of the oxidized derivatives of higher n-alkanes, viz. alcohols and aldehydes, is interfered with at a genetical level, the percentage of mutants possessing extracellul ...	1977	909463
[specific gravity of the dried biomass of pure bacterial cultures].	the weight of wet and dry biomass taken from colonies after growth on mpa was determined in pure bacterial cultures of pseudomonas denitrificans and brevibacterium imperiale, and the number and dimensions of bacterial cells in dry preparations of the same colonies were measured by means of membrane filters. the average specific weight of dry biomass was found to be 1.68 and 1.62. in calculating the weight of bacterial biomass in pure cultures and natural cenoses, its volume should be assayed tak ...	1978	661634
[2,4,6-trinitrotoluene as a nutritional source for bacteria].	2,4,6-trinitrotoluene (tnt) is one of the most stable toxic substances belonging to nitroaryls which is introduced into water reservoirs with industrial wastes. its metabolism by microorganisms was studied in this work. the nitrogen of tnt is less accessible for pseudomonas denitrificans than for escherichia coli. in the latter case, tnt can be compared with ammonium sulphate. as a source of carbon, tnt is not utilized at all by e. coli and is hardly accessible for ps. denitrificans. the data ob ...	1978	353447
[electrophoretic differences in the proteins of the species pseudomonas aeruginosa and pseudomonas denitrificans capable of oxidizing n-alkanes].	pseudomonas aeruginosa and ps. denitrificans are capable of growing on n-alkanes, but differ in assimilation of higher and lower alkanes. the proteins of their cell-free homogenates were analysed by disc-electrophoresis in a system containing sds. the "preliminarily adapted" strain of ps. aeruginosa did not differ from the "non-adapted" to n-hexane strain, though both differed considerably from ps. denitrificans in the composition of protein spectrum. therefore, disc-electrophoresis of total pro ...	1978	106218
isolation and properties of cytochrome c peroxidase from pseudomonas denitrificans.	the isolation of cytochrome c peroxidase, cytochrome c4, cytochrome c-551 and azurin from pseudomonas dentrificans is described. the peroxidase has a molecular weight of 63,000 and an isoelectric point of 5.6. its absorption spectrum suggests that it contains two haem c groups/molecule. preliminary steady-state kinetic data are reported with cytochromes c-551 and c4 and azurin as the second substrate.	1979	226080
nitrite reduction with formate in pseudomonas denitrificans atcc 13867.		1979	454392
[nitrogen transformation as a result of pseudomonas denitrificans denitrification].	the energy process of nitrate reduction was studied in the typical soil denitrifying cultures of pseudomonas denitrificans by mass spectrometry. these microorganisms differed in certain characteristics of the process from the cultures of sporogenic soil denitrifying bacteria belonging to the bacillus genus. the rate of denitrification by ps. denitrificans was very high; as the result, losses of 15n from the medium exceeded 80--90%. ammonia was not produced as the final product of nitrate reducti ...	1980	7393007
studies on cyclopropane fatty acid synthesis. effect of carbon source and oxygen tension on cyclopropane fatty acid synthetase activity in pseudomonas denitrificans.	the cyclopropane fatty acid, methylene hexadecanoic acid, constituted from 1% to upwards of 30% of the total lipid fatty acids of the bacterium, pseudomonas denitrificans. the amount of this component varied along with the levels of the enzyme, cyclopropane synthetase (unsaturated-phospholipid methyltransferase, ec 2.1.1.16). when p. denitrificans was grown on succinate in a culture medium saturated with oxygen, cyclopropane synthetase remained repressed while cell densities were low. as cell de ...	1980	7459362
biocontrol: bacillus penetrans and related parasites of nematodes.	bacillus penetrans mankau, 1975, previously described as duboscqia penetrans thorne 1940, is a candidate agent for biocontrol of nematodes. this review considers the life stages of this bacterium: vegetative growth phase, colony fragmentation, sporogenesis, soil phase, spore attachment, and penetration into larvae of root-knot nematodes. the morphology of the microthallus colonies and the unusual external features of the spore are discussed. taxonomic affinities with the actinomycetes, particula ...	1980	19300701
pseudomonas denitrificans meningitis.	an elderly male patient with pseudomonas denitrificans bacteremia and meningitis is described. the antimicrobial susceptibility and minimum criteria necessary for the identification of this unusual and rare human pathogen are discussed.	1981	7240392
studies on cyclopropane fatty acid synthesis. correlation between the state of reduction of respiratory components and the accumulation of methylene hexadecanoic acid by pseudomonas denitrificans.	a delay in the onset of accumulation of methylene hexadecanoic acid could be engendered in pseudomonas denitrificans growing under limited oxygen conditions when the concentration of citrate but not the concentration of succinate in the medium was increased from 0.1 to 0.5%. ascorbate, which specifically reduced a cytochrome component possessing a maximum absorbance at 551 nm, partially inhibited the accumulation of methylene hexadecanoic acid under conditions which otherwise led to maximal prod ...	1981	7284425
fluorescein diacetate hydrolysis as a measure of total microbial activity in soil and litter.	spectrophotometric determination of the hydrolysis of fluorescein diacetate (fda) was shown to be a simple, sensitive, and rapid method for determining microbial activity in soil and litter. fda hydrolysis was studied in soil and straw incubated for up to 3 h. hydrolysis was found to increase linearly with soil addition. fda hydrolysis by pure cultures of fusarium culmorum increased linearly with mycelium addition both in shake cultures and after inoculation into sterile soil. fda hydrolysis by ...	1982	16346026
[characteristics of nitroreduction as the key stage in the microbial destruction of aromatic nitro compounds].	the reduction of nitrogroups of 2,4,6-trinitrotoluene (tnt) and other nitroaromatic compounds under the influence of pseudomonas denitrificans and escherichia coli enzymes was investigated. quantitative measurements of the immediate stable products of tnt reduction showed that its reducing attack increased with bacterial age. however, preferential reduction of the nitrogroup in position 2 was typical of bacterial cells of any age, being maintained at ph 5.5 to 7.8. the bacterial reduction in vit ...	1983	6353406
heterotrophic nitrification among denitrifiers.	twelve denitrifying bacteria representing six genera were tested for an ability to nitrify pyruvic oxime heterotrophically. six of these bacteria exhibited appreciable nitrification activity, yielding as much as 5.8 mm nitrite and little or no nitrate when grown in a mineral salts medium containing 7 mm pyruvic oxime and 0.05% yeast extract. of the six active bacteria, four (pseudomonas denitrificans, pseudomonas aeruginosa, and two strains of pseudomonas fluorescens) could grow on yeast extract ...	1984	6721486
dependence of betaine stimulation of vitamin b(12) overproduction on protein synthesis.	the betaine-stimulated differential synthesis of vitamin b(12), i.e., the increase in b(12) per increase in dry cell weight, by pseudomonas denitrificans was inhibited by rifampin and chloramphenicol but not by benzylpenicillin and carbenicillin at concentrations of antibiotic that inhibit growth. the level of the first enzyme of corrin (and porphyrin) biosynthesis, delta-aminolevulinic acid synthetase, was decreased to a much greater degree by rifampin and chloramphenicol than by the penicillin ...	1984	16346536
the tertiary structure of azurin from pseudomonas denitrificans as determined by cu resonant diffraction using synchrotron radiation.	the structure of pseudomonas denitrificans azurin has been solved at 3.0 a resolution by film data collection methods using synchrotron radiation. bijvoet pairs of reflections were collected using 8.98 kev radiation where both delta f' and delta f", the real and imaginary corrections to azurin's cu prosthetic group scattering, respectively, are large, and using 8.00 kev radiation where these corrections are smaller. the cu atom was located by difference patterson syntheses and used to phase the ...	1987	3656452
activation by monovalent cations of dissimilatory nitrate reductase in the cells of pseudomonas denitrificans.	cellular activity of nitrate reductase in pseudomonas denitrificans which had been grown under denitrifying conditions was increased several times upon incubation of cell suspension with monovalent cations. the enhancement of nitrate reductase activity caused by monovalent cations was ascribed to the activation of the enzyme, since the membrane fraction isolated from the cells after the cation treatment retained the elevated levels of enzyme activity. however, monovalent cations had no effect wh ...	1988	3421984
the effect of thiosulphate and other inhibitors of autotrophic nitrification on heterotrophic nitrifiers.	it has been found that heterotrophic nitrification by thiosphaera pantotropha can be inhibited by thiosulphate in batch and chemostat cultures. allythiourea and nitrapyrin, both classically considered to be specific inhibitors of autotrophic nitrification, inhibited nitrification by tsa. pantotropha in short-term experiments with resting cell suspensions. hydroxylamine inhibited ammonia oxidation in chemostat cultures, but was itself fully oxidized. thus the total nitrification rate for the cult ...	1989	2515797
cloning and analysis of genes involved in coenzyme b12 biosynthesis in pseudomonas denitrificans.	cobalamin synthesis probably requires 20 to 30 different enzymatic steps. pseudomonas putida and agrobacterium tumefaciens mutants deficient in cobalamin synthesis (cob have been isolated. in p. putida, cob mutants were identified as being unable to use ethanolamine as a source of nitrogen in the absence of added cobalamin (deamination of ethanolamine requires coenzyme b12 as a cofactor). in a. tumefaciens, cob mutants were simply screened for their reduced cobalamin synthesis. a genomic library ...	1989	2536665
purification and characterization of s-adenosyl-l-methionine: uroporphyrinogen iii methyltransferase from pseudomonas denitrificans.	s-adenosyl-l-methionine:uroporphyrinogen iii methyltransferase (sumt), the enzyme of the cobalamin biosynthetic pathway which catalyzes c methylation of uroporphyrinogen iii, was purified about 150-fold to homogeneity from extracts of a recombinant strain of pseudomonas denitrificans derived from a cobalamin-overproducing strain by ammonium sulfate fractionation, anion-exchange chromatography, and hydroxyapatite chromatography. the purified protein has an isoelectric point of 6.4 and molecular w ...	1989	2546914
aerobic denitrification in various heterotrophic nitrifiers.	various heterotrophic nitrifiers have been tested and found to also be aerobic denitrifiers. the simultaneous use of two electron acceptors (oxygen and nitrate) permits these organisms to grow more rapidly than on either single electron acceptor, but generally results in a lower yield than is obtained on oxygen, alone. one strain, formerly known as "pseudomonas denitrificans", was grown in the chemostat and shown to achieve nitrification rates of up to 44 nmol nh3 min-1 mg protein-1 and denitrif ...	1989	2619286
purification and characterization of cobyrinic acid a,c-diamide synthase from pseudomonas denitrificans.	cobyrinic acid a,c-diamide synthase, which catalyzes the conversion of cobyrinic acid to cobyrinic acid a,c-diamide via the intermediate formation of cobyrinic acid c-monoamide, was purified 155-fold to homogeneity from extracts of a recombinant strain of pseudomonas denitrificans by high-performance liquid chromatography. the enzyme has an apparent molecular weight of 86,000 and consists of two identical subunits of mr 45,000, as estimated by gel electrophoresis under denaturing conditions. ste ...	1990	2172209
assay and purification of s-adenosyl-l-methionine:precorrin-2 methyltransferase from pseudomonas denitrificans.	s-adenosyl-l-methionine:precorrin-2 methyltransferase (sp2mt), which catalyzes the c-20 methylation of precorrin-2 to precorrin-3, was purified to homogeneity from extracts of a recombinant strain of pseudomonas denitrificans derived from a cobalamin-overproducing strain. ammonium sulfate fractionation followed by chromatography on deae-trisacryl, hydroxyapatite, and mono q hr purified the enzyme about 110-fold, with a 28% yield. for enzyme purification and characterization, a coupled-enzyme ass ...	1990	2172210
nucleotide sequence of a pseudomonas denitrificans 5.4-kilobase dna fragment containing five cob genes and identification of structural genes encoding s-adenosyl-l-methionine: uroporphyrinogen iii methyltransferase and cobyrinic acid a,c-diamide synthase.	a 5.4-kilobase dna fragment carrying pseudomonas denitrificans cob genes has been sequenced. the nucleotide sequence and genetic analysis revealed that this fragment carries five different cob genes (coba to cobe). four of these genes present the characteristics of translationally coupled genes. coba has been identified as the structural gene of s-adenosyl-l-methionine:uroporphyrinogen iii methyltransferase (sumt) because the encoded protein has the same nh2 terminus and molecular weight as thos ...	1990	2211520
genetic and sequence analysis of an 8.7-kilobase pseudomonas denitrificans fragment carrying eight genes involved in transformation of precorrin-2 to cobyrinic acid.	a 8.7-kilobase dna fragment carrying pseudomonas denitrificans cob genes has been sequenced. the nucleotide sequence and the genetic analysis revealed that this fragment carries eight different cob genes (cobf to cobm). six of these genes have the characteristics of translationally coupled genes. cobi has been identified as s-adenosyl-l-methionine (sam):precorrin-2 methyltransferase structural gene because the encoded protein has the same nh2 terminus and molecular weight as those of the purifie ...	1990	2211521
biosynthesis of vitamin b12: isolation of precorrin-6x, a metal-free precursor of the corrin macrocycle retaining five s-adenosylmethionine-derived peripheral methyl groups.	delta-aminolevulinic acid and trimethylisobacteriochlorin are converted by cell-free protein preparations from pseudomonas denitrificans into a metal-free pigment, precorrin-6x. this pigment, which accumulates when the cell-free system lacks nadph, can be enzymically converted in high yield (greater than 50%) into hydrogenobyrinic acid by the complete enzyme preparation. double-labeling experiments establish that precorrin-6x carries five c-methyl groups, which appear at c-1, c-2, c-7, c-12 alph ...	1990	2247449
biosynthesis of vitamin b12: structure of precorrin-6x octamethyl ester.	13c-labeled precorrin-6x is biosynthesized by cell-free protein preparations from pseudomonas denitrificans in separate experiments using delta-amino[5-13c]levulinic acid and the corresponding delta-amino[4-13c]- and delta-amino[3-13c]levulinic acid-labeled forms in conjunction with s-[methyl-13c]adenosylmethionine for the latter two experiments. these labeled precorrin-6x samples, as their octamethyl esters, are studied by a range of nmr techniques. in addition, nuclear overhauser effect differ ...	1990	2247450
identification and quantitation of corrinoid precursors of cobalamin from pseudomonas denitrificans by high-performance liquid chromatography.	after initial pretreatment for removal of interfering substances, corrinoid precursors of cobalamin from cultures of pseudomonas denitrificans were separated by hplc with a gradient elution system. in this system, all the following compounds are separated in their dicyano form, and retention times are given: cobyrinic acid; cobyrinic acid a-amide; cobyrinic acid c-amide; cobyrinic acid g-amide; cobyrinic acid a,g-diamide; cobyrinic acid c,g-diamide; cobyrinic acid a,c-diamide; cobyrinic acid a,c ...	1990	2278386
a bifunctional protein from pseudomonas denitrificans carries cobinamide kinase and cobinamide phosphate guanylyltransferase activities.	the two consecutive activities of the cobalamin biosynthetic pathway that catalyze the conversion of cobinamide to cobinamide phosphate (cobinamide kinase) and of cobinamide phosphate to gdp-cobinamide (cobinamide phosphate guanylytransferase) were shown to be carried by the same protein in pseudomonas denitrificans. this bifunctional protein was purified to homogeneity by high-performance liquid chromatography of extracts of a recombinant strain of this microorganism, and the sequence of the fi ...	1991	1655696
nucleotide sequence and genetic analysis of a 13.1-kilobase-pair pseudomonas denitrificans dna fragment containing five cob genes and identification of structural genes encoding cob(i)alamin adenosyltransferase, cobyric acid synthase, and bifunctional cobinamide kinase-cobinamide phosphate guanylyltransferase.	a 13.1-kb dna fragment carrying pseudomonas denitrificans cob genes has been sequenced. the nucleotide sequence and genetic analysis revealed that this fragment contained five different cob genes named cobn to cobq and cobw. based on the similarity of nh2-terminal sequences and molecular weights of the purified cob proteins, cobq was identified as cobyric acid synthase, cobp was identified as a bifunctional enzyme exhibiting both cobinamide kinase and cobinamide phosphate guanylyltransferase act ...	1991	1655697
purification, characterization, and molecular cloning of s-adenosyl-l-methionine: uroporphyrinogen iii methyltransferase from methanobacterium ivanovii.	an s-adenosyl-l-methionine:uroporphyrinogen iii methyltransferase (sumt) activity has been identified in methanobacterium ivanovii and was purified 4,500-fold to homogeneity with a 38% yield. the enzyme had an apparent molecular weight of 58,200 by gel filtration and consisted of two identical subunits of mr 29,000, as estimated by gel electrophoresis under denaturing conditions. the km value for uroporphyrinogen iii was 52 nm. the enzyme catalyzed the two c-2 and c-7 methylation reactions conve ...	1991	1856165
primary structure, expression in escherichia coli, and properties of s-adenosyl-l-methionine:uroporphyrinogen iii methyltransferase from bacillus megaterium.	a bacillus megaterium dna fragment encoding s-adenosyl-l-methionine:uroporphyrinogen iii methyltransferase (sumt) activity was subcloned and sequenced. the encoded polypeptide showed more than 43.5% strict homology to pseudomonas denitrificans sumt (f. blanche, l. debussche, d. thibaut, j. crouzet, and b. cameron, j. bacteriol. 171:4222-4231, 1989). the b. megaterium polypeptide was overexpressed in escherichia coli, partially purified, and shown to exhibit, like p. denitrificans sumt, substrate ...	1991	1906874
biosynthesis of vitamin b12: stepwise amidation of carboxyl groups b, d, e, and g of cobyrinic acid a,c-diamide is catalyzed by one enzyme in pseudomonas denitrificans.	the cobalamin biosynthetic pathway enzyme that catalyzes amidation of 5'-deoxy-5'-adenosyl-cobyrinic acid a,c-diamide was purified to homogeneity from extracts of a recombinant strain of pseudomonas denitrificans by a four-column procedure. the purified protein had an isoelectric point of 5.6 and molecular weights of 97,300 as estimated by gel filtration and 57,000 as estimated by gel electrophoresis under denaturing conditions, suggesting that the active enzyme is a homodimer. stepwise edman de ...	1991	1917839
genetic and sequence analyses of a pseudomonas denitrificans dna fragment containing two cob genes.	a genetic analysis of a 12-kb dna fragment containing pseudomonas denitrificans cob genes was performed by transposon-mediated insertional mutagenesis. the nucleotide sequence and genetic analysis have shown that a 4.8-kb dna subfragment carried two cob genes (cobs and cobt). biochemical data concerning the complemented cobs and cobt mutants suggested that the cobs product was involved in cobalt insertion-mediating reactions and that the cobt product was involved in the transformation of precorr ...	1991	1917840
genetic analysis, nucleotide sequence, and products of two pseudomonas denitrificans cob genes encoding nicotinate-nucleotide: dimethylbenzimidazole phosphoribosyltransferase and cobalamin (5'-phosphate) synthase.	tn5 sp(r) transposons have been inserted into the 8-kb pseudomonas denitrificans dna fragment from complementation group d, which carries cob genes. genetic analysis and the nucleotide sequence revealed that only two cob genes (cobu and cobv) were found on this cob genomic locus. nicotinate-nucleotide: dimethylbenzimidazole phosphoribosyltransferase (ec 2.4.2.21) was assayed and purified to homogeneity from a p. denitrificans strain in which cobu and cobv were amplified. the purified enzyme was ...	1991	1917841
purification and partial characterization of cob(i)alamin adenosyltransferase from pseudomonas denitrificans.	cob(i)alamin adenosyltransferase (ec 2.5.1.17) was purified to homogeneity from extracts of a pseudomonas denitrificans recombinant strain and sequenced at its n terminus. it is a homodimer (each unit with an mr of 28,000) encoded by cobo. the enzyme adenosylated all of the corrinoids isolated from this microorganism but did not adenosylate cobyrinic acid.	1991	1917862
precorrin-6x reductase from pseudomonas denitrificans: purification and characterization of the enzyme and identification of the structural gene.	precorrin-6x reductase, which catalyzes the nadph-dependent reduction of precorrin-6x to a dihydro derivative named precorrin-6y, was purified 14,300-fold to homogeneity with an 8% yield from extracts of a recombinant strain of pseudomonas denitrificans. precorrin-6y was identified by fast atom bombardment-mass spectrometry. it was converted in high yield (90%) to hydrogenobyrinic acid by cell-free protein preparations from p. denitrificans. for the purification and characterization of precorrin ...	1992	1732193
the final step in the biosynthesis of hydrogenobyrinic acid is catalyzed by the cobh gene product with precorrin-8x as the substrate.	the final enzymatic reaction in the conversion of precorrin-6x to hydrogenobyrinic acid by cell-free protein preparations from pseudomonas denitrificans was shown to be inhibited by hydrogenobyrinic acid. use was made of this property to prepare the last biosynthetic precursor of hydrogenobyrinic acid, named precorrin-8x. double-labeling experiments, mass spectrometry, and uv-visible light spectroscopy studies established that precorrin-8x was at the oxidation level of a corrin and differed from ...	1992	1732194
biosynthesis of vitamin b12 in pseudomonas denitrificans: the biosynthetic sequence from precorrin-6y to precorrin-8x is catalyzed by the cobl gene product.	a protein catalyzing methylation at c-5 and c-15 and decarboxylation of the acetic acid side chain at c-12 on precorrin-6y to yield precorrin-8x was purified to homogeneity from a recombinant strain of pseudomonas denitrificans. it was sequenced at the n terminus and shown to be encoded by the cobl gene.	1992	1732195
assay, purification, and characterization of cobaltochelatase, a unique complex enzyme catalyzing cobalt insertion in hydrogenobyrinic acid a,c-diamide during coenzyme b12 biosynthesis in pseudomonas denitrificans.	hydrogenobyrinic acid a,c-diamide was shown to be the substrate of cobaltochelatase, an enzyme that catalyzes cobalt insertion in the corrin ring during the biosynthesis of coenzyme b12 in pseudomonas denitrificans. cobaltochelatase was demonstrated to be a complex enzyme composed of two different components of m(r) 140,000 and 450,000, which were purified to homogeneity. the 140,000-m(r) component was shown to be coded by cobn, whereas the 450,000-m(r) component was composed of two polypeptides ...	1992	1429466
purification and characterization of cob(ii)yrinic acid a,c-diamide reductase from pseudomonas denitrificans.	an nadh-dependent flavoenzyme exhibiting cob(ii)yrinic acid a,c-diamide reductase activity was purified 6,300-fold to homogeneity from pseudomonas denitrificans and sequenced at its n terminus. this enzyme of the cobalamin biosynthetic pathway reduced to the co(i) state all of the co(ii)-corrinoids isolated from this microorganism.	1992	1429467
construction of a broad-host-range non-mobilizable stable vector carrying rp4 par-region.	plasmid pxl1635 was constructed from the already segregationally stable incp-derived prk290. plasmid pxl1635 should be suitable for industrial and environmental uses in gram- bacteria since (i) it contains the par fragment from rp4 which increases its stability in pseudomonas denitrificans, a cobalamin-producing and industrially used bacterium, and (ii) the rk2 orit has been deleted, leading to a non-mobilizable plasmid.	1992	1544566
inhibition of existing denitrification enzyme activity by chloramphenicol.	chloramphenicol completely inhibited the activity of existing denitrification enzymes in acetylene-block incubations with (i) sediments from a nitrate-contaminated aquifer and (ii) a continuous culture of denitrifying groundwater bacteria. control flasks with no antibiotic produced significant amounts of nitrous oxide in the same time period. amendment with chloramphenicol after nitrous oxide production had begun resulted in a significant decrease in the rate of nitrous oxide production. chloram ...	1992	1622247
biosynthesis of the corrin macrocycle of coenzyme b12 in pseudomonas denitrificans.	studies with cell-free protein preparations from a series of recombinant strains of pseudomonas denitrificans demonstrated that precorrin-3 is converted into a further trimethylated intermediate, named precorrin-3b, along the pathway to coenzyme b12. it was then shown that the part of the pathway from precorrin-3 (called precorrin-3a hereafter) to precorrin-6x involves three intermediates, precorrin-3b, precorrin-4, and precorrin-5. precorrin-3b was isolated in its native (reduced) as well as it ...	1993	8226690
reduction of nitric oxide by denitrifying bacteria.	two heterotrophic denitrifying bacteria, paracoccus denitrificans and pseudomonas denitrificans, have been shown to utilize nitric oxide (no) as a terminal electron acceptor and succinate, yeast extract, and heat/alkali pretreated municipal sewage sludge as carbon and energy sources. complete removal of no (0.50%) from a feed gas sparged into the cultures was observed. it is suggested that reduction of no may be a common feature of denitrifying bacteria and that a microbial process to dispose of ...	1993	8323271
simultaneous nitrification and denitrification using immobilized microorganisms.	nitrogen removal from wastewaters is a multiple step process in which nitrification is often a problem due to the slow growth rates of the nitrifying bacteria. by immobilization of these bacteria, nitrification can be efficiently accomplished in compact reactors. in this paper, the possibilities of integrated nitrification and denitrification within a single reactor system are evaluated. two main systems are studied: a) nitrosamines europaea and pseudomonas denitrificans co-immobilized in a a ge ...	1993	8399972
biosynthesis of vitamin b12. discovery of the enzymes for oxidative ring contraction and insertion of the fourth methyl group.	in the vitamin b12 biosynthetic pathway the enzymes responsible for the conversion of precorrin-3 to precorrin-4 have been identified as the gene products of cobg and cobj from pseudomonas denitrificans. cobg catalyzes the oxidation of precorrin-3 to precorrin-3x (a hydroxy lactone) whereas cobj is a sam-dependent c-17 methyl transferase and is necessary for ring contraction. a mechanism for ring contraction is proposed.	1993	8405386
characterization of the cobalamin (vitamin b12) biosynthetic genes of salmonella typhimurium.	salmonella typhimurium synthesizes cobalamin (vitamin b12) de novo under anaerobic conditions. of the 30 cobalamin synthetic genes, 25 are clustered in one operon, cob, and are arranged in three groups, each group encoding enzymes for a biochemically distinct portion of the biosynthetic pathway. we have determined the dna sequence for the promoter region and the proximal 17.1 kb of the cob operon. this sequence includes 20 translationally coupled genes that encode the enzymes involved in parts i ...	1993	8501034
cloning, sequencing and overexpression of coba which encodes atp:corrinoid adenosyltransferase in salmonella typhimurium.	the coba gene of salmonella typhimurium was cloned, sequenced and overexpressed. a 990-bp hpai-saci fragment was cloned into the multiple cloning site of plasmid psu19, an intermediate-copy-number vector. dna sequence analysis established that coba is 588 bp in length and codes for a protein with a predicted molecular weight of 21.7 kda. however, the coba protein expressed from the t7 promoter migrated as a 25-kda protein on sds-polyacrylamide gels. a high degree of identity at the amino acid se ...	1993	7916712
sequences of the cobalamin biosynthetic genes cobk, cobl and cobm from rhodococcus sp. ni86/21.	sequence analysis of a 5753-bp genomic fragment of rhodococcus sp. ni86/21 revealed the presence of three homologues of known cobalamin biosynthetic genes. one of these genes encodes a protein showing strong homology with the precorrin-6x reductase (cobk) of pseudomonas denitrificans. in addition, the rhodococcal homologue of the corrin methyltransferases, cobm from p. denitrificans and cbif from salmonella typhimurium, was identified. the protein deduced from a third rhodococcus gene aligns wel ...	1994	8200543
the cobt gene of salmonella typhimurium encodes the namn: 5,6-dimethylbenzimidazole phosphoribosyltransferase responsible for the synthesis of n1-(5-phospho-alpha-d-ribosyl)-5,6-dimethylbenzimidazole, an intermediate in the synthesis of the nucleotide loop of cobalamin.	we present in vitro evidence which demonstrates that cobt is the nicotinate nucleotide:5,6-dimethylbenzimidazole (dmb) phosphoribosyltransferase (ec 2.4.2.21) that catalyzes the synthesis of n1-(5-phospho-alpha-d-ribosyl)-5,6-dimethylbenzimidazole, a biosynthetic intermediate of the pathway that assembles the nucleotide loop of cobalamin in salmonella typhimurium. mutants previously isolated as dmb auxotrophs are shown by physical and genetic mapping studies and complementation studies to carry ...	1994	8206834
nitrile hydratase gene from rhodococcus sp. n-774 requirement for its downstream region for efficient expression.	for improvement of the production of nitrile hydratase (nhase) from rhodococcus sp. n-774 by recombinant dna techniques, several plasmids, each of which had a deletion of the upstream or downstream region of the genes encoding the alpha and beta subunits of nhase, were constructed. enzyme assays of recombinant r. rhodochrous and escherichia coli cells showed that a downstream region of the nhase genes was indispensable for the production of active nhase in both cells, but for the production of t ...	1994	7765511
genetics and enzymology of the b12 pathway.	the chemical complexity of vitamin b12 suggests that its formation may involve a large number of enzymic steps. however, until recently, little was known of the number, mechanism and stereochemical course of the many enzymic interconversions that are essential to vitamin b12 biosynthesis. in response to this the french groups led by francis blanche and joel crouzet have carried out extensive investigations into the genetic and biochemical organization of this remarkable biosynthetic pathway. thr ...	1994	7842856
recent studies of enzymically controlled steps in b12 biosynthesis.	the acquisition and sequencing of the genes encoding the enzymes for vitamin b12 biosynthesis in salmonella typhimurium and pseudomonas denitrificans has dramatically altered the direction of research on the pathway from uroporphyrinogen iii to the corrinoids. through a combination of molecular biology, organic chemistry and nmr spectroscopy, logical progression along the sequence is being made. recent work from our laboratory is focused on the discovery and specificities of the methyltransferas ...	1994	7842859
metabolic pathway for biosynthesis of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) from 4-hydroxybutyrate by alcaligenes eutrophus.	various aerobic gram-negative bacteria have been examined for their ability to use 4-hydroxybutyrate and 1,4-butanediol as carbon source for growth. alcaligenes eutrophus strains h16, hf39, phb-4 and pseudomonas denitrificans 'morris' were not able to grow with 1,4-butanediol or 4-hydroxybutyrate. from a. eutrophus hf39 spontaneous primary mutants (e.g. sk4040) were isolated which grew on 4-hydroxybutyrate with doubling times of approximately 3 h. tn5::mob mutagenesis of mutant sk4040 led to the ...	1995	7851418
cloning, sequencing, and expression of the uroporphyrinogen iii methyltransferase coba gene of propionibacterium freudenreichii (shermanii).	we cloned, sequenced, and overexpressed coba, the gene encoding uroporphyrinogen iii methyltransferase in propionibacterium freudenreichii, and examined the catalytic properties of the enzyme. the methyltransferase is similar in mass (27 kda) and homologous to the one isolated from pseudomonas denitrificans. in contrast to the much larger isoenzyme encoded by the cysg gene of escherichia coli (52 kda), the p. freudenreichii enzyme does not contain the additional 22-kda peptide moiety at its n-te ...	1995	7883713
biosynthesis of porphyrins and related macrocycles, part 43. isolation and characterization of intermediates of coenzyme b12 biosynthesis, a cobyrinic acid triamide, the a,c-diamide and their co-(5'-deoxy-5'-adenosyl) derivatives, from propionibacterium shermanii.	vitamin b12 is synthesized by many different organisms, for example pseudomonas denitrificans (aerobic) and propionibacterium shermanii ('microaerophilic', or essentially anaerobic). the biosynthetic pathways in these two organisms show strong similarities but also some differences. there have been conflicting reports on where differences between these two organisms lie in the stages beyond the formation of the corrin macrocycle. characterization of intermediates in the pathway will help resolve ...	1995	9383456
reduction of nitrate and nitrite in a cyclically operated continuous biological reactor.	biological reduction of nitrate and nitrite was studied with a continuously operated cyclic reactor. the medium was fed to the reactor during the first phase of the cycle, and the effluent was drawn from the reactor during the third phase of the cycle; reaction occurred throughout the cycle. the process was described mathematically based on kinetic expressions revealed in an independent study. the model equations were subjected to detailed analysis with numerical codes based on the bifurcation t ...	1995	18623275
fundamental denitrification kinetic studies with pseudomonas denitrificans.	fundamental kinetic studies on the reduction of nitrate, nitrite, and their mixtures were performed with a strain of pseudomonas denitrificans (atcc 13867). methanol served as the carbon source and was supplied in excess (2:1 mole ratio relative to nitrate and/or nitrite). nitrate and nitrite served as terminal electron acceptors as well as sources of nitrogen for biomass synthesis. the results were explained under the assumption that respiration is a growth-associated process. it was found that ...	1995	18623364
effect of chloramphenicol on denitrification in flexibacter canadensis and "pseudomonas denitrificans".	it was recently reported that chloramphenicol inhibits existing denitrification enzyme activity in sediments and carbon-starved cultures of "pseudomonas denitrificans." therefore, we studied the effect of chloramphenicol on denitrification by flexibacter canadensis and "p. denitrificans." production of n(inf2)o from nitrate by f. canadensis cells decreased as the concentration of chloramphenicol was increased, and 10.0 mm chloramphenicol completely inhibited n(inf2)o production. "p. denitrifican ...	1995	16534926
identification and sequence analysis of genes involved in late steps in cobalamin (vitamin b12) synthesis in rhodobacter capsulatus.	a 6.4-kb region of a 6.8-kb bamhi fragment carrying rhodobacter capsulatus genes involved in late steps of cobalamin synthesis has been sequenced. the nucleotide sequence and genetic analysis revealed that this fragment contains eight genes arranged in at least three operons. five of these eight genes show homology to genes involved in the cobalamin synthesis of pseudomonas denitrificans and salmonella typhimurium. the arrangement of these homologous genes differs considerably in the three gener ...	1995	7635831
cloning and sequencing of some genes responsible for porphyrin biosynthesis from the anaerobic bacterium clostridium josui.	the 6.2-kbp dna fragment encoding the enzymes in the porphyrin synthesis pathway of a cellulolytic anaerobe, clostridium josui, was cloned into escherichia coli and sequenced. this fragment contained four hem genes, hema, hemc, hemd, and hemb, in order, which were homologous to the corresponding genes from e. coli and bacillus subtilis. a typical promoter sequence was found only upstream of hema, suggesting that these four genes were under the control of this promoter as an operon. the hema and ...	1995	7665501
biosynthesis of vitamin b12: the preparative multi-enzyme synthesis of precorrin-3a and 20-methylsirohydrochlorin (a 2,7,20-trimethylisobacteriochlorin).	the bacillus subtilis genes hemb, hemc and hemd, encoding respectively the enzymes porphobilinogen synthase, hydroxymethylbilane synthase and uroporphyrinogen iii synthase, have been expressed in escherichia coli using a single plasmid construct. an enzyme preparation from this source converts 5-aminolaevulinic acid (ala) preparatively and in high yield into uroporphyrinogen iii. the pseudomonas denitrificans genes coba and cobi, encoding respectively the enzymes s-adenosyl-l-methionine:uroporph ...	1996	8546704
salmonella typhimurium cobalamin (vitamin b12) biosynthetic genes: functional studies in s. typhimurium and escherichia coli.	in order to study the salmonella typhimurium cobalamin biosynthetic pathway, the s. typhimurium cob operon was isolated and cloned into escherichia coli. this approach has given the new host of the cob operon the ability to make cobalamins de novo, an ability that had probably been lost by this organism. in total, 20 genes of the s. typhimurium cob operon have been transferred into e. coli, and the resulting recombinant strains have been shown to produce up to 100 times more corrin than the pare ...	1996	8550510