Publications

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effect of pumping on the spatio-temporal distribution of microbial communities in a water well field.a water well field adjacent to the north saskatchewan river (city of north battleford, saskatchewan, canada) with a history of rapid deterioration of both well water quality and yield was selected to study the spatial and temporal distribution of subsurface microbial communities and their response to water pumping. a range of conventional cultural, microscopic and molecular techniques, including confocal laser scanning microscopy (clsm), biolog, qpcr and denaturing gradient gel electrophoresis ( ...201222227241
activity and diversity of methanotrophic bacteria at methane seeps in eastern lake constance sediments.the activity and community structure of aerobic methanotrophic communities were investigated at methane seeps (pockmarks) in the littoral and profundal zones of an oligotrophic freshwater lake (lake constance, germany). measurements of potential methane oxidation rates showed that sediments inside littoral pockmarks are hot spots of methane oxidation. potential methane oxidation rates at littoral pockmark sites exceeded the rates of the surrounding sediment by 2 orders of magnitude. terminal res ...201121335392
identification of microbial communities involved in the methane cycle of a freshwater meromictic lake.lake pavin is a meromictic crater lake located in the french massif central area. in this ecosystem, most of methane produced in high quantity in the anoxic bottom layers, and especially in sediments, is consumed in the water column with only a small fraction of annual production reaching the atmosphere. this study assessed the diversity of methanogenic and methanotrophic populations along the water column and in sediments using pcr and rt-pcr-based approaches targeting functional genes, i.e. pm ...201121595728
methanotrophic community structure of aged refuse and its capability for methane bio-oxidation.aged refuse from waste landfills closed for eight years was examined and found to contain rich methanotrophs capable of biooxidation for methane. specially, community structure and methane oxidation capability of methanotrophs in the aged refuse were studied. the amount of methanotrophs ranged 61.97 x 10(3)-632.91 x 10(3) cells/g (in dry basis) in aged refuse from shanghai laogang landfill. type i and ii methanotrophs were found in the aged refuse in the presence of sterilized sewage sludge and ...201121790062
[analysis of phylogenetic criteria for estimation of the rank of taxa in methane-oxidizing bacteria].to determine a possibility of application of phylogenetic criteria for estimating the taxa rank, the intra- and interspecies, as well as intergeneric relatedness of methanotrophs on the basis of 16s rrna gene sequences was estimated. we used sequences of 16s rrna genes of the studied isolates of obligate methanotrophs which have been deposited in ucm (ukrainian collection of microorganisms), and of type strains of other obligate methanotrophs species (from genbank database). it is shown, that th ...201121598653
genome sequence of the arctic methanotroph methylobacter tundripaludum sv96.methylobacter tundripaludum sv96(t) (atcc baa-1195) is a psychrotolerant aerobic methane-oxidizing gammaproteobacterium (methylococcales, methylococcaceae) living in high arctic wetland soil. the strain was isolated from soil harvested in july 1996 close to the settlement ny-+àlesund, svalbard (78-¦56' n-11-¦53' e) and described as a novel species in 2006. the genome includes pmo and pxm operons encoding copper membrane monooxygenases (cu-mmos), genes required for nitrogen fixation and the nirs ...201121725021
community structure, abundance, and activity of methanotrophs in the zoige wetland of the tibetan plateau.the zoige wetland of the tibetan plateau is a high-altitude tundra wetland and one of the biggest methane emission centers in china. in this study, methanotrophs with respect to community structure, abundance, and activity were investigated in peat soils collected in the vicinity of different marshland plants that dominate different regions of the wetland, including polygonum amphibium, carex muliensis, and eleocharis valleculosa (ev). 16s rrna gene and particulate methane monooxygenase gene (pm ...201122159497
Diversity and phylogeny of the ectoine biosynthesis genes in aerobic, moderately halophilic methylotrophic bacteria.The genes of ectoine biosynthesis pathway were identified in six species of aerobic, slightly halophilic bacteria utilizing methane, methanol or methylamine. Two types of ectoine gene cluster organization were revealed in the methylotrophs. The gene cluster ectABC coding for diaminobutyric acid (DABA) acetyltransferase (EctA), DABA aminotransferase (EctB) and ectoine synthase (EctC) was found in methanotrophs Methylobacter marinus 7C and Methylomicrobium kenyense AMO1(T). In methanotroph Methylo ...201121971967
earthworm activity in a simulated landfill cover soil shifts the community composition of active methanotrophs.landfills represent a major source of methane in the atmosphere. in a previous study, we demonstrated that earthworm activity in landfill cover soil can increase soil methane oxidation capacity. in this study, a simulated landfill cover soil mesocosm (1 m × 0.15 m) was used to observe the influence of earthworms (eisenia veneta) on the active methanotroph community composition, by analyzing the expression of the pmoa gene, which is responsible for methane oxidation. mrna-based pmoa microarray an ...201121925596
Selection of Type I and Type II methanotrophic proteobacteria in a fluidized bed reactor under non-sterile conditions.Type II methanotrophs produce polyhydroxybutyrate (PHB), while Type I methanotrophs do not. A laboratory-scale fluidized bed reactor was initially inoculated with a Type II Methylocystis-like dominated culture. At elevated levels of dissolved oxygen (DO, 9 mg/L), pH of 6.2-6.5 with nitrate as the N-source, a Methylobacter-like Type I methanotroph became dominant within the biofilms which did not produce PHB. A shift to biofilms capable of PHB production was achieved by re-inoculating with Type I ...201121906939
methylovulum miyakonense gen. nov., sp. nov., a type i methanotroph isolated from forest soil.a novel methanotroph, designated strain ht12(t), was isolated from forest soil in japan. cells of strain ht12(t) were gram-reaction-negative, aerobic, non-motile, coccoid and formed pale-brown colonies. the strain grew only with methane and methanol as sole carbon and energy sources. cells grew at 5-34 °c (optimum 24-32 °c). the strain possessed both particulate and soluble methane monooxygenases and assimilated formaldehyde using the ribulose monophosphate pathway. the major cellular fatty acid ...201120435749
vertical profiles of abundance and potential activity of methane-oxidizing bacteria in sediment of lake biwa, japan.vertical profiles of the abundance, community composition, and potential activity of methane-oxidizing bacteria (mob) were investigated in the sediment of lake biwa. sediment samples were obtained from two sites at different water depths. the abundance of mob was assessed as the copy number of the pmoa gene (encoding the alpha subunit of particulate methane monooxygenase), measured with quantitative real-time pcr. abundance of the pmoa gene peaked in the 5-8 cm layer of the sediment from both si ...201122200642
stable isotope probing analysis of the diversity and activity of methanotrophic bacteria in soils from the canadian high arctic.the melting of permafrost and its potential impact on ch(4) emissions are major concerns in the context of global warming. methanotrophic bacteria have the capacity to mitigate ch(4) emissions from melting permafrost. here, we used quantitative pcr (qpcr), stable isotope probing (sip) of dna, denaturing gradient gel electrophoresis (dgge) fingerprinting, and sequencing of the 16s rrna and pmoa genes to study the activity and diversity of methanotrophic bacteria in active-layer soils from ellesme ...201020622133
strain-specific incorporation of methanotrophic biomass into eukaryotic grazers in a rice field soil revealed by plfa-sip.in wetland ecosystems, methane is actively utilized by methanotrophs. the immobilized methane carbon is then passed on to other organisms such as grazers. here, we traced the incorporation of methanotrophic biomass into eukaryotes in a rice field soil using phospholipid fatty acid stable-isotope probing (plfa-sip). addition of (13)c-labeled cells of five methanotrophs to soil (5 × 10(7) cells g(-1) soil) did not affect the co(2) release rate, but significantly increased the carbon isotopic ratio ...201021133958
diversity of methanotrophs in zoige wetland soils under both anaerobic and aerobic conditions.zoige wetland is one of the most important methane emission centers in china. the oxidation of methane in the wetland affects global warming, soil ecology and atmospheric chemistry. despite their global significance, microorganisms that consume methane in zoige wetland remain poorly characterized. in this study, we investigated methanotrophs diversity in soil samples from both anaerobic site and aerobic site in zoige wetland using pmoa gene as a molecular marker. the cloning library was construc ...201021179963
phylogenetic analysis of methanotrophic communities in cover soils of a landfill in ontario.we examined the methanotrophs in the trail road landfill soils, ottawa, ontario, through cultivation-independent molecular assay and the culturing approach. denaturing gradient gel electrophoresis (dgge) analysis of amplified methanotroph-specific 16s rdna gene fragments revealed a more diverse type i (rump pathway) methanotrophic community than type ii (serine pathway) in 17 soil samples taken along a 50 m transect. the type ii methanotrophic community was less diverse, with the dominance of me ...200919898553
diversity of aerobic methanotrophic bacteria in a permafrost active layer soil of the lena delta, siberia.with this study, we present first data on the diversity of aerobic methanotrophic bacteria (mob) in an arctic permafrost active layer soil of the lena delta, siberia. applying denaturing gradient gel electrophoresis and cloning of 16s ribosomal ribonucleic acid (rrna) and pmoa gene fragments of active layer samples, we found a general restriction of the methanotrophic diversity to sequences closely related to the genera methylobacter and methylosarcina, both type i mob. in contrast, we revealed ...200918592300
diversity and activity of methanotrophs in alkaline soil from a chinese coal mine.culture-independent molecular biological techniques, including 16s rrna gene and functional gene clone libraries and microarray analyses using pmoa (encoding a key subunit of particulate methane monooxygenase), were applied to investigate the methanotroph community structure in alkaline soil from a chinese coal mine. this environment contained a high diversity of methanotrophs, including the type ii methanotrophs methylosinus/methylocystis, type i methanotrophs related to methylobacter/methyloso ...200919515201
community structure of microorganisms associated with reddish-brown iron-rich snow.reddish-brown colored snow, containing spherical brown particles, has been observed in several mires in japan. in order to characterize this remarkable phenomenon, the microbial community and chemical species in snow were analyzed. a core sample of snow which had a colored region was investigated and it revealed vertical shifts in physicochemical characteristics and the microbial community structure. the abundance of particles peaked within the colored layer, and correlated with the amount of re ...200919560891
[specification of species status of some colleciton strains of methanotrophs].sequence-analysis of genes 16s rrna has demonstrated the high-level relationship (99%) of the strains methylobacter ucrainicus ucm b-3159, and methylobacter marinus a45(t). the strain ucm b-3159 has lower coefficients of similarity (97.4-96.4%) for other species of that genus. these strains are similar as to their phenotypical properties and form one branch on the dendrogram which demonstrates species relations of methylococcaceae family, that permitted reclassifying m. ucrainicus as m. marinus. ...200919663320
response of methanotrophic activity and community structure to temperature changes in a diffusive ch/o counter gradient in an unsaturated porous medium.microbial methane oxidation is a key process in the global methane cycle. in the context of global warming, it is important to understand the responses of the methane-oxidizing microbial community to temperature changes in terms of community structure and activity. we studied microbial methane oxidation in a laboratory-column system in which a diffusive ch(4)/o(2) counter gradient was maintained in an unsaturated porous medium at temperatures between 4 and 20 degrees c. methane oxidation was hig ...200919496819
an assessment of bacterial dysbiosis in pouchitis using terminal restriction fragment length polymorphisms of 16s ribosomal dna from pouch effluent microbiota.previous studies on dysbiosis and pouchitis using conventional culture techniques have been disappointing because of inherent limitations associated with the technique. this study was designed to use terminal restriction fragment length polymorphism to evaluate patients with and without pouchitis.200919617766
activity and diversity of methanotrophs in the soil-water interface and rhizospheric soil from a flooded temperate rice field.to combine molecular and cultivation techniques to characterize the methanotrophic community in the soil-water interface (swi) and rhizospheric soil from flooded rice fields in uruguay, a temperate region in south america.200919054233
diversity of the active methanotrophic community in acidic peatlands as assessed by mrna and sip-plfa analyses.the active methanotroph community was investigated for the first time in heather (calluna)-covered moorlands and sphagnum/eriophorum-covered uk peatlands. direct extraction of mrna from these soils facilitated detection of expression of methane monooxygenase genes, which revealed that particulate methane monooxygenase and not soluble methane monooxygenase was probably responsible for ch(4) oxidation in situ, because only pmoa transcripts (encoding a subunit of particulate methane monooxygenase) ...200818093158
classification of halo(alkali)philic and halo(alkali)tolerant methanotrophs provisionally assigned to the genera methylomicrobium and methylobacter and emended description of the genus methylomicrobium.the taxonomic positions of four aerobic, obligately halo(alkali)philic/-tolerant, methanotrophic bacteria previously affiliated with the genera methylobacter ('methylobacter alcaliphilus' strains 20z and 5z) and methylomicrobium (methylomicrobium strains amo1 and ni) were investigated. phylogenetic analysis of 16s rrna gene sequences indicated that the strains form a separate branch within the type i methanotrophic bacteria and are closely related to methylomicrobium pelagicum. dna-dna hybridiza ...200818319461
real-time detection of actively metabolizing microbes by redox sensing as applied to methylotroph populations in lake washington.redox sensor green (rsg), a novel fluorescent dye from invitrogen was employed as a tool for real-time detection of microbes metabolically active in situ, in combination with flow cytometry and cell sorting. lake washington sediment, an environment known for high rates of methane oxidation, was used as a model, and methylotrophs were targeted as a functional group. we first tested and optimized the performance of the dye with pure methylotroph cultures. most cells in actively growing cultures we ...200818607374
[effect of operational modes on community structure of type i methanotroph in the cover soil of municipal solid waste landfill].type i methanotroph is crucial for methane oxidization and it responses fast to the changes in environment. in this study, 16s rdna-based denaturing gradient gel electrophoresis (dgge) gene fingerprint technology was applied to investigate the effect of operational modes, i. e. high-density polyethylene liner (hdpe) isolation or subsurface irrigation of landfill leachate and vegetation, on community structure and diversity of type i methanotroph in soils covering municipal solid waste landfill. ...200819143406
methylosoma difficile gen. nov., sp. nov., a novel methanotroph enriched by gradient cultivation from littoral sediment of lake constance.a novel methanotroph, strain lc 2(t), was isolated from the littoral sediment of lake constance by enrichment in opposing gradients of methane and oxygen, followed by traditional isolation methods. strain lc 2(t) grows on methane or methanol as its sole carbon and energy source. it is a gram-negative, non-motile, pale-pink-coloured methanotroph showing typical intracytoplasmic membranes arranged in stacks. cells are coccoid, elliptical or rod-shaped and occur often in pairs. strain lc 2(t) grows ...200717473262
[detection of osmoprotector ectoine content in methylotrophic bacteria using of normal-phase high performance liquid chromatography].detection and quantitative analysis of ectoine in bacterial biomass were performed by normal-phase high performance liquid chromatography with ultraviolet detection at 230 nm. quantitative analysis was not hindered by glutamate and sucrose accumulation in bacteria. measurement of ectoine concentration in haloalkaliphilic methanotrophs methylobacter marinus 7c and methylomicrobium alcaliphilum 5s showed that ectoine accumulation reached maximum (5 and 12% of dry cell weight) in the presence of na ...200717476809
diversity and abundance of aerobic and anaerobic methane oxidizers at the haakon mosby mud volcano, barents sea.submarine mud volcanoes are formed by expulsions of mud, fluids, and gases from deeply buried subsurface sources. they are highly reduced benthic habitats and often associated with intensive methane seepage. in this study, the microbial diversity and community structure in methane-rich sediments of the haakon mosby mud volcano (hmmv) were investigated by comparative sequence analysis of 16s rrna genes and fluorescence in situ hybridization. in the active volcano center, which has a diameter of a ...200717369343
identity of active methanotrophs in landfill cover soil as revealed by dna-stable isotope probing.a considerable amount of methane produced during decomposition of landfill waste can be oxidized in landfill cover soil by methane-oxidizing bacteria (methanotrophs) thus reducing greenhouse gas emissions to the atmosphere. the identity of active methanotrophs in roscommon landfill cover soil, a slightly acidic peat soil, was assessed by dna-stable isotope probing (sip). landfill cover soil slurries were incubated with (13)c-labelled methane and under either nutrient-rich nitrate mineral salt me ...200717714486
effect of temperature on composition of the methanotrophic community in rice field and forest soil.temperature change affects methane consumption in soil. however, there is no information on possible temperature control of methanotrophic bacterial populations. therefore, we studied ch(4) consumption and populations of methanotrophs in an upland forest soil and a rice field soil incubated at different temperatures between 5 and 45 degrees c for up to 40 days. potential methane consumption was measured at 4% ch(4). the temporal progress of ch(4) consumption indicated growth of methanotrophs. bo ...200717725622
identification of active methanotrophs in a landfill cover soil through detection of expression of 16s rrna and functional genes.active methanotrophs in a landfill soil were revealed by detecting the 16s rrna of methanotrophs and the mrna transcripts of key genes involved in methane oxidation. new 16s rrna primers targeting type i and type ii methanotrophs were designed and optimized for analysis by denaturing gradient gel electrophoresis. direct extraction of rna from soil enabled the analysis of the expression of the functional genes: mmox, pmoa and mxaf, which encode subunits of soluble methane monooxygenase, particula ...200717922768
[phylogenetic characterization of endosymbionts of the hydrothermal vent mussel bathymodiolus azoricus by analysis of the 16s rrna, pmol, and cbba genes].in order to assess the phylogenetic diversity of the endosymbiotic microbial community of the gills of marine shellfish bathymodiolus azoricus, total dna was extracted from the gills. the pcr fragments corresponding to the genes encoding 16s rrna, ribulose-bisphosphate carboxylase (cbbl), and particulate methane monooxygenase (pmoa) were amplified, cloned, and sequenced. for the 16s rdna genes, only one phylotype was revealed; it belonged to the cluster of mytilidae thiotrophic symbionts within ...200617205805
the active methanotrophic community in hydromorphic soils changes in response to changing methane concentration.methanotrophic communities were studied in several periodically water-saturated gleyic soils. when sampled, each soil had an oxic upper layer and consumed methane from the atmosphere (at 1.75 ppmv). in most gleyic soils the k(m(app)) values for methane were between 70 and 800 ppmv. these are higher than most values observed in dry upland soils, but lower than those measured in wetlands. based on cultivation-independent retrieval of the pmoa-gene and quantification of partial pmoa gene sequences, ...200616423018
differential effects of nitrogenous fertilizers on methane-consuming microbes in rice field and forest soils.the impact of environmental perturbation (e.g., nitrogenous fertilizers) on the dynamics of methane fluxes from soils and wetland systems is poorly understood. results of fertilizer studies are often contradictory, even within similar ecosystems. in the present study the hypothesis of whether these contradictory results may be explained by the composition of the methane-consuming microbial community and hence whether methanotrophic diversity affects methane fluxes was investigated. to this end, ...200616461686
[reclassification of thermophylic methane-oxidizing bacteria with the use of sequence-analysis of 16s rrna genes].the authors have performed sequence-analysis of 16s rrna genes of thermophylic methane-oxidizing bacteria ucm b-3026, ucm b-3032, ucm b-3109, ucm b-3014 which were isolated from sludge pond of different regions in ukraine and deposited at ukrainian collection of microorganisms (ucm) as methylococcus thermophilus and "m. gracilis". a comparative analysis of 16s rrna gene sequences of the studied bacteria with those sequences of various strains of bacteria in the genbank databases has shown that t ...200616686213
cultivation of methanotrophic bacteria in opposing gradients of methane and oxygen.in sediments, methane-oxidizing bacteria live in opposing gradients of methane and oxygen. in such a gradient system, the fluxes of methane and oxygen are controlled by diffusion and consumption rates, and the rate-limiting substrate is maintained at a minimum concentration at the layer of consumption. opposing gradients of methane and oxygen were mimicked in a specific cultivation set-up in which growth of methanotrophic bacteria occurred as a sharp band at either c. 5 or 20 mm below the air-ex ...200616689866
methane- and sulfur-metabolizing microbial communities dominate the lost city hydrothermal field ecosystem.hydrothermal venting and the formation of carbonate chimneys in the lost city hydrothermal field (lchf) are driven predominantly by serpentinization reactions and cooling of mantle rocks, resulting in a highly reducing, high-ph environment with abundant dissolved hydrogen and methane. phylogenetic and terminal restriction fragment length polymorphism analyses of 16s rrna genes in fluids and carbonate material from this site indicate the presence of organisms similar to sulfur-oxidizing, sulfate- ...200616957253
methylobacter tundripaludum sp. nov., a methane-oxidizing bacterium from arctic wetland soil on the svalbard islands, norway (78 degrees n).a gram-negative, rod-shaped, non-motile, non-spore forming bacterium (sv96t) was isolated from wetland soil near ny-alesund, svalbard. on the basis of 16s rrna gene sequence similarity, strain sv96t was shown to belong to the gammaproteobacteria, related to methylobacter psychrophilus z-0021t (99.1 %), methylobacter luteus atcc 49878t (97.3 %), methylobacter marinus a45t (97.0 %) and methylobacter whittenburyi atcc 51738t (95.8 %); the closest related species within the genus methylomicrobium wi ...200616403874
diversity of oxygenase genes from methane- and ammonia-oxidizing bacteria in the eastern snake river plain aquifer.pcr amplification, restriction fragment length polymorphism, and phylogenetic analysis of oxygenase genes were used for the characterization of in situ methane- and ammonia-oxidizing bacteria from free-living and attached communities in the eastern snake river plain aquifer. the following three methane monooxygenase (mmo) pcr primer sets were used: a189-a682, which amplifies an internal region of both the pmoa gene of the mmo particulate form and the amoa gene of ammonia monooxygenase; a189-mb66 ...200515812034
diversity of methanotrophic bacteria in tropical upland soils under different land uses.three upland soils from thailand, a natural forest, a 16-year-old reforested site, and an agricultural field, were studied with regard to methane uptake and the community composition of methanotrophic bacteria (mb). the methane uptake rates were similar to rates described previously for forest and farmland soils of the temperate zone. the rates were lower at the agricultural site than at the native forest and reforested sites. the sites also differed in the mb community composition, which was ch ...200516000794
response and adaptation of different methanotrophic bacteria to low methane mixing ratios.described genera of methanotrophic bacteria are present in most upland soils, but it is not known whether these are sufficiently oligotrophic to oxidize methane at its trace atmospheric mixing ratio of 1.75 ppmv. members of the genera methylocystis, methylosinus, methylocaldum and methylobacter were isolated from different upland soils and compared with type strains for growth and activity under low methane mixing ratios. the specific affinity (a0s) varied by about one order of magnitude among d ...200516104854
bacterial populations active in metabolism of c1 compounds in the sediment of lake washington, a freshwater lake.active members of the bacterial community in the sediment of lake washington, with special emphasis on c1 utilizers, were identified by employing two complementary culture-independent approaches: reverse transcription of environmental mrna and 16s rrna combined with pcr (rt-pcr) and stable-isotope probing (sip) of dna with the 13c-labeled c1 substrates methanol, methylamine, formaldehyde, and formate. analysis of rt-pcr-amplified fragments of 16s rrna-encoding genes revealed that gammaproteobact ...200516269723
aerobic methanotrophic bacteria of cold ecosystems.this review summarizes the recent advances in understanding the ecophysiological role and structure-function features of methanotrophic bacteria living in various cold ecosystems. the occurrence of methanotrophs in a majority of psychrosphere sites was verified by direct measurement of their methane-utilizing activity, by electron microscopy and immunofluorescent observations, and analyses of specific signatures in cellular phospholipids and total dnas extracted from environmental samples. surpr ...200516329925
analysis of methane monooxygenase genes in mono lake suggests that increased methane oxidation activity may correlate with a change in methanotroph community structure.mono lake is an alkaline hypersaline lake that supports high methane oxidation rates. retrieved pmoa sequences showed a broad diversity of aerobic methane oxidizers including the type i methanotrophs methylobacter (the dominant genus), methylomicrobium, and methylothermus, and the type ii methanotroph methylocystis. stratification of mono lake resulted in variation of aerobic methane oxidation rates with depth. methanotroph diversity as determined by analysis of pmoa using new denaturing gradien ...200516204580
[physicochemical and biological factors affecting atmospheric methane oxidation in gray forest soils].the decline of methane oxidizing activities in gray forest soil upon its conversion into arable land was shown to be caused by major changes in biotic and physicochemical properties of soil. using the method of immune serums, methane-oxidizing bacteria were detected in both forest and agricultural soils, but their populations differed significantly in both abundance and composition. in the forest soil, the number of methanotrophs was an order of magnitude higher than in arable soil, amounting to ...200515938403
molecular diversity of methanotrophs in transbaikal soda lake sediments and identification of potentially active populations by stable isotope probing.soda lakes are an environment with an unusually high ph and often high salinity. to identify the active methanotrophs in the soda lake sediments, sediment slurries were incubated with a 10% (v/v) (13)ch(4) headspace and the (13)c-labelled dna was subsequently extracted from these sediments following cscl density gradient centrifugation. this dna was then used as a template for pcr amplification of 16s rrna genes and genes encoding pmoa and mmox of methane monooxygenase, key enzymes in the methan ...200415344930
utility of environmental primers targeting ancient enzymes: methylotroph detection in lake washington.methods have been explored for detection of methylotrophs in natural samples, using environmental primers based on genes involved in the tetrahydromethanopterin (h4mpt)-linked c1 transfer pathway. the underlying hypotheses were that the h4mpt-linked pathway is an ancient methylotrophy pathway, based on gene divergence, and that primers targeting more divergent genes will detect a broader variety of methylotrophs compared to the variety uncovered using probes and primers targeting highly conserve ...200415696380
diversity of kenyan soda lake alkaliphiles assessed by molecular methods.dna was extracted from water and sediment samples taken from soda lakes of the kenyan-tanzanian rift valley. dna was also extracted from microbial enrichment cultures of sediment samples. 16s rrna genes were amplified by the polymerase chain reaction and microbial diversity was studied using denaturing gradient gel electrophoresis (dgge) of 16s rdna amplicons. cloning and sequencing of single dgge bands showed that they usually contained mixed amplicons. several of the amplicon sequences had hig ...200415064991
new dgge strategies for the analyses of methanotrophic microbial communities using different combinations of existing 16s rrna-based primers.methane-oxidising microbial communities are studied intensively because of their importance for global methane cycling. a suite of molecular microbial techniques has been applied to the study of these communities. denaturing gradient gel electrophoresis (dgge) is a diversity screening tool combining high sample throughput with phylogenetic information of high resolution. the existing 16s rrna-based dgge assays available for methane-oxidising bacteria suffer from low-specificity, low phylogentic ...200416329903
diversity of methanotroph communities in a basalt aquifer.methanotrophic bacteria play an important role in global cycling of carbon and co-metabolism of contaminants. methanotrophs from pristine regions of the snake river plain aquifer (srpa; idaho, usa) were studied in order to gain insight into the native groundwater communities' genetic potential to carry out tce co-metabolism. wells were selected that were proximal to a tce plume believed to be undergoing natural attenuation. methane concentrations ranged from 1 to >1000 nm. carbon isotope ratios ...200419712303
quantitative detection of methanotrophs in soil by novel pmoa-targeted real-time pcr assays.methane oxidation in soils is mostly accomplished by methanotrophic bacteria. little is known about the abundance of methanotrophs in soils, since quantification by cultivation and microscopic techniques is cumbersome. comparison of 16s ribosomal dna and pmoa (alpha subunit of the particulate methane monooxygenase) phylogenetic trees showed good correlation and revealed five distinct groups of methanotrophs within the alpha and gamma subclasses of proteobacteria: the methylococcus group, the met ...200312732507
wide distribution of a novel pmoa-like gene copy among type ii methanotrophs, and its expression in methylocystis strain sc2.experiments were conducted to determine if a novel pmoa-like gene (pmoa2) recently discovered in the methane-oxidizing bacterium methylocystis strain sc2 (p. f. dunfield, m. tchawa yimga, s. d. dedysh, u. berger, w. liesack, and j. heyer, fems microbiol. ecol. 41:17-26, 2002) is present in other methane-oxidizing bacteria (mob), and if it is expressed. a newly developed primer combination (pmoa206f-pmoa703b) allowed a differential detection of pmoa1 and pmoa2. by using this primer combination, w ...200312957949
characterization of methanogenic and methanotrophic assemblages in landfill samples.a greater understanding of the tightly linked trophic groups of anaerobic and aerobic bacteria residing in municipal solid waste landfills will increase our ability to control methane emissions and pollutant fate in these environments. to this end, we characterized the composition of methanogenic and methanotrophic bacteria in samples taken from two regions of a municipal solid waste landfill that varied in age. a method combining polymerase chain reaction amplification, restriction fragment len ...200314667383
methanotrophic diversity in high arctic wetlands on the islands of svalbard (norway)--denaturing gradient gel electrophoresis analysis of soil dna and enrichment cultures.the methanotrophic community in arctic soil from the islands of svalbard, norway (78 degrees n) was analysed by combining group-specific pcr with pcr of the highly variable v3 region of the 16s rrna gene and then by denaturing gradient gel electrophoresis (dgge). selected bands were sequenced for identification. the analyses were performed with dna extracted directly from soil and from enrichment cultures at 10 and 20 degrees c. the two genera methylobacter and methylosinus were found in all loc ...200314663494
[utilization of methane and carbon dioxide by symbiotrophic bacteria in gills of mytilidae (bathymodiolus) from the rainbow and logachev hydrothermal fields on the mid-atlantic ridge].bivalve mollusks bathymodiolus asoricus and bathymodiolus puteoserpentis collected from the rainbow and logachev hydrothermal fields during dives of mir 1 and mir 2 deep-sea manned submersibles were studied. rates of methane oxidation and carbon dioxide assimilation in mussel gill tissue were determined by radiolabel analysis. during oxidation of 14ch4, radiocarbon was detected in significant quantities not only in carbon dioxide but also in dissolved organic matter, most notably 14c-formate and ...200212449636
diversity of the particulate methane monooxygenase gene in methanotrophic samples from different rice field soils in china and the philippines.methanotrophic bacteria play a crucial role in regulating the emission of ch4 from rice fields into the atmosphere. we investigated the ch4 oxidation activity together with the diversity of methanotrophic bacteria in ten rice field soils from different geographic locations. upon incubation of aerated soil slurries under 7% ch4, rates of ch4 oxidation increased after a lag phase of 1-4 days and reached values of 3-10 micromol d(-1) g-dw(-1) soil. the methanotrophic community was assayed by retrie ...200212353882
[methanotrophs of the psychrophilic microbial community of the russian arctic tundra].in tundra, at a low temperature, there exists a slowly developing methanotrophic community. methane-oxidizing bacteria are associated with plants growing at high humidity, such as sedge and sphagnum; no methonotrophs were found in polytrichous and aulacomnious mosses and lichens, typical of more arid areas. the methanotrophic bacterial community inhabits definite soil horizons, from moss dust to peat formed from it. potential ability of the methanotrophic community to oxidize methane at 5 degree ...200212244726
[ethanol formation by methane-utilizing bacteria at ethane co-metabolism].it was established, that edta (1.0 mm) and formamide (100 mm) are inhibitors of methanol dehydrogenase in methylobacter luteus 12b, methylomonas rubra 15sh and methylococcus thermophilus 111p. the investigated strains co-metabolised ethane with the use of formate as the co-substrate. the application of formamide (or edta) as inhibitors of methanol dehydrogenase prevented from further transformation of ethanol and resulted in accumulation of extracellular ethanol. it was shown, that m. rubra 15sh ...200211944346
[methanotrophic communities in the soils of russian northern taiga and subarctic tundra].the pcr analysis of dna extracted from soil samples taken in russian northern taiga and subarctic tundra showed that the dna extracts contain genes specific to methanotrophic bacteria, i.e., the mmox gene encoding the conserved alpha-subunit of the hydroxylase component of soluble methane monooxygenase, the pmoa gene encoding the alpha-subunit of particulate methane monooxygenase, and the mxaf gene encoding the alpha-subunit of methanol dehydrogenase. pcr analysis with group-specific primers als ...200212024830
[study of nucleotide sequences of nifh genes in methanotrophic bacteria].using a previously developed primer system, nifh gene fragments 450 nucleotides long were amplified, cloned, and sequenced for representatives of nitrogen-fixing methanotrophic bacteria of the genera methylococcus, methylocystis and methylosinus. fragments of nifh genes were also detected and sequenced in representatives of the genera methylomonas and methylobacter, which were not considered diazotrophs until recently. phylogenetic analysis revealed remoteness of nifh genes sequences of methanot ...200212244720
methylosarcina fibrata gen. nov., sp. nov. and methylosarcina quisquiliarum sp.nov., novel type 1 methanotrophs.two novel species of obligate methane-oxidizing bacteria, isolated from landfill soil, were characterized. both strains were unusual in that some members of the population grew in irregularly shaped, refractile cell packets that resembled sarcina-like clusters. electron microscopy revealed that the cell packets were covered with a slime layer and the cells contained many large granular inclusion bodies. the individual cells of each strain were sometimes motile and had differing morphologies. iso ...200111321107
improved method for detection of methanotrophic bacteria in forest soils by pcr.a primer set was designed for the specific detection of methanotrophic bacteria in forest soils by pcr. the primer sequences were derived from highly conservative regions of the pmoa gene, encoding the alpha-subunit of the particulate methane monooxygenase present in all methanotrophs. in control experiments with genomic dna from a collection of different type i, ii, and x methanotrophs, it could be demonstrated that the new primers were specific for members of the genera methylosinus, methylocy ...200111400051
methanotrophic diversity in an agricultural soil as evaluated by denaturing gradient gel electrophoresis profiles of pmoa, mxaf and 16s rdna sequences.molecular methods were used to characterize the diversity of a methanotrophic population in an agricultural soil. for this purpose we have used dgge analysis of functional and phylogenetic markers. functional markers utilised comprised the pmoa-gene coding for the alpha-subunit of the particulate methane monooxygenase (pmmo) present in all known methanotrophs and the mxaf-gene coding for the alpha-subunit of methanol dehydrogenase (mdh) present in all gram-negative methylotrophs. in addition, we ...200111520007
detection of methanotroph diversity on roots of submerged rice plants by molecular retrieval of pmoa, mmox, mxaf, and 16s rrna and ribosomal dna, including pmoa-based terminal restriction fragment length polymorphism profiling.the diversity of methanotrophic bacteria associated with roots of submerged rice plants was assessed using cultivation-independent techniques. the research focused mainly on the retrieval of pmoa, which encodes the alpha subunit of the particulate methane monooxygenase. a novel methanotroph-specific community-profiling method was established using the terminal restriction fragment length polymorphism (t-rflp) technique. the t-rflp profiles clearly revealed a more complex root-associated methanot ...200111526021
[search for methanotrophic producers of exopolysaccharides].bacteria that produce exopolysaccharides (eps) and use methane as the only source of carbon were selected by studying a collection of methanotroph strains: methylococcus capsulatus e 494, 874, and 3009; m. thermophilus 111p, 112p, and 119p; methylobacter ucrainicus 159 and 161; m. luteus 57v and 12b; methylobacter sp. 100; methylomonas rubra 15 sh and sk-32; methylosinus trichosporium ov3b, ov5b and 4e; m. sporium 5, 12, a20d, and 90v; and methylocystis parvus ovvp. mesophilic methanotroph strai ...200111771325
family- and genus-level 16s rrna-targeted oligonucleotide probes for ecological studies of methanotrophic bacteria.methanotrophic bacteria play a major role in the global carbon cycle, degrade xenobiotic pollutants, and have the potential for a variety of biotechnological applications. to facilitate ecological studies of these important organisms, we developed a suite of oligonucleotide probes for quantitative analysis of methanotroph-specific 16s rrna from environmental samples. two probes target methanotrophs in the family methylocystaceae (type ii methanotrophs) as a group. no oligonucleotide signatures t ...200111571178
[growth of mesophilic methanotrophs at low temperatures].the optimal growth of mesophilic methanotrophic bacteria (collection strains of the genera methylocystis, methylomonas, methylosinus, and methylobacter) occurred within temperature ranges of 31-34 degrees c and 23-25 degrees c. none of the strains studied were able to grow at 1.5 or 4 degrees c. representatives of six methanotrophic species (strains mcs. echinoides 2, mm. methanica 12, mb. bovis 89, mcs. pyriformis 14, mb. chroococcum 90, and mb. vinelandii 87) could grow at 10 degrees c (with a ...200111558268
changes in activity and community structure of methane-oxidizing bacteria over the growth period of rice.the activity and community structure of methanotrophs in compartmented microcosms were investigated over the growth period of rice plants. in situ methane oxidation was important only during the vegetative growth phase of the plants and later became negligible. the in situ activity was not directly correlated with methanotrophic cell counts, which increased even after the decrease in in situ activity, possibly due to the presence of both vegetative cells and resting stages. by dividing the micro ...200111375143
bacterial populations occuring in a trichloroethylene-contaminated aquifer during methane injection.soil core samples were obtained from a trichloroethylene (tce)-contaminated aquifer before and after the start of methane biostimulation. dna was extracted directly from the soil samples, and denaturing gradient gel electrophoresis (dgge) was used to analyse bacterial 16s ribosomal dna fragments that were pcr amplified from these dna samples. this analysis consistently detected two phylotypes in the methane-injected samples. these phylotypes were closely related to methylobacter and methylomonas ...200111321535
differential inhibition in vivo of ammonia monooxygenase, soluble methane monooxygenase and membrane-associated methane monoxygenase by phenylacetylene.phenylacetylene was investigated as a differential inhibitor of ammonia monooxygenase (amo), soluble methane monooxygenase (smmo) and membrane-associated or particulate methane monooxygenase (pmmo) in vivo. at phenylacetylene concentrations > 1 microm, whole-cell amo activity in nitrosomonas europaea was completely inhibited. phenylacetylene concentrations above 100 microm inhibited more than 90% of smmo activity in methylococcus capsulatus bath and methylosinus trichosporium ob3b. in contrast, ...200011233157
[synthesis of osmoprotectors by halophilic and alkalophilic methanotrophs].the 1h-nmr analysis of methanol extracts of halophilic and halotolerant alkaliphilic methanotrophs isolated from the soda lakes of southern transbaikal and tuva showed that bacterial cells grown at an optimum salinity accumulated mainly sucrose and 5-oxo-1-proline, whereas cells adapted to 0.5-1.0 m nacl additionally synthesized ectoine. a more detailed study showed that nitrogen deficiency in the growth medium of methylobacter alcaliphilus 20z decreased the synthesis of nitrogen-containing osmo ...200011008680
an obligate methylotrophic, methane-oxidizing methylomicrobium species from a highly alkaline environment.a new, obligately methylotrophic, methane-oxidizing bacterium, strain amo 1, was isolated from a mixed sample of sediments from five highly alkaline soda lakes (kenya). based on its cell ultrastructure and high activity of the hexulose-6-phosphate synthase, the new isolate belongs to the type i methanotrophs. it differed, however, from the known neutrophilic methanotrophs by the ability to grow and oxidize methane at high ph values. the bacterium grew optimally with methane at ph 9-10. the oxida ...200010879559
fluorescent oligonucleotide rdna probes for specific detection of methane oxidising bacteria.oligonucleotide probes targeting the 16s rrna of distinct phylogenetic groups of methanotrophs were designed for the in situ detection of these organisms. a probe, mg-64, detected specifically type i methanotrophs, while probes ma-221 and ma-621, detected type ii methanotrophs in whole cell hybridisations. a probe mc1029 was also designed which targeted only organisms from the methylococcus genus after whole cell hybridisations. all probes were labelled with the fluorochrome cy3 and optimum cond ...200010620716
production and consumption of nitric oxide by three methanotrophic bacteria.we studied nitrogen oxide production and consumption by methanotrophs methylobacter luteus (group i), methylosinus trichosporium ob3b (group ii), and an isolate from a hardwood swamp soil, here identified by 16s ribosomal dna sequencing as methylobacter sp. strain t20 (group i). all could consume nitric oxide (nitrogen monoxide, no), and produce small amounts of nitrous oxide (n(2)o). only methylobacter strain t20 produced large amounts of no (>250 parts per million by volume [ppmv] in the heads ...200010966405
methylomonas scandinavica sp. nov., a new methanotrophic psychrotrophic bacterium isolated from deep igneous rock ground water of sweden.methane-utilizing bacteria were enriched from deep igneous rock environments and affiliated by amplification of functional and phylogenetic gene probes. type i methanotrophs belonging to the genera methylomonas and methylobacter dominated in enrichment cultures from depths below 400 m. a pure culture of an obligate methanotroph (strain sr5) was isolated and characterized. pink-pigmented motile rods of the new isolate contained intracytoplasmic membranes as stacks of vesicles, assimilated methane ...199910794145
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 dehydrogenaserice 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 ...199910223989
osmoadaptation in halophilic and alkaliphilic methanotrophsby using (1)h- and (13)c-nmr spectroscopy, an accumulation of sucrose and two cyclic amino acids [ectoine (1,4,5, 6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid) and 5-oxoproline (pyrrolidone carboxylic acid)] was detected in the halotolerant methanotrophs methylobacter alcaliphilus 20z and methylobacter modestohalophilus 10s. the organic solute pool was found to increase upon raising the nacl concentration. in m. alcaliphilus 20z, the intracellular level of the total solutes was shown to be ...199910550474
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 ...199910543800
detection and partial characterization of bacteriocin in the methanotrophic bacterium methylobacter bovis.the strain methylobacter bovis 98 was selected among methanotrophic bacteria as one of the most active producers of secretory bacteriocin-like compounds. in the above strain this compound was shown to be a protein with a molecular weight of about 70 kd, relatively thermostable, having a bactericidal effect on closely related organisms. its properties as a whole are consistent with the accepted definition of bacteriocins, which so far have not been found in this group of microorganisms. a methodi ...19989864443
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 ...19989851984
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 ...19989464387
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 ...199816349514
methane and trichloroethylene oxidation by an estuarine methanotroph, methylobacter sp. strain bb5.1.an estuarine methanotroph was isolated from sediment enrichments and designated methylobacter sp. strain bb5.1. in cells grown on medium with added copper, oxidation of methane and trichloroethylene occurred with similar ks values, but the vmax for trichloroethylene oxidation was only 0.1% of the methane oxidation vmax. cells grown on low-copper medium did not oxidize trichloroethylene and showed a variable rate of methane oxidation.19979361449
cycloclasticus pugetii gen. nov., sp. nov., an aromatic hydrocarbon-degrading bacterium from marine sediments.three heterotrophic bacterial strains were isolated from different locations in puget sound, washington, by using biphenyl as the principal carbon source. these strains grow by using a limited number of organic compounds, including the aromatic hydrocarbons naphthalene, phenanthrene, anthracene, and toluene, as sole carbon sources. these aerobic, gram-negative rods are motile by means of single polar flagella. their 16s rrna sequences indicate that they are all members of the gamma subdivision o ...19957857792
the phylogenetic position of the family methylococcaceae.the 16s ribosomal dna-based phylogenetic positions of various members of the methylococcaceae (group i methanotrophs) were investigated. the methylococcaceae as a whole formed a distinct branch in the gamma subdivision of the proteobacteria, and this branch had five distinct subbranches. on the basis of a number of phenotypic traits, phospholipid fatty acid patterns, and the results of a 16s ribosomal dna analysis, we determined that the species belonging to one subbranch, methylobacter albus, m ...19957857800
the mxaakl genes of methylobacter albus bg8.the facultative methanol utilizer methylobacterium extorquens am1 contains at least three genes (mxaa, k and l) that encode functions involved in providing calcium to the holoenzyme of methanol dehydrogenase, the enzyme that oxidizes methanol to formaldehyde in this strain. methane-utilizing bacteria (methanotrophs) also contain methanol dehydrogenase, and evidence suggests that similar methanol oxidation (mox) functions may be present in some of these strains. dna fragments from methylobacteriu ...19958535527
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 ...199516535004
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 ...19957768803
sequence of the gene for a nad(p)-dependent formaldehyde dehydrogenase (class iii alcohol dehydrogenase) from a marine methanotroph methylobacter marinus a45.a fragment of methylobacter marinus a45 dna has been cloned and sequenced, and an open reading frame has been identified that could code for a 46-kda polypeptide. comparison of the deduced amino acid sequence of the polypeptide against the protein data bank has revealed strong similarity with a number of alcohol dehydrogenases, with highest similarity towards class iii alcohol dehydrogenases, which recently have been shown to be identical to glutathione-dependent formaldehyde dehydrogenases. we ...19947926692
identification of a promoter region for mxaf (moxf) from the type i methanotroph, methylobacter albus bg8.a fragment of methylobacter albus bg8 dna containing mxaf (moxf), the gene encoding the alpha subunit of methanol dehydrogenase, was previously cloned using a fragment of mxaf from methylobacterium extorquens am1 as a probe (stephens et al., j. bacteriol. (1988) 170, 2063-2069). in this study we identified the 5' portion of mxaf of m. albus bg8 and sequenced a 1.7-kb region containing the 5' portion of mxaf and 1.5 kb of upstream dna. the deduced n-terminal amino acid sequence of mxaf was found ...19947926691
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 ...199416349402
a pseudo-outbreak of methylobacterium mesophilica isolated from patients undergoing bronchoscopy.an unusual, slow growing, pink-pigmented gram-negative bacillus was isolated from bronchoscopy specimens of seven patients over a three-month period. the organism was identified as methylobacter mesophilica. none of the patients were believed to be infected with methylobacter mesophilica. the results of environmental cultures showed that the organism was present in tap water from the bronchoscopy room.19921597201
[numerical analysis of the protein electrophoregrams of obligate methanotrophic bacteria].the protein spectra for 70 strains of obligate methanotrophic bacteria were studied using electrophoresis in polyacrylamide gel with sodium dodecyl sulphate. the protein spectra of methylomonas methanica 12 and methylosinus trichosporium 44 did not change in the course of the culture growth. basing on the data obtained, the similarity coefficients were calculated for these strains. the numerical analysis of the similarity coefficients was done, and a dendrogram presenting the phylogenetic relati ...19816799757
[ability of obligate methylotrophs to perform nitrogen fixation].the ability for nitrification was studied among mesophilic and thermophilic cultures of obligate methylotrophs methylobacter ucrainicus, methylomonas methanica, and methylococcus thermophilus. the strains were almost incapable of nitrification under autotrophic conditions. in the presence of methane, however, they oxidized nh+4 to no-2: over 150 mg/litre no-2 nitrogen was found in the cultural broth. therefore, obligate methylotrophs are capable of heterotrophic nitrification. the level of nitri ...1977404513
[isolation and properties of new strains of obligate methanotrophs].new strains of obligate methanotrophic bacteria which assimilate only methane or methanol as the source of carbon and energy have been isolated. according to their morphology, ultrastructure, cultural and physiologo-biochemical characteristics, the bacteria were classed as methylobacter vinelandii, methylobacter bovis, methylobacter chroococcum and mehylosinus sporium. a new species methylocystis echinoides sp. nov. is described; it differs from other methanotrophs in certain morphological and p ...1977600092
[submicroscopic structure of the membrane apparatus of methanotrophic bakteria].the fine structure of the membrane apparatus in obligate methanotrophic bacteria, methylomonas methanica, methylomonas rubrum 15 and methylobacter bovis 53b was studied. complex intracytoplasmic membrane systems of the i type were found in all cultures, but they differed by their structure and spatial organization depending on microorganisms. the cytoplasmic membrane was shown to be involved in the formation of complex membrane structures. a scheme of the spatial organization of the intracytopla ...1976826763
[thermophilic and thermotolerant bacteria that assimilate methane].microorganisms assimilating methane at temperatures above 40 degrees c were isolated from various natural sources: ooze, mud, waste water of coal pits. the bacteria are obligate methylotrophs and are represented by two groups: (a) thermotolerant, growing at 37 to 45 degrees c; and (b) thermophilic, growing at 50 to 62 degrees c. the selective factor used to isolate various physiological forms of methylotrophs is corresponding temperatures of growth which allow to isolate from the same substrate ...19751207503
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