| purification and properties of an nad(p)+-linked formaldehyde dehydrogenase from methylococcus capsulatus (bath). | crude soluble extracts of methylococcus capsulatus strain bath, grown on methane, were found to contain nad(p)+-linked formaldehyde dehydrogenase activity. activity in the extract was lost on dialysis against phosphate buffer, but could be restored by supplementing with inactive, heat-treated extract (70 degrees c for 12 min). the non-dialysable, heat-sensitive component was isolated and purified, and has a molecular weight of about 115000. sodium dodecyl sulphate gel electrophoresis of the prot ... | 1978 | 32222 |
| intracytoplasmic membrane, phospholipid, and sterol content of methylobacterium organophilum cells grown under different conditions. | intracytoplasmic membranes were present in methylobacterium organophilum when cells were grown with methane, but not methanol or glucose, as the sole carbon and energy source. cells grown with methane as the carbon and energy source and low levels of dissolved oxygen had the greatest amount of intracytoplasmic membrane. cells grown with increased levels of dissolved oxygen had less intracytoplasmic membrane. the amount of total lipid correlated with the amount of membrane material observed in th ... | 1978 | 96093 |
| a comparison of the substrate and electron-donor specificities of the methane mono-oxygenases from three strains of methane-oxidizing bacteria. | 1. methane mono-oxygenase from methylosinus trichosporium has the same broad substrate specificity as the analogous enzyme from methylococcus capsulatus (bath); the enzyme from methylomonas methanica is more specific. 2. contrary to previous reports, nad(p)h and not ascorbate is the required electron donor for the enzyme from methylosinus trichosporium. 3. it is concluded that these three bacteria contain similar methane mono-oxygenases. | 1979 | 106847 |
| membrane modulation in a methylotrophic bacterium methylococcus capsulatus (texas) as a function of growth substrate. | methylococcus capsulatus (texas), when grown on methane, undergoes with age a progressive degeneration of internal membrane structure with a simultaneous accumulation of intracellular inclusions. when m. capsulatus is grown on methanol, virtually no internal membranes are present but, instead, cells contain many intracellular droplets morphologically similar to inclusions in old methane-grown cells. membranes are regenerated by the cells when a methanol-grown culture is transferred back to metha ... | 1979 | 118544 |
| the soluble methane mono-oxygenase of methylococcus capsulatus (bath). its ability to oxygenate n-alkanes, n-alkenes, ethers, and alicyclic, aromatic and heterocyclic compounds. | 1. methane mono-oxygenase of methylococcus capsulatus (bath) catalyses the oxidation of various substituted methane derivatives including methanol. 2. it is a very non-specific oxygenase and, in some of its catalytic properties, apparently resembles the analogous enzyme from methylomonas methanica but differs from those found in methylosinus trichosporium and methylomonas albus. 3. co is oxidized to co2. 4. c1-c8 n-alkanes are hydroxylated, yielding mixtures of the corresponding 1- and 2-alcohol ... | 1977 | 411486 |
| resolution of the methane mono-oxygenase of methylococcus capsulatus (bath) into three components. purification and properties of component c, a flavoprotein. | 1. ion-exchange chromatography resolves the methane mono-oxygenase from soluble extracts of methylococcus capsulatus (bath) into three fractions. 2. fractions a and b are comparatively stable at 0 degrees c, whereas fraction c is very unstable unless kept in the presence of sodium thioglycollate (1-10 mm) or dithiothreitol (5-10mm). 3. the active component from fraction c was purified some 80-fold. 4. purified component c has mol. wt. 42000. its solutions are yellow with absorption maxima at 270 ... | 1978 | 418777 |
| speculations on the evolution of sterol structure and function. | the essential oxygen requirement for sterol biosynthesis dates this molecule as a relative latecomer in cellular evolution. structural details of the cholesterol molecule and related sterols can be rationalized in terms of optimal hydrophobic interactions between the planar sterol ring system and phospholipid acyl chains in the membrane bilayer. the prediction that the cholesterol precursor lanosterol (4,4',14 trimethyl cholastadienol) is incompetent for membrane function is verified by in vivo ... | 1979 | 498798 |
| incomplete tricarboxylic acid cycle in a type i methylotroph, methylococcus capsulatus. | alpha-ketoglutaratedehydrogenase was undetectable in extracts of methylococcus capsulatus. cells incorporated [1-14-c] acetate into only four protein amino acids (glutamate, proline, arginine, and leucine) and the c5, but not c1, of glutamate. | 1975 | 806581 |
| [isolation of bacteriophages of methane oxidizing bacteria and study of their properties]. | five strains of bacteriophages were isolated for the first time in the ussr from the water of ponds, the paste of methane oxidizing bacteria and the cultural broth of the experimental plant. the strains are specific of the following species: methylostinus sporium, methylosinus trichosporium, and flavobacterium gasotypicum. bacteriophages lysing methylocystis impression. methylomonas agile and methylococcus capsulatus were not isolated so far. the fine structure of the phages, the shape of negati ... | 1976 | 827665 |
| screening for restriction endonucleases in methane-oxidizing bacteria. | 51 methane-oxidizing bacteria strains such as methylomonas methanica, m. rubra, methylococcus capsulatus, m. thermophilus, m. luteus, m. ucrainicus, m. whittenburyi, methylosinus trichosporium, m. sporium, methylocystis parvus isolated from various ecological niches and geographical regions of the ukraine and also the strains received from r. whittenbury and y. heyer were screened for restriction endonucleases. type ii restriction endonucleases were detected in imv b-3112 (= 12 b), imv b-3027 (= ... | 1992 | 1338116 |
| soluble methane monooxygenase component b gene probe for identification of methanotrophs that rapidly degrade trichloroethylene. | restriction fragment length polymorphisms, western blot (immunoblot) analysis, and fluorescence-labelled signature probes were used for the characterization of methanotrophic bacteria as well as for the identification of methanotrophs which contained the soluble methane monooxygenase (mmo) gene and were able to degrade trichloroethylene (tce). the gene encoding a soluble mmo component b protein from methylosinus trichosporium ob3b was cloned. it contained a 2.2-kb ecori fragment. with this clone ... | 1992 | 1349468 |
| crystallization and preliminary x-ray analysis of the methane monooxygenase hydroxylase protein from methylococcus capsulatus (bath). | methane monooxygenase is a multicomponent enzyme system that catalyzes the conversion of methane to methanol in methanotrophic bacteria. catalysis occurs at non-heme dinuclear iron centers contained in the hydroxylase component of the system, a dimer of composition alpha 2 beta 2 gamma 2. the hydroxylase protein from methylococcus capsulatus (bath) has been crystallized from aqueous solutions containing polyethylene glycol, lithium sulfate, and ammonium acetate. the crystals are orthorhombic, sp ... | 1992 | 1404375 |
| 16s ribosomal rna sequence analysis for determination of phylogenetic relationship among methylotrophs. | 16s ribosomal rnas (rrna) of 12 methylotrophic bacteria have been almost completely sequenced to establish their phylogenetic relationships. methylotrophs that are physiologically related are phylogenetically diverse and are scattered among the purple eubacteria (class proteobacteria). group i methylotrophs can be classified in the beta- and the gamma-subdivisions and group ii methylotrophs in the alpha-subdivision of the purple eubacteria, respectively. pink-pigmented facultative and non-pigmen ... | 1990 | 1693657 |
| further characterisation of the fad and fe2s2 redox centres of component c, the nadh:acceptor reductase of the soluble methane monooxygenase of methylococcus capsulatus (bath). | the absorbance contributions of the fad and fe2s2 redox centres of component c of the soluble methane monooxygenase complex have been resolved, using mersalyl to destroy the fe2s2 centre. the fe2s2 seems to be very similar to that of spinach ferredoxin, by its absorbance and electron paramagnetic resonance (epr) spectra, and the fad semiquinone is a neutral semiquinone. spectrophotometry near room temperature and epr spectroscopy near liquid-helium temperature allow the three redox couples of co ... | 1985 | 2982614 |
| inhibition of dimethyl ether and methane oxidation in methylococcus capsulatus and methylosinus trichosporium. | metal-chelating or -binding agents inhibited the oxidation of dimethyl ether and methane, but not methanol, by cell suspensions of methylococcus capsulatus and methylosinus trichosporium. evidence suggests that the involvement of metal-containing enzymatic systems in the initial step of oxidation of dimethyl ether and methane. | 1976 | 4428 |
| the amino acid sequence of cytochrome c-555 from the methane-oxidizing bacterium methylococcus capsulatus. | the amino acid sequence of the cytochrome c-555 from the obligate methanotroph methylococcus capsulatus strain bath (n.c.i.b. 11132) was determined. it is a single polypeptide chain of 96 residues, binding a haem group through the cysteine residues at positions 19 and 22, and the only methionine residue is a position 59. the sequence does not closely resemble that of any other cytochrome c that has yet been characterized. detailed evidence for the amino acid sequence of the protein has been depo ... | 1986 | 3006666 |
| the biosynthesis and assembly of protein a of soluble methane monooxygenase of methylococcus capsulatus (bath). | protein a of soluble methane monooxygenase (ec 1.14.13.25) of methylococcus capsulatus (bath) is the hydroxylase component of the enzyme complex, capable of inserting an atom of oxygen into methane. the protein possesses an unusual non-heme iron center consisting of two mu-hydroxo-bridged antiferromagnetically coupled iron atoms. it was possible to remove the iron center of protein a by subjecting the protein to freeze/thaw cycles or by dialysis against 8-hydroxyquinoline. incubation of iron-dep ... | 1988 | 2846569 |
| identification of putative methanol dehydrogenase (moxf) structural genes in methylotrophs and cloning of moxf genes from methylococcus capsulatus bath and methylomonas albus bg8. | an open-reading-frame fragment of a methylobacterium sp. strain am1 gene (moxf) encoding a portion of the methanol dehydrogenase structural protein has been used as a hybridization probe to detect similar sequences in a variety of methylotrophic bacteria. this hybridization was used to isolate clones containing putative moxf genes from two obligate methanotrophic bacteria, methylococcus capsulatus bath and methylomonas albus bg8. the identity of these genes was confirmed in two ways. a t7 expres ... | 1988 | 3129400 |
| substrate specificity of soluble methane monooxygenase. mechanistic implications. | following the example set by studies of the mechanistic aspects of the substrate specificity of various cytochrome p-450 enzymes, we have undertaken a parallel investigation of the soluble methane monooxygenase from methylococcus capsulatus (bath). soluble methane monooxygenase is a multicomponent enzyme with a broad substrate specificity. using substrates previously tested with cytochrome p-450 enzymes and using purified enzyme preparations, this work indicates that soluble methane monooxygenas ... | 1989 | 2808342 |
| molecular analysis of methane monooxygenase from methylococcus capsulatus (bath). | methane monooxygenase (mmo) is the enzyme responsible for the conversion of methane to methanol in methanotrophic bacteria. in addition, this enzyme complex oxidizes a wide range of aliphatic and aromatic compounds in a number of potentially useful biotransformations. in this study, we have used biochemical data obtained from purification and characterization of the soluble mmo from methylococcus capsulatus (bath), to identify structural genes encoding this enzyme by oligonucleotide probing. the ... | 1989 | 2505721 |
| solubilisation of methane monooxygenase from methylococcus capsulatus (bath). | the membrane-bound (particulate) form of methane monooxygenase from methylococcus capsulatus (bath) has been solubilised using the non-ionic detergent dodecyl-beta-d-maltoside. a wide variety of detergents were tested and found to solubilise membrane proteins but did not yield methane monooxygenase in a form that could be subsequently activated. after solubilisation with dodecyl-beta-d-maltoside, enzyme activity was recovered using either egg or soya-bean lipids. attempts to further purify the s ... | 1989 | 2502395 |
| a stopped-flow kinetic study of soluble methane mono-oxygenase from methylococcus capsulatus (bath). | 1. the roles of the three protein components of soluble methane mono-oxygenase were investigated by the use of rapid-reaction techniques. the transfer of electrons through the enzyme complex from nadh to methane/o2 was also investigated. 2. electron transfer from protein c, the reductase component, to protein a, the hydroxylase component, was demonstrated. protein c was shown to undergo a three-electron--one-electron catalytic cycle. the interaction of protein c with nadh was investigated. reduc ... | 1989 | 2497729 |
| novel hopanoids from the methylotrophic bacteria methylococcus capsulatus and methylomonas methanica. (22s)-35-aminobacteriohopane-30,31,32,33,34-pentol and (22s)-35-amino-3 beta-methylbacteriohopane-30,31,32,33,34-pentol. | the major hopanoid of the methylotrophic bacteria methylococcus capsulatus and methylomonas methanica was identified by spectroscopic methods as (22s)-35-aminobacteriohopane-30,31,32,33,34-pentol. minor companions were, in both bacteria, 35-aminobacteriohopane-31,32,33,34-tetrol and in methylomonas methanica, 35-aminobacteriohopane-32,33,34-triol. in methylococcus capsulatus the aminopentol and the aminotetrol were accompanied by their homologues possessing an extra methyl group at c-3. bacteria ... | 1985 | 3935106 |
| physiological studies of methane- and methanol-oxidizing bacteria: immunological comparison of a primary alcohol dehydrogenase from methylococcus capsulatus and pseudomonas sp. m27. | a primary alcohol dehydrogenase was purified from cell extracts of two apparently unrelated microorganisms, namely, pseudomonas sp. m27 and methylococcus capsulatus. rabbit antiserum prepared against the purified enzyme from m. capsulatus revealed distinctive antigenic determinants by quantitative and gel precipitin reactions. rabbit antiserum to m27 enzyme detected both distinctive and shared antigenic determinants. certain methane- and methanol-oxidizing bacteria were grouped on the basis of s ... | 1973 | 4120569 |
| the methane monooxygenase gene cluster of methylococcus capsulatus (bath). | methane is oxidised to methanol in methanotrophic bacteria by the enzyme methane monooxygenase (mmo). methylococcus capsulatus (bath) produces a soluble mmo which oxidises a range of aliphatic and aromatic compounds with potential for commercial exploitation. this multicomponent enzyme has been extensively characterised and biochemical data have been used to identify a 12-kb fragment of methylococcus dna carrying the structural genes mmoy and mmoz, coding for the beta- and gamma-subunits of mmo ... | 1990 | 2205538 |
| the carbon assimilation pathways of methylococcus capsulatus, pseudomonas methanica and methylosinus trichosporium (ob3b) during growth on methane. | d-arabino-3-hexulose 6-phosphate was prepared by condensation of formaldehyde with ribulose 5-phosphate in the presence of 3-hexulose phosphate synthase from methane-grown methylococcus capsulatus. the 3-hexulose phosphate was unstable in solutions of ph greater than 3, giving a mixture of products in which, after dephosphorylation, allulose and fructose were detected. a complete conversion of d-ribulose 5-phosphate and formaldehyde into d-fructose 6-phosphate was demonstrated in the presence of ... | 1974 | 4377654 |
| cloning, sequencing and expression of the glutamine synthetase structural gene (glna) from the obligate methanotroph methylococcus capsulatus (bath). | the structural gene (glna) encoding the ammonia-assimulation enzyme glutamine synthetase (gs) has been cloned from the obligate methanotroph methylococcus capsulatus (bath). complementation of escherichia coli glna mutants was demonstrated. in vitro expression analysis revealed that the cloned glna gene coded for a polypeptide of apparent mr 60,000, as determined by page. expression of the m. capsulatus (bath) glna gene in e. coli was regulated by nitrogen levels in an ntr+ but not an ntr- backg ... | 1990 | 1969923 |
| oxidation of deuterated compounds by high specific activity methane monooxygenase from methylosinus trichosporium. mechanistic implications. | hydrocarbon oxidations catalyzed by methane monooxygenase purified to high specific activity from the type ii methanotroph methylosinus trichosporium ob3b were compared to the same reactions catalyzed by methane monooxygenase from the type i methanotroph methylococcus capsulatus bath and liver microsomal cytochrome p-450. the two methane monooxygenases produced nearly identical product distributions, in accord with physical studies of the enzymes which have shown them to be very similar. the pro ... | 1991 | 1917992 |
| cloning of nitrogenase structural genes from the obligate methanotroph methylococcus capsulatus (bath). | southern hybridization techniques were used to examine the dna homologies between the three nitrogenase structural genes nifh, nifd and nifk of klebsiella pneumoniae and dna from the obligate methane oxidizing bacterium methylococcus capsulatus (bath). the high degree of homology between methanotroph dna sequences and the klebsiella nifh and nifd genes was used to isolate and clone the corresponding methylococcus nifh and nifd genes. subsequent restriction analysis revealed that all three nif st ... | 1991 | 1904041 |
| the methane monooxygenase gene cluster of methylosinus trichosporium: cloning and sequencing of the mmoc gene. | methane monooxygenase (mmo) is the enzyme responsible for the conversion of methane to methanol in methanotrophic bacteria. the soluble mmo enzyme complex from methylosinus trichosporium also oxidizes a wide range of aliphatic and aromatic compounds in a number of potentially useful biotransformations. in this study we have used heterologous dna probes from the type x methanotroph methylococcus capsulatus (bath) to isolate mmo genes from the type ii methanotroph m. trichosporium. we report here ... | 1991 | 1785954 |
| redox properties of the hydroxylase component of methane monooxygenase from methylococcus capsulatus (bath). effects of protein b, reductase, and substrate. | the reduction potentials of the hydroxylase component of the soluble methane monooxygenase from methylococcus capsulatus (bath) have been investigated through potentiometric titrations. the potentials were determined by epr spectroscopic quantitation of the mixed valent hydroxylase as a function of added sodium dithionite in the presence of appropriate mediators. the reduction of the oxidized fe(iii).fe(iii) form to the mixed valent fe(ii).fe(iii) form occurs at 48 mv versus nhe while the potent ... | 1991 | 1649166 |
| steroids and squalene in methylococcus capsulatus grown on methane. | | 1971 | 4929985 |
| automatic assessment of respiration during growth in stirred fermentors. | an apparatus for the continuous and automatic measurement of respiration during growth of micro-organisms in stirred aerated culture is described. the effluent atmosphere from the culture vessels is passed through commercially available oxygen and carbon dioxide gas analyzers, and their electrical output is fed to a multipoint recorder. the apparatus has been used to measure the respiration of escherichia coli, pseudomonas aeruginosa, bacillus thuringiensis, and methylococcus capsulatus during g ... | 1969 | 4984766 |
| functional expression in escherichia coli of proteins b and c from soluble methane monooxygenase of methylococcus capsulatus (bath). | methylococcus capsulatus (bath) uses a soluble methane monooxygenase (smmo) to catalyse the oxidation of methane to methanol. smmo is comprised of three components; a, b and c. protein c (the reductase) transfers electrons from nadh to protein a (the hydroxylase) which contains the active site, and protein b regulates this electron flow. the five genes encoding the smmo proteins and their subunits are clustered and have been cloned in escherichia coli. a dna fragment containing mmob, the gene en ... | 1992 | 1512560 |
| delta8(14)-steroids in the bacterium methylococcus capsulatus. | the 4,4-dimethyl and 4alpha-methyl sterols of the bacterium methylococcus capsulatus were identified as 4,4-dimethyl- and 4alpha-methyl-5alpha-cholest-8(14)-en-3beta-ol and 4,4-dimethyl- and 4alpha-methyl-5alpha-cholesta-8(14),24-dien-3beta-ol. sterol biosynthesis is blocked at the level of 4alpha-methyl delta8(14)-sterols. | 1976 | 999649 |
| some properties of a soluble methane mono-oxygenase from methylococcus capsulatus strain bath. | soluble extracts of methylococcus capsulatus (bath), obtained by centrifugation of crude extracts at 160000g for 1h, catalyse the nad(p)h- and o2-dependent disappearance of bromomethane, and also the formation of methanol from methane. soluble methane mono-oxygenase is not inhibited by chelating agents or by most electron-transport inhibitors, and is a multicomponent enzyme. | 1976 | 962879 |
| genetic transformation in methylococcus capsulatus. | | 1971 | 5145030 |
| a possible role of free radicals in the oxidation of methane by methylococcus capsulatus. | | 1976 | 940329 |
| properties of the methane mono-oxygenase from extracts of methylosinus trichosporium ob3b and evidence for its similarity to the enzyme from methylococcus capsulatus (bath). | 1. the methane mono-oxygenase from methylosinus trichosporium ob3b was soluble. the only suitable electron donor was nad(p)h, neither sodium l-ascorbate nor electrons derived from the oxidation of methanol could substitute for nad(p)h. evidence is presented for the existence of an nad+-linked formaldehyde dehydrogenase. 2. mono-oxygenase activity was not inhibited by a range of potential inhibitors including potassium cyanide, amytal, carbon monoxide or various metal-chelating agents, although 8 ... | 1979 | 572296 |
| physiological studies of methane and methanol-oxidizing bacteria: oxidation of c-1 compounds by methylococcus capsulatus. | methylococcus capsulatus grows only on methane or methanol as its sole source of carbon and energy. some amino acids serve as nitrogen sources and are converted to keto acids which accumulate in the culture medium. cell suspensions oxidize methane, methanol, formaldehyde, and formate to carbon dioxide. other primary alcohols are oxidized only to the corresponding aldehydes. oxidation of formate by cell suspensions is more sensitive to inhibition by cyanide than is the oxidation of other one carb ... | 1971 | 5563868 |
| (14c)acetate assimilation by a type i obligate methylotroph, methylococcus capsulatus. | methanol and formate oxidation supported the assimilation of [14c]acetate by cell suspensions of methylococcus capsulatus; oxidation of other primary alcohols, except ethanol, did not. the extent of [1-14c]acetate assimilation supported by methanol oxidation was decreased in the presence of primary alcohols, except ethanol. potassium cyanide (0.33 mm) completely inhibited the oxidation of formate and its stimulation of [1-14c]acetate assimilation. the amount of [1-14c]acetate assimilation suppor ... | 1977 | 412469 |
| effect of metal-binding and other compounds on methane oxidation by two strains of methylococcus capsulatus. | | 1977 | 410382 |
| oxidation of c1 compounds by particulate fractions from methylococcus capsulatus: properties of methanol oxidase and methanol dehydrogenase. | methanol (and formaldehyde) oxidizing activities in crude extracts of methylococcus capsulatus are associated mainly with particulate fractions sedimenting between 3,000 and 40,000 x g. most of the phenazine methosulfate (pms)-dependent methanol (and formaldehyde) dehydrogenase activity observed resides in the soluble fraction but represents only 40% of the total (pms dependent plus independent) activity. both pms-dependent methanol dehydrogenase activity and pms-independent methanol oxidase act ... | 1975 | 238947 |
| oxidation of c1 compounds by particulate fractions from methylococcus capsulatus: distribution and properties of methane-dependent reduced nicotinamide adenine dinucleotide oxidase (methane hydroxylase). | cell-free particulate fractions of extracts from the obligate methylotroph methylococcus capsulatus catalyze the reduced nicotinamide adenine dinucleotide (nadh) and o2-dependent oxidation of methane (methane hydroxylase). the only oxidation product detected was formate. these preparations also catalyze the oxidation of methanol and formaldehyde to formate in the presence or absence of phenazine methosulphate with oxygen as the terminal electron acceptor. methane hydroxylase activity cannot be r ... | 1975 | 238946 |
| characterization of the second prosthetic group of the flavoenzyme nadh-acceptor reductase (component c) of the methane mono-oxygenase from methylococcus capsulatus (bath). | 1. a new two-step purification is described that routinely yields 100mg quantities of component c for biochemical studies. 2. chemical analyses show component c purified by this procedure to contain 2 g-atoms of iron, 2 mol of acid-labile sulphide (s) and 1 mol of fad per mol of protein. 3. the fe-s core of component c was extruded by treating the protein with p-methoxybenzenethiol in hexamethyl phosphoramide/50mm-tris/hcl buffer, ph 8.5 (4:1, v/v), under anaerobic conditions. the spectral prope ... | 1979 | 220953 |
| plasmids in methanotrophic bacteria: isolation, characterization and dna hybridization analysis. | ten strains of obligate methanotrophs were screened for the presence of plasmid dna using a variety of methods. plasmids were detected in all strains except methylococcus capsulatus bath. no significant similarity between plasmids was observed with respect to size or restriction digest patterns except for three strains of methylosinus trichosporium, which appeared to contain the same three plasmids. nitrocellulose filter hybridization revealed that the plasmid dna from the m. trichosporium strai ... | 1984 | 6442554 |
| phospholipid composition of methane-utilizing bacteria. | the phospholipids of methylococcus capsulatus, methylosinus trichosporium, la paz, and obt were examined in relation to their qualitative and quantitative composition. m. capsulatus exhibited a phospholipid composition consisting of phosphatidylethanolamine, phosphatidylglycerol, cardiolipin, and phosphatidyl-choline. the esterified fatty acids were predominantly c16:0 and c16:1. m. trichosporium, la paz, and obt exhibited an essentially identical phospholipid composition consisting of phosphati ... | 1978 | 96101 |
| microbial oxidation of gaseous hydrocarbons: epoxidation of c2 to c4 n-alkenes by methylotrophic bacteria. | over 20 new cultures of methane-utilizing microbes, including obligate (types i and iii) and facultative methylotrophic bacteria were isolated. in addition to their ability to oxidize methane to methanol, resting cell-suspensions of three distinct types of methane-grown bacteria (methylosinus trichosporium ob3b [type ii, obligate]; methylococcus capsulatus crl m1 nrrl b-11219 [type i, obligate]; and methylobacterium organophilum crl-26 nrrl b-11222 [facultative]) oxidize c2 to c4 n-alkenes to th ... | 1979 | 39502 |
| obligate methylotrophy: evaluation of dimethyl ether as a c1 compound. | the suitability of dimethyl ether as a c1 compound was examined with the obligate methylobacterium methylococcus capsulatus (texas). the ether did not support growth and was not formed during growth on methane; it was an inhibitor of growth and oxidation of methane and a poor oxidation substrate for cell suspensions. nadh stimulation of methane, but not dimethyl ether, oxidation occurred in cell extracts. | 1982 | 6802804 |
| 3-hexulose-6-phosphate synthase from methylomonas (methylococcus) capsulatus. | | 1982 | 6818422 |
| methyl sterol and cyclopropane fatty acid composition of methylococcus capsulatus grown at low oxygen tensions. | methylococcus capsulatus contained extensive intracytoplasmic membranes when grown in fed-batch cultures over a wide range of oxygen tensions (0.1 to 10.6%, vol/vol) and at a constant methane level. although the biomass decreased as oxygen levels were lowered, consistently high amounts of phospholipid and methyl sterol were synthesized. the greatest amounts of sterol and phospholipid were found in cells grown between 0.5 and 1.1% oxygen (7.2 and 203 mumol/g [dry weight], respectively). while ste ... | 1986 | 3087955 |
| steady-state kinetic analysis of soluble methane mono-oxygenase from methylococcus capsulatus (bath). | a steady-state kinetic analysis of purified soluble methane mono-oxygenase of methylococcus capsulatus (bath) was performed. the enzyme was found to follow a concerted-substitution mechanism. methane binds to the enzyme followed by nadh, which reacts to yield reduced enzyme and nad+. the reduced enzyme-methane complex binds o2 to give a second ternary complex, which breaks down to release water and methanol. in this way the enzyme can control the supply of electrons to the active site to coincid ... | 1986 | 3098230 |
| electron transfer reactions in the soluble methane monooxygenase of methylococcus capsulatus (bath). | aerobic stopped-flow experiments have confirmed that component c is the methane monooxygenase component responsible for interaction with nadh. reduction of component c by nadh is not the rate-limiting step for component c in the methane monooxygenase reaction. removal and reconstitution of the redox centres of component c suggest a correlation between the presence of the fad and fe2s2 redox centres and nadh: acceptor reductase activity and methane monooxygenase activity respectively, consistent ... | 1985 | 3918864 |
| particulate methane monooxygenase genes in methanotrophs. | a 45-kda membrane polypeptide that is associated with activity of the particulate methane monooxygenase (pmmo) has been purified from three methanotrophic bacteria, and the n-terminal amino acid sequence was found to be identical in 17 of 20 positions for all three polypeptides and identical in 14 of 20 positions for the n terminus of amob, the 43-kda subunit of ammonia monooxygenase. dna from a variety of methanotrophs was screened with two probes, an oligonucleotide designed from the n-termina ... | 1995 | 7768803 |
| sequence analysis of the gene cluster encoding toluene-3-monooxygenase from pseudomonas pickettii pko1. | the nucleotide (nt) sequence and gene organization of the locus encoding the initial step of the toluene-3-monooxygenase (tbu) pathway from pseudomonas pickettii pko1 has been determined. this is the first reported nt sequence for a toluene monooxygenase which hydroxylates the c-3 position of toluene. six tightly assembled structural genes encoding several tbu were identified and were designated tbua1, tbuu, tbub, tbuv, tbua2 and tbuc. comparison of the deduced amino acid (aa) sequences of each ... | 1995 | 7867951 |
| prokaryotic triterpenoids. 1. 3 beta-methylhopanoids from acetobacter species and methylococcus capsulatus. | 3 beta-methylbacteriohopanepolyol derivatives were isolated from three bacteria, acetobacter pasteurianus ssp. pasteurianus, methylococcus capsulatus and nostoc muscorum, and identified by spectroscopic methods and direct comparison with 3 beta-methyldiplopterol and 3 beta-methylhopan-29-ol synthesized from 22-hydroxyhopan-3-one. the 3 beta-methylhopanoid content of a. pasteurianus ssp. pasteurianus could be dramatically increased (up to 60% of the total hopanoid content) by addition of l-methio ... | 1985 | 3926494 |
| copper ions as inhibitors of protein c of soluble methane monooxygenase of methylococcus capsulatus (bath). | copper(i), copper(ii) and silver ions have been shown to be potent inhibitors of purified soluble methane monooxygenase (mmo) of methylococcus capsulatus (bath). a weaker inhibition has been observed with zinc and cadmium ions. proteins a and b of soluble mmo are unaffected by copper but protein c is rapidly and irreversibly inhibited. the site of copper inhibition has been shown to be primarily at the iron-sulphur centre of protein c with a secondary effect at the fad centre when the copper(ii) ... | 1985 | 3933977 |
| degradation of methyl bromide by methanotrophic bacteria in cell suspensions and soils. | cell suspensions of methylococcus capsulatus mineralized methyl bromide (mebr), as evidence by its removal from the gas phase, the quantitative recovery of br- in the spent medium, and the production of 14co2 from [14c]mebr. methyl fluoride fluoride (mef) inhibited oxidation of methane as well as that of [14c]mebr. the rate of mebr consumption by cells varied inversely with the supply of methane, which suggested a competitive relationship between these two substrates. however, mebr did not suppo ... | 1994 | 7986039 |
| protein b of soluble methane monooxygenase from methylococcus capsulatus (bath). a novel regulatory protein of enzyme activity. | an understanding of the mechanism of biological methane oxidation has been hampered by the lack of purified proteins. we describe here a purification protocol for the previously uncharacterized protein b of the soluble methane monooxygenase from the obligate methanotroph methylococcus capsulatus (bath). soluble methane monooxygenase is a multicomponent enzyme consisting of a hydroxylase component, protein a, a reductase component, protein c, and protein b. all three proteins are required for mon ... | 1985 | 3934164 |
| purification and properties of 3-hexulose phosphate synthase and phospho-3-hexuloisomerase from methylococcus capsulatus. | 3-hexulose phosphate synthase and phospho-3-hexuloisomerase were purified 40- and 150-fold respectively from methane-grown methylococcus capsulatus. the molecular weights of the enzymes were approximately 310000 and 67000 respectively, as determined by gel filtration. dissociation of 3-hexulose phosphate synthase into subunits of molecular weight approx. 49000 under conditions of low ph or low ionic strength was observed. within the range of compounds tested, 3-hexulose phosphate synthase is spe ... | 1974 | 4219834 |
| hexose phosphate synthase from methylcoccus capsulatus makes d-arabino-3-hexulose phosphate. | the product of the reaction catalysed by hexose phosphate synthase prepared from methylococcus capsulatus was dephosphorylated and the sugar moiety purified. the sugar and derivatives were compared by various chromatographic and other methods with authentic samples of allulose (psicose), d-erythro-l-glycero-3-hexulose and d-erythro-d-glycero-3-hexulose. the sugar is not allulose, as was previously thought on the basis of less extensive evidence (kemp & quayle, 1966), but is in fact d-erythro-l-g ... | 1974 | 4463938 |
| assimilation and toxicity of exogenous amino acids in the methane-oxidizing bacterium methylococcus capsulatus. | | 1972 | 4647472 |
| abduction of iron(iii) from the soluble methane monooxygenase hydroxylase and reconstitution of the binuclear site with iron and manganese. | the apo-form of the soluble methane monooxygenase hydroxylase from methylococcus capsulatus (bath) was prepared via chelation of iron(iii) with 3,4-dihydroxybenzaldehyde. the apohydroxylase was reconstituted by the anaerobic addition of fe(ii) followed by air oxidation. the enzyme thus prepared regained 85-90% of its original catalytic activity. the incorporation of two manganese(ii) ions/mol of apohydroxylase was monitored by epr spectroscopy. the mn(ii) ions occupy the native diiron active sit ... | 1993 | 8223558 |
| quantitative aspects of growth of the methane oxidizing bacterium methylococcus capsulatus on methane in shake flask and continuous chemostat culture. | | 1972 | 4651256 |
| assimilation and toxicity of some exogenous c1 compounds, alcohols, sugars and acetate in the methane-oxidizing bacterium methylococcus capsulatus. | | 1973 | 4722562 |
| physiological studies of methane- and methanol-oxidizing bacteria: comparison of a primary alcohol dehydrogenase from methylococcus capsulatus (texas strain) and pseudomonas species m27. | a primary alcohol dehydrogenase has been purified from methylococcus capsulatus (texas strain). the purified enzyme catalyzes the oxidation of methanol and formaldehyde to formate; other primary alcohols are oxidized to their corresponding aldehydes. ammonium ions are required for enzyme activity. the enzyme has a molecular weight of 120,000 daltons and consists of two 62,000 molecular-weight subunits which dissociate at acidic ph. the enzyme is similar to an alcohol dehydrogenase enzyme isolate ... | 1972 | 5022170 |
| mutation of the methane oxidizing bacterium methylococcus capsulatus. | | 1972 | 5025436 |
| the hexose phosphate synthetase of methylococcus capsulatus. | | 1972 | 5076210 |
| pteridines produced by methylococcus capsulatus. isolation and identification of a neopterin 2':3'-phosphate. | three pteridines have been isolated from the methane- or methanol-oxidizing bacterium methylococcus capsulatus. two of these are known compounds, 2-amino-6-carboxy-4-hydroxypteridine and 2-amino-4-hydroxy-6-methylpteridine. the third is shown by degradative and synthetic experiments to be l-threo-neopterin 2':3'-phosphate. labelling experiments show that both the pteridine moiety and phosphate residue are derived from a single gtp molecule. the possible metabolic significance of these compounds ... | 1971 | 5158900 |
| cleavage of malyl-coenzyme a into acetyl-coenzyme a and glyoxylate by pseudomonas am1 and other c1-unit-utilizing bacteria. | 1. malyl-coa lyase was found in high activity in extracts of pseudomonas am1, pseudomonas ma, pseudomonas ms, hyphomicrobium x and methylosinus trichosporium. 2. the enzyme cleaves (2s)-malyl-coa into equimolar amounts of acetyl-coa and glyoxylate in the presence of mg(2+). 3. the specific activity of malyl-coa lyase was several-fold higher in pseudomonas am1 when grown on c(1) compounds than when grown on c(2), c(3) or c(4) compounds. this suggests that the enzyme plays a specially important ro ... | 1973 | 4772632 |
| molecular genetics of methane oxidation. | biological methane oxidation is carried out by methanotrophs, bacteria that utilize methane as their sole carbon and energy source. the enzyme they contain that is responsible for methane oxidation is methane monooxygenase, the most well studied being the soluble methane monooxygenase enzyme complexes from methylococcus capsulatus (bath) and methylosinus trichosporium ob3b. in both organisms, the genes encoding soluble methane monooxygenase have been found to be clustered on the chromosome in th ... | 1994 | 7765830 |
| oxidation of hydroxylamine by cytochrome p-460 of the obligate methylotroph methylococcus capsulatus bath. | an enzyme capable of the oxidation of hydroxylamine to nitrite was isolated from the obligate methylotroph methylococcus capsulatus bath. the absorption spectra in cell extracts, electron paramagnetic resonance spectra, molecular weight, covalent attachment of heme group to polypeptide, and enzymatic activities suggest that the enzyme is similar to cytochrome p-460, a novel iron-containing protein previously observed only in nitrosomonas europaea. the native and subunit molecular masses of the m ... | 1994 | 7928947 |
| genetics of methane and methanol oxidation in gram-negative methylotrophic bacteria. | within the past few years, considerable progress has been made in the understanding of the molecular genetics of methane and methanol oxidation. in order to summarize this progress and to illustrate the important genetic methods employed, this review will focus on several well-studied organisms. these organisms include the gram-negative faculative methylotrophs methylobacterium extorquens, methylobacterium organophilum and paracoccus denitrificans. in addition, the obligate methanotrophs methylo ... | 1993 | 8092853 |
| the nature of the copper ions in the membranes containing the particulate methane monooxygenase from methylococcus capsulatus (bath). | it is shown that the particulate methane monooxygenase (pmmo) has an obligate requirement for copper. the mmo activity in the particulate fractions obtained from methylococcus capsulatus (bath) cells is found to increase with increasing copper content of the membranes. the enzyme activity from membranes obtained from cells grown at low copper levels can be stimulated further by the addition of cu(ii) ions to the assay medium. the membrane-bound copper ions can exist in both cu(ii) and cu(i) form ... | 1994 | 8195135 |
| outer membrane proteins of methylococcus capsulatus (bath). | membranes obtained from whole-cell lysates of methylococcus capsulatus (bath) were separated by triton x-100 extraction. the resulting insoluble fraction was enriched in outer membranes as assessed by electron microscopy and by the content of beta-hydroxy palmitic acid and particulate methane monooxygenase. major proteins with molecular masses of approximately 27, 40, 46, 59, and 66 kda were detected by sds-page of the triton-x-100-insoluble membranes. mopa, mopb, mopc, mopd, and mope (methyloco ... | 1997 | 9238104 |
| nuclear hyperfine coupling of nitrogen in the coordination sphere of the diiron center of methane monooxygenase hydroxylase. | electron spin echo envelope modulation spectroscopy identified two ligand 14n interactions with the mixed-valence, fe(ii/iii) diiron center of methane monooxygenase hydroxylase from methylococcus capsulatus (bath). characteristic features of the spectra obtained at 9 and 10 ghz were analyzed and fit by simulation. one of the nitrogens possessed superhyperfine parameters (aiso = 0.8 mhz, reff = 3.2 a, e2qq = 1.8 mhz, eta = 0.35) consistent with a non-coordinating amino nitrogen of a histidine imi ... | 1994 | 8206895 |
| crystal structure of a bacterial non-haem iron hydroxylase that catalyses the biological oxidation of methane. | the 2.2 a crystal structure of the 251k alpha 2 beta 2 gamma 2 dimeric hydroxylase protein of methane monooxygenase from methylococcus capsulatus (bath) reveals the geometry of the catalytic di-iron core. the two iron atoms are bridged by exogenous hydroxide and acetate ligands and further coordinated by four glutamate residues, two histidine residues and a water molecule. the dinuclear iron centre lies in a hydrophobic active-site cavity for binding methane. an extended canyon runs between alph ... | 1993 | 8255292 |
| activation of the hydroxylase of smmo from methylococcus capsulatus (bath) by hydrogen peroxide. | hydrogen peroxide can activate the non-heme binuclear iron-containing hydroxylase of soluble methane monooxygenase (smmo) from methylococcus capsulatus (bath) in the catalysis of oxidation of methane and other smmo substrates. the reductase, protein b, o2 and nadh are normally required for catalytic activity, but can be replaced by h2o2 serving as the source of both oxygen and electrons for the reaction. similar results have been observed in a different strain of mmo from methylosinus trichospor ... | 1993 | 8476925 |
| membrane-associated methane monooxygenase from methylococcus capsulatus (bath). | an active preparation of the membrane-associated methane monooxygenase (pmmo) from methylococcus capsulatus bath was isolated by ion-exchange and hydrophobic interaction chromatography using dodecyl beta-d-maltoside as the detergent. the active preparation consisted of three major polypeptides with molecular masses of 47,000, 27,000, and 25,000 da. two of the three polypeptides (those with molecular masses of 47,000 and 27,000 da) were identified as the polypeptides induced when cells expressing ... | 1996 | 8576034 |
| the purification of ammonia monooxygenase from paracoccus denitrificans. | the heterotrophic nitrifier paracoccus denitrificans expresses a membrane-associated ammonia monooxygenase. the active enzyme has been solubilized in the detergent dodecyl-beta-d-maltoside and purified by standard chromatographic techniques. this is the first purification of an ammonia monooxygenase. the enzyme consists of two subunits with molecular masses of 38 and 46 kda. the purified enzyme is a quinol oxidase, is inhibited by light and a variety of chelating agents and is activated by cupri ... | 1996 | 8654570 |
| analysis of 16s rrna and methane monooxygenase gene sequences reveals a novel group of thermotolerant and thermophilic methanotrophs, methylocaldum gen. nov. | two methanotrophic bacteria with optimum growth temperatures above 40 degrees c were isolated. thermotolerant strain lk6 was isolated from agricultural soil, and the moderately thermophilic strain or2 was isolated from the effluent of an underground hot spring. when compared to the described thermophilic methanotrophs methylococcus capsulatus and methylococcus thermophilus, these strains are phenotypically similar to methylococcus thermophilus. however, their 16s rrna gene sequences are markedly ... | 1997 | 9385141 |
| geometry of the soluble methane monooxygenase catalytic diiron center in two oxidation states. | the hydroxylase component of soluble methane monooxygenase (smmo) contains a dinuclear iron center responsible for the oxidation of methane to methanol. as isolated, the center is in the oxidized, diiron(iii) state. the 2.2 a resolution x-ray structure of the oxidized hydroxylase, hox, from methylococcus capsulatus (bath) was previously determined at 4 degrees c. in this structure the two iron atoms are bridged by a glutamate, a hydroxide ion, and an acetate ion, and additionally coordinated to ... | 1995 | 9432288 |
| synthesis of cell constituents by methane-grown methylococcus capsulatus and methanomonas methanooxidans. | 1. a study was made of the incorporation of carbon from [(14)c]methanol by cultures of methylococcus capsulatus and methanomonas methanooxidans growing on methane. 2. the distribution of radioactivity within the non-volatile constituents of the ethanol-soluble fractions of the cells, after incubation with labelled substrate for periods of up to 3min, was analysed by chromatography and radioautography. 3. over 80% of the radioactivity fixed by methylococcus capsulatus at 30 degrees c at the earli ... | 1970 | 5435492 |
| influence of amino acids, carboxylic acids and sugars on the growth of methylococcus capsulatus on methane. | | 1968 | 5702043 |
| a methane-dependent coccus, with notes on classification and nomenclature of obligate, methane-utilizing bacteria. | foster, j. w. (the university of texas, austin), and richard h. davis. a methane-dependent coccus, with notes on classification and nomenclature of obligate, methane-utilizing bacteria. j. bacteriol. 91:1924-1931. 1966.-a new coccus-shaped bacterium capable of aerobic growth at the expense of methane or methanol in a mineral salts medium is described. the organism did not grow at the expense of any of the conventional substrates or homologous hydrocarbons tested. it is gram-negative, nonmotile, ... | 1966 | 5937247 |
| [role of co-binding cytochrome c in enzymatic oxidation of methane by the bacterium methylococcus capsulatus]. | the cytochrome c spectrally related to cco cytochromes has been isolated and purified from the methane-oxidizing bacterium methylococcus capsulatus. the cytochrome binds co but does not bind other substrates of methane monooxygenase, does not activate the methane monooxygenase reaction and is not a component of methane monooxygenase. in the methanol dehydrogenase enzymatic system cytochrome cco functions as electron acceptor. a possible role of cytochrome cco as electron carrier intermediate in ... | 1982 | 6288124 |
| purification and characterization of component a of the methane monooxygenase from methylococcus capsulatus (bath). | methylococcus capsulatus (bath) possesses a multi-component methane monooxygenase which catalyzes in vivo the conversion of methane to methanol. component a of this enzyme system, believed to be the oxygenase component, has been purified to near homogeneity (95%). the native protein has a molecular weight of approximately 210,000 and is comprised of three subunits of mr = 54,000, 42,000, and 17,000, which appear to be present in stoichiometric amounts suggesting an alpha 2, beta 2, gamma 2 arran ... | 1984 | 6323414 |
| purification of component a of the soluble methane monooxygenase of methylococcus capsulatus (bath) by high-pressure gel permeation chromatography. | a major improvement in the purification of the oxygenase protein (component a) of the methane monooxygenase has been effected. by employing high-pressure gel permeation chromatography several purification steps may be omitted from the previously published scheme. furthermore the yield of the protein is enhanced and more importantly the recovered protein displays an increased specific activity, unlike that purified by other techniques. | 1984 | 6433743 |
| non-specific lanosterol and hopanoid biosynthesis be a cell-free system from the bacterium methylococcus capsulatus. | 1. a cell-free system from the bacterium methylococcus capsulatus was incubated with [12-3h]-squalene; diploptene and diplopterol, normally present in the bacterium, were labelled. 2 the same cell-free system was incubated with (rs)-2,3-epoxy-2,3-dihydro-[3-3h]squalene. several radioactive 3-hydroxytriterpenes were purifed. lanosterol, which is normally present in this bacterium, was found labelled as well as 3-epilanosterol. in addition, radioactive 3 alpha-hydroxy and 3 beta-hydroxydiploptene ... | 1980 | 6780348 |
| helicobacter pylori glutamine synthetase lacks features associated with transcriptional and posttranslational regulation. | helicobacter pylori urease, produced in abundance, is indispensable for the survival of h. pylori in animal hosts. urea is hydrolyzed by the enzyme, resulting in the liberation of excess ammonia, some of which neutralizes gastric acid. the remaining ammonia is assimilated into protein by glutamine synthetase (ec 6.3.1.2), which catalyzes the reaction: nh3 + glutamate + atp-->glutamine + adp + pi. we hypothesized that glutamine synthetase plays an unusually critical role in nitrogen assimilation ... | 1998 | 9573059 |
| a highly selective pcr protocol for detecting 16s rrna genes of the genus pseudomonas (sensu stricto) in environmental samples. | pseudomonas species are plant, animal, and human pathogens; exhibit plant pathogen-suppressing properties useful in biological control; or express metabolic versatilities valued in biotechnology and bioremediation. specific detection of pseudomonas species in the environment may help us gain a more complete understanding of the ecological significance of these microorganisms. the objective of this study was to develop a pcr protocol for selective detection of pseudomonas (sensu stricto) in envir ... | 1998 | 9647828 |
| microbial oxidation of gaseous hydrocarbons: production of alcohols and methyl ketones from their corresponding n-alkanes by methylotrophic bacteria. | cell suspensions of methane-utilizing bacteria oxidized n-alkanes (propane, butane, pentane, and hexane) to their corresponding alcohols and methyl ketones. the product alcohols and methyl ketones accumulated extracellularly. methanol-grown cells of methane-utilizing bacteria did not oxidize n-alkanes. the product primary alcohol was detected in a cell-free system but only in a trace amount in the whole cell system due to further oxidation. the optimum conditions for in vivo formation of seconda ... | 1981 | 6783282 |
| heat-tolerant methanotrophic bacteria from the hot water effluent of a natural gas field. | methanotrophic bacteria were isolated from a natural environment potentially favorable to heat-tolerant methanotrophs. an improved colony plate assay was developed and used to identify putative methanotrophic colonies with high confidence. fourteen new isolates were purified and partially characterized. these new isolates exhibit a dna sequence homology of up to 97% with the conserved regions in the mmox and mmoc genes of the soluble methane monooxygenase (mmo)-coding gene cluster of methylococc ... | 1995 | 7486989 |
| effect of nitrogen source on growth and trichloroethylene degradation by methane-oxidizing bacteria. | the effect of nitrogen source on methane-oxidizing bacteria with respect to cellular growth and trichloroethylene (tce) degradation ability were examined. one mixed chemostat culture and two pure type ii methane-oxidizing strains, methylosinus trichosporium ob3b and strain cac-2, which was isolated from the chemostat culture, were used in this study. all cultures were able to grow with each of three different nitrogen sources: ammonia, nitrate, and molecular nitrogen. both m. trichosporium ob3b ... | 1998 | 9726896 |
| pseudomonas sp. strain 273, an aerobic alpha, omega-dichloroalkanedegrading bacterium. | a gram-negative, aerobic bacterium was isolated from soil; this bacterium grew in 50% (vol/vol) suspensions of 1,10-dichlorodecane (1,10-dcd) as the sole source of carbon and energy. phenotypic and small-subunit ribosomal rna characterizations identified the organism, designated strain 273, as a member of the genus pseudomonas. after induction with 1,10-dcd, pseudomonas sp. strain 273 released stoichiometric amounts of chloride from c5 to c12 alpha, omega-dichloroalkanes in the presence of oxyge ... | 1998 | 9726906 |
| the role of copper in the pmmo of methylococcus capsulatus bath: a structural vs. catalytic function. | methanotrophs convert methane to methanol by the methane monooxygenase (mmo). it is well known that two forms of the mmo can be expressed: one form is found in the cytoplasm, or in the soluble fraction (smmo); the other is associated with the membranes, or particulate fraction (pmmo). the smmo has been extensively examined, and much is known about its structure and mechanism of dioxygen activation. the pmmo, however, is less well understood: the enzyme has proven difficult to purify as it loses ... | 1995 | 7500086 |
| evidence for an iron center in the ammonia monooxygenase from nitrosomonas europaea. | binding of the ligand, nitric oxide, in the presence of reductant was used to identify a ferrous s = 3/2 signal, characteristic of a ferrous nitrosyl complex, and a g= 2.03 copper or iron signal in membranes of the ammonia-oxidizing bacterium, nitrosomonas europaea. the same ferrous s = 3/2 signal is thought to be a component of the membrane-associated methane monooxygenase (pmmo) of methylococcus capsulatus bath, since it is seen in the membrane fraction of cells expressing pmmo and in the puri ... | 1996 | 8941709 |
| detection of methanotrophic bacteria in environmental samples with the pcr. | we designed pcr primers by using the dna sequences of the soluble methane monooxygenase gene clusters of methylosinus trichosporium ob3b and methylococcus capsulatus (bath), and these primers were found to be specific for four of the five structural genes in the soluble methane monooxygenase gene clusters of several methanotrophs. we also designed primers for the gram-negative methylotroph-specific methanol dehydrogenase gene moxf. the specificity of these primers was confirmed by hybridizing an ... | 1995 | 7887594 |
| difluoromethane, a new and improved inhibitor of methanotrophy | difluoromethane (hfc-32; dfm) is compared to acetylene and methyl fluoride as an inhibitor of methanotrophy in cultures and soils. dfm was found to be a reversible inhibitor of ch4 oxidation by methylococcus capsulatus (bath). consumption of ch4 in soil was blocked by additions of low levels of dfm (0.03 kpa), and this inhibition was reversed by dfm removal. although a small quantity of dfm was consumed during these incubations, its remaining concentration was sufficiently elevated to sustain in ... | 1998 | 9797290 |
| crystal structure of the hydroxylase component of methane monooxygenase from methylosinus trichosporium ob3b. | methane monooxygenase (mmo), found in aerobic methanotrophic bacteria, catalyzes the o2-dependent conversion of methane to methanol. the soluble form of the enzyme (smmo) consists of three components: a reductase, a regulatory "b" component (mmob), and a hydroxylase component (mmoh), which contains a hydroxo-bridged dinuclear iron cluster. two genera of methanotrophs, termed type x and type ii, which differ markedly in cellular and metabolic characteristics, are known to produce the smmo. the st ... | 1997 | 9070438 |