Publications

structure of methylosinus trichosporium exospores.	methylosinus trichosporium exospores did not display a well-defined cortex or an exosporium. a thick, electron-dense exospore wall was characteristic of the exospores. located on the exterior of the exospore wall was a cell wall to which a well-defined capsule was attached. an extensive lamellar intracytoplasmic membrane system characteristic of the kind in vegetative cells of this bacterium was present along the interior periphery of the exospore wall. upon germination of m. trichosporium exosp ...	1980	6767693
bacteriophages of methanotrophic bacteria.	bacteriophages of methanotrophic bacteria have been found in 16 out of 88 studied samples (underground waters, pond water, soil, gas and oil installation waters, fermentor cultural fluids, bacterial paste, and rumen of cattle) taken in different geographic zones of the soviet union. altogether, 23 phage strains were isolated: 10 strains that specifically lysed only methylosinus sporium strains, 2 strains that each lysed 1 of 5 methylosinus trichosporium strains studied, and 11 strains that lysed ...	1980	6774962
microbial oxidation of gaseous hydrocarbons: production of methylketones from corresponding n-alkanes by methane-utilizing bacteria.	cell suspensions of methane-utilizing bacteria grown on methane oxidized n-alkanes (propane, butane, pentane, hexane) to their corresponding methylketones (acetone, 2-butanone, 2-pentanone, 2-hexanone). the product methylketones accumulated extracellularly. the rate of production of methylketones varied with the organism used for oxidation; however, the average rate of acetone, 2-butanone, 2-pentanone, and 2-hexanone production was 1.2, 1.0, 0.15, and 0.025 mumol/h per 5.0 mg of protein in cell ...	1980	16345538
exospore formation in methylosinus trichosporium.	formation of exospores in methylosinus trichosporium was examined by electron microscopy; serial sectioning was used to visualize the shape and location of the developing exospore in relation to the vegetative cell. the initial stage was the formation of a budlike enlargement on one end of the vegetative cell. the enlargement was surrounded by the exospore capsule, and the cell wall was continuous around both the cell and the developing exospore. a constriction occurred in the area where the bud ...	1982	7054146
effects of nitrapyrin [2-chloro-6-(trichloromethyl) pyridine] on the obligate methanotroph methylosinus trichosporium ob3b.	nitrapyrin inhibited growth, ch(4) oxidation, and nh(4) oxidation, but not the oxidation of ch(3)oh, hcho, or hcoona, by methylosinus trichosporium ob3b, suggesting that nitrapyrin acts against the methane monooxygenase enzyme system. the inhibition of ch(4) oxidation could be reversed by repeated washing of nitrapyrin-inhibited cells, indicating that its effect is bacteriostatic. the addition of cu did not release the inhibition. methane oxidation was also inhibited by 6-chloro-2-picoline. thes ...	1984	16346465
effects of nitrapyrin [2-chloro-6-(trichloromethyl) pyridine] on the obligate methanotroph methylosinus trichosporium ob3b.	[this corrects the article on p. 261 in vol. 47.].	1985	16346799
comparison of bacterial lipopolysaccharides by high-performance liquid chromatography.	a comparison of lipid-free polysaccharides from gram-negative bacteria was rapidly accomplished by using high-performance liquid chromatography of underivatized hydrolysates. examination of a number of such products revealed that, contrary to earlier reports, xanthomonas campestris lipopolysaccharide contained heptose, together with rhamnose and galactose, but not mannose. the polymers from the methanotrophs "methylomonas albus" and "methylosinus trichosporium" contained heptose and glucose, and ...	1986	16347189
regulation of two nickel-requiring (inducible and constitutive) hydrogenases and their coupling to nitrogenase in methylosinus trichosporium ob3b.	two uptake hydrogenases were found in the obligate methanotroph methylosinus trichosporium ob3b; one was constitutive, and a second was induced by h2. both hydrogenases could be assayed by measuring methylene blue reduction anaerobically or by coupling their activity to nitrogenase acetylene reduction activity in vivo in an o2-dependent reaction. the h2 concentration for half-maximal activity of the inducible and constitutive hydrogenases in both assays was 0.01 and 0.5 bar (1 and 50 kpa), respe ...	1987	3115963
degradation of trichloroethylene by toluene dioxygenase in whole-cell studies with pseudomonas putida f1.	toluene-induced cells of pseudomonas putida f1 removed trichloroethylene from growth media at a significantly greater initial rate than the methanotroph methylosinus trichosporium ob3b. with toluene-induced p. putida f1, the initial degradation rate varied linearly with trichloroethylene concentration over the range of 8 to 80 microm (1.05 to 10.5 ppm). at 80 microm (10.5 ppm) trichloroethylene and 30 degrees c, the initial rate was 1.8 nmol/min per mg of total cell protein, but the rate decreas ...	1988	3415234
biodegradation of trichloroethylene by methylosinus trichosporium ob3b.	the methanotroph methylosinus trichosporium ob3b, a type ii methanotroph, degraded trichloroethylene at rates exceeding 1.2 mmol/h per g (dry weight) following the appearance of soluble methane monooxygenase in continuous and batch cultures. cells capable oxidizing trichloroethylene contained components of soluble methane monooxygenase as demonstrated by western blot (immunoblot) analysis with antibodies prepared against the purified enzyme. growth of cultures in a medium containing 0.25 microm ...	1989	2515801
degradation of chlorinated aliphatic hydrocarbons by methylosinus trichosporium ob3b expressing soluble methane monooxygenase.	degradation of trichloroethylene (tce) by the methanotrophic bacterium methylosinus trichosporium ob3b was studied by using cells grown in continuous culture. tce degradation was a strictly cometabolic process, requiring the presence of a cosubstrate, preferably formate, and oxygen. m. trichosporium ob3b cells degraded tce only when grown under copper limitation and when the soluble methane monooxygenase was derepressed. during tce degradation, nearly total dechlorination occurred, as indicated ...	1989	2624462
isolation, characterization, and biological activity of ferredoxin-nad+ reductase from the methane oxidizer methylosinus trichosporium ob3b.	a ferredoxin-nad+ oxidoreductase (ec 1.18.1.3) has been isolated from extracts of the obligate methanotroph methylosinus trichosporium ob3b. this enzyme was shown to couple electron flow from formate dehydrogenase (nad+ requiring) to ferredoxin. ferredoxin-nad+ reductase was purified to homogeneity by conventional chromatography techniques and was shown to be a flavoprotein with a molecular weight of 36,000 +/- 1,000. this ferredoxin reductase was specific for nadh (km, 125 microm) and coupled e ...	1989	2768195
oxidation of aromatic alcohols by purified methanol dehydrogenase from methylosinus trichosporium.	methanol dehydrogenase was found to be present in subcellular preparations of methanol-grown methylosinus trichosporium and occurred almost wholly in the soluble fraction of the cell. the enzyme, purified by deae-sephadex and sephadex g-100 chromatography, showed broad specificity toward different substrates and oxidized the aromatic alcohols benzyl, vanillyl, and veratryl alcohols in addition to a range of aliphatic primary alcohols. no enzyme activity was found toward the corresponding aldehyd ...	1990	2193913
formate dehydrogenase from the methane oxidizer methylosinus trichosporium ob3b.	formate dehydrogenase (nad+ dependent) was isolated from the obligate methanotroph methylosinus trichosporium ob3b. when the enzyme was isolated anaerobically, two forms of the enzyme were seen on native polyacrylamide gels, de-52 cellulose and sephacryl s-300 columns; they were approximately 315,000 and 155,000 daltons. the enzyme showed two subunits on sodium dodecyl sulfate-polyacrylamide gels. the mr of the alpha-subunit was 53,800 +/- 2,800, and that of the beta-subunit was 102,600 +/- 3,90 ...	1990	2376564
oxidation of lignin-related aromatic alcohols by cell suspensions of methylosinus trichosporium.	cell suspensions of methylosinus trichosporium oxidized the aromatic alcohols benzyl alcohol, vanillyl alcohol, and veratryl alcohol to the corresponding aldehydes, and with the exception of vanillyl alcohol, the aldehydes were further oxidized to the corresponding aromatic acids. no other transformation was observed, and the methoxyl moieties attached to the aromatic nucleus remained intact. more than 70% of the alcohol oxidized could be accounted for by aldehyde and/or acid. investigation of t ...	1990	16348098
fate of 2,2,2-trichloroacetaldehyde (chloral hydrate) produced during trichloroethylene oxidation by methanotrophs.	four different methanotrophs expressing soluble methane monooxygenase produced 2,2,2-trichloroacetaldehyde, or chloral hydrate, a controlled substance, during the oxidation of trichloroethylene. chloral hydrate concentrations decreased in these cultures between 1 h and 24 h of incubation. chloral hydrate was shown to be biologically transformed to trichloroethanol and trichloroacetic acid by methylosinus trichosporium ob3b. at elevated ph and temperature, chloral hydrate readily decomposed and c ...	1991	1768109
kinetics of chlorinated hydrocarbon degradation by methylosinus trichosporium ob3b and toxicity of trichloroethylene.	the kinetics of the degradation of trichloroethylene (tce) and seven other chlorinated aliphatic hydrocarbons by methylosinus trichosporium ob3b were studied. all experiments were performed with cells grown under copper stress and thus expressing soluble methane monooxygenase. compounds that were readily degraded included chloroform, trans-1,2-dichloroethylene, and tce, with vmax values of 550, 330, and 290 nmol min-1 mg of cells-1, respectively. 1,1-dichloroethylene was a very poor substrate. t ...	1991	2036023
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
characterization of a methane-utilizing bacterium from a bacterial consortium that rapidly degrades trichloroethylene and chloroform.	a mixed culture of bacteria grown in a bioreactor with methane as a carbon and energy source rapidly oxidized trichloroethylene and chloroform. the most abundant organism was a crescent-shaped bacterium that bound the fluorescent oligonucleotide signature probes that specifically hybridize to serine pathway methylotrophs. the 5s rrna from this bacterium was found to be 93.5% homologous to the methylosinus trichosporium ob3b 5s rna sequence. a type ii methanotrophic bacterium, isolated in pure cu ...	1992	1377902
hydrodynamic effects on microcapillary motility and chemotaxis assays of methylosinus trichosporium ob3b.	a study of the random motility and chemotaxis of methylosinus trichosporium ob3b was conducted by using palleroni-chamber microcapillary assay procedures. under the growth conditions employed, this methanotroph was observed qualitatively with a microscope to be either slightly motile or essentially nonmotile. however, the cells did not not respond in the microcapillary assays in the manner expected for nonmotile brownian particles. as a consequence, several hydrodynamic effects on these palleron ...	1992	1444383
applications of a colorimetric plate assay for soluble methane monooxygenase activity.	a straightforward method is described for screening methanotrophic colonies for soluble methane monooxygenase (smmo) activity on solid media. such activity results in the development of a colored complex between 1-naphthol, which is formed when smmo reacts with naphthalene, and o-dianisidine (tetrazotized). methanotrophic colonies expressing smmo turned deep purple when exposed successively to naphthalene and o-dianisidine. the method was evaluated within the contexts of two potential applicatio ...	1992	1637160
methylosinus trichosporium ob3b mutants having constitutive expression of soluble methane monooxygenase in the presence of high levels of copper.	the methanotrophic bacterium methylosinus trichosporium ob3b is unusually active in degrading recalcitrant haloalkanes such as trichloroethylene (tce). the first and rate-limiting step in the degradation of tce is catalyzed by a soluble methane monooxygenase (smmo). this enzyme is not expressed when the cells are grown in the presence of copper at concentrations typically found in polluted groundwater. under these conditions, m. trichosporium ob3b expresses a particulate form of the enzyme (pmmo ...	1992	16348810
soluble methane monooxygenase production and trichloroethylene degradation by a type i methanotroph, methylomonas methanica 68-1.	a methanotroph (strain 68-1), originally isolated from a trichloroethylene (tce)-contaminated aquifer, was identified as the type i methanotroph methylomonas methanica on the basis of intracytoplasmic membrane ultrastructure, phospholipid fatty acid profile, and 16s rrna signature probe hybridization. strain 68-1 was found to oxidize naphthalene and tce via a soluble methane monooxygenase (smmo) and thus becomes the first type i methanotroph known to be able to produce this enzyme. the specific ...	1993	16348920
application of a tetrazolium salt with a water-soluble formazan as an indicator of viability in respiring bacteria.	the tetrazolium salt sodium 3'-{1-[(phenylamino)-carbonyl]-3,4-tetrazolium}-bis (4-methoxy-6-nitro)benzene-sulfonic acid hydrate (xtt) was examined for use as a colorimetric indicator of viability in respiring bacteria. xtt was reduced to an orange, water-soluble formazan product by methylosinus trichosporium ob3b, pseudomonas putida, escherichia coli, and bacillus subtilis. formazan production was proportional to live cell biomass, and xtt was reduced by all cultures in the absence of added ele ...	1993	16349038
phenotypic characterization of copper-resistant mutants of methylosinus trichosporium ob3b.	cultures of methylosinus trichosporium ob3b grown in the presence of very low concentrations of copper synthesize a soluble methane monooxygenase (smmo) that efficiently catalyzes the oxidation of trichloroethylene and other organic pollutants. recently, we isolated five m. trichosporium ob3b mutants that express smmo activity when grown in the presence of elevated copper concentrations (p.a. phelps, s. k. agarwal, g. e. speitel, jr., and g. georgiou, appl. environ. microbiol. 58:3701-3708, 1992 ...	1993	8215352
characterization of the methanotrophic bacterial community present in a trichloroethylene-contaminated subsurface groundwater site.	groundwater, contaminated with trichloroethylene (tce) and tetrachloroethylene (pce), was collected from 13 monitoring wells at area m on the u.s. department of energy savannah river site near aiken, s.c. filtered groundwater samples were enriched with methane, leading to the isolation of 25 methanotrophic isolates. the phospholipid fatty acid profiles of all the isolates were dominated by 18:1 omega 8c (60 to 80%), a signature lipid for group ii methanotrophs. subsequent phenotypic testing show ...	1993	8368829
survival and recovery of methanotrophic bacteria starved under oxic and anoxic conditions.	the effects of carbon deprivation on survival of methanotrophic bacteria were compared in cultures incubated in the presence and absence of oxygen in the starvation medium. survival and recovery of the examined methanotrophs were generally highest for cultures starved under anoxic conditions as indicated by poststarvation measurements of methane oxidation, tetrazolium salt reduction, plate counts, and protein synthesis. methylosinus trichosporium ob3b survived up to 6 weeks of carbon deprivation ...	1994	16349336
methanotrophic bacteria and facilitated transport of pollutants in aquifer material.	in situ stimulation of methanotrophic bacteria has been considered as a methodology for aquifer remediation. chlorinated aliphatic hydrocarbons such as trichloroethylene are fortuitously oxidized by the methane monooxygenase produced by methanotrophic bacteria. experimental results are presented that indicate that both colloidal suspensions containing methanotrophic cells and the soluble extracellular polymers produced by methanotrophic cells have the potential to enhance the transport and remov ...	1994	16349401
ammonium and nitrite inhibition of methane oxidation by methylobacter albus bg8 and methylosinus trichosporium ob3b at low methane concentrations.	methane oxidation by pure cultures of the methanotrophs methylobacter albus bg8 and methylosinus trichosporium ob3b was inhibited by ammonium choride and sodium nitrite relative to that in cultures assayed in either nitrate-containing or nitrate-free medium. m. albus was generally more sensitive to ammonium and nitrite than m. trichosporium. both species produced nitrite from ammonium; the concentrations of nitrite produced increased with increasing methane concentrations in the culture headspac ...	1994	16349402
cometabolic degradation of trichloroethylene by pseudomonas cepacia g4 in a chemostat with toluene as the primary substrate.	pseudomonas cepacia g4 is capable of cometabolic degradation of trichloroethylene (tce) if the organism is grown on certain aromatic compounds. to obtain more insight into the kinetics of tce degradation and the effect of tce transformation products, we have investigated the simultaneous conversion of toluene and tce in steady-state continuous culture. the organism was grown in a chemostat with toluene as the carbon and energy source at a range of volumetric tce loading rates, up to 330 mumol/li ...	1994	7524444
trichloroethylene and chloroform degradation by a recombinant pseudomonad expressing soluble methane monooxygenase from methylosinus trichosporium ob3b.	soluble methane monooxygenase (smmo) from methylosinus trichosporium ob3b can degrade many halogenated aliphatic compounds that are found in contaminated soil and groundwater. this enzyme oxidizes the most frequently detected pollutant, trichloroethylene (tce), at least 50 times faster than other enzymes. however, slow growth of the strain, strong competition between tce and methane for smmo, and repression of the smmo locus by low concentrations of copper ions limit the use of this bacterium. t ...	1994	8074526
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
aerobic and anaerobic starvation metabolism in methanotrophic bacteria.	the capacity for anaerobic metabolism of endogenous and selected exogenous substrates in carbon- and energy-starved methanotrophic bacteria was examined. the methanotrophic isolate strain wp 12 survived extended starvation under anoxic conditions while metabolizing 10-fold less endogenous substrate than did parallel cultures starved under oxic conditions. during aerobic starvation, the cell biomass decreased by 25% and protein and lipids were the preferred endogenous substrates. aerobic protein ...	1995	16535004
differential inhibition by allylsulfide of nitrification and methane oxidation in freshwater sediment.	addition of nitrapyrin, allylthiourea, c(inf2)h(inf2), and ch(inf3)f to freshwater sediment slurries inhibited ch(inf4) oxidation and nitrification to similar extents. dicyandiamide and allylsulfide were less inhibitory for ch(inf4) oxidation than for nitrification. allylsulfide was the most potent inhibitor of nitrification, and the estimated 50% inhibitory concentrations for this process and ch(inf4) oxidation were 0.2 and 121 (mu)m, respectively. at a concentration of 2 (mu)m allylsulfide, gr ...	1995	16535183
degradation of trichloroethylene by methanol-grown cultures of methylosinus trichosporium ob3b pp358.	a soluble methane monooxygenase-constitutive mutant strain of methylosinus trichosporium ob3b, strain pp358, was grown with methanol as the carbon source, and the kinetics of trichloroethylene (tce) degradation were determined. pp358 exhibited high tce degradation rates under both oxygen- and carbon-limiting conditions. the optimal pseudo first-order rate constant for tce was comparable to the values measured for cells grown with methane. we found that growth under oxygen-limiting conditions res ...	1996	16535263
responses of methanotrophic activity in soils and cultures to water stress.	diffusive gas transport at high water contents and physiological water stress at low water contents limited atmospheric methane consumption rates during experimental manipulations of soil water content and water potential. maximum rates of atmospheric methane consumption occurred at a soil water content of 25% (grams per gram [dry weight]) and a water potential of about -0.2 mpa. in contrast, uptake rates were highest at a water content of 38% and a water potential of -0.03 mpa when methane was ...	1996	16535395
transformation kinetics of chlorinated ethenes by methylosinus trichosporium ob3b and detection of unstable epoxides by on-line gas chromatography.	a rapid and accurate method for the determination of transformation kinetics of volatile organic substrates was developed. concentrations were monitored by on-line gas chromatographic analysis of the headspace of well-mixed incubation mixtures. with this method, the kinetics of transformation of a number of c(inf1) and c(inf2) halogenated alkanes and alkenes by methylosinus trichosporium ob3b expressing particulate methane monooxygenase or soluble methane monooxygenase (smmo) were studied. appar ...	1996	16535402
biodegradation of individual and multiple chlorinated aliphatic hydrocarbons by methane-oxidizing cultures.	the microbial degradation of chlorinated and nonchlorinated methanes, ethanes, and ethanes by a mixed methane-oxidizing culture grown under chemostat and batch conditions is evaluated and compared with that by two pure methanotrophic strains: cac1 (isolated from the mixed culture) and methylosinus trichosporium ob3b. with the exception of 1,1-dichloroethylene, the transformation capacity (tc) for each chlorinated aliphatic hydrocarbon was generally found to be in inverse proportion to its chlori ...	1996	8795228
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
the soluble methane monooxygenase gene cluster of the trichloroethylene-degrading methanotroph methylocystis sp. strain m.	in methanotrophic bacteria, methane is oxidized to methanol by the enzyme methane monooxygenase (mmo). the soluble mmo enzyme complex from methylocystis sp. strain m also oxidizes a wide range of aliphatic and aromatic compounds, including trichloroethylene. in this study, heterologous dna probes from the type ii methanotroph methylosinus trichosporium ob3b were used to isolate souble mmo (smmo) genes from the type ii methanotroph methylocystis sp. strain m. smmo genes from strain m are clustere ...	1997	9143121
chloroform cometabolism by butane-grown cf8, pseudomonas butanovora, and mycobacterium vaccae job5 and methane-grown methylosinus trichosporium ob3b.	chloroform (cf) degradation by a butane-grown enrichment culture, cf8, was compared to that by butane-grown pseudomonas butanovora and mycobacterium vaccae job5 and to that by a known cf degrader, methylosinus trichosporium ob3b. all three butane-grown bacteria were able to degrade cf at rates comparable to that of m. trichosporium. cf degradation by all four bacteria required o(inf2). butane inhibited cf degradation by the butane-grown bacteria, suggesting that butane monooxygenase is responsib ...	1997	16535693
effect of chlorinated ethene conversion on viability and activity of methylosinus trichosporium ob3b.	the effect of transformation of chlorinated ethenes on the cell viability of methylosinus trichosporium ob3b was investigated. a comparison of the loss of viability with the decrease in transformation rates showed that for the monooxygenase-mediated transformation of all chlorinated ethenes except vinyl chloride the decrease in cell viability was the predominant toxic effect.	1997	16535757
effect of trichloroethylene on the competitive behavior of toluene-degrading bacteria.	the influence of trichloroethylene (tce) on a mixed culture of four different toluene-degrading bacterial strains (pseudomonas putida mt-2, p. putida f1, p. putida gj31, and burkholderia cepacia g4) was studied with a fed-batch culture. the strains were competing for toluene, which was added at a very low rate (31 nmol mg of cells [dry weight] h). all four strains were maintained in the mixed culture at comparable numbers when tce was absent. after the start of the addition of tce, the viabiliti ...	1998	16349481
effects of ammonium and non-ammonium salt additions on methane oxidation by methylosinus trichosporium ob3b and maine forest soils.	additions of ammonium and non-ammonium salts inhibit atmospheric methane consumption by soil at salt concentrations that do not significantly affect the soil water potential. the response of soils to non-ammonium salts has previously raised questions about the mechanism of ammonium inhibition. results presented here show that inhibition of methane consumption by non-ammonium salts can be explained in part by ion-exchange reactions: cations desorb ammonium, with the level of desorption varying as ...	1998	16349485
methanol promotes atmospheric methane oxidation by methanotrophic cultures and soils.	two methanotrophic bacteria, methylobacter albus bg8 and methylosinus trichosporium ob3b, oxidized atmospheric methane during batch growth on methanol. methane consumption was rapidly and substantially diminished (95% over 9 days) when washed cell suspensions were incubated without methanol in the presence of atmospheric methane (1.7 ppm). methanotrophic activity was stimulated after methanol (10 mm) but not methane (1,000 ppm) addition. m. albus bg8 grown in continuous culture for 80 days with ...	1998	16349514
characterization of root-associated methanotrophs from three freshwater macrophytes: pontederia cordata, sparganium eurycarpum, and sagittaria latifolia.	root-associated methanotrophic bacteria were enriched from three common aquatic macrophytes: pontederia cordata, sparganium eurycarpum, and sagittaria latifolia. at least seven distinct taxa belonging to groups i and ii were identified and presumptively assigned to the genera methylosinus, methylocystis, methylomonas, and methylococcus. four of these strains appeared to be novel on the basis of partial 16s ribosomal dna sequence analysis. the root-methanotroph association did not appear to be hi ...	1998	16349515
methane and trichloroethylene degradation by methylosinus trichosporium ob3b expressing particulate methane monooxygenase.	whole-cell assays of methane and trichloroethylene (tce) consumption have been performed on methylosinus trichosporium ob3b expressing particulate methane monooxygenase (pmmo). from these assays it is apparent that varying the growth concentration of copper causes a change in the kinetics of methane and tce degradation. for m. trichosporium ob3b, increasing the copper growth concentration from 2.5 to 20 mum caused the maximal degradation rate of methane (v(max)) to decrease from 300 to 82 nmol o ...	1998	16349516
effect of selected monoterpenes on methane oxidation, denitrification, and aerobic metabolism by bacteria in pure culture.	selected monoterpenes inhibited methane oxidation by methanotrophs (methylosinus trichosporium ob3b, methylobacter luteus), denitrification by environmental isolates, and aerobic metabolism by several heterotrophic pure cultures. inhibition occurred to various extents and was transient. complete inhibition of methane oxidation by methylosinus trichosporium ob3b with 1.1 mm (-)-alpha-pinene lasted for more than 2 days with a culture of optical density of 0.05 before activity resumed. inhibition w ...	1998	9464387
acidophilic methanotrophic communities from sphagnum peat bogs.	highly enriched methanotrophic communities (> 25 serial transfers) were obtained from acidic ombrotrophic peat bogs from four boreal forest sites. the enrichment strategy involved using media conditions that were associated with the highest rates of methane uptake by the original peat samples, namely, the use of diluted mineral medium of low buffering capacity, moderate incubation temperature (20 degrees c), and ph values of 3 to 6. enriched communities contained a mixture of rod-shaped bacteria ...	1998	9501432
isolation of copper biochelates from methylosinus trichosporium ob3b and soluble methane monooxygenase mutants.	methylosinus trichosporium ob3b produces an extracellular copper-binding ligand (cbl) with high affinity for copper. wild-type cells and mutants that express soluble methane monooxygenase (smmo) in the presence and absence of copper (smmoc) were used to obtain cell exudates that were separated and analyzed by size exclusion high-performance liquid chromatography. a single chromatographic peak, when present, contained most of the aqueous-phase cu(ii) present in the culture medium. in mutant cultu ...	1998	9501450
effects of bacterial host and dichloromethane dehalogenase on the competitiveness of methylotrophic bacteria growing with dichloromethane.	methylobacterium sp. strain dm4 and methylophilus sp. strain dm11 can grow with dichloromethane (dcm) as the sole source of carbon and energy by virtue of homologous glutathione-dependent dcm dehalogenases with markedly different kinetic properties (the kcat values of the enzymes of these strains are 0.6 and 3.3 s-1, respectively, and the km values are 9 and 59 microm, respectively). these strains, as well as transconjugant bacteria expressing the dcm dehalogenase gene (dcma) from dm11 or dm4 on ...	1998	9546153
a novel phosphorylation-dependent rnase activity of gap-sh3 binding protein: a potential link between signal transduction and rna stability.	a potential p120 gtpase-activating protein (rasgap) effector, g3bp (rasgap src homology 3 [sh3] binding protein), was previously identified based on its ability to bind the sh3 domain of rasgap. here we show that g3bp colocalizes and physically interacts with rasgap at the plasma membrane of serum-stimulated but not quiescent chinese hamster lung fibroblasts. in quiescent cells, g3bp was hyperphosphorylated on serine residues, and this modification was essential for its activity. indeed, g3bp ha ...	1998	9632780
construction and use of an ipb dna module to generate pseudomonas strains with constitutive trichloroethene and isopropylbenzene oxidation activity.	pseudomonas sp. strain jr1 exhibits trichloroethene (tce) oxidation activity with isopropylbenzene (ipb) as the inducer substrate. we previously reported the genes encoding the first three enzymes of the ipb-degradative pathway (ipba1, ipba2, ipba3, ipba4, ipbb, and ipbc) and identified the initial ipb dioxygenase (ipba1 a2a3a4) as responsible for tce cooxidation (u. pflugmacher, b. averhoff, and g. gottschalk, appl. environ. microbiol. 62:3967-3977, 1996). primer extension analyses revealed mul ...	1998	9647815
copper-binding compounds from methylosinus trichosporium ob3b.	two copper-binding compounds/cofactors (cbcs) were isolated from the spent media of both the wild type and a constitutive soluble methane monooxygenase (smmoc) mutant, pp319 (p. a. phelps et al., appl. environ. microbiol. 58:3701-3708, 1992), of methylosinus trichosporium ob3b. both cbcs are small polypeptides with molecular masses of 1,218 and 779 da for cbc-l1 and cbc-l2, respectively. the amino acid sequence of cbc-l1 is s?mypgs?m, and that of cbc-l2 is spmp?s. copper-free cbcs showed absorpt ...	1998	9658004
a glutathione s-transferase with activity towards cis-1, 2-dichloroepoxyethane is involved in isoprene utilization by rhodococcus sp. strain ad45.	rhodococcus sp. strain ad45 was isolated from an enrichment culture on isoprene (2-methyl-1,3-butadiene). isoprene-grown cells of strain ad45 oxidized isoprene to 3,4-epoxy-3-methyl-1-butene, cis-1, 2-dichloroethene to cis-1,2-dichloroepoxyethane, and trans-1, 2-dichloroethene to trans-1,2-dichloroepoxyethane. isoprene-grown cells also degraded cis-1,2-dichloroepoxyethane and trans-1, 2-dichloroepoxyethane. all organic chlorine was liberated as chloride during degradation of cis-1,2-dichloroepox ...	1998	9687433
oxidation of trichloroethylene, 1,1-dichloroethylene, and chloroform by toluene/o-xylene monooxygenase from pseudomonas stutzeri ox1.	toluene/o-xylene monooxygenase (tomo) from pseudomonas stutzeri ox1, which oxidizes toluene and o-xylene, was examined for its ability to degrade the environmental pollutants trichloroethylene (tce), 1, 1-dichloroethylene (1,1-dce), cis-1,2-dce, trans-1,2-dce, chloroform, dichloromethane, phenol, 2,4-dichlorophenol, 2,4,5-trichlorophenol, 2,4,6-trichlorophenol, 2,3,5,6-tetrachlorophenol, and 2,3,4,5, 6-pentachlorophenol. escherichia coli jm109 that expressed tomo from genes on plasmid pbz1260 un ...	1998	9687467
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
analysis of the gene cluster encoding toluene/o-xylene monooxygenase from pseudomonas stutzeri ox1.	the toluene/o-xylene monooxygenase cloned from pseudomonas stutzeri ox1 displays a very broad range of substrates and a very peculiar regioselectivity, because it is able to hydroxylate more than one position on the aromatic ring of several hydrocarbons and phenols. the nucleotide sequence of the gene cluster coding for this enzymatic system has been determined. the sequence analysis revealed the presence of six open reading frames (orfs) homologous to other genes clustered in operons coding for ...	1998	9758777
distribution and life strategies of two bacterial populations in a eutrophic lake	monoclonal antibodies and epifluorescence microscopy were used to determine the depth distribution of two indigenous bacterial populations in the stratified lake plusssee and characterize their life strategies. populations of comamonas acidovorans px54 showed a depth distribution with maximum abundances in the oxic epilimnion, whereas aeromonas hydrophila pu7718 showed a depth distribution with maximum abundances in the anoxic thermocline layer (metalimnion), i. e., in the water layer with the h ...	1998	9758799
identification of chlorobenzene dioxygenase sequence elements involved in dechlorination of 1,2,4,5-tetrachlorobenzene.	the teca chlorobenzene dioxygenase and the todcba toluene dioxygenase exhibit substantial sequence similarity yet have different substrate specificities. escherichia coli cells producing recombinant teca enzyme dioxygenate and simultaneously eliminate a halogen substituent from 1,2,4,5-tetrachlorobenzene but show no activity toward benzene, whereas those producing todcba dioxygenate benzene but not tetrachlorobenzene. a hybrid teca dioxygenase variant containing the large alpha-subunit of the to ...	1998	9791099
low-concentration kinetics of atmospheric ch4 oxidation in soil and mechanism of nh4+ inhibition	nh4+ inhibition kinetics for ch4 oxidation were examined at near-atmospheric ch4 concentrations in three upland forest soils. whether nh4+-independent salt effects could be neutralized by adding nonammoniacal salts to control samples in lieu of deionized water was also investigated. because the levels of exchangeable endogenous nh4+ were very low in the three soils, desorption of endogenous nh4+ was not a significant factor in this study. the km(app) values for water-treated controls were 9.8, 2 ...	1998	9797279
whole-cell kinetics of trichloroethylene degradation by phenol hydroxylase in a ralstonia eutropha jmp134 derivative	the rate, progress, and limits of trichloroethylene (tce) degradation by ralstonia eutropha aek301/pyk3021 whole cells were examined in the absence of aromatic induction. at tce concentrations up to 800 &mgr;m, degradation rates were sustained until tce was no longer detectable. the ks and vmax for tce degradation by aek301/pyk3021 whole cells were determined to be 630 &mgr;m and 22.6 nmol/min/mg of total protein, respectively. the sustained linear rates of tce degradation by aek301/pyk3021 up t ...	1998	9797289
molecular detection, isolation, and physiological characterization of functionally dominant phenol-degrading bacteria in activated sludge.	dna was isolated from phenol-digesting activated sludge, and partial fragments of the 16s ribosomal dna (rdna) and the gene encoding the largest subunit of multicomponent phenol hydroxylase (lmph) were amplified by pcr. an analysis of the amplified fragments by temperature gradient gel electrophoresis (tgge) demonstrated that two major 16s rdna bands (bands r2 and r3) and two major lmph gene bands (bands p2 and p3) appeared after the activated sludge became acclimated to phenol. the nucleotide s ...	1998	9797297
methanotrophs and methanogens in masonry	methanotrophs were present in 48 of 225 stone samples which were removed from 19 historical buildings in germany and italy. the average cell number of methanotrophs was 20 cfu per g of stone, and their activities ranged between 11 and 42 pmol of ch4 g of stone-1 day-1. twelve strains of methane-oxidizing bacteria were isolated. they belonged to the type ii methanotrophs of the genera methylocystis, methylosinus, and methylobacterium. in masonry, growth substrates like methane or methanol are ava ...	1998	9797318
assessment of changes in microbial community structure during operation of an ammonia biofilter with molecular tools.	biofiltration has been used for two decades to remove odors and various volatile organic and inorganic compounds in contaminated off-gas streams. although biofiltration is widely practiced, there have been few studies of the bacteria responsible for the removal of air contaminants in biofilters. in this study, molecular techniques were used to identify bacteria in a laboratory-scale ammonia biofilter. both 16s rrna and ammonia monooxygenase (amoa) genes were used to characterize the heterotrophi ...	1998	9835577
induction of the tod operon by trichloroethylene in pseudomonas putida tva8.	bioluminescence, mrna levels, and toluene degradation rates in pseudomonas putida tva8 were measured as a function of various concentrations of toluene and trichloroethylene (tce). tva8 showed an increasing bioluminescence response to increasing tce and toluene concentrations. compared to uninduced tva8 cultures, todc1 mrna levels increased 11-fold for tce-treated cultures and 13-fold for toluene-treated cultures. compared to uninduced p. putida f1 cultures, todc1 mrna levels increased 4.4-fold ...	1998	9835608
cytochrome p460 genes from the methanotroph methylococcus capsulatus bath.	p460 cytochromes catalyze the oxidation of hydroxylamine to nitrite. they have been isolated from the ammonia-oxidizing bacterium nitrosomonas europaea (r. h. erickson and a. b. hooper, biochim. biophys. acta 275:231-244, 1972) and the methane-oxidizing bacterium methylococcus capsulatus bath (j. a. zahn et al., j. bacteriol. 176:5879-5887, 1994). a degenerate oligonucleotide probe was synthesized based on the n-terminal amino acid sequence of cytochrome p460 and used to identify a dna fragment ...	1998	9851984
use of an oxygen-insensitive microscale biosensor for methane to measure methane concentration profiles in a rice paddy.	an oxygen-insensitive microscale biosensor for methane was constructed by furnishing a previously described biosensor with an oxygen guard. the guard consisted of a glass capillary containing heterotrophic bacteria, which consumed oxygen diffusing through the tip membrane, thus preventing it from diffusing into the methane-sensing unit. oxygen microprofiles were measured through the oxygen guard capillary, demonstrating the principle and limitations of the method. when the tip of the guard capil ...	1998	16349527
bacterial oxidation of dibromomethane and methyl bromide in natural waters and enrichment cultures	bacterial oxidation of 14ch2br2 and 14ch3br was measured in freshwater, estuarine, seawater, and hypersaline-alkaline samples. in general, bacteria from the various sites oxidized similar amounts of 14ch2br2 and comparatively less 14ch3br. bacterial oxidation of 14ch3br was rapid in freshwater samples compared to bacterial oxidation of 14ch3br in more saline waters. freshwater was also the only site in which methyl fluoride-sensitive bacteria (e.g., methanotrophs or nitrifiers) governed brominat ...	1998	9835541
spreadsheet method for evaluation of biochemical reaction rate coefficients and their uncertainties by weighted nonlinear least-squares analysis of the integrated monod equation	a convenient method for evaluation of biochemical reaction rate coefficients and their uncertainties is described. the motivation for developing this method was the complexity of existing statistical methods for analysis of biochemical rate equations, as well as the shortcomings of linear approaches, such as lineweaver-burk plots. the nonlinear least-squares method provides accurate estimates of the rate coefficients and their uncertainties from experimental data. linearized methods that involve ...	1998	9603812
atmospheric methane consumption by forest soils and extracted bacteria at different ph values.	the effect of ph on atmospheric methane (ch4) consumption was studied with slurries of forest soils and with bacteria extracted from the same soils. soil samples were collected from a mixed hardwood stand in new hampshire, from jackpine and aspen stands at the boreas (boreal ecosystem atmosphere study) site near thompson, northern manitoba, from sites in southern québec, including a beech stand and a meadow, and from a site in ontario (cultivated humisol). consumption of atmospheric ch4 (concent ...	1998	9647806
attributes of atmospheric carbon monoxide oxidation by maine forest soils.	co, one of the most important trace gases, regulates tropospheric methane, hydroxyl radical, and ozone contents. ten to 25% of the estimated global co flux may be consumed by soils annually. depth profiles for (14)co oxidation and co concentration indicated that co oxidation occurred primarily in surface soils and that photooxidation of soil organic matter did not necessarily contribute significantly to co fluxes. kinetic analyses revealed that the apparent k(m) was about 18 nm (17 ppm) and the ...	1999	10583974
inhibition of nitrifiers and methanotrophs from an agricultural humisol by allylsulfide and its implications for environmental studies.	allylsulfide, an inhibitor of ammonia monooxygenase, was tested to determine its ability to inhibit nitrification and methane oxidation in pure cultures, in agricultural humisol enrichment cultures, and in humisol slurries. we confirmed that allylsulfide is a differential inhibitor of cultures of nitrifiers and methanotrophs at concentrations of 1 and 200 microm, respectively, which result in 50% inhibition. however, although a nitrifying enrichment culture added to sterilized humisol was inhibi ...	1999	10347027
contribution of methanotrophic and nitrifying bacteria to ch4 and nh4+ oxidation in the rhizosphere of rice plants as determined by new methods of discrimination	methanotrophic and nitrifying bacteria are both able to oxidize ch4 as well as nh4+. to date it is not possible to estimate the relative contribution of methanotrophs to nitrification and that of nitrifiers to ch4 oxidation and thus to assess their roles in n and c cycling in soils and sediments. this study presents new options for discrimination between the activities of methanotrophs and nitrifiers, based on the competitive inhibitor ch3f and on recovery after inhibition with c2h2. by using ri ...	1999	10223965
detection of methanotrophs in groundwater by pcr.	methanotrophic bacteria have significant potential for bioremediation, which would require methods for monitoring the presence and activity of these organisms in environmental samples. in this study, pcr was used to detect methanotrophic bacteria. primers were designed on the basis of a partial sequence of pmoa, which encodes one of the proteins of the particulate methane monooxygenase. specific amplification of a portion of pmoa was obtained with template dna isolated from lab strains of methan ...	1999	9925595
distribution of sulfate-reducing and methanogenic bacteria in anaerobic aggregates determined by microsensor and molecular analyses.	using molecular techniques and microsensors for h(2)s and ch(4), we studied the population structure of and the activity distribution in anaerobic aggregates. the aggregates originated from three different types of reactors: a methanogenic reactor, a methanogenic-sulfidogenic reactor, and a sulfidogenic reactor. microsensor measurements in methanogenic-sulfidogenic aggregates revealed that the activity of sulfate-reducing bacteria (2 to 3 mmol of s(2-) m(-3) s(-1) or 2 x 10(-9) mmol s(-1) per ag ...	1999	10508098
evaluation of toxic effects of aeration and trichloroethylene oxidation on methanotrophic bacteria grown with different nitrogen sources.	in this study we evaluated specific and nonspecific toxic effects of aeration and trichloroethylene (tce) oxidation on methanotrophic bacteria grown with different nitrogen sources (nitrate, ammonia, and molecular nitrogen). the specific toxic effects, exerted directly on soluble methane monooxygenase (smmo), were evaluated by comparing changes in methane uptake rates and naphthalene oxidation rates following aeration and/or tce oxidation. nonspecific toxic effects, defined as general cellular d ...	1999	9925614
radioactive fingerprinting of microorganisms that oxidize atmospheric methane in different soils.	microorganisms that oxidize atmospheric methane in soils were characterized by radioactive labelling with (14)ch(4) followed by analysis of radiolabelled phospholipid ester-linked fatty acids ((14)c-plfas). the radioactive fingerprinting technique was used to compare active methanotrophs in soil samples from greenland, denmark, the united states, and brazil. the (14)c-plfa fingerprints indicated that closely related methanotrophic bacteria were responsible for the oxidation of atmospheric methan ...	1999	10473417
characterization of methanotrophic bacterial populations in soils showing atmospheric methane uptake.	the global methane cycle includes both terrestrial and atmospheric processes and may contribute to feedback regulation of the climate. most oxic soils are a net sink for methane, and these soils consume approximately 20 to 60 tg of methane per year. the soil sink for atmospheric methane is microbially mediated and sensitive to disturbance. a decrease in the capacity of this sink may have contributed to the approximately 1%. year(-1) increase in the atmospheric methane level in this century. the ...	1999	10427012
high-molecular-mass multi-c-heme cytochromes from methylococcus capsulatus bath.	the polypeptide and structural gene for a high-molecular-mass c-type cytochrome, cytochrome c553o, was isolated from the methanotroph methylococcus capsulatus bath. cytochrome c553o is a homodimer with a subunit molecular mass of 124,350 da and an isoelectric point of 6. 0. the heme c concentration was estimated to be 8.2 +/- 0.4 mol of heme c per subunit. the electron paramagnetic resonance spectrum showed the presence of multiple low spin, s = 1/2, hemes. a degenerate oligonucleotide probe syn ...	1999	9922265
monitoring methanotrophic bacteria in hybrid anaerobic-aerobic reactors with pcr and a catabolic gene probe.	we attempted to mimic in small upflow anaerobic sludge bed (uasb) bioreactors the metabolic association found in nature between methanogens and methanotrophs. uasb bioreactors were inoculated with pure cultures of methanotrophs, and the bioreactors were operated by using continuous low-level oxygenation in order to favor growth and/or survival of methanotrophs. unlike the reactors in other similar studies, the hybrid anaerobic-aerobic bioreactors which we used were operated synchronously, not se ...	1999	9925557
influence of light intensity on methanotrophic bacterial activity in petit saut reservoir, french guiana.	one year after impoundment in january 1994, methanotrophic bacteria in petit saut reservoir (french guiana) were active at the oxic-anoxic interface. this activity was revealed by the sudden extinction of diffusive methane emission (600 metric tons of ch4. day-1 for the whole lake surface area, i.e., 360 km2). lifting of inhibition was suspected. after reviewing the potential inhibitors of this physiological guild (o2, nh4+, sulfides) and considering the similarities with nitrifiers, we suggest ...	1999	9925579
inactivation of toluene 2-monooxygenase in burkholderia cepacia g4 by alkynes.	high concentrations of acetylene (10 to 50% [vol/vol] gas phase) were required to inhibit the growth of burkholderia cepacia g4 on toluene, while 1% (vol/vol) (gas phase) propyne or 1-butyne completely inhibited growth. low concentrations of longer-chain alkynes (c5 to c10) were also effective inhibitors of toluene-dependent growth, and 2- and 3-alkynes were more potent inhibitors than their 1-alkyne counterparts. exposure of toluene-grown b. cepacia g4 to alkynes resulted in the irreversible lo ...	1999	9925593
high-affinity methane oxidation by a soil enrichment culture containing a type ii methanotroph.	methanotrophic bacteria in an organic soil were enriched on gaseous mixing ratios of <275 parts per million of volume (ppmv) of methane (ch4). after 4 years of growth and periodic dilution (>10(20) times the initial soil inoculum), a mixed culture was obtained which displayed an apparent half-saturation constant [km(app)] for ch4 of 56 to 186 nm (40 to 132 ppmv). this value was the same as that measured in the soil itself and about 1 order of magnitude lower than reported values for pure culture ...	1999	10049856
purification of a glutathione s-transferase and a glutathione conjugate-specific dehydrogenase involved in isoprene metabolism in rhodococcus sp. strain ad45.	a glutathione s-transferase (gst) with activity toward 1, 2-epoxy-2-methyl-3-butene (isoprene monoxide) and cis-1, 2-dichloroepoxyethane was purified from the isoprene-utilizing bacterium rhodococcus sp. strain ad45. the homodimeric enzyme (two subunits of 27 kda each) catalyzed the glutathione (gsh)-dependent ring opening of various epoxides. at 5 mm gsh, the enzyme followed michaelis-menten kinetics for isoprene monoxide and cis-1, 2-dichloroepoxyethane, with vmax values of 66 and 2.4 micromol ...	1999	10094686
molecular analysis of a novel methanesulfonic acid monooxygenase from the methylotroph methylosulfonomonas methylovora.	methylosulfonomonas methylovora m2 is an unusual gram-negative methylotrophic bacterium that can grow on methanesulfonic acid (msa) as the sole source of carbon and energy. oxidation of msa by this bacterium is carried out by a multicomponent msa monooxygenase (msamo). cloning and sequencing of a 7.5-kbp sphi fragment of chromosomal dna revealed four tightly linked genes encoding this novel monooxygenase. analysis of the deduced msamo polypeptide sequences indicated that the enzyme contains a tw ...	1999	10094704
the alkene monooxygenase from xanthobacter strain py2 is closely related to aromatic monooxygenases and catalyzes aromatic monohydroxylation of benzene, toluene, and phenol.	the genes encoding the six polypeptide components of the alkene monooxygenase from xanthobacter strain py2 (xamo) have been located on a 4.9-kb fragment of chromosomal dna previously cloned in cosmid pny2. sequencing and analysis of the predicted amino acid sequences indicate that the components of xamo are homologous to those of the aromatic monooxygenases, toluene 2-, 3-, and 4-monooxygenase and benzene monooxygenase, and that the gene order is identical. the genes and predicted polypeptides a ...	1999	10103255
molecular analyses of the methane-oxidizing microbial community in rice field soil by targeting the genes of the 16s rrna, particulate methane monooxygenase, and methanol dehydrogenase	rice field soil with a nonsaturated water content induced ch4 consumption activity when it was supplemented with 5% ch4. after a lag phase of 3 days, ch4 was consumed rapidly until the concentration was less than 1.8 parts per million by volume (ppmv). however, the soil was not able to maintain the oxidation activity at near-atmospheric ch4 mixing ratios (i.e., 5 ppmv). the soil microbial community was monitored by performing denaturing gradient gel electrophoresis (dgge) during the oxidation pr ...	1999	10223989
structure of the soluble methane monooxygenase regulatory protein b.	the soluble methane monooxygenase (smmo; ec 1.14.13.25) from the pseudothermophile methylococcus capsulatus (bath) is a three-component enzyme system that catalyzes the selective oxidation of methane to methanol. we have used nmr spectroscopy to produce a highly refined structure of mmob, the 16-kda regulatory protein of this system. this structure has a unique and intricate fold containing seven beta-strands forming two beta-sheets oriented perpendicular to each other and bridged by three alpha ...	1999	10393915
purification and characterization of the soluble methane monooxygenase of the type ii methanotrophic bacterium methylocystis sp. strain wi 14.	methane monooxygenase (mmo) catalyzes the oxidation of methane to methanol as the first step of methane degradation. a soluble nad(p)h-dependent methane monooxygenase (smmo) from the type ii methanotrophic bacterium wi 14 was purified to homogeneity. sequencing of the 16s rdna and comparison with that of other known methanotrophic bacteria confirmed that strain wi 14 is very close to the genus methylocystis. the smmo is expressed only during growth under copper limitation (<0.1 microm) and with ...	1999	10473397
distribution of tetrahydromethanopterin-dependent enzymes in methylotrophic bacteria and phylogeny of methenyl tetrahydromethanopterin cyclohydrolases.	the methylotrophic proteobacterium methylobacterium extorquens am1 possesses tetrahydromethanopterin (h(4)mpt)-dependent enzymes, which are otherwise specific to methanogenic and sulfate-reducing archaea and which have been suggested to be involved in formaldehyde oxidation to co(2) in m. extorquens am1. the distribution of h(4)mpt-dependent enzyme activities in cell extracts of methylotrophic bacteria from 13 different genera are reported. h(4)mpt-dependent activities were detected in all of th ...	1999	10482517
utilization of trihalogenated propanes by agrobacterium radiobacter ad1 through heterologous expression of the haloalkane dehalogenase from rhodococcus sp. strain m15-3.	trihalogenated propanes are toxic and recalcitrant organic compounds. attempts to obtain pure bacterial cultures able to use these compounds as sole carbon and energy sources were unsuccessful. both the haloalkane dehalogenase from xanthobacter autotrophicus gj10 (dhla) and that from rhodococcus sp. strain m15-3 (dhaa) were found to dehalogenate trihalopropanes to 2,3-dihalogenated propanols, but the kinetic properties of the latter enzyme are much better. broad-host-range dehalogenase expressio ...	1999	10508091
diversity in butane monooxygenases among butane-grown bacteria.	butane monooxygenases of butane-grown pseudomonas butanovora, mycobacterium vaccae job5, and an environmental isolate, cf8, were compared at the physiological level. the presence of butane monooxygenases in these bacteria was indicated by the following results. (i) o(2) was required for butane degradation. (ii) 1-butanol was produced during butane degradation. (iii) acetylene inhibited both butane oxidation and 1-butanol production. the responses to the known monooxygenase inactivator, ethylene, ...	1999	10508093
aerobic degradation of 1,1,1-trichloroethane by mycobacterium spp. isolated from soil.	two strains of 1,1,1-trichloroethane (tca)-degrading bacteria, ta5 and ta27, were isolated from soil and identified as mycobacterium spp. strains ta5 and ta27 could degrade 25 and 75 mg. liter of tca(-1) cometabolically in the presence of ethane as a carbon source, respectively. the compound 2,2,2-trichloroethanol was produced as a metabolite of the degradation process.	1999	10508110
methanotroph diversity in landfill soil: isolation of novel type i and type ii methanotrophs whose presence was suggested by culture-independent 16s ribosomal dna analysis.	the diversity of the methanotrophic community in mildly acidic landfill cover soil was assessed by three methods: two culture-independent molecular approaches and a traditional culture-based approach. for the first of the molecular studies, two primer pairs specific for the 16s rrna gene of validly published type i (including the former type x) and type ii methanotrophs were identified and tested. these primers were used to amplify directly extracted soil dna, and the products were used to const ...	1999	10543800
molecular characterization of functional and phylogenetic genes from natural populations of methanotrophs in lake sediments.	the 16s rrna and pmoa genes from natural populations of methane-oxidizing bacteria (methanotrophs) were pcr amplified from total community dna extracted from lake washington sediments obtained from the area where peak methane oxidation occurred. clone libraries were constructed for each of the genes, and approximately 200 clones from each library were analyzed by using restriction fragment length polymorphism (rflp) and the tetrameric restriction enzymes mspi, haeiii, and hhai. the pcr products ...	1999	10543824
soluble methane monooxygenase gene clusters from trichloroethylene-degrading methylomonas sp. strains and detection of methanotrophs during in situ bioremediation.	the soluble mmo (smmo) gene clusters from group i methanotrophs were characterized. an 8.1-kb kpni fragment from methylomonas sp. strain kswiii and a 7.5-kb sali fragment from methylomonas sp. strain kspiii which contained the smmo gene clusters were cloned and sequenced. the sequences of these two fragments were almost identical. the smmo gene clusters in the fragment consisted of six open reading frames which were 52 to 79% similar to the corresponding genes of previously described smmo gene c ...	1999	10583965
molecular analysis of the pmo (particulate methane monooxygenase) operons from two type ii methanotrophs.	the particulate methane monooxygenase gene clusters, pmocab, from two representative type ii methanotrophs of the alpha-proteobacteria, methylosinus trichosporium ob3b and methylocystis sp. strain m, have been cloned and sequenced. primer extension experiments revealed that the pmo cluster is probably transcribed from a single transcriptional start site located 300 bp upstream of the start of the first gene, pmoc, for methylocystis sp. strain m. immediately upstream of the putative start site, c ...	2000	10698759
characterization of the gene cluster involved in isoprene metabolism in rhodococcus sp. strain ad45.	the genes involved in isoprene (2-methyl-1,3-butadiene) utilization in rhodococcus sp. strain ad45 were cloned and characterized. sequence analysis of an 8.5-kb dna fragment showed the presence of 10 genes of which 2 encoded enzymes which were previously found to be involved in isoprene degradation: a glutathione s-transferase with activity towards 1,2-epoxy-2-methyl-3-butene (isoi) and a 1-hydroxy-2-glutathionyl-2-methyl-3-butene dehydrogenase (isoh). furthermore, a gene encoding a second gluta ...	2000	10715003
effect of copper speciation on whole-cell soluble methane monooxygenase activity in methylosinus trichosporium ob3b.	soluble methane monooxygenase (smmo) activity in methylosinus trichosporium ob3b was found to be more strongly affected as copper-to-biomass ratios changed in a newly developed medium, m2m, which uses pyrophosphate for metal chelation, than in nitrate mineral salts (nms), which uses edta. when m2m medium was amended with edta, smmo activity was similar to that in nms medium, indicating that edta-bound copper had lower bioavailability than pyrophosphate-bound copper. edta did not limit the associ ...	2000	10742271