| omegon-km: a transposable element designed for in vivo insertional mutagenesis and cloning of genes in gram-negative bacteria. | to combine the features of the omega interposons with the advantages of in vivo transposition mutagenesis, we have constructed an artificial transposon, called omegon-km. the omegon-km transposon is carried on the plasmid pjff350 which can be conjugally mobilized into a broad range of gram-negative bacteria. omegon-km is flanked, in inverted orientation, by synthetic 28-bp repeats derived from the ends of is1. in addition, each end of omegon-km has the very efficient transcription and translatio ... | 1989 | 2546859 |
| the reactions of the oxidase and reductases of paracoccus denitrificans with cytochromes c. | electron transport in the paracoccus denitrificans respiratory chain system is considerably more rapid when it includes the membrane-bound cytochrome c552 than with either soluble paracoccus c550 or bovine cytochrome c; a pool function for cytochrome c is not necessary. low concentrations of paracoccus or bovine cytochrome c stimulate the oxidase activity. this observation could explain the multiphasic scatchard plots which are obtained. a negatively charged area on the "back side" of paracoccus ... | 1991 | 1646799 |
| redox protein electron-transfer mechanisms: electrostatic interactions as a determinant of reaction site in c-type cytochromes. | the effect of ionic strength on the rate constant for electron transfer has been used to determine the magnitude and charge sign of the net electrostatic potential which exists in close proximity to the sites of electron transfer on various c-type cytochromes. the negatively charged ferricyanide ion preferentially reacts at the positively charged exposed heme edge region on the front side of horse cytochrome c and paracoccus cytochrome c2. in contrast, at low ionic strength, the positively charg ... | 1989 | 2551370 |
| evolutionary aspects of cytochrome c oxidase. | the presence of additional subunits in cytochrome oxidase distinguish the multicellular eukaryotic enzyme from that of a simple unicellular bacterial enzyme. the number of these additional subunits increases with increasing evolutionary stage of the organism. subunits i-iii of the eukaryotic enzyme are related to the three bacterial subunits, and they are encoded on mitochondrial dna. the additional subunits are nuclear encoded. experimental evidences are presented here to indicate that the lowe ... | 1991 | 1646800 |
| transposable elements for efficient manipulation of a wide range of gram-negative bacteria: promoter probes and vectors for foreign genes. | we describe here the construction and use of a series of modified transposons based on the insertion sequence is1. like their parent, omegon-km [fellay et al., gene 76 (1989) 215-226], these elements permit efficient insertional mutagenesis of a variety of gram-negative bacteria. the presence of a functional pbr322 origin of replication within the transposable element facilitates subsequent cloning of the mutated gene. the omegon-km system was previously shown to function in pseudomonas putida, ... | 1989 | 2559879 |
| quantitative selection of denitrifying bacteria in continuous cultures and requirement for organic carbon. i. starch. | a mixed population of bacteria from bottom sludge of nitrogen wastewater reservoir was incubated in continuous culture in medium containing 1000 mg nitrate nitrogen/l and starch. maximal efficiency of denitrification was 5 mg n/l/h. marked changes in participation of denitrifying bacteria (16-76%) among total number of bacteria was observed, this being dependent on the ratio of starch concentration (cs) to nitrogen concentration (cn) in the medium. the optimal cs/cn ratio ensuring highest partic ... | 1985 | 2579531 |
| assimilation of methylamine by paracoccus denitrificans involves formaldehyde transport by a specific carrier. | assimilation of methylamine by paracoccus denitrificans involves the following enzymes: a periplasmic methylamine dehydrogenase, a formaldehyde transport system, cytoplasmic formaldehyde and formate dehydrogenase. formaldehyde transport follows saturation kinetics with a high substrate affinity (km = 7 microm), and is severely inhibited by iodoacetate, cyanide and p-trifluoromethoxy carbonylcyanide phenylhydrazone. expression of the formaldehyde carrier is regulated by the carbon source. | 1989 | 2612879 |
| formate dependent nitrate and nitrite reduction to ammonia by citrobacter freundii and competition with denitrifying bacteria. | citrobacter freundii, paracoccus denitrificans and pseudomonas stutzeri were grown either singly or in mixed culture in anaerobic nitrate or nitrite limited chemostats with formate and/or succinate as electron donors and carbon sources. c. freundii reduced nitrate or nitrite stoichiometrically to ammonia. maximum molar growth yields for nitrate (nitrite) were 15.3 (9.9) g/mol for c. freundii on formate with succinate as carbon source, 15.3 (9.5) g/mol for ps. stutzeri on succinate and 32.3 (20.4 ... | 1989 | 2619287 |
| structure, control and assembly of a bacterial electron transport system as exemplified by paracoccus denitrificans. | | 1989 | 2697623 |
| subunit iii of cytochrome c oxidase is not involved in proton translocation: a site-directed mutagenesis study. | subunit iii (coiii) is one of the three core subunits of the aa3-type cytochrome c oxidase. coiii does not contain any of the redox centres and can be removed from the purified enzyme but has a function during biosynthesis of the enzyme. dicyclohexyl carbodiimide (dccd) modifies a conserved glutamic acid residue in coiii and abolishes the proton translocation activity of the enzyme. in this study, the invariant carboxylic acids e98 (the dccd-binding glutamic acid) and d259 of coiii were changed ... | 1991 | 1648477 |
| 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 |
| 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 |
| some characteristics of a chromophoric lipid associated with nitric oxide reductase from paracoccus denitrificans. | a lipid with a uv chromophore (lambda max = 274 nm) was purified in small amounts from nitric oxide reductase of paracoccus denitrificans and determined to have a molecular weight of 686, a most probable formula of c43h78o4n2 and about two phenylhydrazine-reactive carbonyls. on the basis of 1h and 13c-nmr, ir and mass spectrometric studies, the chromophoric lipid was inferred to have something like bilateral symmetry and to contain ketone-like carbonyls, alkene centers and at least three alkyl o ... | 1989 | 2803506 |
| molecular cloning of the l-phenylalanine transaminase gene from paracoccus denitrificans in escherichia coli k-12. | the l-phenylalanine transaminase gene of paracoccus denitrificans was cloned by a shotgun method using the escherichia coli k-12 mutant dg30, which lacks three distinct transaminase genes. plasmid ppap142 was constructed by inserting a 2.2-kb fragment carrying the transaminase gene into puc18. strain e. coli k-12 hb101 cells harboring the plasmid produced 20-fold to 30-fold more transaminase than wild type p. denitrificans cells. the nucleotide sequence of the 2.2-kb fragment was determined, rev ... | 1991 | 2054101 |
| the genes of the paracoccus denitrificans bc1 complex. nucleotide sequence and homologies between bacterial and mitochondrial subunits. | the genes for the three subunits of the cytochrome bc1 complex from the bacterium paracoccus denitrificans were identified by screening a gene library constructed in pbr 322 for expression using a cytochrome c1-specific antibody. these three genes coding for the fes subunit, cytochrome b, and cytochrome c1 were located on contiguous sites on the genome in a presumed operon arrangement. the dna-deduced amino acid sequence shows that all three subunits are homologous to corresponding polypeptides ... | 1987 | 2820981 |
| identification of the nadh-binding subunit of nadh-ubiquinone oxidoreductase of paracoccus denitrificans. | the nadh dehydrogenase complex isolated from paracoccus denitrificans is composed of approximately 10 unlike polypeptides and contains noncovalently bound fmn, non-heme iron, and acid-labile sulfide [yagi, t. (1986) arch. biochem. biophys. 250, 302-311]. when the paracoccus nadh dehydrogenase complex was irradiated by uv light in the presence of [adenylate-32p]nad, radioactivity was incorporated exclusively into one of three polypeptides of mr approximately 50,000. similar results were obtained ... | 1990 | 2117469 |
| immunological and spectral characterization of partly purified cytochrome oxidase from the cyanobacterium synechocystis 6714. | membranes were isolated by french pressure cell extrusion of lysozyme-preincubated cells of the cyanobacterium synechocystis 6714 after growth in the presence of 0.4 m nacl for 4 days. these cells showed up to 6-fold respiratory activity (oxygen uptake) when compared to control cells. separation of plasma and thylakoid membranes revealed that the major part of cytochrome c oxidase was associated with the latter. immunoblotting of sodium dodecylsulfate polyacrylamide gel electrophorized membranes ... | 1987 | 2825695 |
| amino acid sequences of cytochrome c-554(548) and cytochrome c' from a halophilic denitrifying bacterium of the genus paracoccus. | the amino acid sequences of the cytochromes c-554(548) and c' from the moderately halophilic bacterium paracoccus sp., i.a.m. 203 (= a.t.c.c. 12084, n.c.i.b. 8669) have been determined. cytochrome c-554(548) consists of a single polypeptide chain of 83 residues, and dimerizes strongly. the most similar protein of known sequence is the n-terminal half of the dihaem cytochrome c4, and other related proteins include the cytochrome c-554(547) of thiobacillus neapolitanus and the cytochrome c-553 of ... | 1987 | 2829828 |
| resonance raman spectroscopy of amicyanin, a blue copper protein from paracoccus denitrificans. | the copper binding site of amicyanin from paracoccus denitrificans has been examined by resonance raman spectroscopy. the pattern of vibrational modes is clearly similar to those of the blue copper proteins azurin and plastocyanin. intense resonance-enhanced peaks are observed at 377, 392, and 430 cm-1 as well as weaker overtones and combination bands in the high frequency region. most of the peaks below 500 cm-1 shift 0.5-1.5 cm-1 to lower energy when the protein is exposed to d2o. based on the ... | 1988 | 2830281 |
| electrophoretically monodisperse cytochrome c oxidases. | a discontinuous gradient polyacrylamide gel electrophoresis under nondenaturing conditions has been used to demonstrate monodispersity of procaryotic and eucaryotic cytochrome c oxidase preparations. alkaline treated bovine enzyme which contains nine subunits as analysed by subsequent discontinuous sds-polyacrylamide gel electrophoresis is a monodisperse dimer in 0.1% triton x-100 and a monomer in 0.1% dodecyl maltoside. the mr-values corrected for bound detergent are 286,000 in triton x-100 and ... | 1988 | 2831897 |
| radiorespirometry evidence for the discrimination between 13c-enriched glucose and unlabelled glucose molecules by paracoccus denitrificans. | paracoccus denitrificans was grown on either unlabelled glucose, [1-13c]glucose or [6-13c]glucose as the sole carbon source for growth. the cells were then incubated with a range of 14c-glucose substrates to compare the 14co2-evolution rates between cells grown on the glucose and the 13c-labelled glucose. cells grown on 13c-glucose had significantly faster rates of 14co2-evolution than those grown on unlabelled glucose. the % yields of 14co2, per [1-14c]-, [6-14c]- and [u-14c]glucose supplied we ... | 1990 | 2117553 |
| mutagenesis of the gene encoding cytochrome c550 of paracoccus denitrificans and analysis of the resultant physiological effects. | | 1990 | 2160949 |
| the sequence of the cyo operon indicates substantial structural similarities between the cytochrome o ubiquinol oxidase of escherichia coli and the aa3-type family of cytochrome c oxidases. | the cytochrome o complex is one of two ubiquinol oxidases in the aerobic respiratory system of escherichia coli. this enzyme catalyzes the two-electron oxidation of ubiquinol-8 which is located in the cytoplasmic membrane, and the four-electron reduction of molecular oxygen to water. the purified oxidase contains at least four subunits by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and has been shown to couple electron flux to the generation of a proton motive force across ... | 1990 | 2162835 |
| 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 |
| both hemes are located in subunit one of paracoccus denitrificans cytochrome c oxidase. | | 1988 | 2841679 |
| bacterial cytochrome c oxidases: cloning and sequence determination of subunit ii of the paracoccus oxidase. | | 1988 | 2841680 |
| cox10 codes for a protein homologous to the orf1 product of paracoccus denitrificans and is required for the synthesis of yeast cytochrome oxidase. | respiratory-defective mutants of saccharomyces cerevisiae assigned to pet complementation group g19 lack cytochrome oxidase activity and cytochromes a and a3. the enzyme deficiency is caused by recessive mutations in the nuclear gene cox10. analyses of cytochrome oxidase subunits suggest that the product of cox10 provides an essential function at a posttranslational stage of enzyme assembly. the wild type cox10 gene has been cloned by transformation of a mutant from complementation group g19 wit ... | 1990 | 2167310 |
| 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 |
| subunit iii of cytochrome c oxidase is expressed in paracoccus denitrificans. | polyclonal antibodies have been obtained against a synthetic dodecapeptide identical to the aminoacid sequence 120-131 dspikdgvwppe (inferred from its dna sequence) of paracoccus denitrificans cytochrome c oxidase subunit iii. the antibodies had a titer higher than 1:10000 when tested against the antigen. these antibodies have been used to produce immunological evidence that, despite the fact that subunit iii is not isolated with cytochrome c oxidase, it exists in paracoccus denitrificans lysate ... | 1988 | 2841930 |
| kinetics of oxidative phosphorylation in paracoccus denitrificans. 1. mechanism of atp synthesis at the active site(s) of f0f1-atpase. | (1) the rate of atp synthesis during nadh-driven aerobic respiration has been measured in plasma membrane vesicles from paracoccus denitrificans as a function of the concentration of the substrates, adp and inorganic phosphate (pi). in both cases, the response of the reaction to changes in the degree of saturation of the f0f1-atpase generated a perfect micaelian dependence which allowed the determination of the corresponding michaelis constants, kmadp and kmpi. (2) these kinetic parameters posse ... | 1990 | 2148690 |
| 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 |
| kinetics of oxidative phosphorylation in paracoccus denitrificans. 2. evidence for a kinetic and thermodynamic modulation of f0f1-atpase by the activity of the respiratory chain. | (1) the affinity of the f0f1-atpase from paracoccus denitrificans for atp during nadh-driven oxidative phosphorylation has been analyzed under different conditions by examining the type and extent of product inhibition. (2) a limited collapse of the protonmotive force (delta p) due to partial uncoupling does not increase the affinity for atp at the active site(s) of the enzyme; instead, a partial noncompetitive inhibition becomes apparent, compatible with the binding of atp to a noncatalytic sit ... | 1990 | 2148691 |
| 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 |
| 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 |
| subunit i is the catalytic center of paracoccus denitrificans cytochrome c oxidase. | | 1988 | 2854385 |
| are there isoenzymes of cytochrome c oxidase in paracoccus denitrificans? | we have used a gene replacement strategy to delete the previously isolated gene [(1987) embo j. 6, 2825-2833] for the cytochrome c oxidase subunit i from paracoccus denitrificans. the resulting mutant was still able to synthesize active cytochrome c oxidase. this led us to look for another locus which could completely suppress the mutation. in this study we report the isolation of a second gene encoding subunit i. an open reading frame coding for cytochrome c 550 was found upstream from this gen ... | 1990 | 2155830 |
| formation of a potent respiratory inhibitor at nitrite reduction by nitrite reductase isolated from the bacterium paracoccus denitrificans. | a new method of dissimilatory nitrite reductase (cytochrome cd1) isolation from the periplasmic fraction of anaerobically grown cells of the bacterium paracoccus denitrificans was developed, using ionex and gel permeation chromatography with fplc system (pharmacia, sweden). in experiments with isolated enzyme it was shown that through a nitrite reduction, catalysed by this enzyme, a substance (presumably nitric oxide) was formed which at submicromolar concentrations inhibited terminal cytochrome ... | 1990 | 2266492 |
| hydroxylamine as an inhibitor and terminal acceptor in the respiratory chain of the bacterium paracoccus denitrificans. | three sites of inhibitory action of hydroxylamine were identified in the respiratory chain of anaerobically grown bacterium paracoccus denitrificans. terminal oxidases were blocked at concentrations of 10(-4) to 10(-3) mol.l-1, and the inhibitor competed with artificial donor of electrons n, n, n', n'-tetramethyl-l, 4-phenylenediamine. in the anaerobic part of the respiratory chain inhibition of nitrite reductase and apparently also nitric oxide reductase occurred, resulting in the increased acc ... | 1990 | 2269422 |
| the kinetic and isotopic competence of nitric oxide as an intermediate in denitrification. | rates of no uptake by five denitrifying bacteria were estimated by no-electrode and gas chromatography methods under conditions of rather low cell densities and [noaq]. the rates so measured, vmaxno, represent lower limits for the true value of that parameter, but nevertheless exceed vmax for nitrite uptake, vmaxni, by a factor of two typically. previous estimates under suboptimal conditions had placed vmaxno at 0.3-0.5 of vmaxni (st. john, r. t., and hollocher, t. c. (1977) j. biol. chem. 252, ... | 1990 | 2295624 |
| inhibition by trimethylamine of methylamine oxidation by paracoccus denitrificans and bacterium w3a1. | trimethylamine, a common substrate for methylotrophic growth, specifically inhibited methylamine-dependent respiration by paracoccus denitrificans and bacterium w3a1. these effects were caused by the specific inhibition by trimethylamine of the periplasmic quinoprotein methylamine dehydrogenase. steady-state kinetic analysis of the effect of trimethylamine on methylamine oxidation by methylamine dehydrogenase indicated that the inhibition was a mixed type. apparent ki values for trimethylamine o ... | 1990 | 2331476 |
| spectral and electrochemical properties of glutaryl-coa dehydrogenase from paracoccus denitrificans. | studies of the spectral (uv/vis and resonance raman) and electrochemical properties of the fad-containing enzyme glutaryl-coa dehydrogenase (gcd) from paracoccus denitrificans reveal that the properties of the oxidized enzyme (gcdox) appear to be invariant from those properties known for other acyl-coa dehydrogenases such as mammalian general acyl-coa dehydrogenase (gacd) and butyryl-coa dehydrogenase (bcd) from megasphaera elsdenii. however, when either free or complexed gcd is reduced, its spe ... | 1990 | 2340266 |
| cytochrome c-550 mediates electron transfer from inducible periplasmic c-type cytochromes to the cytoplasmic membrane of paracoccus denitrificans. | electron transfer from periplasmic cytochromes c to the membrane-bound respiratory chain has been studied with the isolated cytochromes and membrane preparations from paracoccus denitrificans. when reduced cytochromes were incubated with spheroplasts only the constitutive cytochrome c-550 was rapidly oxidized. the inducible cytochromes c-551i and c-553i were not oxidized at appreciable rates. cytochrome c-550 was able to mediate the transfer of electrons from either cytochrome c-551i or cytochro ... | 1989 | 2538362 |
| characterisation of phosphate binding to mitochondrial and bacterial membrane-bound atp synthase by studies of inhibition with 4-chloro-7-nitrobenzofurazan. | the effect of phosphate on the inhibition by 4-chloro-7-nitrobenzofurazan of the atpase activity of the proton-translocating atp synthase in heart submitochondrial particles was investigated. binding of phosphate protected strongly against the inhibition. a dissociation constant of 0.2 mm was determined for the enzyme x pi complex and shown to be independent of ph in the range 7.0-8.0. the protective effect of phosphate was mimicked by arsenate but not by sulphate or malonate. similar results we ... | 1986 | 2869972 |
| oxidation of cytochrome c by cytochrome c oxidase: spectroscopic binding studies and steady-state kinetics support a conformational transition mechanism. | the long-known biphasic response of cytochrome c oxidase to the concentration of cytochrome c has been explained, alternatively, by the presence of a catalytic and a regulatory site on the oxidase, by negative cooperativity between adjacent active sites in dimeric oxidase, or by a transition of the enzyme molecule between different conformational states. the three mechanistic hypotheses allow testable predictions about the relationship between substrate binding and steady-state kinetics catalyze ... | 1989 | 2539857 |
| 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 |
| growth of paracoccus denitrificans on [2,3-13c]succinate and [1,4-13c]succinate. iii. biosynthetic pathways. | the biosynthesis in vivo of a number of amino acids, sugars, and purines in paracoccus denitrificans grown on either [2,3-13c]succinate or [1,4-13c]succinate was investigated by using gas chromatography-mass spectrometry. the distribution of label in the tca-cycle-related amino acids indicated that carbon intermediates of energy metabolism were utilized as precursors for the biosynthesis of these amino acids in vivo. the biosynthesis of glycine, serine, phenylalanine and glycerol from labelled s ... | 1988 | 2895930 |
| the energy-conserving nitric-oxide-reductase system in paracoccus denitrificans. distinction from the nitrite reductase that catalyses synthesis of nitric oxide and evidence from trapping experiments for nitric oxide as a free intermediate during denitrification. | 1. a clark-type electrode that responds to nitric oxide has been used to show that cytoplasmic membrane vesicles of paracoccus denitrificans have a nitric-oxide reductase activity. nitrous oxide is the reaction product. nadh, succinate or isoascorbate plus 2,3,5,6-tetramethyl-1,4-phenylene diamine can act as reductants. the nadh-dependent activity is resistant to freezing of the vesicles and thus the nadh:nitric-oxide oxidoreductase activity of stored frozen vesicles provides a method for calibr ... | 1989 | 2920732 |
| methanol dissimilation in xanthobacter h4-14: activities, induction and comparison to pseudomonas am1 and paracoccus denitrificans. | methanol dissimilatory enzymes detected in the methanol autotroph xanthobacter h4-14 were a typical phenazine methosulphate-linked methanol dehydrogenase, a nad+-linked formate dehydrogenase, and a dye-linked formaldehyde dehydrogenase that could be assayed only by activity stains of polyacrylamide gels. this same methanol dehydrogenase activity was found in ethanol-grown cells and was apparently utilized for ethanol oxidation. formaldehyde dehydrogenase activities were investigated in paracoccu ... | 1985 | 2933486 |
| a comparative study of the resonance raman spectra of bacterial cytochromes. | resonance raman spectra were obtained for two newly isolated bacterial cytochromes, alcaligenes faecalis (atcc 8750) c554 and alcaligenes faecalis c556. their spectra were compared with those of mammalian cytochrome c and two other bacterial cytochromes, paracoccus denitrificans c550 and pseudomonas aeruginosa c551. the positions of the raman bands indicated that, while al. c554 and al. c556 were c-type cytochromes with two thioether linkages, several common features found in their raman spectra ... | 1985 | 2982314 |
| the paracoccus denitrificans cytochrome aa3 has a third subunit. | the presence of a third polypeptide subunit in paracoccus cytochrome c oxidase is demonstrated. this protein (apparent molecular mass 23 kda) binds dicyclohexylcarbodiimide in membranes of aerobically grown bacteria and in the purified enzyme. the n-terminal amino-acid sequence of this dicyclohexylcarbodiimide-binding protein is identical to the deduced sequence of the coiii gene product [raitio et al. (1987) embo j. 6, 2825-2833]. we conclude that the aa3-type oxidase in paracoccus is composed ... | 1988 | 2832167 |
| kinetics of the interaction of the cytochrome c oxidase of paracoccus denitrificans with its own and bovine cytochrome c. | we have devised a relatively simple method for the purification of cytochrome aa3 of paracoccus denitrificans with three major subunits similar to those of the larger subunits of the mitochondrial cytochrome oxidase. this preparation has no c-type cytochrome. studies were made of the oxidation of soluble cytochromes c from bovine heart and paracoccus. the cytochrome-c oxidase activity was stimulated by low concentrations of either cytochrome c, providing an explanation for the multiphasic nature ... | 1988 | 2833305 |
| 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 |
| helix movements and the reconstruction of the haem pocket during the evolution of the cytochrome c family. | analysis of cytochromes c (tuna), c2 (rhodospirillum rubrum), c550 (paracoccus denitrificans) and c551 (pseudomonas aeruginosa) shows that they contain 48 residues identifiable as homologous from superposition of the structures. the other 34 to 64 residues are in loops that vary greatly in sequence, length and conformation, or in alpha-helices that are found in only some of the structures. of the 48 homologous residues, 17 are in three segments which pack onto the haem faces. in all four structu ... | 1985 | 2987508 |
| the amino acid sequence of the cytochrome c-554(547) from the chemolithotrophic bacterium thiobacillus neapolitanus. | an amino acid sequence is proposed for the cytochrome c-554(547) from the bacterium thiobacillus neapolitanus n.c.i.b. 8539). it consists of a polypeptide chain of 91 residues, with a pair of haem-attachment cysteine residues at positions 15 and 18. there is similarity in sequence with each of the halves of the sequence of the dihaem cytochromes c4 and with a cytochrome c-554(548) from a halophilic strain of paracoccus. detailed evidence for the amino acid sequence of the protein has been deposi ... | 1985 | 2988504 |
| complexity in the redox titration of the dihaem cytochrome c4. | redox titration of the dihaem, two domain cytochromes c4 from pseudomonas aeruginosa, pseudomonas stutzeri and azotobacter vinelandii showed complex behaviour indicative of the presence of two redox components. in the case of the p. stutzeri cytochrome c4, two spectroscopically distinct components were present during the redox titration. in contrast, cytochrome c-554(548) from a halophilic paracoccus species is a stable dimer of a monohaem cytochrome which shows close homology to cytochrome c4, ... | 1985 | 2990552 |
| the role of subunit iii in bovine cytochrome c oxidase. comparison between native, subunit iii-depleted and paracoccus denitrificans enzymes. | in order to obtain information on the role of subunit iii in the function and aggregation state of cytochrome c oxidase, the kinetics of ferrocytochrome c oxidation by the bovine cytochrome c oxidase depleted of its subunit iii were studied and compared with those of the oxidase isolated from p. denitrificans which contains only two subunits. the aggregation state of both enzymes dispersed in dodecyl maltoside was also compared. the two-subunit oxidase from p. denitrificans gave linear eadie-hof ... | 1985 | 2990554 |
| intraliposomal nucleotides change the kinetics of reconstituted cytochrome c oxidase from bovine heart but not from paracoccus denitrificans. | isolated cytochrome c oxidases of p. denitrificans and bovine heart were reconstituted in liposomes and the kinetics of cytochrome c oxidation were measured in the presence and absence of nucleotides either inside or outside of proteoliposomes, and after photolabelling with 8-azido-atp. intraliposomal atp increases and adp decreases the kinetics of ferrocytochrome c oxidation of the bovine but not of the paracoccus enzyme. extra-liposomal atp and adp increase the km for cytochrome c of both enzy ... | 1988 | 2838021 |
| 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 |
| helical packing in the hydrophobic sector of cytochrome c oxidase. | an arrangement for the membrane-spanning segments of the three larger subunits of cytochrome c oxidase is proposed on the basis of sequence comparison and polarity distribution estimated from the data available for 11 different organisms. | 1985 | 2991455 |
| cloning of paracoccus cytochrome c oxidase subunit ii. | cytochrome c oxidase from paracoccus denitrificans is composed of two subunits, yet is active in both electron transport and proton translocation. a cloning approach and immunologic screening protocol is described for the isolation of the subunit ii gene expressed in e. coli. dna sequencing should establish the extent of homology to eukaryotic oxidase. | 1985 | 2991456 |
| steady-state nitric oxide concentrations during denitrification. | three species of denitrifying bacteria, paracoccus denitrificans, pseudomonas stutzeri strain jm300, and achromobacter cycloclastes, were allowed to reduce nitrate or nitrite in anaerobic, closed vials while the equilibration of gases between aqueous and gas phases was facilitated by vigorous stirring. the gas phase was sampled and analyzed for no with use of a chemiluminescence detector calibrated against bottled no standards or against no produced by the nitrite-iodide reaction. [noaq] was inf ... | 1990 | 2365685 |
| an inducible periplasmic blue copper protein from paracoccus denitrificans. purification, properties, and physiological role. | when grown on methylamine as a sole carbon source, paracoccus denitrificans synthesizes a type i blue copper protein which mediates electron transfer between methylamine dehydrogenase and cytochrome c. this blue copper protein does not serve as an electron acceptor for methanol dehydrogenase and is not synthesized by cells grown on methanol or succinate. the blue copper protein and methylamine dehydrogenase were localized in the periplasm of p. denitrificans, whereas formate dehydrogenase was cy ... | 1985 | 2997215 |
| immunological identification of aa3-type cytochrome oxidase in membrane preparations of the cyanobacterium anacystis nidulans. | membranes were isolated from the cyanobacterium anacystis nidulans by french press extrusion of lysozyme-treated cells. the membranes were solubilized with sodium dodecylsulfate and subjected to denaturing polyacrylamide gel electrophoresis. separated polypeptides were transferred to nitrocellulose by western blotting, and incubated with antibodies against aa3-type cytochrome oxidase of paracoccus denitrificans; antibodies against subunits i and ii, and against the holoenzyme, were used and gave ... | 1986 | 3010964 |
| characterization of two inducible periplasmic c-type cytochromes from paracoccus denitrificans. | when grown on methanol or methylamine, paracoccus denitrificans synthesized three periplasmic soluble c-type cytochromes, cytochrome c550 and two additional cytochromes which were not present during growth on succinate and have not previously been characterized. these cytochromes have been separated from each other and their physical properties have been determined. the inducible cytochromes, c551i and c553i, exhibit mr and pi values of 22,000 and 3.5, and 30,000 and 3.8, respectively. cytochrom ... | 1986 | 3013855 |
| evolutionary relationship of denitrifying bacteria as deduced from 5s rrna sequences. | the nucleotide sequences of 5s rrna from seven denitrifying bacteria have been determined. based on these sequences and those reported in the literature (including two denitrifiers), a phylogenic tree of 104 eubacterial 5s rrna sequences has been constructed to establish the position of the denitrifying bacteria. these bacteria belong to either one of the three major subgroups of gram-negative bacteria. the grouping based on 5s rrna sequences is almost compatible with the type of the nitrite red ... | 1986 | 2434470 |
| a bacterial c-type cytochrome can be translocated to the periplasm as an apo form; the biosynthesis of cytochrome cd1 (nitrite reductase) from paracoccus denitrificans. | an apo form of cytochrome cd1 (nitrite reductase) of paracoccus denitrificans has been detected immunologically in the periplasm of a mutant that lacks all c-type cytochromes. a method for the preparation of apo-nitrite reductase (lacking both c- and d-type haem) from the holoenzyme of wild-type cells has been developed. the apoprotein synthesized by the mutant is indistinguishable from the chemically prepared apoprotein in respect of: (i) subunit molecular weight; (ii) formation of a homodimer; ... | 1989 | 2548064 |
| 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 |
| purification and some characteristics of nitric oxide reductase-containing vesicles from paracoccus denitrificans. | nitric oxide reductase of paracoccus denitrificans was purified, with the use of 3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propanesulfonate (chapso) detergent, as membrane vesicles of apparent mr = 2-3 x 10(6). fifty percent of the protein was a peptide of mr = 34,000. further fractionation with sodium dodecyl sulfate (sds) resulted in vesicles in which the peptide constituted 90-95% of the protein. this peptide, which is rich in ala, gly, ser, asx, and glx, is considered to be the pept ... | 1989 | 2708379 |
| 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 |
| subunit ii of cytochrome c oxidase from paracoccus denitrificans. dna sequence, gene expression and the protein. | cytochrome c oxidase from the bacterium paracoccus denitrificans, while being related to the mitochondrial enzyme in many ways, consists of only two to three different subunits. for the identification of its genes, a paracoccus dna library was constructed and screened with specific antibodies for expression of cloned inserts in e. coli. a positive clone expressing immunoreactive products in the molecular mass region of authentic subunit ii revealed a high homology of its dna-deduced amino acid s ... | 1987 | 2820725 |
| protonmotive q cycle pathway of electron transfer and energy transduction in the three-subunit ubiquinol-cytochrome c oxidoreductase complex of paracoccus denitrificans. | ubiquinol-cytochrome c oxidoreductase (cytochrome bc1) complex from paracoccus denitrificans consists of only three polypeptide subunits (yang, x., and trumpower, b. l. (1986) j. biol. chem. 261, 12282-12289), whereas the analogous complexes of eukaryotic mitochondria consist of nine or more polypeptides (schagger, h., link, t. a., engel, w. d., and von jagow, g. (1986) methods enzymol. 126, 224-237). using the purified three-subunit paracoccus complex we have tested whether this simple cytochro ... | 1988 | 2841340 |
| kinetics of the interaction of cytochrome c oxidase of paracoccus denitrificans with paracoccus and mitochondrial cytochrome c. | we have studied the reactions of the oxidase of paracoccus dentrificans with its membrane-bound cytochrome c and with soluble cytochrome c550 of paracoccus and of bovine heart. the turnover rate of paracoccus oxidase with membrane-bound cytochrome c is high, approaching 1000/sec. at 25 degrees. when soluble cytochrome c is added to the electron transport chain oxidizing nadh or succinate, no increase in 02 uptake is observed. when the oxidase is reacting with the membrane-bound cytochrome c, the ... | 1988 | 2841681 |
| evolution of cytochrome c oxidase. | the current view on the regulatory function of nuclear-encoded subunits of cytochrome c oxidase from higher evolved organisms is presented. the activity of monomeric laurylmaltoside-dissolved, but not of reconstituted cytochrome c oxidase, is strongly affected by anions accompanied by a conformational change of the enzyme, as shown by changed visible spectra. addition of uncoupler to proteoliposomes induces the same anion sensitivity as obtained with the soluble enzyme, suggesting dissociation o ... | 1988 | 2841683 |
| proteolysis of paracoccus denitrificans cytochrome oxidase by trypsin and chymotrypsin. | paracoccus oxidase containing only two subunits was subjected to proteolysis by trypsin and chymotrypsin. both subunits of the purified enzyme were cleaved at only a few sites and enzymatic activity was not inhibited. the cleavage sites were identified by protein sequencing. subunit i was cleaved near the amino-terminus and subunit ii in the loop connecting the two predicted trans-membrane helices. in native membrane fragments, but not in intact spheroplasts, this loop was accessible to both pro ... | 1988 | 2842192 |
| purification and properties of succinate-ubiquinone oxidoreductase complex from paracoccus denitrificans. | highly active succinate-ubiquinone reductase has been purified from cytoplasmic membranes of aerobically grown paracoccus denitrificans. the purified enzyme has a specific activity of 100 units per mg protein, and a turnover number of 305 s-1. succinate-ubiquinone reductase activity of the purified enzyme is inhibited by 3'-methylcarboxin and thenoyltrifluoroacetone. four subunits, with apparent molecular masses of 64.9, 28.9, 13.4 and 12.5 kda, were observed on sodium dodecyl sulfate polyacryla ... | 1988 | 2843228 |
| subunit ii of the paracoccus denitrificans cytochrome c oxidase. expression studies of its cloned gene in e. coli. | | 1988 | 2854402 |
| cytochrome o from escherichia coli is structurally related to cytochrome aa3. | | 1988 | 2854403 |
| some spectroscopic views of the cua site in cytochrome c oxidase preparations. | | 1988 | 2854410 |
| cytochrome c oxidase from paracoccus denitrificans. | | 1986 | 2856122 |
| isolation of ubiquinol oxidase from paracoccus denitrificans. | | 1986 | 2856133 |
| isolation of a three-subunit cytochrome bc1 complex from paracoccus denitrificans. | | 1986 | 2856134 |
| a simple, one-step purification for cytochrome b from the bc1 complexes of bacteria. | | 1986 | 2856136 |
| growth of paracoccus denitrificans on [2,3-13c]succinate and [1,4-13c]succinate. i. the flux of carbon in energy metabolism and the operation of the tca cycle. | the metabolism of paracoccus denitrificans, grown on either [2,3-13c]succinate or [1,4-13c]succinate, was investigated by using gas chromatography-mass spectrometry. the distribution of label in a group of metabolites closely related to the tca-cycle intermediates showed that the flux of carbon from succinate in energy metabolism in vivo was via pyruvate (malic enzyme) and acetyl coa. the labelling pattern of the carboxyl groups showed that one fifth of the succinate pool was formed by the regen ... | 1987 | 2888121 |
| growth of paracoccus denitrificans on [2,3-13c]succinate and [1,4-13c]succinate. ii. isoleucine biosynthesis. | paracoccus denitrificans was grown on either [2,3-13c]succinate or [1,4-13c]succinate, and extracts were analysed by using gas chromatography-mass spectrometry. the distribution of label in isoleucine indicated that the 2-ketobutyrate required for isoleucine biosynthesis was mainly produced from pyruvate by 2-keto-acid chain elongation (i.e. the 'pyruvate elongation pathway'). approximately 10% of isoleucine was produced by a second pathway involving propionyl coa. threonine and glutamate were n ... | 1987 | 2888122 |
| isolation of ubiquinol oxidase from paracoccus denitrificans and resolution into cytochrome bc1 and cytochrome c-aa3 complexes. | an enzyme complex with ubiquinol-cytochrome c oxidoreductase, cytochrome c oxidase, and ubiquinol oxidase activities was purified from a detergent extract of the plasma membrane of aerobically grown paracoccus denitrificans. this ubiquinol oxidase consists of seven polypeptides and contains two b cytochromes, cytochrome c1, cytochrome aa3, and a previously unreported c-type cytochrome. this c-type cytochrome has an apparent mr of 22,000 and an alpha absorption maximum at 552 nm. retention of thi ... | 1985 | 2982819 |
| spectroscopic and functional properties of subunit iii-depleted cytochrome oxidase. | beef heart cytochrome c oxidase has been depleted of subunit iii by treatment with chymotrypsin. the removal of subunit iii has been evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel fluorography of preparations of the oxidase labeled with [14c]dicyclohexylcarbodiimide prior to proteolysis. removal of subunit iii resulted in a perturbation of the visible spectrum of reduced cytochrome oxidase. subunit iii-depleted oxidase is spectroscopically very similar to the oxid ... | 1985 | 2982875 |
| osmotic effects on bacterial transport and energetics. | paracoccus denitrificans suspended in media containing 20-300 mm nacl swelled progressively as the salt concentration was decreased. the increase in intracellular water volume was accompanied by an enhancement of respiration and a stimulation of the rates of net potassium and alpha-aminoisobutyric acid accumulation. it is postulated that influx of water and consequent lowering of intracellular solute concentration trigger transport mechanisms which are destined to restore the original ion and me ... | 1985 | 2991018 |
| monoclonal antibodies to cytochrome c from paracoccus denitrificans: effects on electron transport reactions. | the effect of a monoclonal antibody to a soluble cytochrome c from paracoccus denitrificans was tested on the membrane-bound electron-transport system of this bacterium. this antibody (f3-10.2) and one previously described (f3-29.4) (kuo, l.m., davies, h.c. and smith, l. (1984) biochim. biophys. acta 766, 472-482) were deduced to bind to the cytochrome c in the area including amino acid residue number 23 on a loop on the side of the heme crevice. in contrast to the observations with the previous ... | 1985 | 2994723 |
| cytochrome c oxidase from paracoccus denitrificans in triton x-100: aggregation state and kinetics. | cytochrome c oxidase from paracoccus denitrificans was homogeneously dispersed in triton x-100. using gel exclusion chromatography and sucrose gradient centrifugation analysis a molecular weight of the detergent-protein complex of 155,000 was determined. after subtraction of the bound detergent (111 mol/mol heme aa3) a molecular weight of 85,000 resulted, which agreed well with the model of a monomer containing two subunits. this monomer showed high cytochrome c oxidase activity when measured sp ... | 1986 | 3017928 |
| purification of a three-subunit ubiquinol-cytochrome c oxidoreductase complex from paracoccus denitrificans. | a ubiquinol-cytochrome c oxidoreductase (cytochrome bc1) complex has been purified from the plasma membrane of aerobically grown paracoccus denitrificans by extraction with dodecyl maltoside and ion exchange chromatography of the extract. the purified complex contains two spectrally and thermodynamically distinct b cytochromes, cytochrome c1, and a rieske-type iron-sulfur protein. optical spectra indicate absorption peaks at 553 nm for cytochrome c1 and at 560 and 566 nm for the high and low pot ... | 1986 | 3017970 |
| a gene in paracoccus for subunit iii of cytochrome oxidase. | the region of paracoccus denitrificans chromosome where the genes coding for cytochrome oxidase (cytochrome aa3) subunits are located has been cloned. dna sequencing revealed an open reading frame that codes for a protein homologous to the subunit iii of the eukaryotic, mitochondrial enzyme. this subunit is absent from the isolated paracoccus oxidase. it now seems that it is part of the native enzyme in the bacterial cytoplasmic membrane. this may explain the observed discrepancies in the functi ... | 1986 | 3019767 |
| bacterial oxidation of methane and methanol. | | 1986 | 3020939 |
| measurement of the oxidation-reduction potentials of amicyanin and c-type cytochromes from paracoccus denitrificans. | the oxidation-reduction potentials of four periplasmic electron carrier proteins from paracoccus denitrificans have been determined. their midpoint potentials are: amicyanin, 294 +/- 6 mv; cytochrome c-550, 253 +/- 5 mv; cytochrome c-551i, 190 +/- 4 mv; and cytochrome c-553i, 148 +/- 5 mv. although rapid amicyanin-mediated transfer of electrons from methylamine dehydrogenase to cytochrome c-551i was observed, reduced amicyanin did not reduce oxidized cytochrome c-551i in the absence of methylami ... | 1986 | 3021532 |
| electron-transfer reactions between flavodoxin semiquinone and c-type cytochromes: comparisons between various flavodoxins. | as an extension of previous work from this laboratory using clostridium pasteurianum flavodoxin [tollin, g., cheddar, g., watkins, j. a., meyer, t. e., & cusanovich, m. a. (1984) biochemistry 23, 6345-6349], we have measured the rate constants as a function of ionic strength for electron transfer from the semiquinones of clostridium mp, anacystis nidulans, and azotobacter vinelandii flavodoxins to the following oxidants: cytochrome c from tuna and horse, paracoccus denitrificans cytochrome c2, p ... | 1986 | 3024711 |
| detergent inhibition of nitric-oxide reductase activity. | gas chromatography revealed that exposure of extracts of the denitrifiers 'achromobacter cycloclastes', paracoccus denitrificans, pseudomonas aeruginosa and pseudomonas perfectomarina to triton x-100 inhibited reduction of no to n2o, and thus concomitantly inhibited reduction of no2- to n2o. after exposure of extracts to triton x-100, the ratio of h+ consumed to no2- added decreased from approx. 2.0 (for untreated extracts) to approx. 1.5, which indicated that no2- was reduced to no by the treat ... | 1987 | 3028488 |
| a simple, one-step purification of cytochrome b from the bc1 complexes of bacteria. | | 1987 | 3030803 |
| laser flash photolysis studies of electron transfer between ferredoxin-nadp+ reductase and several high-potential redox proteins. | complex formation and the kinetics of electron transfer between ferredoxin-nadp+ reductase (fnr) and two structurally homologous acidic 4fe-4s high-potential ferredoxins (hipip's) from ectothiorhodospira halophila (hp1 and hp2) and two structurally homologous cytochromes c2 from paracoccus denitrificans and rhodospirillum rubrum (pc2, and rc2, respectively) have been investigated by gel filtration and laser flash photolysis techniques. gel filtration studies indicated that complex formation occu ... | 1987 | 3032236 |
| cytochrome c oxidase is a three-copper, two-heme-a protein. | metal contents of preparations of procaryotic (paracoccus denitrificans) and eucaryotic (beef heart) cytochrome c oxidases have been determined by inductively coupled plasma atomic emission spectroscopy and shown to be stoichiometrically related to the protein contents. the results show that oxidases which possess subunits i and ii have three copper atoms besides hemes a and a3 (paracoccus denitrificans, cu: 2.97 +/- 0.08 and fe: 2.09 +/- 0.10; bovine heart, cu: 2.83 +/- 0.07 and fe: 1.94 +/- 0. ... | 1987 | 3032614 |
| homology between bacterial dna and bovine mitochondrial dna encoding cytochrome c oxidase subunit iii. | a segment of mitochondrial dna encoding the bovine cytochrome c oxidase subunit iii gene was isolated and inserted into an escherichia coli plasmid vector. a 556 base pair fragment of the insert dna representing about 70% of the 3'-end of the subunit iii gene was used to search for homology with bacterial dna from strains that contain heme aa3-type cytochrome c oxidases. bacillus subtilis, thermus thermophilus, and ps3 dnas all showed strong hybridization to the probe, whereas paracoccus denitri ... | 1987 | 3032681 |
| purification and some characteristics of nitrous oxide reductase from paracoccus denitrificans. | nitrous oxide reductase from the denitrifying bacterium paracoccus denitrificans has been purified very nearly to homogeneity by an anaerobic procedure that results in a product with high specific activity. the enzyme is a dimer of about mr 144,000 composed of two subunits of apparently equal mr and contains 4 mol of cu per mol of subunit. the isoelectric point is 4.3; specific activity at 25 degrees c, ph 7.1, is 122 mumol x min-1 x mg of protein-1; and km is about 7 microm n2o under the same c ... | 1987 | 3032972 |