| analysis of smmo-containing type i methanotrophs in lake washington sediment. | methane-oxidizing bacteria (methanotrophs) containing soluble methane monooxygenase (smmo) are of interest in natural environments due to the high co-metabolic activity of this enzyme with contaminants such as trichloroethylene. we have analysed smmo-containing methanotrophs in sediment from a freshwater lake. environmental clone banks for a gene encoding a diagnostic smmo subunit (mmox) were generated using dna extracted from lake washington sediment and subjected to rflp analysis. representati ... | 2002 | 12220408 |
| 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 |
| spectroscopic and electrochemical properties of two azurins (az-iso1 and az-iso2) from the obligate methylotroph methylomonas sp. strain j and the structure of novel az-iso2. | two azurin-type blue copper proteins, which are related to the electron-transfer processes involving methylamine/methanol oxidation, have been spectroscopically and electrochemically characterized. the obligate methylotroph methylomonas sp. strain j gives rise to two azurins (az-isol and az-iso2) with methylamine dehydrogenase (madh-mj). the intense blue bands characteristic of az-iso1 and az-iso2 are observed at 621 and 616 nm in the visible absorption spectra respectively, being revealed at 62 ... | 1999 | 10631606 |
| [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 ... | 2002 | 12449636 |
| [the biodegradation of trichloroethylene by a methanotrophic bacterium]. | a methylomonas (strain gyj3) isolated in our laboratory was identified as the type ii methanotroph on the basis of the intractytoplasmic membrane of the ultrastructure. the optimal culture conditions for production of the soluble from of methane monooxygenase (mmo) were determined, in which the ratio of methane to air in atmosphere was 2 to 1 and cu2+ concentration was 1.5 mumol/l. the biodegradation of trichoroethylene(tce) by the resting cells of the strain gyj3 was studied. all experiments we ... | 1998 | 12549391 |
| the ribulose-1,5-bisphosphate carboxylase/oxygenase gene cluster of methylococcus capsulatus (bath). | the genes encoding the ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) from methylococcus capsulatus (bath) were localised to an 8.3-kb ecori fragment of the genome. genes encoding the large subunit ( cbbl), small subunit ( cbbs) and putative regulatory gene ( cbbq) were shown to be located on one cluster. surprisingly, cbbo, a second putative regulatory gene, was not located in the remaining 1.2-kb downstream (3') of cbbq. however, probing of the m. capsulatus (bath) genome with cbbo ... | 2002 | 11889481 |
| 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 ... | 2001 | 11400051 |
| carbon isotopic fractionation in lipids from methanotrophic bacteria: relevance for interpretation of the geochemical record of biomarkers. | experiments with cultured aerobic methane oxidising bacteria confirm that their biomarker lipids will be significantly depleted in 13c compared to the substrate. the methanotrophic bacteria methylococcus capsulatus and methylomonas methanica, grown on methane and using the rump cycle for carbon assimilation, show maximum 13c fractionation of approximately 30% in the resultant biomass. in m. capsulatus, the maximum fractionation is observed in the earliest part of the exponential growth stage an ... | 1994 | 11540111 |
| the significance of the flexible loop in the azurin (az-iso2) from the obligate methylotroph methylomonas sp. strain j. | the obligate methylotroph methylomonas sp. strain j produces two azurins (az-iso1 and az-iso2) as candidates for electron acceptor from methylamine dehydrogenase (madh) in the electron-transfer process involving the oxidation of methylamine to formaldehyde and ammonia. the x-ray crystallographic study indicated that az-iso2 gives two types of crystals (form i and form ii) with polyethylene glycol (peg4000) and ammonium sulfate as the precipitants, respectively. comparison between the two az-iso2 ... | 2003 | 14516747 |
| formaldehyde fixation contributes to detoxification for growth of a nonmethylotroph, burkholderia cepacia tm1, on vanillic acid. | during bacterial degradation of methoxylated lignin monomers, such as vanillin and vanillic acid, formaldehyde is released through the reaction catalyzed by vanillic acid demethylase. when burkholderia cepacia tm1 was grown on vanillin or vanillic acid as the sole carbon source, the enzymes 3-hexulose-6-phosphate synthase (hps) and 6-phospho-3-hexuloisomerase (phi) were induced. these enzymes were also expressed during growth on luria-bertani medium containing formaldehyde. to understand the rol ... | 2003 | 14532071 |
| analysis of methanotrophic bacteria in movile cave by stable isotope probing. | movile cave is an unusual groundwater ecosystem that is supported by in situ chemoautotrophic production. the cave atmosphere contains 1-2% methane (ch4), although much higher concentrations are found in gas bubbles that keep microbial mats afloat on the water surface. as previous analyses of stable carbon isotope ratios have suggested that methane oxidation occurs in this environment, we hypothesized that aerobic methane-oxidizing bacteria (methanotrophs) are active in movile cave. to identify ... | 2004 | 14756876 |
| 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 ... | 2004 | 15344930 |
| [anaerobic methane oxidation]. | to clarify the biological mechanism of anaerobic methane oxidation, experiments were performed with samples of the black sea anaerobic sediments and with the aerobic methane-oxidizing bacterium methylomonas methanica strain 12. the inhibition-stimulation analysis did not allow an unambiguous conclusion to be made about direct and independent role of either methanogenic or sulfate-reducing microorganisms in the biogeochemical process of anaerobic methane oxidation. enrichment cultures obtained fr ... | 2004 | 15595522 |
| 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 ... | 2004 | 15696380 |
| amplification of marine methanotrophic enrichment dna with 16s rdna pcr primers for type ii alpha proteobacteria methanotrophs. | type ii alpha proteobacteria methanotrophs are capable of a wide range of cometabolic transformations of chlorinated solvents and polycyclic aromatic hydrocarbons (pahs), and this activity has been exploited in many terrestrial bioremediation systems. however, at present, all known obligately marine methanotrophic isolates are type i gamma proteobacteria which do not have this activity to the extent of type ii methanotrophs. in previous work in our laboratory, determining the presence of type ii ... | 2003 | 12940489 |
| stimulation of wheat morphogenesis in vitro by methanotrophic bacteria. | | 2003 | 12705138 |
| 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 ... | 2005 | 15812034 |
| novel carotenoid oxidase involved in biosynthesis of 4,4'-diapolycopene dialdehyde. | biosynthesis of c(30) carotenoids is relatively restricted in nature but has been described in staphylococcus and in methylotrophic bacteria. we report here identification of a novel gene (crtnb) involved in conversion of 4,4'-diapolycopene to 4,4'-diapolycopene aldehyde. an aldehyde dehydrogenase gene (ald) responsible for the subsequent oxidation of 4,4'-diapolycopene aldehyde to 4,4'-diapolycopene acid was also identified in methylomonas. crtnb has significant sequence homology with diapophyt ... | 2005 | 15933032 |
| [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 ... | 2005 | 15938403 |
| [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 ... | 2002 | 11944346 |
| 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 ... | 2003 | 12957949 |
| evolution of enzymatic activities in the orotidine 5'-monophosphate decarboxylase suprafamily: structural basis for catalytic promiscuity in wild-type and designed mutants of 3-keto-l-gulonate 6-phosphate decarboxylase. | 3-keto-l-gulonate 6-phosphate decarboxylase (kgpdc) and d-arabino-hex-3-ulose 6-phosphate synthase (hps), members of the orotidine 5'-monophosphate decarboxylase (ompdc) suprafamily, catalyze reactions that involve the formation of mg(2+)-ion stabilized 1,2-enediolate intermediates. the active sites of kgpdc and hps share several conserved residues, including the presumed ligands for the mg(2+) and a catalytic histidine residue that has been implicated in protonation of the intermediate in the k ... | 2005 | 15697207 |
| molecular detection and isolation from antarctica of methylotrophic bacteria able to grow with methylated sulfur compounds. | this study is the first demonstration that a diverse facultatively methylotrophic microbiota exists in some antarctic locations. pcr amplification of genes diagnostic for methylotrophs was carried out with bacterial dna isolated from 14 soil and sediment samples from ten locations on signy island, south orkney islands, antarctica. genes encoding the mxaf of methanol dehydrogenase, the fdxa for afipia ferredoxin, the msma of methanesulfonate monooxygenase, and the 16s rrna gene of methylobacteriu ... | 2005 | 16104352 |
| evolution of enzymatic activities in the orotidine 5'-monophosphate decarboxylase suprafamily: enhancing the promiscuous d-arabino-hex-3-ulose 6-phosphate synthase reaction catalyzed by 3-keto-l-gulonate 6-phosphate decarboxylase. | 3-keto-l-gulonate 6-phosphate decarboxylase (kgpdc) and d-arabino-hex-3-ulose 6-phosphate synthase (hps) are members of the orotidine 5'-monophosphate decarboxylase (ompdc) suprafamily [wise, e., yew, w. s., babbitt, p. c., gerlt, j. a., and rayment, i. (2002) biochemistry 41, 3861-3869], a group of homologous enzymes that share the (beta/alpha)(8)-barrel fold. kgpdc catalyzes a mg(2+)-dependent decarboxylation reaction in the catabolic pathway of l-ascorbate utilization by escherichia coli k-12 ... | 2005 | 15697206 |
| 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 ... | 2002 | 12353882 |
| 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 ... | 2005 | 16269723 |
| mutant of methylomonas methanolica and its characterization with respect to biomass production from methanol. | a stable variant of methylomonas methanolica, with a higher temperature optimum for growth, was obtained after mutagenic treatment and selection. the mutant strain m13v has an optimum growth temperature of 35 to 37 degrees c and a maximum at 43 degrees c, as compared with 30 and 40 degrees c for the wild strain. strain m13v and m. methanolica have similar basic characteristics and cell composition. an extracellular polysaccharide is produced by both strains, but this property is more pronounced ... | 1977 | 16345209 |
| distribution of methylomonas methanica and methylosinus trichosporium in cleveland harbor as determined by an indirect fluorescent antibody-membrane filter technique. | an indirect fluorescent antibody-membrane filter staining technique, which permitted the autecological study of methylomonas methanica and methylosinus trichosporium, was developed. this technique was used to assay the numbers of these two organisms in cleveland harbor. the concentrations of m. methanica and m. trichosporium were found to be inversely proportional to the sampling depth, with the highest cell counts observed in the sediments. m. methanica was observed at every sampling station, w ... | 1978 | 16345280 |
| [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 ... | 2002 | 12244720 |
| abundance, activity, and community structure of pelagic methane-oxidizing bacteria in temperate lakes. | the abundance and activity of methane-oxidizing bacteria (mob) in the water column were investigated in three lakes with different contents of nutrients and humic substances. the abundance of mob was determined by analysis of group-specific phospholipid fatty acids from type i and type ii mob, and in situ activity was measured with a 14ch4 transformation method. the fatty acid analyses indicated that type i mob most similar to species of methylomonas, methylomicrobium, and methylosarcina made a ... | 2005 | 16269705 |
| 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 |
| 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 |
| [stability of genetic markers in methane-oxidizing bacteria]. | a number of methylococcus thermophilus 111p clones have been obtained which have acquired resistance to tetracycline. the stability of maintenance of marker resistance in these clones and also in already designed methylomonas rubra 15sh mutants has been investigated. chromosomal markers resistance to antibiotics or formaldehyde were maintained in the marked strains methylococcus thermophilus 111p and methylomonas rubra 15sh after storage in nonselective conditions. the markers of resistance to a ... | 2002 | 12436866 |
| 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 |
| growth dynamics of a methylotroph (methylomonas l3) in continuous cultures. ii. growth inhibition and comparison against an unstructured model. | high methanol concentrations have a negative effect on the growth rate and the biomass yield of growth transients induced by methanol pulses in continuous cultures of methylomonas l3. the physiological basis of this effect is investigated by measuring the effect of the methanol pulse on the cell energy charge (ec) and atp, adp, and amp concentrations, and by comparing the results of the pulse transients against an unstructured model. the methanol pulse is shown to lead to increased values of the ... | 1987 | 18561130 |
| 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, ... | 2006 | 16461686 |
| identification and cloning of the gene encoding pyrophosphate-dependent 6-phosphofructokinase of methylomonas methanica. | | 2005 | 16480155 |
| 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 |
| effect of copper on methylomonas albus bg8. | addition of copper to the medium for methylomonas albus bg8 increased cell yield and methane monooxygenase activity. intracytoplasmic membrane was formed only in cells grown with copper supplementation. additionally, the abundances of two major membrane proteins were affected by copper in the growth medium. these findings indicate that effects of copper on the physiology of methanotrophic bacteria are not limited to those on types ii and x. | 1991 | 16348466 |
| 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 ... | 2006 | 16689866 |
| estimating high-affinity methanotrophic bacterial biomass, growth, and turnover in soil by phospholipid fatty acid 13c labeling. | a time series phospholipid fatty acid (plfa) 13c-labeling study was undertaken to determine methanotrophic taxon, calculate methanotrophic biomass, and assess carbon recycling in an upland brown earth soil from bronydd mawr (wales, united kingdom). laboratory incubations of soils were performed at ambient ch4 concentrations using synthetic air containing 2 parts per million of volume of 13ch4. flowthrough chambers maintained a stable ch4 concentration throughout the 11-week incubation. soils wer ... | 2006 | 16751495 |
| effects of temperature on methane consumption in a forest soil and in pure cultures of the methanotroph methylomonas rubra. | methane oxidation in soil cores from a mixed hardwood-coniferous forest varied relatively little as a function of incubation temperatures from -1 to 30 degrees c. the increase in oxidation rate was proportional to t (in kelvins). this relationship was consistent with limitation of methane transport through a soil gas phase to a subsurface zone of consumption by diffusion. the q(10) for co(2) production, 3.4, was substantially higher than that for methane oxidation, 1.1, and indicated that the re ... | 1992 | 16348766 |
| expression of bacterial hemoglobin genes to improve astaxanthin production in a methanotrophic bacterium methylomonas sp. | astaxanthin has been widely used as a feed supplement in poultry and aquaculture industries. one challenge for astaxanthin production in bacteria is the low percentage of astaxanthin in the total carotenoids. an obligate methanotrophic bacterium methylomonas sp. 16a was engineered to produce astaxanthin. astaxanthin production appeared to be dramatically affected by oxygen availability. we examined whether astaxanthin production in methylomonas could be improved by metabolic engineering through ... | 2007 | 17103157 |
| 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 |
| [classification of methylomonas rubra sp. nov]. | strain methylomonas rubra 15sh(t), deposited in several collections of microorganisms (ncimb 11913(t) = ucm b-3075(t) = acm 3303(t)), is the subject of numerous studies. however, the name of this strain is not valid, primarily due to the phenotypic similarity of the species m. rubra to the species m. methanica. the results of the present study and data available in the literature indicate that m. rubra deserves the status of a separate species. strains of m. rubra differ from strains of m. metha ... | 2006 | 17205804 |
| [effect of substances which change the proton-motive force on activity of methane microbe oxygenation]. | high extracellular concentration of k+ stimulated methane oxygenation with methylomonas rubra 15 [russian character: see text], methylococcus thermophilus 111 [russian character: see text] and methylococcus capsulatus 494 at neutral value of ph. that was determined by k+ arrival to the cells at neutral medium ph that resulted in the increase of ph difference between the exterior and interior sides of the membrane (aph) and, respectively, in the increase of the methane oxygenation rate. thus, met ... | 2006 | 17243361 |
| use of transposon promoter-probe vectors in the metabolic engineering of the obligate methanotroph methylomonas sp. strain 16a for enhanced c40 carotenoid synthesis. | the recent expansion of genetic and genomic tools for metabolic engineering has accelerated the development of microorganisms for the industrial production of desired compounds. we have used transposable elements to identify chromosomal locations in the obligate methanotroph methylomonas sp. strain 16a that support high-level expression of genes involved in the synthesis of the c(40) carotenoids canthaxanthin and astaxanthin. with three promoterless carotenoid transposons, five chromosomal locat ... | 2007 | 17261513 |
| [sequence analysis of 16s rdna and genes of soluble methane monooxygenase from methylomonas sp. gyj3]. | soluble methane monooxygenase (mmo) from methanotrophs is a member of binuclear iron-containing multicomponent oxygenases, which can catalyze bioconversion of methane to methanol at ambient temperature and regulate methane recycle in nature. the research focused mainly on the sequence analysis of 16s rdna and smmo genes from methylomonas sp. gyj3. with the aid of the information from genbank, the pcr primers and the sequence primers were designed, obtained a 5690bp of smmo fragment and a 1280bp ... | 2007 | 17436643 |
| [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 ... | 2006 | 16686213 |
| [comparative characterization of cultured methane-oxidizing bacteria by serological and molecular methods]. | three stable methane-oxidizing enrichment cultures, sb26, sb31, and sb31a were analyzed by transmission electron microscopy and by serological and molecular techniques. electron microscopy revealed the presence of both type i and type ii methanotrophs in sb31 and sb31a enrichments; only type ii methanotrophs were found in sb26 enrichment. methylosinus trichosporium was detected in all three enrichments by the application of species-specific antibodies. additionally, methylocystis echinoides was ... | 2006 | 16871808 |
| analysis of fae and fhcd genes in mono lake, california. | genes for two enzymes of the tetrahydromethanopterin-linked c(1) transfer pathway (fae and fhcd) were detected in hypersaline, hyperalkaline mono lake (california), via pcr amplification and analysis. low diversity for fae and fhcd was noted, in contrast to the diversity previously detected in a freshwater lake, lake washington (washington). | 2005 | 16332897 |
| construction of the astaxanthin biosynthetic pathway in a methanotrophic bacterium methylomonas sp. strain 16a. | methylomonas sp. strain 16a is an obligate methanotrophic bacterium that uses methane or methanol as the sole carbon source. an effort was made to engineer this organism for astaxanthin production. upon expressing the canthaxanthin gene cluster under the control of the native hps promoter in the chromosome, canthaxanthin was produced as the main carotenoid. further conversion to astaxanthin was carried out by expressing different combinations of crtw and crtz genes encoding the beta-carotenoid k ... | 2007 | 17205350 |
| 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 ... | 2005 | 16329925 |
| sources for sedimentary bacteriohopanepolyols as revealed by 16s rdna stratigraphy. | bacteriohopanoids are widespread lipid biomarkers in the sedimentary record. many aerobic and anaerobic bacteria are potential sources of these lipids which sometimes complicates the use of these biomarkers as proxies for ecological and environmental changes. therefore, we applied preserved 16s ribosomal rna genes to identify likely holocene biological sources of bacteriohopanepolyols (bhps) in the sulfidic sediments of the permanently stratified postglacial ace lake, antarctica. a suite of inta ... | 2008 | 18397311 |
| process optimization of a continuous airlift tower-loop reactor. | based on the experimental investigations with h. polymorpha and methylomonas m 15 in bench-scale airlift tower-loop reactors, a general distributed parameter model was developed and used to simulate to cultivation process in a 40-m-high production reactor. this general model was simplified with regard to the gas phase and loop balances and was employed to optimize cell productivity and/or profit in a 20-m-high pilot-plant airlift tower-loop reactor. maximum cell productivity always occurs in the ... | 1982 | 18548441 |
| 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 ... | 2007 | 17922768 |
| phylogenetic and functional gene analysis of the bacterial and archaeal communities associated with the surface microlayer of an estuary. | the surface microlayer (sml) is the thin biogenic film found at the surface of a water body. the sml is poorly understood but has been shown to be important in biogeochemical cycling and sea-air gas exchange. we sampled the sml of the blyth estuary at two sites (salinities 21 and 31 psu) using 47 mm polycarbonate membranes. dna was extracted from the sml and corresponding subsurface water (0.4 m depth) and microbial (bacteria and archaea) community analysis was performed using denaturing gradien ... | 2008 | 18356822 |
| growth dynamics of a methylotroph (methylomonas l3) in continuous cultures. i. fast transients induced by methanol pulses and methanol accumulation. | the dynamic behavior of the ribulose monophosphate-type methylomonas l3 in continuous cultures was studied, using methanol pulses to induce fast transients in steady-state cultures of single (methanol) and mixed (methanol plus formaldehyde) substrates. in several experiments, the methanol-uptake rate (mur) profiles displayed negative mur values for a time period following the methanol pulse, and significant amounts of methanol disappeared immediately following the pulse. these phenomena suggeste ... | 1987 | 18561129 |
| detection, isolation, and characterization of acidophilic methanotrophs from sphagnum mosses. | sphagnum peatlands are important ecosystems in the methane cycle. methane-oxidizing bacteria in these ecosystems serve as a methane filter and limit methane emissions. yet little is known about the diversity and identity of the methanotrophs present in and on sphagnum mosses of peatlands, and only a few isolates are known. the methanotrophic community in sphagnum mosses, originating from a dutch peat bog, was investigated using a pmoa microarray. a high biodiversity of both gamma- and alphaprote ... | 2011 | 21724892 |
| direct measurement of carbon substrate oxidation and incorporation patterns in rump-type methylotrophs: chemostatic cultures of methylomonas l3. | a technique using c-14 isotope tracers to probe the branching of carbon flow in methylotrophic bacteria has been devised and applied to continuous steady-state cultures. methylomonas l3, a strain which utilizes the kdpg/ta variant of the ribulose monophosphate cycle for carbon fixation, was employed in the experimental studies. the actual in vivo rates of substrate-carbon incorporation into biomass, both direct and via co(2), and of the two carbon oxidation schemes were determined in three diffe ... | 1985 | 18553623 |
| 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 ... | 2008 | 18607374 |
| use of bromodeoxyuridine immunocapture to identify psychrotolerant phenanthrene-degrading bacteria in phenanthrene-enriched polluted baltic sea sediments. | the aim of this study was to enrich and identify psychrotolerant phenanthrene-degrading bacteria from polluted baltic sea sediments. polyaromatic hydrocarbon (pah)-contaminated sediments were spiked with phenanthrene and incubated for 2 months in the presence of bromodeoxyuridine that is incorporated into the dna of replicating cells. the bromodeoxyuridine-incorporated dna was extracted by immunocapture and analyzed by terminal-restriction fragment length polymorphism and 16s rrna gene cloning a ... | 2008 | 18616589 |
| the methane monooxygenase intrinsic activity of kinds of methanotrophs. | methanotrophs have promising applications in the epoxidation of some alkenes and some chlorinated hydrocarbons and in the production of a biopolymer, poly-beta-hydroxybutyrate (poly-3-hydroxybutyrate; phb). in contrast with methane monooxygenase (mmo) activity and ability of phb synthesis of four kinds of methanotrophic bacteria methylosinus trichosporium ob3b, m. trichosporium imv3011, methylococcus capsulatus hd6t, methylomonas sp. gyj3, and the mixture of the four kinds of strains, m. trichos ... | 2009 | 19052919 |
| 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. | 2009 | 19054233 |
| cultural properties and mass-energy balances in methanol fermentation by methylomonas methanolovorans. | the cultural properties of an obligate methanol utilizer, methylomonas methanolovorans, were investigated in batch and continuous cultures, and the problems of mass-energy balances were examined. among the culture data, an exponential increase of growth lag with increased methanol concentration, as well as the inhibition kinetics in the relation between attainable maximum specific growth rate (mu(m) <== 0.52) and methanol concentration are of interest. in the latter case, the inhibition constant ... | 1983 | 18548603 |
| ammonia cometabolism and product inhibition vary considerably among species of methanotrophic bacteria. | ecological studies have indicated that relative abundances of gammaproteobacteria methanotrophs (gamma-mob) vs. alphaproteobacteria methanotrophs (alpha-mob) in nitrogen (n) impacted soils are dictated in part by their abilities to tolerate inhibitory effects of ammonium and nitrite. in particular, ammonia is a cometabolic substrate and competitive inhibitor of methane monooxygenase. the rates of ammonia and hydroxylamine oxidation and inhibition of methane-oxidizing activity by ammonium and nit ... | 2009 | 19566684 |
| influence of total and oxygen partial pressure on growth and metabolism of methylomonas clara. | the effect of total and oxygen partial pressure on metabolic activities of methylomonas clara has been investigated in batch and continuous cultivation experiments using a pressurizable airlift loop reactor. at oxygen partial pressures of more than 1000 mbar growth of m. clara is retarded and completely inhibited at 1200 mbr. however, after several hours of incubation at elevated oxygen partial pressures, biomass formation is nearly doubled in subsequent continuous operation, cells pretreated wi ... | 1992 | 18601172 |
| nutrient removal and bacterial communities in swine wastewater lagoon and constructed wetlands. | surface constructed wetlands, including marsh-pond-marsh (mpm) and continuous marsh (ctm) were used to treat swine wastewater in this study. the objectives of this research were to evaluate the surface constructed wetland effects on swine wastewater treatment, and to investigate bacterial distribution shifts along treatment flows. water quality parameters and bacterial community diversity were analyzed in each section of the entire wastewater treatment system, which was from the anaerobic lagoon ... | 2010 | 20700852 |
| [effect of plant-associated methanolic bacteria on methane and methanol concentration dynamics in atmosphere of pressurized chamber]. | stability of chinese cabbage crop colonization by methanolic bacteria methylovorus mays, methylomonas methanica and methylosinus trichosporium inoculated using a space-applicable method was evaluated. besides, trends of methane and methanol concentrations in the pressurized chamber with inoculated and uninoculated crops were calculated. methylovorus mays and methylosinus trichosporium were shown to establish more stable colonization as compared to methylomonas methanica. also, stable association ... | 2010 | 20804000 |
| rice roots select for type i methanotrophs in rice field soil. | methanotrophs are an important regulator for reducing methane (ch(4)) emissions from rice field soils. the type i group of the proteobacterial methanotrophs are generally favored at low ch(4) concentration and high o(2) availability, while the type ii group lives better under high ch(4) and limiting o(2) conditions. such physiological differences are possibly reflected in their ecological preferences. in the present study, methanotrophic compositions were compared between rice-planted soil and n ... | 2009 | 19481894 |
| effect of temperature and pressure on growth and methane utilization by several methanotrophic cultures. | several methanotrophic microorganisms, i.e., methylococcus capsulatus (bath), methylomonas albus (bg-8), methylosinus trichosporium ob3b, and methylocystis parvus (obbp), were evaluated for growth and methane utilization. the effect of temperature was examined in the range of 25 to 45 degrees c for growth and methane utilization. the temperature variations (25-35 degrees c) had minimal effect on growth of m. albus and m. parvus. methane consumption varied at different temperatures with a maximum ... | 1998 | 18576037 |
| [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 ... | 2011 | 21598653 |
| improvement of a crto-type of beta-carotene ketolase for canthaxanthin production in methylomonas sp. | two types of non-homologous beta-carotene ketolases (crtw and crto) were previously described. we report improvement of a crto-type of beta-carotene ketolase for canthaxanthin production in a methylotrophic bacterium, methylomonas sp. 16a, which could use the c1 substrate (methane or methanol) as sole carbon and energy source. the crto gene from rhodococcus erythropolis was improved for canthaxanthin production in an e. coli strain engineered to produce high titer carotenoids by error-prone pcr ... | 2007 | 17627860 |
| 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 ... | 2007 | 17714486 |
| characterization of recombinant pyrophosphate-dependent 6-phosphofructokinase from halotolerant methanotroph methylomicrobium alcaliphilum 20z. | pyrophosphate-dependent 6-phosphofructokinase (ppi-pfk) was obtained as his₆-tagged protein by cloning of the pfp gene from the aerobic obligate methanotroph methylomicrobium alcaliphilum 20z and characterized. the recombinant ppi-pfk (4×45 kda) was highly active, non-allosteric and stringently specific to pyrophosphate as the phosphoryl donor. the enzyme was more specific for the reverse reaction substrate fructose-1,6-bisphosphate (k(m) 0.095 mm, v(max) 805 u/mg of protein) than for the forwar ... | 2010 | 20868748 |
| 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 ... | 2011 | 21925596 |
| seasonal change in methanotrophic diversity and populations in a rice field soil assessed by dna-stable isotope probing and quantitative real-time pcr. | the community structure of methane-oxidizing bacteria (methanotrophs) is affected by concentrations of methane and oxygen. in rice fields, concentrations of both gases differ significantly between the flooded and drained seasons. we investigated the active methanotrophic community structures in flooded and drained soils by dna-based stable isotope probing. active methanotrophic diversity was assessed with clone library-based analyses of the 16s rrna gene and the particulate methane monooxygenase ... | 2010 | 21576868 |
| the impact of aridification and vegetation type on changes in the community structure of methane-cycling microorganisms in japanese wetland soils. | over the years, the wetlands covered by sphagnum in bibai, japan have been turning into areas of aridity, resulting in an invasion of sasa into the bogs. yet little is known about the methane-cycling microorganisms in such environments. in this study, the methanotrophic, methanogenic, and archaeal community structures within these two types of wetland vegetation were studied by phylogenetic analysis targeting particulate methane monooxygenase (pmoa), methyl coenzyme m reductase (mcra), and the a ... | 2011 | 21897040 |
| methylomonas koyamae sp. nov., a type i methane-oxidizing bacterium from floodwater of a rice paddy field in japan. | a novel methane-oxidizing bacterium, strain fw12e-y(t), was isolated from floodwater of a rice paddy field in japan. cells of strain fw12e-y(t) are gram-negative, motile rods with single polar flagellum and type i intracytoplasmic membrane arrangement. the strain grows only on methane or methanol as the sole carbon and energy source. it grows at 10-40°c (optimum 30°c), ph 5.5-7.0 (optimum 6.5) and with 0-0.1% (w/w) nacl (no growth above 0.5%). sequence analysis of 16s rrna gene showed that the s ... | 2011 | 21984674 |
| 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 ... | 2004 | 19712303 |
| miniaturized extinction culturing is the preferred strategy for rapid isolation of fast-growing methane-oxidizing bacteria. | methane-oxidizing bacteria (mob) have a large potential as a microbial sink for the greenhouse gas methane as well as for biotechnological purposes. however, their application in biotechnology has so far been hampered, in part due to the relative slow growth rate of the available strains. to enable the availability of novel strains, this study compares the isolation of mob by conventional dilution plating with miniaturized extinction culturing, both performed after an initial enrichment step. th ... | 2011 | 22070783 |
| complete genome sequence of the aerobic marine methanotroph methylomonas methanica mc09. | methylomonas methanica mc09 is a mesophilic, halotolerant, aerobic, methanotrophic member of the gammaproteobacteria, isolated from coastal seawater. here we present the complete genome sequence of this strain, the first available from an aerobic marine methanotroph. | 2011 | 22123758 |