| oscillations of nitric oxide concentration in the perturbed denitrification pathway of paracoccus denitrificans. | the metabolism of nitric oxide in paracoccus denitrificans has been studied using a clark-type electrode. the uncoupler carbonyl cyanide m-chlorophenylhydrazone (cccp) and the sh reagent n-ethylmaleimide, both of which released nitric oxide from cells respiring nitrite, were found to be efficient inhibitors of nitric oxide reductase activity. control experiments with another uncoupler, pentachlorophenol, showed that the inhibitory effect of cccp was not the result of a decrease in membrane poten ... | 1992 | 1325776 |
| characterization of mutant forms of the quinoprotein methanol dehydrogenase lacking an essential calcium ion. | methanol dehydrogenase (mdh) from methylobacterium extorquens, methylophilus methylotrophus, paracoccus denitrificans and hyphomicrobium x all contained a single atom of ca2+ per alpha 2 beta 2 tetramer. the role of ca2+ was investigated using the mdh from methylobacterium extorquens. this was shown to be similar to the mdh from hyphomicrobium x in having 2 mol of prosthetic group (pyrroloquinoline quinine; pqq) per mol of tetramer, the pqq being predominantly in the semiquinone form. mdh isolat ... | 1992 | 1332681 |
| electronic and vibrational spectroscopy of the cytochrome c:cytochrome c oxidase complexes from bovine and paracoccus denitrificans. | the 1:1 complex between horse heart cytochrome c and bovine cytochrome c oxidase, and between yeast cytochrome c and paracoccus denitrificans cytochrome c oxidase have been studied by a combination of second derivative absorption, circular dichroism (cd), and resonance raman spectroscopy. the second derivative absorption and cd spectra reveal changes in the electronic transitions of cytochrome a upon complex formation. these results could reflect changes in ground state heme structure or changes ... | 1992 | 1338946 |
| cytochrome c550 from thiobacillus versutus: cloning, expression in escherichia coli, and purification of the heterologous holoprotein. | the gene coding for cytochrome c550 from thiobacillus versutus, cyca, has been cloned and sequenced. it codes for a protein of 134 amino acids plus a 19-amino-acid-long signal peptide. both coding and noncoding dna sequences of the clone are homologous to the paracoccus denitrificans dna sequence. an expression vector was constructed by cloning the cyca gene directly behind the lac promoter of puc. the cyca gene was expressed in escherichia coli under semianaerobic conditions, and mature holo-cy ... | 1992 | 1339423 |
| potentiometric and spectral studies with the two-subunit cytochrome aa3 from paracoccus denitrificans. comparison with the 13-subunit beef heart enzyme. | previous work from this laboratory has revealed a complex and interactive redox behavior for the active metal centers in beef heart cytochrome aa3. all of these centers are contained in two of the 13 subunits which make up the enzyme. the isolated cytochrome aa3 of paracoccus denitrificans contains only two subunits. the purpose of the current investigation was to see if the complex redox behavior is dependent on the presence of the additional 11 peptides that are present in the mammalian enzyme ... | 1991 | 1655082 |
| comparison of energy-transducing capabilities of the two- and three-subunit cytochromes aa3 from paracoccus denitrificans and the 13-subunit beef heart enzyme. | in the accompanying paper, we have shown that the two-subunit cytochrome aa3 isolated from paracoccus denitrificans displays the same kind of complex and interactive redox behavior as the 13-subunit cytochrome aa3 from beef heart. therefore, the redox characteristics are not dependent on the additional 11 subunits. in the current work, we have examined the energy-transducing capabilities of both the two- and three-subunit enzymes obtained from paracoccus denitrificans in relation to that of the ... | 1991 | 1655083 |
| isolation and characterization of the moxj, moxg, moxi, and moxr genes of paracoccus denitrificans: inactivation of moxj, moxg, and moxr and the resultant effect on methylotrophic growth. | by using the moxf gene encoding the large fragment of methanol dehydrogenase as a probe, a downstream linked chromosomal fragment was isolated from a genomic bank of paracoccus denitrificans. the nucleotide sequence of the fragment was determined and revealed the 3' part of moxf, four additional open reading frames, and the 5' part of a sixth one. the organization and deduced amino acid sequences of the first three frames downstream from moxf were found to be largely homologous to the moxj, moxg ... | 1991 | 1657871 |
| a method for introduction of unmarked mutations in the genome of paracoccus denitrificans: construction of strains with multiple mutations in the genes encoding periplasmic cytochromes c550, c551i, and c553i. | a new suicide vector, prvs1, was constructed to facilitate the site-directed introduction of unmarked mutations in the chromosome of paracoccus denitrificans. the vector was derived from suicide vector pgrpd1, which was equipped with the lacz gene encoding beta-galactosidase. the reporter gene was found to be a successful screening marker for the discrimination between plasmid integrant strains and mutant strains which had lost the plasmid after homologous recombination. suicide vectors pgrpd1 a ... | 1991 | 1657872 |
| isolation, sequencing, and mutagenesis of the gene encoding cytochrome c553i of paracoccus denitrificans and characterization of the mutant strain. | the periplasmically located cytochrome c553i of paracoccus denitrificans was purified from cells grown aerobically on choline as the carbon source. the purified protein was digested with trypsin to obtain several protein fragments. the n-terminal regions of these fragments were sequenced. on the basis of one of these sequences, a mix of 17-mer oligonucleotides was synthesized. by using this mix as a probe, the structural gene encoding cytochrome c553i (cycb) was isolated. the nucleotide sequence ... | 1991 | 1657873 |
| increase in spermine content coordinated with siderophore production in paracoccus denitrificans. | spermine is present in relatively low amounts in paracoccus denitrificans cultured aerobically in an ammonium succinate minimal salts medium supplemented with 50 microm iron(iii). however, in iron-deprived cultures [minimal salts medium containing 0.5 microm iron(iii)], spermine content increases by an order of magnitude in coordination with the well-known responses to iron derivation, e.g., derepression of siderophore synthesis and siderophore excretion. when iron-deprived cultures exhibiting b ... | 1991 | 1826103 |
| identification of the dna region responsible for sulfur-oxidizing ability of thiosphaera pantotropha. | for the identification of the dna region responsible for the sulfur-oxidizing ability (sox) of thiosphaera pantotropha, we used previously isolated tn5-mob insertional sox- mutants. for seven mutants, the tn5-mob insertion was localized on the chromosome rather than on the megaplasmids phg41 or phg42 by using the tn5-mob-harboring vehicle psup5011 as probe. the specific insertion of tn5-mob into a sox gene was determined for one sox- mutant, strain tp19. an 18-kb ecori fragment was cloned in esc ... | 1991 | 1938925 |
| paracoccus denitrificans cytochrome c1 gene replacement mutants. | we describe the construction and characterization of gene replacement mutants for the respiratory chain component cytochrome c1 in the bacterium paracoccus denitrificans. its structural gene (fbcc) was inactivated by insertion of the kanamycin resistance gene, introduced into a suicide vector, and conjugated into paracoccus; chromosomal mutants obtained by homologous recombination were selected by antibiotic resistance screening and further characterized biochemically. they showed the complete s ... | 1990 | 2158969 |
| cloning and sequencing of the gene encoding the 72-kilodalton dehydrogenase subunit of alcohol dehydrogenase from acetobacter aceti. | a genomic library of acetobacter aceti dna was constructed by using a broad-host-range cosmid vector. complementation of a spontaneous alcohol dehydrogenase-deficient mutant resulted in the isolation of a plasmid designated paa701. subcloning and deletion analysis of paa701 limited the region that complemented the deficiency in alcohol dehydrogenase activity of the mutant. the nucleotide sequence of this region was determined and showed that this region contained the full structural gene for the ... | 1989 | 2722742 |
| cytochrome c oxidase from paracoccus denitrificans: both hemes are located in subunit i. | the two-subunit cytochrome c oxidase from paracoccus denitrificans has been sequentially digested with chymotrypsin and staphylococcus aureus v8 protease. the smaller subunit of the enzyme (apparent mr 32,000) was split into numerous peptides that were removed by anion-exchange hplc. the larger subunit was only digested to a limited extent (from an apparent mr 45,000 to mr 43,000), and the spectral properties were preserved relative to the native enzyme (a reduced minus oxidized difference spect ... | 1988 | 2842784 |
| dimeric porin from paracoccus denitrificans. | paracoccus denitrificans was shown to contain a 33,000-dalton porin, which produced pores of large (1.6 to 1.8 nm) diameter. cross-linking studies showed that the porin existed as dimers in the outer membrane. | 1985 | 2984184 |
| isolation and nucleotide sequence of the methanol dehydrogenase structural gene from paracoccus denitrificans. | a genomic clone bank of paracoccus denitrificans dna has been constructed in the expression vector set pex1, pex2, and pex3. screening of this clone bank with antibodies raised against p. denitrificans methanol dehydrogenase resulted in the isolation of a clone, pnh3, that synthesized methanol dehydrogenase cross-reactive proteins. the nucleotide sequence of the p. denitrificans dna fragment inserted in this clone has been determined and shown to contain the full methanol dehydrogenase structura ... | 1987 | 3114231 |
| loss of n2o reductase activity as an explanation for poor growth of pseudomonas aeruginosa on n2o. | n2o uptake activity of cells and n2o reductase activity of the soluble fraction from denitrifying bacteria were assayed. pseudomonas aeruginosa strains pao1 and p1 lost most of their n2o uptake activity and the ability to grow well on n2o within 2 to 5 h after exposure to n2o. extensive loss of n2o reductase activity accompanied the nearly complete loss of n2o uptake activity under n2o. paracoccus denitrificans retained much, but not all, of both activities and the ability to grow vigorously on ... | 1987 | 3118806 |
| demonstration of ferric l-parabactin-binding activity in the outer membrane of paracoccus denitrificans. | under low-iron conditions, paracoccus denitrificans excretes a catecholamine siderophore, l-parabactin, to sequester and utilize iron. in this report, we demonstrate the presence of stereospecific high-affinity ferric l-parabactin-binding activity associated with p. denitrificans membranes grown in low-iron medium. isolated outer membrane components were shown to be three to four times higher in specific activity for ferric l-parabactin. the same amount of binding activity existed whether or not ... | 1988 | 3403511 |
| electron transfer flavoprotein from methylophilus methylotrophus: properties, comparison with other electron transfer flavoproteins, and regulation of expression by carbon source. | when grown on methylated amines as a carbon source, methylophilus methylotrophus synthesizes an electron transfer flavoprotein (etf) which is the natural electron acceptor of trimethylamine dehydrogenase. it is composed of two dissimilar subunits of 38,000 and 42,000 daltons and 1 mol of flavin adenine dinucleotide. it was reduced by trimethylamine dehydrogenase to a stable anionic semiquinone form, which could not be converted, either enzymatically or chemically, to the fully reduced dihydroqui ... | 1986 | 3711024 |
| the primary structures of pseudomonas am1 amicyanin and pseudoazurin. two new sequence classes of blue copper proteins. | the amino acid sequences of two blue copper proteins from the pink facultative methylotroph pseudomonas am1 (n.c.i.b. 9133) were determined. they each consist of a single polypeptide chain and bind one copper atom. amicyanin contains 99 and pseudoazurin 123 residues. copper-binding sites, consisting of the side chains of two histidine, one cysteine and one methionine residues, can be recognized in each protein by analogy with azurin and plastocyanin, but the spacings of the ligand residues are d ... | 1985 | 4091802 |
| a two-subunit cytochrome c oxidase (cytochrome aa3) from paracoccus dentrificans. | cytochrome c oxidase (ferrocytochrome c: oxygen oxidoreductase, ec 1.9.3.1) was purified from the cytoplasmic membrane of the bacterium paracoccus denitrificans. the enzyme contains two heme groups (a and a3) and two copper atoms per minimal unit, oxidizes mammalian cytochrome c at a high rate, and, when incorporated into liposomes, generates an electrochemical proton gradient during cytochrome c oxidation. sodium dodecyl sulfate/polyacrylamide gel electrophoresis reveals only two subunits of ap ... | 1980 | 6244543 |
| 19f-nuclear magnetic resonance: measurements of [o2] and ph in biological systems. | 19f-nuclear magnetic resonance (nmr) has been used to determine both intracellular ph and oxygen concentrations in cell suspensions. oxygen concentrations in paracoccus denitrificans and insulinoma cells, rinm5f, in the nmr probe can be monitored directly by 1/t1 measurements of perfluorotripropylamine (ftpa)/lecithin emulsion added to the suspensions. with ftpa oxygen monitoring, we investigated the relative aeration capabilities of two types of nmr chambers. both normal and transformed eucaryo ... | 1988 | 3345331 |
| physiological regulation of paracoccus denitrificans methanol dehydrogenase synthesis and activity. | an enzyme-linked immunosorbent assay and a whole-cell activity assay were developed which allowed detection of methanol dehydrogenase (mdh) of paracoccus denitrificans with increased sensitivity. by these methods, it was shown that mdh was not induced by its natural substrate, methanol. relief from a catabolite repression-like mechanism seemed responsible for low-level mdh synthesis, while product induction was the hypothesized mechanism for synthesis of high amounts of mdh. in the latter proces ... | 1988 | 3042759 |
| partial purification and characterization of glutaryl-coenzyme a dehydrogenase, electron transfer flavoprotein, and electron transfer flavoprotein-q oxidoreductase from paracoccus denitrificans. | glutaryl-coenzyme a (coa) dehydrogenase and the electron transfer flavoprotein (etf) of paracoccus denitrificans were purified to homogeneity from cells grown with glutaric acid as the carbon source. glutaryl-coa dehydrogenase had a molecular weight of 180,000 and was made up of four identical subunits with molecular weights of about 43,000 each of which contained one flavin adenine dinucleotide molecule. the enzyme catalyzed an oxidative decarboxylation of glutaryl-coa to crotonyl-coa, was maxi ... | 1985 | 2991202 |
| mode of action of copper complexes of some 2,2'-bipyridyl analogs on paracoccus denitrificans. | copper complexes of 2,2'-bipyridyl and related compounds and cuso4 inhibited the growth of paracoccus denitrificans. the copper(i) complex of 2,9-dimethyl-1,10-phenanthroline [cu(dmp)2no3] showed the highest activity, whereas the copper(ii) complex of 1,10-phenanthroline and cuso4 inhibited the growth to a lesser extent. the uncomplexed ligands (1,10-phenanthroline and 2,9-dimethyl-1,10-phenanthroline) showed little activity, but in the presence of noninhibitory amounts of cuso4 this activity in ... | 1980 | 6778379 |
| consensus structure and evolution of 5s rrna. | a consensus structure model of 5s rrna presenting all conserved nucleotides in fixed positions has been deduced from the primary and secondary structure of 71 eubacterial, archaebacterial, eukaryotic cytosolic and organellar molecules. phylogenetically related groups of molecules are characterized by nucleotide deletions in helices iii, iv and v, and by potential base pair interactions in helix iv. the group-specific deletions are correlated with the early branching pattern of a dendrogram calcu ... | 1983 | 6835839 |
| investigation by electron paramagnetic resonance spectroscopy of the molybdenum centre of respiratory nitrate reductase from paracoccus denitrificans. | the molybdenum centre of respiratory nitrate reductase from paracoccus denitrificans has been investigated by e.p.r. spectroscopy of mo(v). in common with the centres of the analogous enzymes from escherichia coli and pseudomonas aeruginosa, it undergoes a ph- and anion-dependent transition between two different e.p.r. signal-giving species. comparison of the relevant e.p.r. parameters extracted with the help of computer simulations reveals ligation of the metal in the active centres of the thre ... | 1988 | 2844161 |
| separate binding sites for antimycin and mucidin in the respiratory chain of the bacterium paracoccus denitrificans and their occurrence in other denitrificans bacteria. | by means of the method of fluorimetric titration it has been shown that mucidin does not affect the attachment of antimycin to membranes from anaerobically grown paracoccus denitrificans. the fluorimetric titration with antimycin can be used in the determination of the amount of the cytochrome bc1 complex in the membrane. in cells inhibited with antimycin, the oxidation of cytochromes c was accompanied by the reduction of cytochrome b; in the presence of mucidin this effect did not take place. t ... | 1988 | 2844159 |
| control of respiration rate in non-growing cells of paracoccus denitrificans. | by means of fluorimetric measurement and by direct determination of intracellular nad+ and nadh contents, it was proved that the respiration rate of paracoccus denitrificans cells utilizing glucose is limited by processes preceding nadh oxidation in the respiratory chain, so that the membrane nadh dehydrogenase is not saturated by its substrate. in the separated membrane fraction on saturation with exogenous nadh the main limiting factor is represented by nadh: ubiquinone oxidoreductase. | 1987 | 2825653 |
| steady-state kinetic analysis of the quinoprotein methylamine dehydrogenase from paracoccus denitrificans. | a steady-state kinetic analysis was performed of the reaction of methylamine and phenazine ethosulphate (pes) with the quinoprotein methylamine dehydrogenase from paracoccus denitrificans. experiments with methylamine and pes as varied-concentration substrates produced a series of parallel reciprocal plots, and when the concentrations of these substrates were varied in a constant ratio a linear reciprocal plot of initial velocity against pes concentration was obtained. nearly identical values of ... | 1989 | 2775197 |
| deletion of the gene for subunit iii leads to defective assembly of bacterial cytochrome oxidase. | coiii is one of the major subunits in the mitochondrial and a bacterial cytochrome c oxidase, cytochrome aa3. it does not contain any of the enzyme's redox-active metal centres and can be removed from the enzyme without major changes in its established functions. we have deleted the coiii gene from paracoccus denitrificans. the mutant still expresses spectroscopically detectable enzyme almost as the wild-type, but its cytochrome c oxidase activity is much lower. from 50 to 80% of cytochrome a is ... | 1989 | 2555169 |
| kinetics of iron acquisition from ferric siderophores by paracoccus denitrificans. | the kinetics of iron accumulation by iron-starved paracoccus denitrificans during the first 2 min of exposure to 55fe-labeled ferric siderophore chelates is described. iron is acquired from the ferric chelate of the natural siderophore l-parabactin in a process exhibiting biphastic kinetics by lineweaver-burk analysis. the kinetic data for 1 microm less than [fe l-parabactin] less than 10 microm fit a regression line which suggests a low-affinity system (km = 3.9 +/- 1.2 microm, vmax = 494 pg-at ... | 1990 | 2185228 |
| the cellular location and specificity of bacterial cytochrome c peroxidases. | the locations of cytochrome c peroxidase and catalase activities in the two gram-negative bacteria pseudomonas stutzeri (n.c.i.b. 9721) and paracoccus denitrificans (n.c.i.b. 8944) were investigated by the production of spheroplasts. in both species the cytochrome c peroxidase was predominantly periplasmic: 92% of total activity in ps. stutzeri and 98% of nonmembrane-bound activity in pa. denitrificans were found in this cellular compartment. in contrast, the catalase was mostly in the cytoplasm ... | 1990 | 2173903 |
| cytochrome oxidase assembly in yeast requires the product of cox11, a homolog of the p. denitrificans protein encoded by orf3. | the synthesis of cytochrome oxidase in saccharomyces cerevisiae was recently shown to require a protein encoded by the nuclear gene cox10. this protein was found to be homologous to the putative protein product of the open reading frame orf1 reported in one of the cytochrome oxidase operons of paracoccus denitrificans. in the present study we demonstrate the existence in yeast of a second nuclear gene, cox11, whose encoded protein is homologous to another open reading frame (orf3) present in the ... | 1990 | 2167832 |
| the nitric oxide reductase of paracoccus denitrificans. | the nitric oxide (no) reductase activity of the cytoplasmic membrane of paracoccus denitrificans can be solubilized in dodecyl maltoside with good retention of activity. the solubilized enzyme lacks nadh-dependent activity, but can be assayed with isoascorbate plus 2,3,5,6-tetramethylphenylene-1,4-diamine as electron donor and with horse heart cytochrome c as mediator. reduction of no was measured with an amperomeric electrode. the solubilized enzyme could be separated from other electron-transp ... | 1990 | 2167070 |
| differential reduction in soluble and membrane-bound c-type cytochrome contents in a paracoccus denitrificans mutant partially deficient in 5-aminolevulinate synthase activity. | a mutant of paracoccus denitrificans, dp104, unable to grow anaerobically with nitrate as the terminal electron acceptor or aerobically with methanol as the electron donor and staining negatively in the dimethylphenylene diamine oxidation (nadi) test, was isolated by transposon tn5::phoa mutagenesis. p. denitrificans dp104 grown aerobically with succinate or choline had very low levels (2 to 3% of the wild-type levels) of spectroscopically detectable soluble c-type cytochromes. in contrast, memb ... | 1994 | 7928952 |
| mutagenesis of the gene encoding cytochrome c550 of paracoccus denitrificans and analysis of the resultant physiological effects. | | 1990 | 2160949 |
| secretion of human epidermal growth factor (egf) in autotrophic culture by a recombinant hydrogen-utilizing bacterium, pseudomonas pseudoflava, carrying broad-host-range egf secretion vector pksegf2. | we constructed the broad-host-range human epidermal growth factor (egf) secretion plasmid pksegf2 by inserting the escherichia coli tac promoter, the signal sequence of pseudomonas stutzeri amylase, and the synthesized egf gene into the broad-host-range vector pkt230. e. coli jm109 carrying pksegf2 secreted egf into the periplasm and the culture medium under the control of the tac promoter. pseudomonas aeruginosa pao1161 carrying pksegf2 and pseudomonas putida ac10 carrying pksegf2 secreted egf ... | 1994 | 7944366 |
| mutagenesis of the gene encoding cytochrome c550 of paracoccus denitrificans and analysis of the resultant physiological effects. | by using synthetic oligonucleotides, the gene encoding soluble cytochrome c550 was isolated from a genomic bank of paracoccus denitrificans. the nucleotide sequence of the gene was determined, and the deduced amino acid sequence of the mature protein was found to be similar to the primary structure of purified cytochrome c550 except for the presence of seven additional amino acid residues at the c terminus. at the n terminus of the primary structure was found an additional stretch of 19 amino ac ... | 1990 | 2153663 |
| receptor sites involved in posttranslational transport of apocytochrome c into mitochondria: specificity, affinity, and number of sites. | assembly of cytochrome c involves a series of steps: synthesis of apocytochrome c on free ribosomes, specific binding of apocytochrome c to the mitochondrial surface, transfer across the outer membrane, covalent addition of protoheme, refolding of the polypeptide chain, and association of holocytochrome c with its functional sites at the inner membrane. the binding step of apocytochrome c to neurospora crassa mitochondria was studied by inhibiting the subsequent transfer steps with the heme anal ... | 1983 | 6308663 |
| genetic organization of the mau gene cluster in methylobacterium extorquens am1: complete nucleotide sequence and generation and characteristics of mau mutants. | the nucleotide sequence of the methylamine utilization (mau) gene region from methylobacterium extorquens am1 was determined. open reading frames for 11 genes (maufbedacjglmn) were found, all transcribed in the same orientation. the maub, maua, and mauc genes encode the periplasmic methylamine dehydrogenase (madh) large and small subunit polypeptides and amicyanin, respectively. the products of maud, maug, maul, and maum were also predicted to be periplasmic. the products of mauf, maue, and maun ... | 1994 | 8021187 |
| cytochrome aa3 gene regulation in members of the family rhizobiaceae: comparison of copper and oxygen effects in bradyrhizobium japonicum and rhizobium tropici. | dithionite-reduced minus ferricyanide-oxidized difference spectra on membranes from rhizobium tropici (formerly rhizobium leguminosarum bv. phaseoli) incubated at progressively lower o2 concentrations showed only a slight concomitant decrease in a603, the alpha-peak of cytochrome aa3. in contrast to previous results on bradyrhizobium japonicum, r. tropici showed no significant o2-mediated reduction in the level of either coxa transcription or cytochrome aa3 activity (as measured by ascorbate-n,n ... | 1994 | 8117073 |
| structural features and the reaction mechanism of cytochrome oxidase: iron and copper x-ray absorption fine structure. | x-ray edge absorption of copper and extended fine structure studies of both copper and iron centers have been made of cytochrome oxidase from beef heart, paracoccus dentrificans, and hb-8 thermophilic bacteria (1-2.5 mm in heme). the desired redox state (fully oxidized, reduced co, mixed valence formate and co) in the x-ray beam was controlled by low temperature (-140 degrees c) and was continuously monitored by simultaneous optical spectroscopy and by electron paramagnetic resonance (epr) monit ... | 1981 | 6264990 |
| immunochemical relationship of the major outer membrane protein of rhodopseudomonas sphaeroides 2.4.1 to proteins of other photosynthetic bacteria. | immunoblots of sodium dodecyl sulfate-polyacrylamide gels derived from outer membrane preparations of various strains of rhodopseudomonas sphaeroides revealed polypeptides which cross-reacted with antibody directed against the major outer membrane protein of r. sphaeroides 2.4.1. immunochemical quantitation of the major outer membrane protein of strain 2.4.1 showed approximately 5.5 x 10(4) molecules per cell whether cells were grown chemoheterotrophically or photoheterotrophically. rhodospirill ... | 1983 | 6188744 |
| nitric oxide-dependent proton translocation in various denitrifiers. | respiration of no resulted in transient proton translocation in anaerobically grown cells of four physiologically diverse denitrifiers. paracoccus denitrificans, rhodopseudomonas sphaeroides subsp. denitrificans, "achromobacter cycloclastes," and rhizobium japonicum gave, respectively, h+/no ratios of 3.65, 4.96, 1.94, and 1.12. antimycin a completely inhibited no-dependent proton translocation in p. denitrificans and severely restricted translocation in the r. sphaeroides strain. proton uptake ... | 1985 | 3928599 |
| isolation and characterization of paracoccus denitrificans mutants with defects in the metabolism of one-carbon compounds. | mutants deficient in the metabolism of one-carbon compounds have been obtained by treating paracoccus denitrificans with the mutagen n-methyl-n'-nitro-n-nitrosoguanidine. mutants were selected without enrichment procedures by newly developed plate screening tests. the obtained mutants were characterized by their growth responses, cytochrome composition, enzyme activities, and immunogenic reaction with antisera against methanol dehydrogenase. by these criteria five mutant classes could be disting ... | 1985 | 3905763 |
| cloning and sequencing of the gene coding for the large subunit of methylamine dehydrogenase from thiobacillus versutus. | the gene that codes for the alpha-subunit of methylamine dehydrogenase from thiobacillus versutus, mada, was cloned and sequenced. it codes for a protein of 395 amino acids preceded by a leader sequence of 31 amino acids. the derived amino acid sequence was confirmed by partial amino acid sequencing. the start of the mature protein could not be determined by direct sequencing, since the n terminus appeared to be blocked. instead, it was determined by electrospray mass spectrometry. confirmation ... | 1993 | 8407797 |
| crystal structure analysis of amicyanin and apoamicyanin from paracoccus denitrificans at 2.0 a and 1.8 a resolution. | the crystal structure of amicyanin, a cupredoxin isolated from paracoccus denitrificans, has been determined by molecular replacement. the structure has been refined at 2.0 a resolution using energy-restrained least-squares procedures to a crystallographic residual of 15.7%. the copper-free protein, apoamicyanin, has also been refined to 1.8 a resolution with residual 15.5%. the protein is found to have a beta-sandwich topology with nine beta-strands forming two mixed beta-sheets. the secondary ... | 1993 | 8495197 |
| succinate dehydrogenase in rhodopseudomonas sphaeroides: subunit composition and immunocross-reactivity with other related bacteria. | antibodies were raised against the succinate dehydrogenase (sdh) present in the chromatophores of phototrophically grown rhodopseudomonas sphaeroides. crossed immunoelectrophoresis experiments indicated that the sdh present in the cytoplasmic membranes of heterotrophically grown r. sphaeroides is probably the same enzyme observed in the chromatophores. the enzyme was extracted by triton x-100 in a form which consisted of only two subunits (molecular weight, 68,000 and 30,000) and was not associa ... | 1985 | 3874866 |
| iron-dependent production of a heat-modifiable, 23,000-mr outer membrane protein in paracoccus denitrificans. | production of a 23,000-mr major outer membrane protein of paracoccus denitrificans atcc 13543 was dependent upon the addition of iron to a succinate-salts medium. the 23,000-mr protein was not produced in an iron-deficient medium, but production of five outer membrane proteins in the 85,000- to 72,000-mr range and of catechol were induced. the 23,000-mr protein was not produced in a complex medium even when ferric citrate was added to the medium. production of the protein was influenced by the c ... | 1986 | 3759911 |
| a novel prenyltransferase from paracoccus denitrificans. | a new polyprenyltransferase catalysing the formation of z-double bonds was found and partially purified from extracts of paracoccus denitrificans. the enzyme catalysed a consecutive condensation of isopentenyl diphosphate with ee-farnesyl diphosphate as a primer to produce ee-farnesyl-all-z-hexaprenyl diphosphate (ze-mixed nonaprenyl diphosphate) as the final product. not only ee-farnesyl diphosphate but also neryl diphosphate, ze-farnesyl diphosphate, zee-geranylgeranyl diphosphate and zzee-pen ... | 1986 | 3707524 |
| purification and properties of methylamine dehydrogenase from paracoccus denitrificans. | methylamine dehydrogenase from paracoccus denitrificans was purified to homogeneity in two steps from the periplasmic fraction of methylamine-grown cells. the enzyme exhibited a pi value of 4.3 and was composed of two 46,700-dalton subunits and two 15,500-dalton subunits. each small subunit possessed a covalently bound pyrrolo-quinoline quinone prosthetic group. the amino acid compositions of the large and small subunits are very similar to those of other methylamine dehydrogenases which have be ... | 1987 | 3558322 |
| immunochemical probing of the structure and cofactor of nadh dehydrogenase from paracoccus denitrificans. | monospecific antibody to the respiratory nadh dehydrogenase from paracoccus denitrificans was prepared by using as antigen specific immunoprecipitates containing nadh dehydrogenase which were excised from crossed-immunoelectrophoresis plates. the latter were run with selectively solubilized plasma membranes and antibodies against plasma membranes. the antibody immunoprecipitated nadh dehydrogenase from p. denitrificans membranes biosynthetically labelled with 14c and solubilized with a wide rang ... | 1987 | 3446183 |
| increased outer membrane ornithine-containing lipid and lysozyme penetrability of paracoccus denitrificans grown in a complex medium deficient in divalent cations. | paracoccus denitrificans grown in a complex medium was highly susceptible to lysozyme, in contrast to cells grown in a complex medium supplemented with mg2+ and ca2+ or in a succinate-salts medium. the complex medium was deficient in divalent cations needed for optimum outer membrane stability. the major change in molecular compositions of outer membranes isolated from cells grown under the different conditions was a higher ratio of ornithine-containing lipid to phospholipid in complex-medium-gr ... | 1988 | 3384812 |
| comparison of denitrification by pseudomonas stutzeri, pseudomonas aeruginosa, and paracoccus denitrificans. | a comparison was made of denitrification by pseudomonas stutzeri, pseudomonas aeruginosa, and paracoccus denitrificans. although all three organisms reduced nitrate to dinitrogen gas, they did so at different rates and accumulated different kinds and amounts of intermediates. their rates of anaerobic growth on nitrate varied about 1.5-fold; concomitant gas production varied more than 8-fold. cell yields from nitrate varied threefold. rates of gas production by resting cells incubated with nitrat ... | 1983 | 6407395 |
| s-formylglutathione hydrolase of paracoccus denitrificans is homologous to human esterase d: a universal pathway for formaldehyde detoxification? | downstream of flha, the paracoccus denitrificans gene encoding glutathione-dependent formaldehyde dehydrogenase, an open reading frame was identified and called fgha. the gene product of fgha showed appreciable similarity with human esterase d and with the deduced amino acid sequences of open reading frames found in escherichia coli, haemophilus influenzae, and saccharomyces cerevisiae. mutating fgha strongly reduced s-formylglutathione hydrolase activity. the mutant was unable to grow on methan ... | 1996 | 8892832 |
| nitrogen removal by tubular gel containing nitrosomonas europaea and paracoccus denitrificans. | a new bioreactor for the removal of nitrogen from wastewater is described which consists of a tubular polymeric gel containing nitrosomonas europaea and paracoccus denitrificans. the outer surface of the tube is in aerobic contact with wastewater containing ammonia, while the inside of the tube is in anaerobic contact with ethanol flowing through the tube. n. europaea oxidizes ammonia to nitrite in the gel, and then p. denitrificans reduces the nitrite to nitrogen gas in the same gel. this conce ... | 1996 | 8900015 |
| electron paramagnetic resonance studies of the soluble cua protein from the cytochrome ba3 of thermus thermophilus. | the electron paramagnetic resonance (epr) spectrum of the binuclear cua center in the water-soluble subunit ii fragment from cytochrome ba3 of thermus thermophilus was recorded at 3.93, 9.45, and 34.03 ghz, and the epr parameters were determined by computer simulations. the frequency and m1 dependence of the linewidth was discussed in terms of g strain superimposed on a correlation between the a and g values. the g values were found to be gx = 1.996, gy = 2.011, gz = 2.187, and the two cu ions c ... | 1996 | 8913619 |
| inhibition, but not uncoupling, of respiratory energy coupling of three bacterial species by nitrite. | the effect of nitrite on respiratory energy coupling of three bacteria was studied in light of a recent report that nitrite acted as an uncoupling agent with paracoccus denitrificans grown under denitrifying conditions. our determinations of proton translocation stoichiometry of pseudomonas putida (aerobically grown), pseudomonas aeruginosa, and p. denitrificans (grown both aerobically and under denitrifying conditions) showed nitrite inhibition of proton-to-oxidant stoichiometry, but not uncoup ... | 1980 | 6777373 |
| population analysis in a denitrifying sand filter: conventional and in situ identification of paracoccus spp. in methanol-fed biofilms. | the microbial community of a denitrifying sand filter in a municipal wastewater treatment plant was examined by conventional and molecular techniques to identify the bacteria actively involved in the removal of nitrate. in this system, denitrification is carried out as the last step of water treatment by biofilms growing on quartz grains with methanol as a supplemented carbon source. the biofilms are quite irregular, having a median thickness of 13 to 20 microns. fatty acid analysis of 56 denitr ... | 1996 | 8953706 |
| alterations in the phospholipid composition of rhodopseudomonas sphaeroides and other bacteria induced by tris. | alterations in the phospholipid head group composition of most strains of rhodopseudomonas sphaeroides, as well as rhodopseudomonas capsulata and paracoccus denitrificans, occurred when cells were grown in medium supplemented with tris. growth of r. sphaeroides m29-5 in tris-supplemented medium resulted in the accumulation of n-acylphosphatidylserine (naps) to as much as 40% of the total whole-cell phospholipid, whereas naps represented approximately 28 an 33% of the total phospholipid when r. c ... | 1982 | 6982264 |
| the 5s ribosomal rnas of paracoccus denitrificans and prochloron. | the nucleotide sequences of the 5s rrnas of paracoccus denitrificans and prochloron sp. are (formula: see text), respectively. specific phylogenetic relationships of p. denitrificans with purple non-sulphur bacteria, and of prochloron with cyanobacteria are demonstrated, and unique features of potential secondary structure are described. | 1982 | 7099971 |
| the location of dissimilatory nitrite reductase and the control of dissimilatory nitrate reductase by oxygen in paracoccus denitrificans. | 1. a method is described for preparing spheroplasts from paracoccus denitrificans that are substantially depleted of dissimilatory nitrate reductase (cytochrome cd) activity. treatment of cells with lysozyme + edta together with a mild osmotic shock, followed by centrifugation, yielded a pellet of spheroplasts and a supernatant that contained d-type cytochrome. the spheroplasts were judged to have retained an intact plasma membrane on the basis that less than 1% of the activity of a cytoplasmic ... | 1980 | 7197918 |
| integration of heterologous dna into the genome of paracoccus denitrificans is mediated by a family of is1248-related elements and a second type of integrative recombination event. | all members of the is1248 family residing in the genome of paracoccus denitrificans have been isolated by using a set of insertion sequence entrapment vectors. the family consists of five closely related members that integrate the entrapment vectors at distinct sites. one of these, is1248b, was sequenced and, except for a single base change, shown to be identical to the previously isolated is1248a. southern analysis of genomic dna with labeled is1248 revealed different hybridization patterns for ... | 1995 | 7642505 |
| identification of periplasmic nitrate reductase mo(v) epr signals in intact cells of paracoccus denitrificans. | epr spectroscopy has been successfully used to detect signals due to molybdenum (v) and ferric iron in intact cells of aerobically grown paracoccus denitrificans. the signals are ascribed to the catalytic molybdenum centre and to the haem iron of the periplasmic nitrate reductase. these signals are absent from a mutant strain deficient in this enzyme. the mo(v) signal is due to the high-g split species which has been well characterized in the purified enzyme. this confirms that the high-g split ... | 1995 | 7646461 |
| cloning and characterization of sulfite dehydrogenase, two c-type cytochromes, and a flavoprotein of paracoccus denitrificans gb17: essential role of sulfite dehydrogenase in lithotrophic sulfur oxidation. | a 13-kb genomic region of paracoccus dentrificans gb17 is involved in lithotrophic thiosulfate oxidation. adjacent to the previously reported soxb gene (c. wodara, s. kostka, m. egert, d. p. kelly, and c. g. friedrich, j. bacteriol. 176:6188-6191, 1994), 3.7 kb were sequenced. sequence analysis revealed four additional open reading frames, soxcdef. soxc coded for a 430-amino-acid polypeptide with an mr of 47,339 that included a putative signal peptide of 40 amino acids (mr of 3,599) with a rr mo ... | 1997 | 9260941 |
| replacement of enzyme-bound calcium with strontium alters the kinetic properties of methanol dehydrogenase. | methanol dehydrogenase (medh) possesses tightly bound ca2+ in addition to its pyrroloquinoline quinone (pqq) prosthetic group. ca2+ was replaced with sr2+ by growing the host bacterium, paracoccus denitrificans, in media in which ca2+ was replaced with sr2+. medh, which was purified from these cells (sr-medh), exhibited an increased absorption coefficient for the pqq chromophore, and displayed certain kinetic properties which were different from those of native medh. native medh exhibits an endo ... | 1994 | 8198531 |
| mutants defective in the energy-conserving nadh dehydrogenase of salmonella typhimurium identified by a decrease in energy-dependent proteolysis after carbon starvation. | nadh dehydrogenase is the first component of the respiratory chain. it transfers electrons from nadh to ubiquinone and concomitantly establishes a proton motive force across the membrane. salmonella typhimurium mutants defective in this enzyme were isolated in a screen for strains with increased expression of beta-galactosidase from a hema-lacz protein fusion. this unexpected phenotype results from stabilization of the hybrid protein during carbon starvation and is apparently due to an energy re ... | 1993 | 8234329 |
| cell biology and molecular basis of denitrification. | denitrification is a distinct means of energy conservation, making use of n oxides as terminal electron acceptors for cellular bioenergetics under anaerobic, microaerophilic, and occasionally aerobic conditions. the process is an essential branch of the global n cycle, reversing dinitrogen fixation, and is associated with chemolithotrophic, phototrophic, diazotrophic, or organotrophic metabolism but generally not with obligately anaerobic life. discovered more than a century ago and believed to ... | 1997 | 9409151 |
| isolation and characterization of rhodobacter capsulatus mutants affected in cytochrome cbb3 oxidase activity. | the facultative phototrophic bacterium rhodobacter capsulatus contains only one form of cytochrome (cyt) c oxidase, which has recently been identified as a cbb3-type cyt c oxidase. this is unlike other related species, such as rhodobacter sphaeroides and paracoccus denitrificans, which contain an additional mitochondrial-like aa3-type cyt c oxidase. an extensive search for mutants affected in cyt c oxidase activity in r. capsulatus led to the isolation of at least five classes of mutants. plasmi ... | 1998 | 9473054 |
| genetic analysis of the nuo locus, which encodes the proton-translocating nadh dehydrogenase in escherichia coli. | complex i (ec 1.6.99.3) of the bacterium escherichia coli is considered to be the minimal form of the type i nadh dehydrogenase, the first enzyme complex in the respiratory chain. because of its small size and relative simplicity, the e. coli enzyme has become a model used to identify and characterize the mechanism(s) by which cells regulate the synthesis and assembly of this large respiratory complex. to begin dissecting the processes by which e. coli cells regulate the expression of nuo and th ... | 1998 | 9495756 |
| bacterial community dynamics during start-up of a trickle-bed bioreactor degrading aromatic compounds. | this study was performed with a laboratory-scale fixed-bed bioreactor degrading a mixture of aromatic compounds (solvesso100). the starter culture for the bioreactor was prepared in a fermentor with a wastewater sample of a care painting facility as the inoculum and solvesso100 as the sole carbon source. the bacterial community dynamics in the fermentor and the bioreactor were examined by a conventional isolation procedure and in situ hybridization with fluorescently labeled rrna-targeted oligon ... | 1998 | 9501433 |
| preliminary crystal structure studies of a ternary electron transfer complex between a quinoprotein, a blue copper protein, and a c-type cytochrome. | a ternary electron transfer protein complex has been crystallized and a preliminary structure investigation has been carried out. the complex is composed of a quinoprotein, methylamine dehydrogenase (madh), a blue copper protein, amicyanin, and a c-type cytochrome (c551i). all three proteins were isolated from paracoccus denitrificans. the crystals of the complex are orthorhombic, space group c222(1) with cell dimensions a = 148.81 a, b = 68.85 a, and c = 187.18 a. two types of isomorphous cryst ... | 1993 | 8382992 |
| the active-site cysteines of the periplasmic thioredoxin-like protein ccmg of escherichia coli are important but not essential for cytochrome c maturation in vivo. | a new member of the family of periplasmic protein thiol:disulfide oxidoreductases, ccmg (also called dsbe), was characterized with regard to its role in cytochrome c maturation in escherichia coli. the ccmg protein was shown to be membrane bound, facing the periplasm with its c-terminal, hydrophilic domain. a chromosomal, nonpolar in-frame deletion in ccmg resulted in the complete absence of all c-type cytochromes. replacement of either one or both of the two cysteine residues of the predicted a ... | 1998 | 9537397 |
| buffering capacity and membrane h+ conductance of neutrophilic and alkalophilic gram-positive bacteria. | buffering capacity and membrane h+ conductance were examined in three gram-positive bacteria, staphylococcus aureus, bacillus subtilis, and bacillus alcalophilus. an acid pulse technique was used to measure both parameters. the buffering capacity and membrane h+ conductance of b. alcalophilus are influenced by the ph of the medium and the culture conditions. suspensions of b. alcalophilus cells from both h. a. medium and l-malate medium cultures grown at ph 10.5 exhibited higher values for these ... | 1998 | 9546171 |
| oxygen regulation of the ccon gene encoding a component of the cbb3 oxidase in rhodobacter sphaeroides 2.4.1t: involvement of the fnrl protein. | the cconoqp gene cluster of rhodobacter sphaeroides 2.4.1t encodes a cbb3 cytochrome oxidase which is utilized in oxygen-limited conditions for aerobic respiration. the beta-galactosidase activity of a ccon::lacz transcriptional fusion was low under high (30%)-oxygen and anaerobic growth conditions. maximal ccon::lacz expression was observed when the oxygen concentration was lowered to 2%. in an fnrl mutant, ccon::lacz expression was significantly lower than in the wild-type strain, suggesting t ... | 1998 | 9555909 |
| transmembrane heme delivery systems. | heme proteins play pivotal roles in a wealth of biological processes. despite this, the molecular mechanisms by which heme traverses bilayer membranes for use in biosynthetic reactions are unknown. the biosynthesis of c-type cytochromes requires that heme is transported to the bacterial periplasm or mitochondrial intermembrane space where it is covalently ligated to two reduced cysteinyl residues of the apocytochrome. results herein suggest that a family of integral membrane proteins in prokaryo ... | 1998 | 9560218 |
| control of photosystem formation in rhodobacter sphaeroides. | | 1998 | 9603864 |
| characterization of the hcnabc gene cluster encoding hydrogen cyanide synthase and anaerobic regulation by anr in the strictly aerobic biocontrol agent pseudomonas fluorescens cha0. | the secondary metabolite hydrogen cyanide (hcn) is produced by pseudomonas fluorescens from glycine, essentially under microaerophilic conditions. the genetic basis of hcn synthesis in p. fluorescens cha0 was investigated. the contiguous structural genes hcnabc encoding hcn synthase were expressed from the t7 promoter in escherichia coli, resulting in hcn production in this bacterium. analysis of the nucleotide sequence of the hcnabc genes showed that each hcn synthase subunit was similar to kno ... | 1998 | 9620970 |
| spectroscopic characterization of cytochrome c peroxidase from paracoccus denitrificans. | the cytochrome c peroxidase of paracoccus denitrificans is similar to the well-studied enzyme from pseudomonas aeruginosa. like the pseudomonas enzyme, the paracoccus peroxidase contains two haem c groups, one high potential and one low potential. the high-potential haem acts as a source of the second electron for h2o2 reduction, and the low-potential haem acts as a peroxidatic centre. reduction with ascorbate of the high-potential haem of the paracoccus enzyme results in a switch of the low-pot ... | 1993 | 8397509 |
| crystallization and preliminary x-ray analysis of electron transfer flavoproteins from human and paracoccus denitrificans. | mammalian electron transfer flavoprotein (etf) is a soluble, heterodimeric flavoprotein responsible for the oxidation of at least nine primary matrix flavoprotein dehydrogenases. crystals have been obtained for the recombinant human electron transfer flavoprotein (etfhum) by the sitting-drop vapor diffusion technique using polyethylene glycol (peg) 1500 at ph 7.0 as the precipitating agent. etfhum crystallizes in the monoclinic space group p2(1), with unit cell parameters a = 47.46 angstrum, b = ... | 1995 | 8520493 |
| molecular analysis of the poly(3-hydroxyalkanoate) synthase gene from a methylotrophic bacterium, paracoccus denitrificans. | a 3.6-kb ecori-sali fragment of paracoccus denitrificans dna hybridized with a dna probe carrying the poly(3-hydroxyalkanoate) (pha) synthase gene (phac) of alcaligenes eutrophus. nucleotide sequence analysis of this region showed the presence of a 1,872-bp open reading frame (orf), which corresponded to a polypeptide with a molecular weight of 69,537. upstream of the orf, a promoter-like sequence was found. escherichia coli carrying the fusion gene between lacz and the orf accumulated a level o ... | 1996 | 8550512 |
| cua and cuz are variants of the electron transfer center in nitrous oxide reductase. | nitrous oxide reductase (n2or) is a dimeric copper-dependent bacterial enzyme that catalyzes the reduction of n2o to n2 as part of the denitrification pathway. in the absence of an x-ray crystal structure, the current model of the nature of the copper sites within the enzyme is based on four copper atoms per monomer and assigns two copper atoms to an electron transfer center, cua, a bis-thiolate-bridged dinuclear copper center found to date only in n2or and cytochrome c oxidase, and two copper a ... | 1998 | 9707571 |
| thermodynamics of electron transfer in escherichia coli cytochrome bo3. | the proton translocation mechanism of the escherichia coli cytochrome bo3 complex is intimately tied to the electron transfers within the enzyme. herein we evaluate two models of proton translocation in this enzyme, a cytochrome c oxidase-type ion-pump and a q-cycle mechanism, on the basis of the thermodynamics of electron transfer. we conclude that from a thermodynamic standpoint, a q-cycle is the more favorable mechanism for proton translocation and is likely occurring in the enzyme. | 1998 | 9751719 |
| c-type cytochromes and manganese oxidation in pseudomonas putida mnb1. | pseudomonas putida mnb1 is an isolate from an mn oxide-encrusted pipeline that can oxidize mn(ii) to mn oxides. we used transposon mutagenesis to construct mutants of strain mnb1 that are unable to oxidize manganese, and we characterized some of these mutants. the mutants were divided into three groups: mutants defective in the biogenesis of c-type cytochromes, mutants defective in genes that encode key enzymes of the tricarboxylic acid cycle, and mutants defective in the biosynthesis of tryptop ... | 1998 | 9758766 |
| the cytochrome c maturation operon is involved in manganese oxidation in pseudomonas putida gb-1. | a pseudomonas putida strain, strain gb-1, oxidizes mn2+ to mn oxide in the early stationary growth phase. it also secretes a siderophore (identified as pyoverdine) when it is subjected to iron limitation. after transposon (tn5) mutagenesis several classes of mutants with differences in mn2+ oxidation and/or secretion of the mn2+-oxidizing activity were identified. preliminary analysis of the tn5 insertion site in one of the nonoxidizing mutants suggested that a multicopper oxidase-related enzyme ... | 1998 | 9758767 |
| development of pcr primer systems for amplification of nitrite reductase genes (nirk and nirs) to detect denitrifying bacteria in environmental samples. | a system was developed for the detection of denitrifying bacteria by the amplification of specific nitrite reductase gene fragments with pcr. primer sequences were found for the amplification of fragments from both nitrite reductase genes (nirk and nirs) after comparative sequence analysis. whenever amplification was tried with these primers, the known nir type of denitrifying laboratory cultures could be confirmed. likewise, the method allowed a determination of the nir type of five laboratory ... | 1998 | 9758798 |
| the mechanism of proton pumping by cytochrome c oxidasex127e comments]. | cytochrome c oxidase catalyzes the reduction of oxygen to water that is accompanied by pumping of four protons across the mitochondrial or bacterial membrane. triggered by the results of recent x-ray crystallographic analyses, published data concerning the coupling of individual electron transfer steps to proton pumping are reanalyzed: conversion of the conventional oxoferryl intermediate f to the fully oxidized form o is connected to pumping of only one proton. most likely one proton is already ... | 1998 | 9788998 |
| a cytochrome cbb3 (cytochrome c) terminal oxidase in azospirillum brasilense sp7 supports microaerobic growth. | spectral analysis indicated the presence of a cytochrome cbb3 oxidase under microaerobic conditions in azospirillum brasilense sp7 cells. the corresponding genes (cytnoqp) were isolated by using pcr. these genes are organized in an operon, preceded by a putative anaerobox. the phenotype of an a. brasilense cytn mutant was analyzed. under aerobic conditions, the specific growth rate during exponential phase (mu(e)) of the a. brasilense cytn mutant was comparable to the wild-type specific growth r ... | 1998 | 9791120 |
| methanotrophs and methanogens in masonry | methanotrophs were present in 48 of 225 stone samples which were removed from 19 historical buildings in germany and italy. the average cell number of methanotrophs was 20 cfu per g of stone, and their activities ranged between 11 and 42 pmol of ch4 g of stone-1 day-1. twelve strains of methane-oxidizing bacteria were isolated. they belonged to the type ii methanotrophs of the genera methylocystis, methylosinus, and methylobacterium. in masonry, growth substrates like methane or methanol are ava ... | 1998 | 9797318 |
| construction and characterization of an azurin analog for the purple copper site in cytochrome c oxidase. | a protein analog of a purple copper center has been constructed from a recombinant blue copper protein (pseudomonas aeruginosa azurin) by replacing the loop containing the three ligands to the blue copper center with the corresponding loop of the cua center in cytochrome c oxidase (cox) from paracoccus denitrificans. the electronic absorption in the uv and visible region (uv-vis) and electron paramagnetic resonance (epr) spectra of this analog are remarkably similar to those of the native cua ce ... | 1996 | 8552661 |
| a new approach to utilize pcr-single-strand-conformation polymorphism for 16s rrna gene-based microbial community analysis. | single-strand-conformation polymorphism (sscp) of dna, a method widely used in mutation analysis, was adapted to the analysis and differentiation of cultivated pure-culture soil microorganisms and noncultivated rhizosphere microbial communities. a fragment (approximately 400 bp) of the bacterial 16s rrna gene (v-4 and v-5 regions) was amplified by pcr with universal primers, with one primer phosphorylated at the 5' end. the phosphorylated strands of the pcr products were selectively digested wit ... | 1998 | 9835576 |
| cloning of the alcaligenes latus polyhydroxyalkanoate biosynthesis genes and use of these genes for enhanced production of poly(3-hydroxybutyrate) in escherichia coli. | polyhydroxyalkanoates (phas) are microbial polyesters that can be used as completely biodegradable polymers, but the high production cost prevents their use in a wide range of applications. recombinant escherichia coli strains harboring the ralstonia eutropha pha biosynthesis genes have been reported to have several advantages as pha producers compared with wild-type pha-producing bacteria. however, the pha productivity (amount of pha produced per unit volume per unit time) obtained with these r ... | 1998 | 9835580 |
| molecular genetics of the genus paracoccus: metabolically versatile bacteria with bioenergetic flexibility. | paracoccus denitrificans and its near relative paracoccus versutus (formerly known as thiobacilllus versutus) have been attracting increasing attention because the aerobic respiratory system of p. denitrificans has long been regarded as a model for that of the mitochondrion, with which there are many components (e.g., cytochrome aa3 oxidase) in common. members of the genus exhibit a great range of metabolic flexibility, particularly with respect to processes involving respiration. prominent exam ... | 1998 | 9841665 |
| cytochrome cb-type nitric oxide reductase with cytochrome c oxidase activity from paracoccus denitrificans atcc 35512. | a highly active nitric oxide reductase was purified from paracoccus denitrificans atcc 35512, formerly named thiosphaera pantotropha, which was anaerobically cultivated in the presence of nitrate. the enzyme was composed of two subunits with molecular masses of 34 and 15 kda and contained two hemes b and one heme c per molecule. copper was not found in the enzyme. the spectral properties suggested that one of the two hemes b and heme c were in six-coordinated low-spin states and another heme b w ... | 1996 | 8606159 |
| proton exit from the heme-copper oxidase of escherichia coli. | pathways of proton entry have been identified in the proton-translocating heme-copper oxidases, but the proton exit pathway is unknown. here we report experiments with cytochrome bo3 in escherichia coli cells that may identify the beginning of the exit pathway. systematic mutations of arginines 438 and 439 (r481 and r482 in the e. coli enzyme), numbering as in cytochrome aa3 from bovine heart mitochondria, which interact with the ring d propionates of the two heme groups, reveal that the d propi ... | 1999 | 9874767 |
| subunit ii of bacillus subtilis cytochrome c oxidase is a lipoprotein. | the sequence of the n-terminal end of the deduced ctac gene product of bacillus species has the features of a bacterial lipoprotein. ctac is the subunit ii of cytochrome caa3, which is a cytochrome c oxidase. using bacillus subtilis mutants blocked in lipoprotein synthesis, we show that ctac is a lipoprotein and that synthesis of the membrane-bound protein and covalent binding of heme to the cytochrome c domain is not dependent on processing at the n-terminal part of the protein. mutants blocked ... | 1999 | 9882689 |
| the rhodobacter sphaeroides 2.4.1 rho gene: expression and genetic analysis of structure and function. | the gene which encodes transcription termination factor rho from rhodobacter sphaeroides 2.4.1, the gram-negative facultative photosynthetic bacterium, has been cloned and sequenced. the deduced protein shows a high level of sequence similarity to other bacterial rho factors, especially those from proteobacteria. however, several amino acid substitutions in the conserved atp-binding site have been identified. when expressed in escherichia coli, the r. sphaeroides rho gene relieves rho-dependent ... | 1996 | 8606169 |
| high-molecular-mass multi-c-heme cytochromes from methylococcus capsulatus bath. | the polypeptide and structural gene for a high-molecular-mass c-type cytochrome, cytochrome c553o, was isolated from the methanotroph methylococcus capsulatus bath. cytochrome c553o is a homodimer with a subunit molecular mass of 124,350 da and an isoelectric point of 6. 0. the heme c concentration was estimated to be 8.2 +/- 0.4 mol of heme c per subunit. the electron paramagnetic resonance spectrum showed the presence of multiple low spin, s = 1/2, hemes. a degenerate oligonucleotide probe syn ... | 1999 | 9922265 |
| sporadic distribution of trna(arg)ccu introns among alpha-purple bacteria: evidence for horizontal transmission and transposition of a group i intron. | a group i intron interrupts the trna(arg)ccu gene of the alpha-purple bacterium agrobacterium tumefaciens (b. reinhold-hurek and d. a. shub, nature [london] 357:173-176, 1992). in this study, we assess the distribution of the corresponding intron among 12 additional species of alpha-purple bacteria. of 10 newly identified trna(arg)ccu genes, we found only two that contained an intron homologous to that of the agrobacterium intron. this restricted and scattered distribution of the trna(arg)ccug i ... | 1999 | 9922276 |