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hydrogen-oxidizing methane bacteria. ii. electron microscopy.comparison of the fine structure of the methanogenic organism from the culture known as methanobacillus omelianskii with that of methanobacterium formicicum revealed a great similarity. both organisms exhibited a large number of intracytoplasmic membranous elements when stained with phosphotungstic acid. in contrast, no such elements were observed in methanobacterium ruminantium.19685643051
occurrence of purple sulfur bacteria in a sewage treatment lagoon.the ecology of purple sulfur bacteria in a sewage oxidation lagoon was investigated. chemical changes in the lagoon were investigated by monitoring biochemical oxygen demand (bod(5)), sulfide, sulfate, phosphate, total carbohydrates, volatile acids, alkalinity, and ph. lagoon water temperatures were observed daily. microbial ecological relationships were deduced by enumerating coliforms, total bacteria other than anaerobes [tryptone glucose extract (tge) agar], methane formers such as methanobac ...19704917194
new method for the isolation and identification of methanogenic bacteria.a new technique is reported for the rapid growth and detection of methanogenic bacteria by using petri plates. the method employs an anaerobic glove box containing an inner chamber with separate gas-flushing facilities. the numbers of methanogenic bacteria recovered from domestic sewage sludge are comparable to those recovered by other methods. the methanogenic organisms isolated from sludge include methanosarcina, methanospirillum, methanobacterium strain m.o.h., and methanobacterium formicicum ...1975804855
growth of desulfovibrio in lactate or ethanol media low in sulfate in association with h2-utilizing methanogenic bacteria.in the analysis of an ethanol-co(2) enrichment of bacteria from an anaerobic sewage digestor, a strain tentatively identified as desulfovibrio vulgaris and an h(2)-utilizing methanogen resembling methanobacterium formicicum were isolated, and they were shown to represent a synergistic association of two bacterial species similar to that previously found between s organism and methanobacterium strain moh isolated from methanobacillus omelianskii. in lowsulfate media, the desulfovibrio produced ac ...1977879775
application of the fluorescent-antibody technique to the study of a methanogenic bacterium in lake sediments.fluorescent antibody (fa) was prepared for a methanogenic bacterium isolated from wintergreen lake pelagic sediment. the isolate resembles methanobacterium formicicum. the fa did not cross-react with 9 other methanogens, including m. formicicum strains, or 24 heterotrophs, 18 of which had been isolated from wintergreen lake sediment. fa-reacting methanogens were detected in heat-fixed smears of several different lake sediments and anaerobic sewage sludge. pretreatment of all samples with either ...1978341807
effect of monensin and lasalocid-sodium on the growth of methanogenic and rumen saccharolytic bacteria.it is thought that monensin increases the efficiency of feed utilization by cattle by altering the rumen fermentation. we studied the effect of monensin and the related ionophore antibiotic lasalocid-sodium (hoffman-laroche) on the growth of methanogenic and rumen saccharolytic bacteria in a complex medium containing rumen fluid. ruminococcus albus, ruminococcus flavefaciens, and butyrivibrio fibrisolvens were inhibited by 2.5 mug of monensin or lasalocid per ml. growth of bacteroides succinogen ...197916345418
metabolism of formate in methanobacterium formicicum.methanobacterium formicicum strain jf-1 was cultured with formate as the sole energy source in a ph-stat fermentor. growth was exponential, and both methane production and formate consumption were linear functions of the growth rate. hydrogen was produced in only trace amounts, and the dissolved h(2) concentration of the culture medium was below 1 mum. the effect of temperature or ph on the rate of methane formation was studied with a single fermentor culture in mid-log phase that was grown with ...19806769911
methane formation from fructose by syntrophic associations of acetobacterium woodii and different strains of methanogens.when acetobacterium woodii was co-cultured in continuous or in stationary culture with methanobacterium strain az, fructose instead of being converted to 3 mol of acetate was converted to 2 mol of acetate and 1 mol each of carbon dioxide and methane, showing that interspecies hydrogen transfer occurred. in continuous culture the organisms formed a close physical association in clumps; the doubling time for each organism was 6 h at 33 degrees c. methane mainly was derived from carbon positions 3 ...19806769417
influence of corrinoid antagonists on methanogen metabolism.iodopropane inhibited cell growth and methane production when methanobacterium thermoautotrophicum, methanobacterium formicicum, and methanosarcina barkeri were cultured on h2-co2. iodopropane (40 microm) inhibited methanogenesis (30%) and growth (80%) when m. barkeri was cultured mixotrophically on h2-co2-methanol. the addition of acetate to the medium prevented the observed iodopropane-dependent inhibition of growth. the concentrations of iodopropane that caused 50% inhibition of growth of m. ...19816783613
properties of formate dehydrogenase in methanobacterium formicicum.soluble formate dehydrogenase from methanobacterium formicicum was purified 71-fold with a yield of 35%. purification was performed anaerobically in the presence of 10 mm sodium azide which stabilized the enzyme. the purified enzyme reduced, with formate, 50 mumol of methyl viologen per min per mg of protein and 8.2 mumol of coenzyme f420 per min per mg of protein. the apparent km for 7,8-didemethyl-8-hydroxy-5-deazariboflavin, a hydrolytic derivative of coenzyme f420, was 10-fold greater (63 mi ...19827061389
kinetics of formate metabolism in methanobacterium formicicum and methanospirillum hungatei.the kinetics of formate metabolism in methanobacterium formicicum and methanospirillum hungatei were studied with log-phase formate-grown cultures. the progress of formate degradation was followed by the formyltetrahydrofolate synthetase assay for formate and fitted to the integrated form of the michaelis-menten equation. the k(m) and v(max) values for methanobacterium formicicum were 0.58 mm formate and 0.037 mol of formate h g (dry weight), respectively. the lowest concentration of formate met ...198216346087
fad requirement for the reduction of coenzyme f420 by formate dehydrogenase from methanobacterium formicicum.the partial purification of the formate dehydrogenase from cell-free extracts of methanobacterium formicicum decreased the rate of coenzyme f420 reduction 175-fold relative to the rate of methyl viologen reduction. fad, isolated from this organism, reactivated the coenzyme f420-dependent activity of purified formate dehydrogenase and restored the activity ratio (coenzyme f420/methyl viologen) to near that in cell-free extracts. neither flavin mononucleotide nor fadh2 replaced fad. the reduced fo ...19836874636
evidence for formation of superoxide and formate radicals in methanobacterium formicicum.using spin labeling and spin trapping techniques in combination with electron paramagnetic resonance spectrometry, we have detected the formation of superoxide by whole cells of methanobacterium formicicum under aerobic conditions in the presence and absence of sodium formate. rates of superoxide generation have been estimated. the formation of additional free radical species, including formate, was observed. production of these and other free radicals resulted in lipid peroxidation and concomit ...19836298181
formate dehydrogenase from methanobacterium formicicum. electron paramagnetic resonance spectroscopy of the molybdenum and iron-sulfur centers.formate dehydrogenase from methanobacterium formicicum was examined by electron paramagnetic resonance spectroscopy. although oxidized enzyme yielded no epr signals over the temperature range 8-200 k, dithionite reduction resulted in generation of two paramagnetic components. the first, a nearly isotropic signal visible at temperatures below 200 k with g1 = 2.018, g2 = 2.003, and g3 = 1.994, exhibited nuclear hyperfine interaction with two equivalent protons (a1 = 0.45, a2 = 0.6, and a3 = 0.55 m ...19836309816
carbon monoxide-dependent methyl coenzyme m methylreductase in acetotrophic methosarcina spp.cell extracts of acetate-grown methanosarcina strain tm-1 and methanosarcina acetivorans both contained ch3-s-com methylreductase activity. the methylreductase activity was supported by co and h2 but not by formate as electron donors. the co-dependent activity was equivalent to the h2-dependent activity in strain tm-1 and was fivefold higher than the h2-dependent activity of m. acetivorans. when strain tm-1 was cultured on methanol, the co-dependent activity was reduced to 5% of the activity in ...19846501214
fad requirement for the reduction of coenzyme f420 by hydrogenase from methanobacterium formicicum.hydrophobic interaction chromatography of coenzyme f420-reducing hydrogenase purified from methanobacterium formicicum depleted protein-bound fad and eliminated the ability to reduce coenzyme f420. preincubation of the fad-depleted hydrogenase with fad restored 85% of the coenzyme f420-reducing activity. fmn did not replace fad. a kd of 12 microm was estimated for fad. analysis of the reactivated hydrogenase following molecular sieve column chromatography showed that fad was bound to protein. th ...19846375661
methanogenesis from sucrose by defined immobilized consortia.a bacterial consortium capable of sucrose degradation primarily to ch(4) and co(2) was constructed, with acetate as the key methanogenic precursor. in addition, the effect of agar immobilization on the activity of the consortium was determined. the primary fermentative organism, escherichia coli, produced acetate, formate, h(2), and co(2) (known substrates for methanogens), as well as ethanol and lactate, compounds that are not substrates for methanogens. oxidation of the nonmethanogenic substra ...198416346452
effect of monensin on growth and methanogenesis of methanobacterium formicicum.monensin inhibited methanogenesis from formate but not from h(2)-co(2) by resting-cell suspensions of methanobacterium formicicum. the antibiotic severely inhibited growth on formate. the lag phase of h(2)-co(2)-grown cultures was prolonged by monensin, but these cultures recovered from the initial inhibition. the recovery did not result from the development of a monensin-resistant population or inactivation of the antibiotic.198416346634
studies of the gtpase domain of archaebacterial ribosomes.ribosomes from the methanogens methanococcus vannielii and methanobacterium formicicum catalyse uncoupled hydrolysis of gtp in the presence of factor ef-2 from rat liver (but not factor ef-g from escherichia coli). in this assay, and in poly(u)-dependent protein synthesis, they were sensitive to thiostrepton. in contrast, ribosomes from sulfolobus solfataricus did not respond to factor ef-2 (or factor ef-g) but possessed endogenous gtpase activity, which was also sensitive to thiostrepton. ribos ...19852411554
enzymatic lysis of the pseudomurein-containing methanogen methanobacterium formicicum.a streptomycete isolated from cow manure produces an extracellular enzyme capable of lysing the pseudomurein-containing methanogen methanobacterium formicicum. the lytic activity has been partially purified from culture fluid and appears to be a serine protease. similar lytic activity has been fractionated from pronase. optimal conditions have been developed for lysis of m. formicicum by commercial preparations of proteinase k. the three lytic enzymes have been partially characterized. the resul ...19853891731
mechanistic studies of the coenzyme f420 reducing formate dehydrogenase from methanobacterium formicicum.mechanistic studies have been undertaken on the coenzyme f420 dependent formate dehydrogenase from methanobacterium formicicum. the enzyme was specific for the si face hydride transfer to c5 of f420 and joins three other f420-recognizing methanogen enzymes in this stereospecificity, consistent perhaps with a common type of binding site for this 8-hydroxy-5-deazariboflavin. while catalysis probably occurs by hydride transfer from formate to the enzyme to generate an eh2 species and then by hydrid ...19863801411
composition of the coenzyme f420-dependent formate dehydrogenase from methanobacterium formicicum.the coenzyme f420-dependent formate dehydrogenase from methanobacterium formicicum was purified to electrophoretic homogeneity by anoxic procedures which included the addition of azide, flavin adenine dinucleotide (fad), glycerol, and 2-mercaptoethanol to all buffer solutions to stabilize activity. the enzyme contains, in approximate molar ratios, 1 fad molecule and 1 molybdenum, 2 zinc, 21 to 24 iron, and 25 to 29 inorganic sulfur atoms. denaturation of the enzyme released a molybdopterin cofac ...19863944055
molybdopterin cofactor from methanobacterium formicicum formate dehydrogenase.the molybdopterin cofactor from the formate dehydrogenase of methanobacterium formicicum was studied. the cofactor was released by guanidine denaturation of homogeneous enzyme, which also released greater than 80% of the molybdenum present in the enzyme. the anoxically isolated cofactor was nonfluorescent, but after exposure to air it fluoresced with spectra similar to those of described molybdopterin cofactors. aerobic release from acid-denatured formate dehydrogenase in the presence of i2 and ...19863700335
cloning, expression, and nucleotide sequence of the formate dehydrogenase genes from methanobacterium formicicum.the genes for the two subunits of the formate dehydrogenase from methanobacterium formicicum were cloned and their sequences determined. when expressed in escherichia coli, two proteins were produced which had the appropriate mobility on an sds gel for the two subunits of formate dehydrogenase and cross-reacted with antibodies raised to purified formate dehydrogenase. the genes for the two formate dehydrogenase subunits overlap by 1 base pair and are preceded by dna sequences similar to both eub ...19863531194
arthropathic properties of cell wall polymers from normal flora bacteria.peptidoglycan-polysaccharide (pg-ps) fragments were purified from cell walls of group d streptococci (streptococcus faecium, strains atcc 9790 and f-24) with a protocol which minimizes autolytic activity and tested for ability to induce arthritis in rats. pg-ps fragments from cell walls of other normal flora bacteria (peptostreptococcus productus, and propionibacterium acnes), group a streptococci, and pseudomurein-ps fragments from cell walls of methanobacterium formicicum, were similarly purif ...19863940996
microbial ecophysiology of whey biomethanation: characterization of bacterial trophic populations and prevalent species in continuous culture.the organization and species composition of bacterial trophic groups associated with lactose biomethanation were investigated in a whey-processing chemostat by enumeration, isolation, and general characterization studies. the bacteria were spatially organized as free-living forms and as self-immobilized forms appearing in flocs. three dominant bacterial trophic group populations were present (in most probable number per milliliter) whose species numbers varied with the substrate consumed: hydrol ...198616346970
inhibition of methanogenesis in pure cultures by ammonia, fatty acids, and heavy metals, and protection against heavy metal toxicity by sewage sludge.the effect of ammonium chloride, sodium butyrate, sodium propionate, and the heavy metals nickel, zinc, and copper on methanogenesis by pure cultures of methanospirillum hungatei, methanosarcina barkeri, methanobacterium thermoautotrophicum, and methanobacterium formicicum at ph 6.5 was studied. the latter three strains were resistant to greater than 60 g/l of the volatile fatty acids and to greater than 10 g/l of nh3 n. methanospirillum hungatei was somewhat more sensitive with 50% inhibition o ...19873621086
locations of the hydrogenases of methanobacterium formicicum after subcellular fractionation of cell extract.the f420 hydrogenase of methanobacterium formicicum was associated with membranes isolated by sucrose density gradient ultracentrifugation of cell extract. the methyl viologen hydrogenase was present in the soluble fractions. column chromatography with phenyl-sepharose cl-4b revealed that the f420 hydrogenase was strongly hydrophobic, suggesting that it associates with isolated membranes through hydrophobic interactions.19873301819
purification and properties of formate dehydrogenase from pseudomonas aeruginosa. electron-paramagnetic-resonance studies on the molybdenum centre.formate dehydrogenase from pseudomonas aeruginosa contains molybdenum, a [4fe-4s] cluster and cytochrome b. this paper reports the detection of molybdenum as mo(v) by e.p.r. spectroscopy. in order to generate mo(v) signals, addition of amounts of excess formate varying between 10- and 50-fold over enzyme, followed by 200-fold excess of sodium dithionite, were used. two mo(v) species were observed. one, the major component, has g1 = 2.012, g2 = 1.985 and g3 = 1.968, appeared at low concentrations ...19873038082
microbial ecophysiology of whey biomethanation: comparison of carbon transformation parameters, species composition, and starter culture performance in continuous culture.changes in lactose concentration and feed rate altered bacterial growth and population levels in a whey-processing chemostat. the bacterial population and methane production levels increased in relation to increased lactose concentrations comparable to those in raw whey (6%) and converted over 96% of the substrate to methane, carbon dioxide, and cells. sequential increases in the chemostat dilution rate demonstrated excellent biomethanation performance at retention times as low as 25 h. retentio ...198716347341
methanogen factor 390 formation: species distribution, reversibility and effects of non-oxidative cellular stresses.factor 390 (f390), an adenylylated or guanylylated derivative of the methanogen coenzyme factor 420 (f420), was previously detected in methanobacterium thermoautotrophicum cells exposed to air. of six other methanogenic species that have now been tested, only methanobacterium formicicum was found to produce f390 upon oxygen exposure. aerobic conditions led to an immediate cessation of methanogenesis, whereas only 51% of cellular f420 was slowly converted to f390 over 4 h in mb.formicicum at 37 d ...19882855706
characterization of the upstream region of the formate dehydrogenase operon of methanobacterium formicicum.the fdha and fdhb genes of methanobacterium formicicum, which code for the alpha and beta subunits of formate dehydrogenase, were cotranscribed as part of a large transcript. by using northern (rna) gel blot analysis, the transcription start site was located within a 1.6-kilobase bglii-ncoi fragment 4.3 kilobases upstream from the fdha gene. the precise transcription start site within the fragment was determined with the aid of primer extension analysis and s1 nuclease protection studies. a puta ...19882457012
effect of molybdenum and tungsten on synthesis and composition of formate dehydrogenase in methanobacterium formicicum.the influence of sodium molybdate and sodium tungstate on formate dehydrogenase activity was studied in h2-co2-grown cultures of methanobacterium formicicum. depletion of molybdate from the growth medium resulted in a 75-fold decrease of intracellular molybdenum and a 35-fold decrease in enzyme activity; however, growth rate and cell yields were not influenced. by using an indirect enzyme-linked immunoassay, the amount of formate dehydrogenase approximated 3% of the total protein in cells grown ...19882457011
control of interspecies electron flow during anaerobic digestion: significance of formate transfer versus hydrogen transfer during syntrophic methanogenesis in flocs.microbial formate production and consumption during syntrophic conversion of ethanol or lactate to methane was examined in purified flocs and digestor contents obtained from a whey-processing digestor. formate production by digestor contents or purified digestor flocs was dependent on co(2) and either ethanol or lactate but not h(2) gas as an electron donor. during syntrophic methanogenesis, flocs were the primary site for formate production via ethanol-dependent co(2) reduction, with a formate ...198816347526
quantitative immunologic analysis of the methanogenic flora of digestors reveals a considerable diversity.to determine which methanogens occur in digestors, we performed a quantitative immunologic analysis of a variety of samples. a comprehensive panel of calibrated polyclonal antibody probes of predefined specificity spectra was used. this allowed precise identification of bacteria by antigenic fingerprinting. a considerable diversity of methanogens was uncovered, much larger than previously reported, encompassing at least 14 strains of 11 species. strategies were developed to measure the load of a ...198816347541
direct characterization of methanogens in two high-rate anaerobic biological reactors.the methanogenic flora from two types of turbulent, high-rate reactors was studied by immunologic methods as well as by phase-contrast, fluorescence, and scanning electron microscopy. the reactors were a fluidized sand-bed biofilm anitron reactor and an ultrafiltration membrane-associated suspended growth mars reactor (both trademarks of air products and chemicals, inc., allentown, pa.). conventional microscopic methods revealed complex mixtures of microbes of a range of sizes and shapes, among ...198816347581
isolation and characterization of methanogenic bacteria from landfills.methanogenic bacteria were isolated from landfill sites in the united kingdom. strains of methanobacterium formicicum, methanosarcina barkeri, several different immunotypes of methanobacterium bryantii, and a coccoid methanogen distinct from the reference immunotypes were identified.198816347591
diffusion of the interspecies electron carriers h(2) and formate in methanogenic ecosystems and its implications in the measurement of k(m) for h(2) or formate uptake.we calculated the potential h(2) and formate diffusion between microbes and found that at h(2) concentrations commonly found in nature, h(2) could not diffuse rapidly enough to dispersed methanogenic cells to account for the rate of methane synthesis but formate could. our calculations were based on individual organisms dispersed in the medium, as supported by microscopic observations of butyrate-degrading cocultures. we isolated an axenic culture of syntrophomonas wolfei and cultivated it on bu ...198916347966
shifts in methanogenic subpopulations measured with antibody probes in a fixed-bed loop anaerobic bioreactor treating sulfite evaporator condensate.a fixed-bed loop, high-rate anaerobic bioreactor treating sulfite evaporator condensate was sampled when it reached steady state and afterwards following perturbations during a 14-month period. by using immunotechnology, it was observed that shifts in methanogenic subpopulations occurred in association with perturbations, such as restarting and relocating the biomass into a different tank. methanogens related to methanobacterium bryantii mohg and methanobrevibacter smithii ali were numerous thro ...198916347990
nucleotide sequence of the glyceraldehyde-3-phosphate dehydrogenase gene from the mesophilic methanogenic archaebacteria methanobacterium bryantii and methanobacterium formicicum. comparison with the respective gene structure of the closely related extreme thermophile methanothermus fervidus.the genes for glyceraldehyde-3-phosphate dehydrogenase (gap genes) from the mesophilic methanogenic archaebacteria methanobacterium formicicum and methanobacterium bryantii were cloned and sequenced. the deduced amino acid sequences show 95% identity to each other and about 70% identity to the glyceraldehyde-3-phosphate dehydrogenase from the thermophilic methanogenic archaebacterium methanothermus fervidus. although the sequence similarity between the archaebacterial glyceraldehyde-3-phosphate ...19892492940
purification and properties of the membrane-associated coenzyme f420-reducing hydrogenase from methanobacterium formicicum.the membrane-associated coenzyme f420-reducing hydrogenase of methanobacterium formicicum was purified 87-fold to electrophoretic homogeneity. the enzyme contained alpha, beta, and gamma subunits (molecular weights of 43,000, 36,700, and 28,800, respectively) and formed aggregates (molecular weight, 1,020,000) of a coenzyme f420-active alpha 1 beta 1 gamma 1 trimer (molecular weight, 109,000). the hydrogenase contained 1 mol of flavin adenine dinucleotide (fad), 1 mol of nickel, 12 to 14 mol of ...19892738024
reconstitution and properties of a coenzyme f420-mediated formate hydrogenlyase system in methanobacterium formicicum.formate hydrogenlyase activity in a cell extract of methanobacterium formicicum was abolished by removal of coenzyme f420; addition of purified coenzyme f420 restored activity. formate hydrogenlyase activity was reconstituted with three purified components from m. formicicum: coenzyme f420-reducing hydrogenase, coenzyme f420-reducing formate dehydrogenase, and coenzyme f420. the reconstituted system required added flavin adenine dinucleotide (fad) for maximal activity. without fad, the formate d ...19892661536
glyceraldehyde-3-phosphate dehydrogenase from the hyperthermophilic archaebacterium pyrococcus woesei: characterization of the enzyme, cloning and sequencing of the gene, and expression in escherichia coli.the glyceraldehyde-3-phosphate dehydrogenase from the hyperthermophilic archaebacterium pyrococcus woesei (optimal growth temperature, 100 to 103 degrees c) was purified to homogeneity. this enzyme was strictly phosphate dependent, utilized either nad+ or nadp+, and was insensitive to pentalenolactone like the enzyme from the methanogenic archaebacterium methanothermus fervidus. the enzyme exhibited a considerable thermostability, with a 44-min half-life at 100 degrees c. the amino acid sequence ...19902165475
biosynthesis of methanopterin.the biosynthetic pathway for the generation of the methylated pterin in methanopterins was determined for the methanogenic bacteria methanococcus volta and methanobacterium formicicum. extracts of m. volta were found to readily cleave l-7,8-dihydroneopterin to 7,8-dihydro-6-(hydroxymethyl)pterin, which was confirmed to be a precursor of the pterin portion of the methanopterin. [methylene-2h]-6-(hydroxymethyl)pterin was incorporated into methanopterin by growing cells of m. volta to an extent of ...19902383552
performance of trickle-bed bioreactors for converting synthesis gas to methane.carbon monoxide, h2, and co2 in synthesis gas can be converted to ch4 by employing a triculture of rhodospirillum rubrum, methanosarcina barkeri, and methanobacterium formicicum. trickle-bed reactors have been found to be effective for this conversion because of their high mass-transfer coefficients. this paper compares results obtained for the conversion of synthesis gas to ch4 in 5-cm- and 16.5-cm-diameter trickle-bed reactors. mass-transfer and scale-up parameters are defined, and light requi ...19911929378
cloning and nucleotide sequence of the structural genes encoding the formate dehydrogenase of wolinella succinogenes.the formate dehydrogenase of wolinella succinogenes is a membraneous molybdo-enzyme which is involved in phosphorylative electron transport. the gene (fdha) encoding the largest subunit was isolated from a gene bank by immunological screening. the fdha gene was located in an apparent transcriptional unit (fdha,b,c,d) together with three more structural genes. the n-terminal sequences of three polypeptides present in the isolated enzyme were found to map within the fdha, b and c structural genes. ...19911781728
identification of molybdopterin guanine dinucleotide in formate dehydrogenase from methanobacterium formicicum.the pterin cofactor in formate dehydrogenase isolated from methanobacterium formicium is identified as molybdopterin guanine dinucleotide. the pterin, stabilized as the alkylated, dicarboxamidomethyl derivative, is shown to have absorption and chromatographic properties identical to those of the previously characterized authentic compound. treatment with nucleotide pyrophosphatase produced the expected degradation products gmp and carboxyamidomethyl molybdopterin. the molybdopterin guanine dinuc ...19912037231
the use of rrna sequences and fluorescent probes to investigate the phylogenetic positions of the anaerobic ciliate metopus palaeformis and its archaeobacterial endosymbiont.the polymerase chain reaction (pcr) was used to amplify small-subunit ribosomal dna from the anaerobic ciliated protozoon metopus palaeformis, and from its uncultured endosymbiotic bacteria. this was accomplished directly from total dna extracted from protozoa without prior isolation or enrichment for symbiont cells. the double-stranded amplification products were precipitated and directly sequenced using the linear pcr reaction. fluorescent oligonucleotide probes were designed and used in whole ...19921512578
identification of formate dehydrogenase-specific mrna species and nucleotide sequence of the fdhc gene of methanobacterium formicicum.the overlapping fdha and fdhb genes of methanobacterium formicicum, which encode the alpha and beta subunits, respectively, of formate dehydrogenase, were cotranscribed as part of an approximately 4.5-kb transcript. an additional gene (fdhc) upstream of fdha was cotranscribed with fdha and fdhb. the deduced amino acid sequence suggested that fdhc has the potential to encode a hydrophobic polypeptide with a calculated molecular weight of 29,417. a hydropathy plot of the hypothetical polypeptide i ...19921378430
effect of coculture of anaerobic fungi isolated from ruminants and non-ruminants with methanogenic bacteria on cellulolytic and xylanolytic enzyme activities.neocallimastix strain n1, an isolate from a ruminant (sheep), was cocultured with three methanobacterium formicicum strains, methanosarcina barkeri, and methanobrevibacter smithii. the coculture with methanobacterium formicicum strains resulted in the highest production of cellulolytic and xylanolytic enzymes. subsequently four anaerobic fungi, two neocallimastix strains (n1 and n2) from a ruminant and two piromyces species from non-ruminants (e2 and r1), were grown in coculture with methanobact ...19921550443
targeted insertion of selenocysteine into the alpha subunit of formate dehydrogenase from methanobacterium formicicum.selenocysteine incorporation into proteins is directed by an opal (uga) codon and requires the existence of a stem-loop structure in the mrna flanking the uga at its 3' side. to analyze the sequence and secondary-structure requirements for uga decoding, we have introduced mutations into the fdha gene from methanobacterium formicicum, which codes for the alpha subunit of the f420-reducing formate dehydrogenase. the m. formicicum enzyme contains a cysteine residue at the position where the escheri ...19921531049
anaerobic degradation of normal- and branched-chain fatty acids with four or more carbons to methane by a syntrophic methanogenic triculture.syntrophic degradation of normal- and branched-chain fatty acids with 4 to 9 carbons was investigated with a mesophilic syntrophic isobutyrate-butyrate-degrading triculture consisting of the non-spore-forming, syntrophic, fatty acid-degrading, gram-positive rod-shaped strain ib, methanobacterium formicicum t1n, and methanosarcina mazei t18. this triculture converted butyrate and isobutyrate to methane and converted valerate and 2-methylbutyrate to propionate and methane. this triculture also deg ...199416349311
anaerobic degradation of propionate by a mesophilic acetogenic bacterium in coculture and triculture with different methanogens.a mesophilic acetogenic bacterium (mpob) oxidized propionate to acetate and co(2) in cocultures with the formate- and hydrogen-utilizing methanogens methanospirillum hungatei and methanobacterium formicicum. propionate oxidation did not occur in cocultures with two methanobrevibacter strains, which grew only with hydrogen. tricultures consisting of mpob, one of the methanobrevibacter strains, and organisms which are able to convert formate into h(2) plus co(2) (desulfovibrio strain g11 or the ho ...199416349350
isolation and characterization of hypophosphite--resistant mutants of escherichia coli: identification of the foca protein, encoded by the pfl operon, as a putative formate transporter.hypophosphite was used as a toxic analogue to identify genes whose products have a putative function in the transport of formate. two tn10-derived insertion mutants were identified that exhibited increased resistance to high concentrations of hypophosphite in the culture medium. the transposon was located in the identical position in the foca (formate channel; previously termed orf) gene of the pfl operon in both mutants. a defined chromosomal foca nonsense mutant, which showed minimal polarity ...19948022272
methanobacterium formicicum, a mesophilic methanogen, contains three hfo histones.the mesophilic methanogen methanobacterium formicicum jf-1 has been shown to contain three members of the hmf family of archaeal histones, designated hfoa1, hfoa2, and hfob, and their encodinig genes (hfoa1, hfoa2, and hfob) have been cloned and sequenced. the hfo histones have primary sequences that are 75 to 82% identical to the hmf sequences and appear to share ancestry with the core histones that form the eukaryal nucleosome. the hfo proteins bind and compact dna molecules into nucleosome-li ...19957836329
a pao1-encoded molybdopterin cofactor gene (moaa) of arthrobacter nicotinovorans: characterization and site-directed mutagenesis of the encoded protein.a gene homologous to moaa, the gene responsible for the expression of a protein involved in an early step in the synthesis of the molybdopterin cofactor of escherichia coli, was found to be located 2.7-kb upstream of the nicotine dehydrogenase (ndh) operon on the catabolic plasmid pao1 of arthrobacter nicotinovorans. the moaa protein, containing 354 amino acids, migrated on an sds-polyacrylamide gel with an apparent molecular weight of 40,000, in good agreement with the predicted molecular weigh ...19958588735
[isolation and reassociation of acetogen and methanogen in a syntrophobic coculture degrading butyrate anaerobically].anaerobic coculture bf2 which degraded butyrate into acetate and produced methane was isolated from granular methanogenic sludge. the coculture is associated syntrophically the syntrophomonas subsp. saponavida strain cf2 with methanobacterium formicicum strain mf2 and appeared to degraded c4 approximately c18 fatty acids including isobutyrate. the optimal temperature and ph for growth was 37 degrees c and 7.7 respectively. the strain cf2 was obtained in pure culture with crotonate as substrate a ...19958745550
role of formate and hydrogen in the degradation of propionate and butyrate by defined suspended cocultures of acetogenic and methanogenic bacteria.the butyrate-degrading syntrophospora bryantii degrades butyrate and a propionate-degrading strain (mpob) degrades propionate in coculture with the hydrogen- and formate-utilizing methanospirillum hungatii or methanobacterium formicicum. however, the substrates are not degraded in constructed cocultures with two methanobrevibacter arboriphilus strains which are only able to consume hydrogen. pure cultures of the acetogenic bacteria form both hydrogen and formate during butyrate oxidation with pe ...19958821782
formation of fatty acid-degrading, anaerobic granules by defined species.an endospore-forming, butyrate-degrading bacterium (strain bh) was grown on butyrate in monoxenic coculture with a methanogen. the culture formed dense aggregates when methanobacterium formicicum was the methanogenic partner, but the culture was turbid when methanospirillum hungatei was the partner. in contrast, a propionate-degrading, lemon-shaped bacterium (strain pt) did not form aggregates with methanobacterium formicicum unless an acetate-degrading methanosaeta sp. was also included in the ...199616535336
phylogenetic analyses of some extremely halophilic archaea isolated from dead sea water, determined on the basis of their 16s rrna sequences.twenty-two extremely halophilic aerobic archaeal strains were isolated from enrichments prepared from dead sea water samples collected 57 years ago. the isolates were phenotypically clustered into five different groups, and a representative from each group was chosen for further study. almost the entire sequences of the 16s rrna genes of these representatives, and of haloarcula hispanica atcc 33960, were determined to establish their phylogenetic positions. the sequences of these strains were co ...19968837434
the response of selected members of the archaea to the gram stain.archaea possess a broader range of cell envelope structural formats than eubacteria and their cell walls do not contain peptidoglycan. some archaea have only a single s-layer as their cell wall (e.g. methanococcus jannaschii and sulfolobus acidocaldarius), whereas others have multiple layers (e.g. methanospirillum hungatei). sometimes there can also be a high proportion of tetraether lipids in membranes to make the envelope more resilient to environmental stress (e.g. methanococcus jannaschii an ...19968885405
perturbation of syntrophic isobutyrate and butyrate degradation with formate and hydrogen.the effect of formate and hydrogen on isomerization and syntrophic degradation of butyrate and isobutyrate was investigated using a defined methanogenic culture, consisting of syntrophic isobutyrate-butyrate degrader strain ib, methanobacterium formicicum strain t1n, and methanosarcina mazeii strain t18. formate and hydrogen were used to perturb syntrophic butyrate and isobutyrate degradation by the culture. the reversible isomerization between isobutyrate and butyrate was inhibited by the addit ...199618629910
granular sludge formation in upflow anaerobic sludge blanket (uasb) reactors.the state of the art for upflow anaerobic sludge blanket (uasb) reactors is discussed, focusing on the microbiology of immobilized anaerobic bacteria and the mechanism of granule formation. the development of granular sludge is the key factor for successful operation of the uasb reactors. criteria for determining if granular sludge has developed in a uasb reactor is given based on the densities and diameters of the granular sludge. the shape and composition of granular sludge can vary significan ...199618623574
molecular microbial diversity of an anaerobic digestor as determined by small-subunit rdna sequence analysis.the bacterial community structure of a fluidized-bed reactor fed by vinasses (wine distillation waste) was analyzed. after pcr amplification, four small-subunit (ssu) rdna clone libraries of bacteria, archaea, procarya, and eucarya populations were established. the community structure was determined by operational taxonomic unit (otu) phylogenetic analyses of 579 partial rdna sequences (about 500 bp long). a total of 146 otus were found, comprising 133, 6, and 7 from the bacteria, archaea, and e ...19979212428
composition and role of extracellular polymers in methanogenic granules.methanobacterium formicicum and methanosarcina mazeii are two prevalent species isolated from an anaerobic granular consortium grown on a fatty acid mixture. the extracellular polysaccharides (eps) were extracted from methanobacterium formicicum and methanosarcina mazeii and from the methanogenic granules to examine their role in granular development. the eps made up approximately 20 to 14% of the extracellular polymer extracted from the granules, methanobacterium formicicum, and methanosarcina ...199716535504
diversity and structure of the methanogenic community in anoxic rice paddy soil microcosms as examined by cultivation and direct 16s rrna gene sequence retrieval.a dual approach consisting of cultivation and molecular retrieval of partial archaeal 16s rrna genes was carried out to characterize the diversity and structure of the methanogenic community inhabiting the anoxic bulk soil of flooded rice microcosms. the molecular approach identified four groups of known methanogens. three environmental sequences clustered with methanobacterium bryantii and methanobacterium formicicum, six were closely related but not identical to those of strains of methanosaet ...19989501436
thermodynamic stability of archaeal histones.the temperature, salt, and ph dependencies of unfolding of four recombinant (r) archaeal histones (rhfob from the mesophile methanobacterium formicicum, and rhmfa, rhmfb, and rhpya1 from the hyperthermophiles methanothermus fervidus and pyrococcus strain gb-3a) have been determined by circular dichroism spectroscopy (cd) and differential scanning calorimetry (dsc). the thermal unfolding of these proteins is > 90% reversible, with concentration-dependent apparent tm values and asymmetric unfoldin ...19989692945
nmr structure and comparison of the archaeal histone hfob from the mesophile methanobacterium formicicum with hmfb from the hyperthermophile methanothermus fervidus.the solution-state structure of the recombinant archaeal histone rhfob, from the mesophile methanobacterium formicicum, has been determined by two- and three-dimensional (3d) proton homonuclear correlated nuclear magnetic resonance (nmr) methods. on the basis of 951 nuclear overhauser effect (noe)-derived distance restraints, rhfob monomers form the histone fold and assemble into symmetric (rhfob)2 dimers that have a structure consistent with assembly into archaeal nucleosomes. rhfob exhibits ap ...19989692946
interspecific, intraspecific and interoperonic variability in the 16s rrna gene of methanogens revealed by length and single-strand conformation polymorphism analysis.thirty-seven strains of mesophilic and thermophilic methanogenic archaea, belonging to 30 species, were analyzed by length polymorphism (lp) and single-strand conformation polymorphism (sscp) of an amplified 300-bp fragment of the 16s rrna gene (escherichia coli positions 9-331) including the variable regions v1 and v2, lps and sscps were detected between species and between strains of the same species (methanobacterium formicicum). lps were found in mb. formicicum dsmz 3637, mb. ivanovii dsmz 2 ...19989682489
aminobacterium colombiensegen. nov. sp. nov., an amino acid-degrading anaerobe isolated from anaerobic sludge.a new gram-negative, non-sporulating, mesophilic, amino acid fermenting bacterium, designated strain ala-1(t) (t = type strain), was isolated from an anaerobic lagoon of a dairy wastewater treatment plant. the strain is curved (3-4 microm x 0.2-0.3 microm) and occurs singly or in pairs. optimum growth occurs at 37 degrees c and ph 7.3. the g+c content of the dna is 46 mol %. the strain requires yeast extract for growth, grows poorly on casamino acids, peptones, cysteine, and alpha-ketoglutarate, ...199816887649
[use of the level of g+c n dna for studying the molecular phylogeny o f methanogenic archaebacteria].a new method for theoretical analysis of the molecular phylogeny of bacteria, successfully applied earlier to nitrifying bacteria, was used to study the molecular phylogeny of methanogenic archaebacteria. the group studied included methanococcus igneus, methanococcus vannielii, methanothermus fervidus, methanolobus tindarius, methanobacterium formicicum, methanosarcina barkeri, methanobacterium thermoformicicum, methanoplanus limicola, methanospirillum hungatei, and methanobacterium thermoautotr ...199910624685
aminomonas paucivorans gen. nov., sp. nov., a mesophilic, anaerobic, amino-acid-utilizing bacterium.a novel, asaccharolytic, amino-acid-degrading bacterium, designated strain glu-3t, was isolated from an anaerobic lagoon of a dairy wastewater treatment plant. strain glu-3t stained gram-negative and was an obligately anaerobic, non-spore-forming, slightly curved, rod-shaped bacterium (0.3 x 4.0-6.0 microns) which existed singly or in pairs. the dna g+c content was 43 mol%. optimum growth occurred at 35 degrees c and ph 7.5 on arginine with a generation time of 16 h. good growth was obtained on ...199910425753
how stable is stable? function versus community composition.the microbial community dynamics of a functionally stable, well-mixed, methanogenic reactor fed with glucose were analyzed over a 605-day period. the reactor maintained constant ph and chemical oxygen demand removal during this period. thirty-six rrn clones from each of seven sampling events were analyzed by amplified ribosomal dna restriction analysis (ardra) for the bacteria and archaea domains and by sequence analysis of dominant members of the community. operational taxonomic units (otus), d ...199910427068
application of a tetrazolium dye as an indicator of viability in anaerobic bacteria.the use of the redox dye 5-cyano-2,3,-ditolyl tetrazolium chloride (ctc) for evaluating the metabolic activity of aerobic bacteria has gained wide application in recent years. in this study, we examined the utility of ctc in capturing the metabolic activity of anaerobic bacteria. in addition, the factors contributing to abiotic reduction of ctc were also examined. ctc was used in conjunction with the fluorochrome 5-(4,6-dichlorotriazinyl) aminofluorescein (dtaf), that targets bacterial cell wall ...199910480267
aminobacterium mobile sp. nov., a new anaerobic amino-acid-degrading bacterium.a novel, curved (0.3 x 4.0-5.0 microm), gram-negative, non-sporulating, mesophilic bacterium, designated strain ile-3t (t = type strain), was isolated from an anaerobic lagoon in a dairy wastewater treatment plant. optimal growth occurred at 37 degrees c and ph 7.4 on a medium containing serine as an energy source and yeast extract. the strain was motile by means of one or two lateral flagella. it required yeast extract for growth on serine, glycine, threonine and pyruvate. poor growth was obtai ...200010826812
production of volatile derivatives of metal(loid)s by microflora involved in anaerobic digestion of sewage sludge.gases released from anaerobic wastewater treatment facilities contain considerable amounts of volatile methyl and hydride derivatives of metals and metalloids, such as arsine (ash(3)), monomethylarsine, dimethylarsine, trimethylarsine, trimethylbismuth (tmbi), elemental mercury (hg(0)), trimethylstibine, dimethyltellurium, and tetramethyltin. most of these compounds could be shown to be produced by pure cultures of microorganisms which are representatives of the anaerobic sewage sludge microflor ...200010877769
isolation and identification of ruminal methanogens from grazing cattle.to obtain information on the diversity of ruminal methanogens in grazing animals, three ruminal methanogens from grazing cattle were characterized and identified. two of the isolates were rod-shaped, with one staining gram-positive and being non-motile (brm9), and the other (brm16) staining gram-negative and being motile. these isolates grew only on h(2)/co(2) and formate, and optimally at 38 degrees c and ph 6.5-7.0. the third isolate (cm1) was non-motile, pseudosarcina-shaped, and grew on h(2) ...200010706664
mutational analysis of differences in thermostability between histones from mesophilic and hyperthermophilic archaea.amino acid residues responsible for the large difference in thermostability between hmfb and hfob, archaeal histones from the hyperthermophile methanothermus fervidus and the mesophile methanobacterium formicicum, respectively, have been identified by site-specific mutagenesis. the thermal denaturation of approximately 70 archaeal histone variants has been monitored by circular dichroism, and the data generated were fit to a two-state unfolding model (dimer-->two random coil monomers) to obtain ...200010633118
single strand conformation polymorphism monitoring of 16s rdna archaea during start-up of an anaerobic digester.a laboratory-scale continuously mixed anaerobic digester was inoculated with a mix of anaerobic sludge and fed with glucose. the start-up strategy was progressive and chemical analyses were done to evaluate digester performance from day 1 to day 107. in parallel, archaeal community dynamics were monitored by sscp analysis of the v3 region of 16s rdna genes and further characterized by partial sequencing of 16s rdna genes. at day 1 the inoculum contained at least five distinct archaeal peaks clos ...200111137601
tetrachloroethene dehalorespiration and growth of desulfitobacterium frappieri tce1 in strict dependence on the activity of desulfovibrio fructosivorans.tetrachloroethene (pce) dehalorespiration was investigated in a continuous coculture of the sulfate-reducing bacterium desulfovibrio fructosivorans and the dehalorespiring desulfitobacterium frappieri tce1 at different sulfate concentrations and in the absence of sulfate. fructose (2.5 mm) was the single electron donor, which could be used only by the sulfate reducer. with 2.5 mm sulfate, the dehalogenating strain was outnumbered by the sulfate-reducing bacterium, sulfate reduction was the domin ...200211823202
[analysis of the anaerobic microbial community capable of degrading p-toluene sulphonate].three strains of clostridium sp., 14 (vkm b-2201), 42 (vkm b-2202), and 21 (vkm b-2279), two methanogens, methanobacterium formicicum mh (vkm b-2198) and methanosarcina mazei mm (vkm b-2199), and one sulfate-reducing bacterium, desulfovibrio sp. sr1 (vkm b-2200), were isolated in pure cultures from an anaerobic microbial community capable of degrading p-toluene sulfonate. strain 14 was able to degrade p-toluene sulfonate in the presence of yeast extract and bactotryptone and, like strain 42, to ...200314768540
degradation of cinnamate via beta-oxidation to benzoate by a defined, syntrophic consortium of anaerobic bacteria.a syntrophic consortium was enriched in a basal medium containing cinnamate as the carbon and energy source. it was found to consist of three morphologically distinct microbes, viz., a short, rod-shaped, non-motile bacterium with distinctly pointed ends, papillibacter cinnamivorans; a rod-shaped, motile bacterium with rounded ends, syntrophus sp.; and a methanoarchaeon, methanobacterium sp. this methanogen was then replaced by a collection strain of methanobacterium formicicum. a syntrophic inte ...200312432464
characteristics of an anaerobic, syntrophic, butyrate-degrading bacterium in paddy field soil.the number of syntrophic butyrate-degrading bacteria in a flooded paddy field soil was 1.7 x 10(3) mpn/g dry soil. butyrate was degraded to acetate and methane when paddy soils were incubated anaerobically with the addition of butyrate. however, butyrate degradation was completely suppressed by the addition of the specific inhibitor of methanogenesis, 2-bromoethanesulfonate (bes) to the soil. a hydrogen-using methanogen, strain tm-8, was isolated from flooded paddy field soil. strain tm-8 was id ...200314586091
purification and properties of the formate dehydrogenase and characterization of the fdha gene of sulfurospirillum multivorans.the soluble periplasmic subunit of the formate dehydrogenase fdha of the tetrachloroethene-reducing anaerobe sulfurospirillum multivorans was purified to apparent homogeneity and the gene ( fdha) was identified and sequenced. the purified enzyme catalyzed the oxidation of formate with oxidized methyl viologen as electron acceptor at a specific activity of 1683 nkat/mg protein. the apparent molecular mass of the native enzyme was determined by gel filtration to be about 100 kda, which was confirm ...200314610638
stability and folding mechanism of mesophilic, thermophilic and hyperthermophilic archael histones: the importance of folding intermediates.the equilibrium stabilities to guanidinium chloride (gdmcl)-induced denaturation and kinetic folding mechanisms have been characterized for three archael histones: hfob from the mesophile methanobacterium formicicum; hmfb from the thermophile methanothermus fervidus; and hpya1 from the hyperthermophile pyrococcus strain gb-3a. these histones are homodimers of 67 to 69 residues per monomer. the equilibrium unfolding transitions, as measured by far-uv circular dichroism (cd) are highly reversible, ...200415313621
performances and microbial features of a granular activated carbon packed-bed biofilm reactor capable of an efficient anaerobic digestion of olive mill wastewaters.anaerobic digestion of olive mill wastewaters is generally performed in anaerobic contact bioreactors where the removal of toxic phenols is often unsatisfactory. in the present work we show that a granular activated carbon packed-bed biofilm reactor can be successfully used to achieve effective and reproducible wastewater decontamination even at high organic loads. a comparison of 16s rrna gene sequences of the inoculum and of biomass samples from different districts of the reactor revealed enri ...200419712310
in vitro selection of an archaeal rnase p rna mimics natural variation.archaeal and bacterial rnase p rnas are similar in sequence and secondary structure, but in the absence of protein, the archaeal rnas are much less active and require extreme ionic conditions for activity. to assess how readily the activity of the archaeal rna alone could be improved by small changes in sequence, in vitro selection was used to generate variants of a methanobacterium formicicum rnase p rna: bacillus subtilus pre-trna(asp) self-cleaving conjugate rna. functional variants were gene ...200415810433
the first true obligately syntrophic propionate-oxidizing bacterium, pelotomaculum schinkii sp. nov., co-cultured with methanospirillum hungatei, and emended description of the genus pelotomaculum.a gram-positive, spore-forming, syntrophic propionate-oxidizing bacterium, pelotomaculum schinkii sp. nov. strain hh(t), was isolated as a co-culture with methanospirillum hungatei jf-1(t) from anaerobic, freeze-dried granular sludge obtained from an upflow anaerobic sludge bed reactor treating sugar beet wastewater. the bacterium converted propionate to acetate in co-culture with methanospirillum hungatei jf-1(t) or methanobacterium formicicum mf(nt), but not in co-culture with methanobrevibact ...200516014504
effect of wastewater composition on archaeal population diversity.distribution and occurrence of archaea and methanogenic activity in a laboratory scale, completely mixed anaerobic reactor treating pharmaceutical wastewaters were investigated and associated with reactor performance. the reactor was initially seeded with anaerobic digester sludge from an alcohol distillery wastewater treatment plant and was subjected to a three step feeding strategy. the feeding procedure involved gradual transition from a glucose containing feed to a solvent stripped pharmaceu ...200515878030
survival of methanogens during desiccation: implications for life on mars.the relatively recent discoveries that liquid water likely existed on the surface of past mars and that methane currently exists in the martian atmosphere have fueled the possibility of extant or extinct life on mars. one possible explanation for the existence of the methane would be the presence of methanogens in the subsurface. methanogens are microorganisms in the domain archaea that can metabolize molecular hydrogen as an energy source and carbon dioxide as a carbon source and produce methan ...200616916281
syntrophomonas cellicola sp. nov., a spore-forming syntrophic bacterium isolated from a distilled-spirit-fermenting cellar, and assignment of syntrophospora bryantii to syntrophomonas bryantii comb. nov.a spore-forming, anaerobic, syntrophic fatty-acid-oxidizing bacterium, strain 19j-3(t), was isolated from a distilled-spirit-fermenting cellar in hebei province, china. the cells were slightly curved rods with a spore at the end of the cell. the optimal temperature for growth was around 37 degrees c and growth occurred in the range 25-45 degrees c. the ph range for growth was 6.5-8.5 and the optimum ph was 7.0-7.5. crotonate was the only substrate that allowed the strain to grow in pure culture. ...200617012556
pcr-based dgge fingerprinting and identification of methanogens detected in three different types of uasb granules.methane is produced by various methanogenic bacteria present in upflow anaerobic sludge blanket (uasb) bioreactors. methane can be used to predict and improve uasb bioreactor efficiency. the methanogen population in the granules can be influenced by the composition of the substrate. the aim of this study was to fingerprint and identify the methanogens present in three different types of uasb granules that had been used to treat winery, brewery and peach-lye canning effluents. this was done using ...200616423659
syntrophomonas zehnderi sp. nov., an anaerobe that degrades long-chain fatty acids in co-culture with methanobacterium formicicum.an anaerobic, mesophilic, syntrophic fatty-acid-oxidizing bacterium, designated strain ol-4(t), was isolated as a co-culture with methanobacterium formicicum dsm 1535(nt) from an anaerobic expanded granular sludge bed reactor used to treat an oleate-based effluent. strain ol-4(t) degraded oleate, a mono-unsaturated fatty acid, and straight-chain fatty acids c(4 : 0)-c(18 : 0) in syntrophic association with methanobacterium formicicum dsm 1535(nt). even-numbered fatty acids were degraded to aceta ...200717329794
syntrophomonas wolfei subsp. methylbutyratica subsp. nov., and assignment of syntrophomonas wolfei subsp. saponavida to syntrophomonas saponavida sp. nov. comb. nov.a spore-forming bacterium strain 4j5(t) was isolated from rice field mud. when co-cultured with methanobacterium formicicum dsm 1535(t), strain 4j5(t) could syntrophically degrade saturated fatty acids with 4-8 carbon atoms, including 2-methylbutyrate. phylogenetic analysis based on 16s rrna gene similarity showed that strain 4j5(t) was most closely related to syntrophomonas wolfei subsp. wolfei dsm 2245(t) (98.9% sequence similarity); however, it differed from the latter in the substrates utili ...200717223300
thermophilic methanogenic archaea in compost material: occurrence, persistence and possible mechanisms for their distribution to other environments.since compost is widely used as soil amendment and the fact that during the processing of compost material high amounts of microorganisms are released into the air, we investigated whether compost may act as a carrier for thermophilic methanogens to temperate soils. all eight investigated compost materials showed a clear methane production potential between 0.01 and 0.98 micromol ch(4) g dw(-1)h(-1) at 50 degrees c. single strand conformation polymorphism (sscp) and cloning analysis indicated th ...200717988815
microbial diversity and methanogenic potential in a high temperature natural gas field in japan.microbial diversity and methanogenic potential in formation water samples from a dissolved-in-water type gas field were investigated by using 16s rrna gene libraries and culture-based methods. two formation water samples (of 46 and 53 degrees c in temperature) were obtained from a depth of 700 to 800 m. coenzyme f(420)-autofluorescence indicated that 10(3)-10(4) cells per ml of active methanogens were present, accounting for at least 10% of the total cell count. the 16s rrna gene sequence analys ...200717265161
relationships between anaerobic consortia and removal efficiencies in an uasb reactor degrading 2,4 dichlorophenol (dcp).to gain more insight into the interactions between anaerobic bacteria and reactor performances (chemical oxygen demand-cod, 2,4 dichlorophenol-2,4 dcp removals, volatile fatty acid-vfa, and methane gas productions) and how they depended on operational conditions the microbial variations in the anaerobic granular sludge from an upflow anaerobic sludge blanket (uasb) reactor treating 2,4 dcp was studied. the study was composed of two parts. in the first part, the numbers of methanogens and acedoge ...200817379394
filamentous granular sludge bulking in a laboratory scale uasb reactor.filamentous bulking was observed in a lab scale upflow anaerobic sludge blanket (uasb) reactor. granules failed to settle normally and disintegrated. the characteristics of the granules in structure and microbial composition during the granulation process were investigated by means of scanning electron microscopy (sem) and denaturing gradient gel electrophoresis (dgge) technique. granules with high porosity instead of compact ones were developed in the reactor and methanosaeta concilii and metha ...200817884465
evaluation of methanogenic strains and their ability to endure aeration and water stress.during periods of drainage, both water stress and oxygen can cause damage to indigenous methanogens. in the present study, we evaluated the tolerance of seven methanogenic strains (methanobrevibacter arboriphilicus, methanobacterium formicicum, methanococcus vannielii, methanospirillum hungatei, methanoculleus olentangyi, methanoplanus limicola, and methanosarcina mazei) to long-term exposure to air/nitrogen and drying. we found that these methanogenic strains except for m. limicola and m. olent ...200817990030
methanobacterium kanagiense sp. nov., a hydrogenotrophic methanogen, isolated from rice-field soil.a pure culture of an obligately anaerobic, hydrogenotrophic, methanogenic archaeon, designated strain 169(t), which grows with hydrogen and carbon dioxide as the sole energy and carbon sources, was isolated from an anaerobic propionate-oxidizing enrichment culture originally obtained as an inoculant from rice-field soil in japan. cells of strain 169(t) were non-motile, gram-reaction-variable and rod-shaped or slightly curved rods with rounded ends (1.6-5.0×0.35-0.5 µm). strain 169(t) had fimbria ...201020639228
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