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syntrophic association of a butyrate-degrading bacterium and methanosarcina enriched from bovine rumen fluid.an anaerobic butyrate-degrading bacterium, morphologically similar to syntrophomonas wolfei, was isolated in coculture with desulfovibrio strain g11 from an enrichment of bovine rumen fluid. a methanosarcina species was the major h2-using organism in the enrichment. the results are discussed in relationship to the absence of methanospirillum hungatei, the h2-using methanogen usually found in association with s. wolfei, and the finding of methanosarcina rather than methanobrevibacter ruminantium ...19817224635
nickel requirement and factor f430 content of methanogenic bacteria.methanobacterium thermoautotrophicum has been reported to require nickel for growth and to contain high concentrations of a nickel tetrapyrrole designated factor f430. in this communication it is shown that all methanogenic bacteria investigated incorporated nickel during growth and also synthesized factor f430. this was also true for methanobrevibacter smithii, which is dependent on acetate as a carbon source, and for methanosarcina barkeri growing on acetate or methanol as energy sources. othe ...19817298577
anaerobic degradation of lactate by syntrophic associations of methanosarcina barkeri and desulfovibrio species and effect of h(2) on acetate degradation.when grown in the absence of added sulfate, cocultures of desulfovibrio desulfuricans or desulfovibrio vulgaris with methanobrevibacter smithii (methanobacterium ruminantium), which uses h(2) and co(2) for methanogenesis, degraded lactate, with the production of acetate and ch(4). when d. desulfuricans or d. vulgaris was grown in the absence of added sulfate in coculture with methanosarcina barkeri (type strain), which uses both h(2)-co(2) and acetate for methanogenesis, lactate was stoichiometr ...198116345708
fermentation of cellulose to methane and carbon dioxide by a rumen anaerobic fungus in a triculture with methanobrevibacter sp. strain ra1 and methanosarcina barkeri.the fermentation of cellulose by a rumen anaerobic fungus in the presence of methanobrevibacter sp. strain ra1 and methanosarcina barkeri strain 227 resulted in the formation of 2 mol each of methane and carbon dioxide per mol of hexose fermented. coculture of the fungus with either methanobrevibacter sp. or m. barkeri produced 0.6 and 1.3 mol of methane per mol of hexose, respectively. acetate, formate, ethanol, hydrogen, and lactate, which are major end products of cellulose fermentation by th ...198216346048
antigenic analysis of methanomicrobiales and methanobrevibacter arboriphilus.preparation of new antisera has permitted more comprehensive immunological analyses of the two families of methanomicrobiales. methanomicrobiaceae and methanosarcinaceae, and the species methanobrevibacter arboriphilus. immunological analysis was carried out with antibody probes against 23 strains, including almost all genera and species of methanogens. the absence of cross-reactions between families of methanogens was confirmed. methanomicrobium and methanogenium were found to be immunologicall ...19826752119
isolation of methanobrevibacter smithii from human feces.fecal specimens from nine adults were examined for the presence of methanogenic bacteria. enrichment cultures of five specimens produced methane in 5 days. of these five specimens, three were tested and produced methane during a short-term incubation. four specimens did not produce methane in either short-term incubation or in enrichment culture. each methanogenic culture contained methanogens similar in morphology to organisms of the genus methanobrevibacter and showed factor-420 fluorescence b ...19826798932
enumeration of methanobrevibacter smithii in human feces.a plating medium containing cephalothin and clindamycin was developed for enumeration and isolation of methanogens in human feces. specimens from nine ch4-producing subjects had total anaerobe counts of 1-8 x 1011/g dry weight. methanogen counts on the antibiotic medium ranged from 0.001 - 12.6% of the total anaerobe count. there was no correlation between age, sex or percent dry fecal weight and the ratio of methanogens to total counts. specimens from eight non-ch4-producing individuals contain ...19827065811
stability of methanobrevibacter smithii populations in the microbial flora excreted from the human large bowel.total anaerobic bacteria and methanobrevibacter smithii populations were enumerated in fecal specimens from two individuals over 10- and 13-month periods. the ratio of m. smithii to total anaerobic count varied between the individuals, but it was a relatively constant proportion of the large-bowel microbial flora within each individual. neither a barium enema examination of one subject nor a radical change in the diet of the other had any long-term effect on the methanogen populations.19836824322
rapidly growing rumen methanogenic organism that synthesizes coenzyme m and has a high affinity for formate.methanogenic bacteria with a coccobacillus morphology similar to methanobrevibacter ruminantium were isolated from the bovine rumen. one isolate, 10-16b, represented a previously undescribed rumen population that, unlike m. ruminantium, synthesized coenzyme m, grew rapidly (mu = 0.24 h-1) on h2-co2 in a complex medium, had simple nutritional requirements, and metabolized formate at reported rumen concentrations. h2 was metabolized to partial pressures 10-fold lower than those reported for the ru ...19846433795
methanogens and anaerobes in a colon segment isolated from the normal fecal stream.methanogens were in the isolated sigmoid colon but not in the colostomy bag of a woman with a left hemicolectomy with end colostomy and mucous fistula. the predominant methanogen was methanobrevibacter smithii. an anaerobic bacterial community supported by nondietary substrates was present in the isolated sigmoid colon.19846486788
evidence for a nickel-containing carbon monoxide dehydrogenase in methanobrevibacter arboriphilicus.in growing cultures of methanobrevibacter arboriphilicus (methanobrevibacter arboriphilus), the synthesis of active carbon monoxide dehydrogenase required nickel. the 21-fold-purified enzyme from 63ni-labeled cells of m. arboriphilicus comigrated with 63ni during gel filtration. these results provide evidence that the carbon monoxide dehydrogenase of methanogens is a nickel protein.19846546569
is coenzyme m bound to factor f430 in methanogenic bacteria? experiments with methanobrevibacter ruminantium.coenzyme m (2-mercaptoethane sulfonic acid) and factor f430 (a nickel porphinoid) are coenzymes found in methanogenic bacteria. recently it has been proposed that in these bacteria a coenzyme mf430 also exists which plays a key role in methane formation and in which coenzyme m and f430 are bound to each other. to test this hypothesis methanobrevibacter ruminantium, which requires coenzyme m as a vitamin, was grown in the presence of [2-14c]comsh. f430 and 'com' (mixture of comsh and its disulfid ...19853920049
sequence divergence of an archaebacterial gene cloned from a mesophilic and a thermophilic methanogen.a 1.6-kb fragment of dna from the thermophilic, methane-producing, anaerobic archaebacterium methanobacterium thermoautotrophicum delta h has been cloned and sequenced. this dna complements mutations in both the pure1 and pure2 loci of escherichia coli. the sequence of the m. thermoautotrophicum dna predicts that complementation in e. coli results from the synthesis of a polypeptide with a molecular weight of 36,249. a polypeptide apparently of this molecular weight is synthesized in e. coli min ...19853936936
structure of genes and an insertion element in the methane producing archaebacterium methanobrevibacter smithii.dna fragments cloned from the methanogenic archaebacterium methanobrevibacter smithii which complement mutations in the pure and proc genes of e. coli have been sequenced. sequence analyses, transposon mutagenesis and expression in e. coli minicells indicate that pure and proc complementations result from the synthesis of m. smithii polypeptides with molecular weights of 36,697 and 27,836 respectively. the encoding genes appear to be located in operons. the m. smithii genome contains 69% a/t bas ...19852993814
gelrite as an agar substitute for the cultivation of mesophilic methanobacterium and methanobrevibacter species.gelrite was evaluated as a gelling agent for the growth of mesophilic methanobacterium and methanobrevibacter species. gelrite was shown to be superior to agar in its gel strength and clarity. viable cell counts and colony sizes of methanobacterium species were greater on gelrite-based medium compared with agar-based medium.198516346906
characteristics of methanogens isolated from bovine rumen.six strains of methanogens were isolated from 10(-8) and 10(-9) ml of bovine rumen contents. all strains had the morphologic and physiologic characteristics of methanobrevibacter spp. four strains required coenzyme m; two did not. growth of all strains either depended on or was stimulated by a mixture of isobutyric, isovaleric, 2-methylbutyric, and valeric acids. none of the strains reacted with antiserum against the type strain of methanobrevibacter ruminantium.19863954338
isolation of an antigenically unique methanogen from human feces.a methanogenic bacterium with the morphological and physiological properties of the genus methanobrevibacter was isolated from the feces of a japanese man who excreted methane in his breath. indirect immunofluorescence staining revealed that the isolate had an antigenicity unrelated to that of any known members of the genus methanobrevibacter.19863513706
incidence of methanogenic bacteria in a sigmoidoscopy population: an association of methanogenic bacteria and diverticulosis.this study determined the incidence and concentration of methane-producing bacteria in tap water enema samples of 130 individuals taken before sigmoidoscopy. the number of subjects classified in five major colonic groups were as follows: normal colon 36, diverticulosis 57, inflammatory bowel disease 11, colon polyps 34, and colon cancer 11. some patients were placed in more than one category. ninety four of the subjects or 72% had methanogenic bacteria ranging in concentration from 6 to about 3 ...19863721294
31p-nmr spectra of methanogens: 2,3-cyclopyrophosphoglycerate is detectable only in methanobacteria strains.the unique compound 2,3-cyclopyrophosphoglycerate occurs at a detectable concentration in the genera methanobacterium and methanobrevibacter but not in methanococcus, methanospirillum and methanosarcina, as shown by a 31p-nmr survey of several different methanogens. metabolic poisons (carbonyl cyanide m-chlorophenylhydrazone and valinomycin) do not decrease the level of the cyclic pyrophosphate in methanobacterium thermoautotrophicum; therefore, it cannot be a phosphagen, i.e., an energy storage ...19863754772
a diphytanyl ether analog of phosphatidylserine from a methanogenic bacterium, methanobrevibacter arboriphilus.several ninhydrin-positive lipids were found in methanogenic bacteria and the structure of one of them, designated as pnl2 from methanobrevibacter arboriphilus, was identified as a diphytanyl ether analog of phosphatidylserine. the chromatographic behavior of the lipid on thin-layer plates and on a deae-cellulose column was identical to the ester form of phosphatidylserine. the infrared spectra showed the presence of amino, carboxyl, ether, and phosphate groups, and the absence of an ester linka ...19863760709
13c nmr spectroscopy of methanobacterium thermoautotrophicum. carbon fluxes and primary metabolic pathways.the flux of 13c-labeled carbons from the soluble metabolite 2,3-cyclopyrophosphoglycerate (cpp), a novel compound found in high concentrations exclusively in methanobacteria and methanobrevibacter, into carbohydrate-containing material has been deduced by solid-state 13c nmr spectroscopy which strongly argues for a role in gluconeogenesis for this unique metabolite. the turnover rates, but not the steady-state levels, of cpp labeled by 13co2 or [13c]acetate depend dramatically on cell growth con ...19863782122
cloning and characterization of a 12-gene cluster from bacillus subtilis encoding nine enzymes for de novo purine nucleotide synthesis.an approximately 16-kilobase pair region of the bacillus subtilis chromosome at 55 degrees containing genes for de novo purine nucleotide synthesis (piggot, p. j., and hoch, j. a. (1985) microbiol. rev. 49, 158-179) was cloned. the nucleotide sequence of over 13 kilobase pairs indicates that this region contains a cluster of 12 genes, 11 of which encode enzymes that catalyze the 10 reactions for de novo purine nucleotide synthesis from 5-phosphoribosyl 1-pyrophosphate to imp. the genes were iden ...19873036807
quin's oval and other microbiota in the rumens of molasses-fed sheep.two rumen-cannulated wether sheep were fed a diet containing 1 kg of a liquid-molasses mixture, 80 g of soybean oil meal, and 100 g of chopped wheat straw once a day. in 6 weeks and thereafter, the microbiota adapted such that quin's oval, a very large bacterium, was present in huge numbers (11.3 x 10(10) and 1.3 x 10(10) ml-1 after 73 days). direct microscopic counts were also done on small bacteria, moderate-sized selenomonas spp., and small entodinium spp., which were the only protozoa seen. ...19873300549
energetic analysis of the growth of methanobrevibacter arboriphilus a2 in hydrogen-limited continuous cultures.hydrogen-limited chemostat cultures of methanobrevibacter arboriphilus a2 were carried out. the available electron balance and carbon balance in m. arboriphilus a2 and other methanogenic strains grown on various substrates were well satisfied. this indicates that no extracellular organic products were formed during methanogenic growth. the molar growth yields for methane (y(x/ch(4) )) were calculated as 1.06-1.42 g cell/mol ch(4) at dilution rate (0.21-0.43 day(-1)). the smaller y(x/ch(4) ) of m ...198718576419
methanogenic bacteria from human dental plaque.samples of human dental plaque were examined for the presence of methanogenic bacteria. of 54 samples from 36 patients, 20 yielded h2/co2-using methanogenic enrichment cultures. all methanogen-positive samples were from patients with some degree of periodontal disease. the predominant populations in the enrichments had morphologies characteristic of methanobrevibacter spp. in six enrichments derived from three patients, the common methanogen was antigenically similar to methanobrevibacter smithi ...19883355146
a simple chromatographic procedure for the detection of cyclized archaebacterial glycerol-bisdiphytanyl-glycerol tetraether core lipids.archaebacterial glycerol-bisdiphytanyl-glycerol tetraether core lipids containing from one to eight cyclopentane rings could be resolved from each other and from the parent uncyclized c40, c40 lipid by tlc. the core lipids of examples from the genera methanobacterium, methanobrevibacter, methanogenium and methanoplanus did not contain cyclized forms of glycerol-bisdiphytanyl-glycerol tetraethers, whereas the core lipids of methanosarcina barkeri contained glycerol-bisdiphytanyl-glycerol tetraeth ...19883151990
structural diversity among methanofurans from different methanogenic bacteria.an examination of the methanofurans isolated from a wide range of methanogenic bacteria and from archaeoglobus fulgidus has revealed at least five chromatographically distinct methanofurans. bacteria from each major genus of methanogenic bacteria have been found to contain a chemically different methanofuran. the nature of the differences in the methanofurans appears to lie in the modification of the side chain attached to the basic core structure of 4-[n-(gamma-l-glutamyl-gamma-l-glutamyl)-p-(b ...19883170480
[clindamycin-resistant mutants of a methanobrevibacter species]. 19883250091
7-methylpterin derivatives in extracts of methanogens characterized by a relatively low methanopterin content.cofactor extracts of five hydrogenotrophic methanogenic bacteria which contain relatively low amounts of methanopterin were screened for the presence of 7-methylpterin derivatives. extracts of methanospirillum hungatei, methanobrevibacter smithii and methanoplanus endosymbiosus were found to contain 7-methylpterin and methanopterin. these compounds were absent in extracts of methanogenium thermophilicum and methanogenium tatii. an unidentified methanopterin-like compound was detected in extracts ...19883255348
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
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
increase in colonic methanogens and total anaerobes in aging rats.methanogens are present in the colons of our local wistar rat colony. we studied the changes in concentrations of their fecal methanogenic and nonmethanogenic bacteria with age as a model of the development of these communities in humans. we found that the predominant methanogen in the rats is a methanobrevibacter species. the log of the concentration of total anaerobes increased from 9.8/g (dry weight) at 3.0 weeks of age (shortly after weaning) to 10.7/g (dry weight) at 96 weeks (shortly befor ...19892604389
enhanced resistance of anaerobic rumen fungi to the ionophores monensin and lasalocid in the presence of methanogenic bacteria.the presence of methanobrevibacter smithii altered the susceptibility of the anaerobic fungi neocallimastix frontalis and piromonas communis to the carboxylic ionophores monensin and lasalocid. the ionophores depressed growth (measured by chitin accretion), the uptake of glucose and the production of h2, formate and acetate by the fungi growing axenically in semi-solid medium. in the presence of m. smithii, the sensitivity of the fungi to monensin and lasalocid was decreased. for example, the up ...19892722716
influence of hydrogen-consuming bacteria on cellulose degradation by anaerobic fungi.the presence of methanogens methanobacterium arboriphilus, methanobacterium bryantii, or methanobrevibacter smithii increased the level of cellulose fermentation by 5 to 10% in cultures of several genera of anaerobic fungi. when neocallimastix sp. strain l2 was grown in coculture with methanogens the rate of cellulose fermentation also increased relative to that for pure cultures of the fungus. methanogens caused a shift in the fermentation products to more acetate and less lactate, succinate, a ...19902082826
methanogenic bacteria in human vaginal samples.twelve vaginal samples were collected from separate patients, processed anaerobically, and added to methanogenic enrichment medium. methanogenic activity was detected in two samples, both of which were from patients with bacterial vaginosis. none of the samples from healthy patients yielded positive methanogen cultures. one sample from a patient with bacterial vaginosis did not show any detectable methanogenic activity. two methanogen isolates were obtained from one of the methanogen-positive sa ...19902199527
effect of coumarin on glucose uptake by anaerobic rumen fungi in the presence and absence of methanobrevibacter smithii.the effect of coumarin (1,2 benzopyrone) on glucose utilisation by the anaerobic rumen fungi neocallimastix frontalis and n. patriciarum has been compared with the effect of p-coumaric acid. both compounds largely inhibited glucose utilisation by n. patriciarum strain cx when present in the medium at a concentration of 2.5 mm, and had a similar effect on n. frontalis strain re1 at 5 mm. although in earlier studies co-culturing rumen fungi with methanobrevibacter smithii enhanced resistance to io ...19902227350
[demonstration of the presence of methanobrevibacter in a colon cancer chinese patient].a fecal specimen from a chinese patient (85-year-old man) suffering from colonic cancer was examined for the presence of methane-producing bacteria. as a result, a methanobrevibacter organism was isolated. our isolate did not grow in the presence of bile salts, a result different from methanobrevibacter from healthy americans' feces by miller et al.19902251834
effect of methanobrevibacter smithii on xylanolytic activity of anaerobic ruminal fungi.three different ruminal anaerobic fungi, neocallimastix frontalis pnk2, sphaeromonas communis b7, and piromonas communis b19, were grown axenically or in coculture with methanobrevibacter smithii on xylan. n. frontalis and s. communis in monoculture and coculture accumulated xylobiose, xylose, and arabinose in the growth medium; arabinose was not metabolized, but xylobiose and xylose were subsequently used. the transient accumulation of xylose was much less evident in cocultures. both the rate a ...199016348244
quantitative microbiological analysis of bacterial community shifts in a high-rate anaerobic bioreactor treating sulfite evaporator condensate.the bacterial population of a high-rate, anaerobic, fixed-bed loop reactor treating sulfite evaporator condensate from the pulp industry was studied over a 14-month period. this period was divided into seven cycles that included a startup at the beginning of each cycle. some 82% of the total biomass was immobilized on and between the porous glass rings filling the reactor. the range of the total number of microorganisms in these biofilms was 2 x 10 to 7 x 10 cells per ml. enumeration and charact ...199016348253
diversity and population dynamics of methanogenic bacteria in a granular consortium.upflow anaerobic sludge blanket bioreactor granules were used as an experimental model microbial consortium to study the dynamics and distribution of methanogens. immunologic methods revealed a considerable diversity of methanogens that was greater in mesophilic granules than in the same granules 4 months after a temperature shift from 38 to 55 degrees c. during this period, the sizes of the methanogenic subpopulations changed with distinctive profiles after the initial reduction caused by the s ...199116348508
[methanogens from feces of patients with intestine disorder].fecal specimens from 10 colorectal cancer, 1 duodenum diverticulosis and 2 healthy adults were examined. nine fecal enrichments contained methanobrevibacter. the percentage of methanogen positive individuals was 69% methanobrevibacter were isolated from fecal enrichments of 4 colorectal cancer and 1 duodenum diverticulosis. the percentage of breath methane positive individuals and methane production had significantly increased in colorectal cancer patients. it will be hopeful that methane produc ...19911814049
[oral bacterial flora and its pathogenic potential].the oral flora is a complex body formed by at least a hundred bacterial species which can be more or less regular residents in the oral cavity. thanks to a developing taxonomy related to progress made in bacterial identification, these oral species can be separated into five groups based gram staining and morphology: the gram positive cocci group (streptococcus, staphylococcus and related geni), the gram negative cocci group (neisseria, veillonella and related geni), the gram positive bacilli gr ...19911864855
effect of propionate toxicity on methanogen-enriched sludge, methanobrevibacter smithii, and methanospirillum hungatii at different ph values.the effect of propionate toxicity at different ph values (6.5, 7.0, and 8.0) on methanogen-enriched sludge. methanobrevibacter smithii, and methanospirillum hungatii was studied. organisms were grown in balch medium 3 in hungate tubes, and toxicity was characterized by a decrease in production of methane and in bacterial numbers. propionate inhibited bacterial growth and cumulative methane production at concentrations as low as 20 mm. in the absence of propionate, the methanogen-enriched sludge ...19911872605
bacteriological composition and structure of granular sludge adapted to different substrates.the bacteriological composition and ultrastructure of mesophilic granular methanogenic sludge from a large-scale upflow anaerobic sludge blanket reactor treating wastewater from a sugar plant and of sludge granules adapted to ethanol and propionate were studied by counting different bacterial groups and by immunocytochemical methods. propionate-grown granular sludge consisted of two types of clusters, those of a rod-shaped bacterium immunologically related to methanothrix soehngenii and those co ...19911892385
methanogenic bacteria as endosymbionts of the ciliate nyctotherus ovalis in the cockroach hindgut.production of methane in the hindgut of the cockroach periplaneta americana was found to vary, depending on the feeding regimen. methane production was positively correlated with the numbers of the ciliate nyctotherus ovalis living in the cockroach hindgut. defaunation of the cockroaches by means of low concentrations of metronidazole (flagyl) resulted in a quick drop of methane production. addition of the methanogenic substrates acetate and formate to isolated hindguts stimulated methane produc ...19911908205
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
influence of metronidazole, co, co(2), and methanogens on the fermentative metabolism of the anaerobic fungus neocallimastix sp. strain l2.the effects of metronidazole, co, methanogens, and co(2) on the fermentation of glucose by the anaerobic fungus neocallimastix sp. strain l2 were investigated. both metronidazole and co caused a shift in the fermentation products from predominantly h(2), acetate, and formate to lactate as the major product and caused a lower glucose consumption rate and cell protein yield. an increased lactate dehydrogenase activity and a decreased hydrogenase activity were observed in cells grown under both cul ...199316349022
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
cofactor contents of methanogenic bacteria reviewed.the content of specific methanogenic cofactors was assessed for a range of hydrogenotrophic and methylotrophic methanogenic bacteria grown on different substrates using high performance liquid chromatography. in general, all methanogens were found to contain coenzyme f420 analogues, methanopterin (mpt) analogues and 5-hydroxybenzimidazolylcobamide (vitamin b12-hbi). in hydrogenotrophic methanogens of the genera methano-bacterium and methanobrevibacter, as a rule, coenzymes f420-2 and f420-3 as w ...19947916957
the effects of co-cultivation with the acetogen acetitomaculum ruminis on the fermentative metabolism of the rumen fungi neocallimastix patriciarum and neocallimastix sp. strain l2.the effects of co-cultivation with the hydrogen-utilizing acetogenic bacterium acetitomaculum ruminis on the fermentative activities of the rumen fungi neocallimastix patriciarum or neocallimastix sp. l2 were investigated. in both co-cultures acetate production increased, making it the predominant fermentation product, as the accumulation of lactate, formate, ethanol, h2 and (in the case of neocallimastix sp. l2) succinate all decreased. the effects of co-cultivation with methanobrevibacter smit ...19958566705
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
physiological ecology of methanobrevibacter cuticularis sp. nov. and methanobrevibacter curvatus sp. nov., isolated from the hindgut of the termite reticulitermes flavipes.two morphologically distinct, h2- and co2-utilizing methanogens were isolated from gut homogenates of the subterranean termite, reticulitermes-flavipes (kollar) (rhinotermitidae). strain rfm-1 was a short straight rod (0.4 by 1.2 micron), whereas strain rfm-2 was a slightly curved rod (0.34 by 1.6 microns) that possessed polar fibers. their morphology, gram-positive staining reaction, resistance to cell lysis by chemical agents, and narrow range of utilizable substracts were typical of species b ...19968837417
the role of ciliate protozoa in the lysis of methanogenic archaea in rumen fluid.predation by ciliate protozoa can account for 90% of the eubacterial protein turnover in the rumen. however, little is known about the factors affecting the lysis of archaea in rumen fluid. bacterial lysis was followed from the release of acid-soluble 14c from 14c leucine-labelled bacteria. the rumen methanogen methanobrevibacter mf1 was broken down more rapidly than other non-ruminal archaea in rumen fluid withdrawn from sheep harbouring either a mixed protozoa population or monofaunated with p ...19968987902
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
h2/co2 metabolism in acetogenic bacteria isolated from the human colon.the present work reports on autotrophic metabolism in four h2/co2-utilizing acetogenic bacteria isolated from the human colon (two clostridium species, one streptococcus species, and ruminococcus hydrogenotrophicus). h2/co2-utilization by these human acetogenic strains occurred during both exponential and stationary phases of growth. acetate was the major metabolite produced by all isolates following the stoichiometric equation of reductive acetogenesis. furthermore, the ability of these acetoge ...199716887606
effect of methanobrevibacter sp mf1 inoculation on glycoside hydrolase and polysaccharide depolymerase activities, wheat straw degradation and volatile fatty acid concentrations in the rumen of gnotobiotically-reared lambs.four naturally born lambs were placed in sterile isolators 24 h after birth before the natural establishment of cellulolytic microorganisms and archaea methanogens. at the age of 6 weeks they were inoculated with pure cultures of the strains fd1 and 007 of ruminococcus flavefaciens and at the age of 4 months with a pure culture of methanobrevibacter sp. mf1. following the establishment of mf1, the population of r. flavefaciens slightly increased in the rumen of the four lambs, there was also an ...199716887613
anaerobic transformation of furfural by methanococcus deltae (delta)lh.methanococcus deltae (delta)lh was grown on h(inf2)-co(inf2) in the presence of various concentrations of furfural. furfural at higher concentrations, namely, 20 and 25 mm, inhibited growth of this organism. at concentration of 5 and 10 mm, no inhibition of growth was observed. the other methanogens in this study were not inhibited by 10 mm furfural. among the methanogens tested, m. deltae was capable of transforming furfural, whereas methanobacterium thermoautotrophicum marburg, methanosarcina ...199716535618
archaeosomes as novel antigen delivery systems.the humoral immune response mounted in balb/c mice against bovine serum albumin or cholera toxin b subunit was compared when the antigens were associated with liposomes composed of either archaeal ether lipids or conventional lipids. antibody titres in sera from mice immunised intraperitoneally were elevated to an extent comparable to those achieved with freund's adjuvant by encapsulating bovine serum albumin in archaeal lipid vesicles (archaeosomes) of about 200 nm diameter. comparison among si ...19979297816
methanobrevibacter filiformis sp. nov., a filamentous methanogen from termite hindguts.a morphologically distinct, filamentous methanogen was isolated from hindguts of the subterranean termite, reticulitermes flavipes (kollar) (rhinotermitidae), wherein it was part of the microbiota colonizing the hindgut wall. individual filaments of strain rfm-3 were 0.23-0.28 micron in diameter and usually > 50 micron in length and aggregated into flocs that were often >/= 0.1 mm in diameter. optimal growth of strain rfm-3 was obtained at ph 7.0-7.2 and 30 degrees c with a yeast-extract-supplem ...19989531629
phylogenetic analysis of methanobrevibacter isolated from feces of humans and other animals.comparative 16s rrna gene sequence and genomic dna reassociation analyses were used to assess the phylogenetic relationships of methanobrevibacter fecal isolates. the 16s rrna gene sequences of methanobrevibacter smithii strain ps and the human fecal isolates b181 and ali were essentially identical, and their genomic dna reassociated at values greater than 94%. the analysis of 16s rrna sequences of the horse, pig, cow, rat, and goose fecal isolates confirm that they are members of the genus meth ...19989560420
methanogenic bacteria: presence in foodstuffs.methanogenic bacteria are anaerobic, oxygen-intolerant microorganisms, and it is only by studying the different habitats of such bacteria that fundamental information about their ecology becomes available. this research has evaluated methanogenic bacteria in apparently aerobic ecosystems, in foodstuffs not subjected to chemical-physical reclamation processes, where the presence of methanogenic bacteria has never been investigated. methanogenic bacteria, ascribable to the methanogenium, methanoba ...19989637008
decompression sickness risk in rats by microbial removal of dissolved gas.we present a method for reducing the risk of decompression sickness (dcs) in rats exposed to high pressures of h2. suspensions of the human colonic microbe methanobrevibacter smithii were introduced via a colonic cannula into the large intestines of the rats. while the rats breathed h2 in a hyperbaric chamber, the microbe metabolized some of the h2 diffusing into the intestine, converting h2 and co2 to methane and water. rate of release of methane from the rats, which was monitored by gas chroma ...19989728062
phylogenetic diversity of symbiotic methanogens living in the hindgut of the lower termite reticulitermes speratus analyzed by pcr and in situ hybridization.a phylogenetic analysis of the sequences of 60 clones of archaeal small-subunit rrna genes amplified from the termite reticulitermes speratus revealed that most of them (56 clones) clustered in the genus methanobrevibacter. three clones were classified in the order thermoplasmales. the methanobrevibacter-related symbionts were detected by in situ hybridization analysis.19999925625
phylogenetic relationships of symbiotic methanogens in diverse termites.termites harbor symbiotic microorganisms in their gut which emit methane. the phylogeny of the termite methanogens was inferred without cultivation based on nucleotide sequences of pcr-amplified 16s ribosomal rna genes. seven methanogen sequences from four termite species were newly isolated, and together with those previously published, these sequences were phylogenetically compared. the termite methanogen sequences were divided into three clusters. two clusters of sequences, derived from the g ...199910077839
phylogenetic study of methanogens associated with rumen ciliates.the phylogeny of methanogenic archaea associated with ciliate protozoa in a sheep rumen was investigated. ruminal ciliate protozoa were exhaustively washed and mixtures of genomic dna extracted. archaea-specific nested pcr amplification was conducted with the ciliate genomic mixture. the resultant small subunit (16s) ribosomal rna gene (ssu rdna) was cloned into escherichia coli jm 109. many methanogens were still observed on and/or in ciliate cells by fluorescent microscopy even after exhaustiv ...199910441724
phylogenetic diversity of methanogenic archaea in swine waste storage pits.total dna was isolated from swine feces and a swine waste storage pit and used as templates for pcr amplification of archaeal 16 rdna using specific primers. only the sample from the center of the waste pit produced a pcr product. dna sequence analyses of random clones demonstrated a variety of methanogenic archaea. six groups of sequences were identified, including those similar to methanobrevibacter sp., methanocorpusculum sp., and methanoculleus sp. three groups of sequences represented unide ...199910518719
a structural comparison of the total polar lipids from the human archaea methanobrevibacter smithii and methanosphaera stadtmanae and its relevance to the adjuvant activities of their liposomes.mice were immunized with bovine serum albumin (bsa) entrapped within archaeosomes (i.e. liposomes) composed of the total polar lipids (tpl) from the two methanogenic archaea common to the human digestive tract. methanobrevibacter smithii archaeosomes boosted serum anti-bsa antibody to titers comparable to those achieved with freund's adjuvant, whereas methanosphaera stadtmanae archaeosomes were relatively poor adjuvants. an explanation for this difference was sought by analysis of the polar lipi ...199910521711
isolation of methanobrevibacter sp. as a ciliate-associated ruminal methanogen. 199912501401
the effect of a methanogen, methanobrevibacter smithii, on the growth rate, organic acid production, and specific atp activity of three predominant ruminal cellulolytic bacteria.three predominant ruminal cellulolytic organisms, fibrobacter succinogenes s85, ruminococcus albus 8, and r. flavefaciens fd-1, were cultured with a methanogen, methanobrevibacter smithii. growth rates, bacterial protein, organic acids, and methane production were measured. when grown in diculture with the methanogen, a fermentative advantage was observed with f. succinogenes s85 as seen by an increase in specific rate of atp production and organic acid concentration. the introduction of the met ...200010679049
effects of the fusarium spp. mycotoxins fusaric acid and deoxynivalenol on the growth of ruminococcus albus and methanobrevibacter ruminantium.the fusarium spp. mycotoxins fusaric acid and deoxynivalenol (don) were tested for antimicrobial activity against ruminococcus albus and methanobrevibacter ruminantium. the growth of both organisms was inhibited by fusaric acid as low as 15 micrograms/ml (84 microm) but not by don, at levels as high as 100 micrograms/ml (338 microm). no synergistic inhibitory effect was observed with don plus fusaric acid. neither organism was able to adapt to the fusaric acid and responses of each organism to t ...200010941514
phylogenetic analysis of methanogens in sheep rumen ecosystem and detection of methanomicrobium mobile by fluorescence in situ hybridization.the population of methanogens in the sheep rumen microbial ecosystem was studied by using 16s rdna cloning analysis, epifluorescence microscopy (which detects autofluorescence of a specific cofactor f420 in methanogens) and the 16s rrna-targeted in situ hybridization technique. the 16s rdna clone libraries were constructed by pcr amplification with an archaea-specific primer set and partial sequencing of the clonal 16s rdnas was done. phylogenetic analysis indicated that the clones were affiliat ...200010993166
anaerobic bioconversion of cellulose by ruminococcus albus, methanobrevibacter smithii, and methanosarcina barkeri.a system is described that combines the fermentation of cellulose to acetate, ch4, and co2 by ruminococcus albus and methanobrevibacter smithii with the fermentation of acetate to ch4 and co2 by methanosarcina barkeri to convert cellulose to ch4 and co2. a cellulose-containing medium was pumped into a co-culture of the cellulolytic r. albus and the h2-using methanogen, mb. smithii. the effluent was fed into a holding reservoir, adjusted to ph 4.5, and then pumped into a culture of ms. barkeri ma ...200011092623
molecular phylogeny of methanogens associated with flagellated protists in the gut and with the gut epithelium of termites.the molecular phylogeny of methanogenic archaea associated with the flagellated protist species dinenympha and microjoenia in the gut of termites, reticulitermes speratus and hodotermopsis sjoestedti, and those attached to the gut epithelium was examined based on pcr-amplified small-subunit ribosomal rna genes. the sequences identified were classified into six groups within the genus methanobrevibacter, including groups of yet uncharacterized novel species. closely related methanogens were share ...200011098074
identification of archaeal rdna from subgingival dental plaque by pcr amplification and sequence analysis.a pcr assay for the amplification of small subunit ribosomal dna (ssu rdna) of euryarchaea was developed and used to detect archaeal rdna in 37 (77%) out of 48 pooled subgingival plaque samples from 48 patients suffering from periodontal disease. one major group of cloned periodontal sequences was identical to methanobrevibacter oralis and a second minor group to methanobrevibacter smithii. these two groups and a third novel group were found to be more than 98% similar to each other over an 0.65 ...200111267768
isolation and antimicrobial susceptibility testing of fecal strains of the archaeon methanobrevibacter smithii.the archaeon methanobrevibacter smithii is regarded as part of the indigenous microflora of the human intestine but may be connected with pathological conditions. the microbe is extremely oxygen intolerant and is not detectable by anaerobic culture techniques for bacteria. accordingly, to date quantitative antimicrobial susceptibility data of human isolates are missing.200111306786
steady-state and time-resolved spectroscopy of f420 extracted from methanogen cells and its utility as a marker for fecal contamination.methanogenic bacteria, which are common inhabitants of the animal digestive tract, contain the fluorescent compound f420 (coenzyme 420), a 7,8-didemethyl-8-hydroxy-5-deazariboflavin chromophore. f420 was characterized as an initial step in determining if this compound would be useful as a fluorescent marker for the detection of fecal and ingesta contamination. using a single anion exchange chromatographic process, f420 was separated from other cell components of a methanobrevibacter sp. cell cul ...200111312822
phylogenetic analysis of methanogens from the bovine rumen.interest in methanogens from ruminants has resulted from the role of methane in global warming and from the fact that cattle typically lose 6 % of ingested energy as methane. several species of methanogens have been isolated from ruminants. however they are difficult to culture, few have been consistently found in high numbers, and it is likely that major species of rumen methanogens are yet to be identified.200111384509
phylogenetic analysis of archaeal 16s rrna libraries from the rumen suggests the existence of a novel group of archaea not associated with known methanogens.molecular diversity of rumen archaea was analyzed by pcr amplification and sequencing of two 16s rrna clone libraries prepared from the bovine rumen fluid using two different archaea-specific primer sets. the first library of 19 clones which was generated with primers d30 and d33, produced essentially two groups of sequences, one affiliated with methanomicrobium mobile (21% of clones) and the other -- with the uncultured archaeal sequences from anaerobic digester, which are distantly associated ...200111410351
inhibition of growth of methane-producing bacteria of the ruminant forestomach by hydroxymethylglutaryl-scoa reductase inhibitors.two hydroxymethylglutaryl-scoa (hmg-coa) reductase inhibitors, mevastatin and lovastatin, inhibited the in vitro growth and production of ch4 of strains of methanobrevibacter isolated from the rumen. mevastatin or lovastatin did not inhibit growth of species of rumen bacteria that are essential for fermenting cellulose, starch and other plant polysaccharides to acetate, propionate, and butyrate. approximately 4 nmol of lovastatin per milliliter resulted in 50% growth inhibition of methanobreviba ...200111417704
characterization of a heme-dependent catalase from methanobrevibacter arboriphilus.recently it was reported that methanogens of the genus methanobrevibacter exhibit catalase activity. this was surprising, since methanobrevibacter species belong to the order methanobacteriales, which are known not to contain cytochromes and to lack the ability to synthesize heme. we report here that methanobrevibacter arboriphilus strains az and dh1 contained catalase activity only when the growth medium was supplemented with hemin. the heme catalase was purified and characterized, and the enco ...200111425719
increasing activity of h(2)-metabolizing microbes lowers decompression sickness risk in pigs during h(2) dives.the risk of decompression sickness (dcs) was modulated by varying the biochemical activity used to eliminate some of the hydrogen (h(2)) stored in the tissues of pigs (19.4 +/- 0.2 kg) during hyperbaric exposures to h(2). treated pigs (n = 16) received intestinal injections of methanobrevibacter smithii, a microbe that metabolizes h(2) to water and ch(4). surgical controls (n = 10) received intestinal injections of saline, and an additional control group (n = 10) was untreated. pigs were placed ...200111717238
interspecies h2 transfer in cellulose degradation between fibrolytic bacteria and h2-utilizing microorganisms from the human colon.interspecies h2 transfer between two newly isolated fibrolytic strains (18p13 and 18p16) and h2-utilizing methanogen or acetogen from the human colon was investigated during in vitro cellulose degradation. both h2-consuming microorganisms utilized efficiently h2 produced from cellulose fermentation by the fibrolytic species. h2 utilization by methanobrevibacter smithii did not change the metabolism and the cellulolytic activity of strain 18p16 whereas it induced a metabolic shift in strain 18p13 ...200111750804
characterization of a 4-methylbenzoate-degrading methanogenic consortium as determined by small-subunit rdna sequence analysis.a methanogenic consortium that degrades 4-methylbenzoate (mba) as the sole carbon and energy source was successfully enriched in an upflow anaerobic sludge bed bioreactor and studied. electron microscopic observation showed that long rods with a distinct collar feature resembling desulfomonile tiedjei rods were the predominant population, and that these rods formed a close spatial orientation with methanobrevibacter-like bacteria. in addition, thin filaments and bamboo-shaped filaments that high ...200116233021
the effect of polymer addition on granulation in an anaerobic baffled reactor (abr). part ii: compartmentalization of bacterial populations.the microbial ecology of wastewater treatment plants remains one of the least understood aspects in both aerobic and anaerobic systems, despite the fact that both processes are ultimately dependent on an active biomass for operational efficiency. ultimately, future developments in anaerobic treatment processes will require a much greater understanding of the fundamental relationships between bacterial populations within the biomass if optimum process efficiency is to be fully realised. this stud ...200211848365
degradation of fresh ryegrass by methanogenic co-cultures of ruminal fungi grown in the presence or absence of fibrobacter succinogenes.the ability of five ruminal fungi in syntrophic co-culture with the methanogen methanobrevibacter smithii to degrade perennial ryegrass ( lolium perenne) stem fragments and leaf blades was studied to determine the susceptibilities of non-autoclaved fresh tissues to fungal degradation. autoclaving did not significantly increase fungal degradation of stem fragments but strongly increased degradation of leaf blades by a species of caecomyces. in methanogenic co-cultures, non-autoclaved stem fragmen ...200212029527
description of methanobrevibacter gottschalkii sp. nov., methanobrevibacter thaueri sp. nov., methanobrevibacter woesei sp. nov. and methanobrevibacter wolinii sp. nov..formal nomenclature is proposed for five methanogens, isolated from horse, pig, cow, goose and sheep faeces, that represent four novel species of the genus methanobrevibacter. the four species, methanobrevibacter gottschalkii sp. nov., methanobrevibacter thaueri sp. nov., methanobrevibacter woesei sp. nov. and methanobrevibacter wolinii sp. nov., are distinguished from each other by a lack of genomic dna reassociation and from previously described members of the genus on the basis of differences ...200212054244
[catalase and superoxide dismutase in the cells of strictly anaerobic microorganisms].strictly anaerobic microorganisms relating to various physiological groups were screened for catalase and superoxide dismutase (sod) activity. all of the investigated anaerobes possessed the sod activity, necessary for protection against toxic products of oxygen reduction. high specific activities of sod were found in acetobacterium woodii and acetobacterium wieringae. most of the investigated clostridia and acetogens were catalase-negative. a significant activity of catalase was found in thermo ...200212138753
methanobrevibacter acididurans sp. nov., a novel methanogen from a sour anaerobic digester.a novel acid-tolerant, hydrogenotrophic methanogen, isolate atmt, was obtained from an enrichment performed at ph 5.0 using slurry from an acidogenic digester running on alcohol distillery waste. the original ph of the slurry was 5.7 and the volatile fatty acid concentration was 9000 p.p.m. cells of isolate atmt were gram-positive, non-motile and 0.3-0.5 microm in size. they did not form spores. the isolate could grow in the ph range 5.0-7.5, with maximum growth at ph 6.0. the optimum temperatur ...200212148611
modulation of decompression sickness risk in pigs with caffeine during h(2) biochemical decompression.in h(2) biochemical decompression, h(2)-metabolizing intestinal microbes remove gas stored in tissues of animals breathing hyperbaric h(2), thereby reducing decompression sickness (dcs) risk. we hypothesized that increasing intestinal perfusion in pigs would increase the activity of intestinal methanobrevibacter smithii, lowering dcs incidence further. pigs (sus scrofa, 17-23 kg, n = 20) that ingested caffeine (5 mg/kg) increased o(2) consumption rate in 1 atm air by ~20% for at least 3 h. pigs ...200212381741
safety of archaeosome adjuvants evaluated in a mouse model.archaeosomes, liposomes prepared from the polar ether lipids extracted from archaea, demonstrate great potential as immunomodulating carriers of soluble antigens, promoting humoral and cell mediated immunity in the vaccinated host. the safety of unilamellar archaeosomes prepared from the total polar lipids (tpl) of halobacterium salinarum, methanobrevibacter smithii or thermoplasma acidophilum was evaluated in female balb/c mice using ovalbumin (ova) as the model antigen. groups of 6-8 mice were ...200212519630
archaeosomes induce enhanced cytotoxic t lymphocyte responses to entrapped soluble protein in the absence of interleukin 12 and protect against tumor challenge.archaeosome adjuvants formulated as archaeal ether glycerolipid vesicles induce strong cd4(+) as well as cd8(+) ctl responses to entrapped soluble antigens. immunization of mice with ovalbumin (ova) entrapped in archaeosomes composed of the total polar lipids of methanobrevibacter smithii resulted in a potent ova-specific cd8(+) t-cell response, and subsequently, the mice dramatically resisted solid tumor growth of ova-expressing eg.7 cells and lung metastasis of b16ova melanoma cells. prophylac ...200312750276
improved strategy for presumptive identification of methanogens using 16s riboprinting.the predicted 16s riboprint patterns of 10 restriction endonucleases for 26 diverse methanogens were compared to actual patterns produced on agarose gels. the observed patterns corroborated the expected riboprints. our analyses confirmed that the endonuclease haeiii gave the best results generating 15 different riboprint sets. six of these 15 riboprints represented more than one strain. of these, three riboprint sets were further differentiated: methanomicrobium mobile, methanolacinia paynteri, ...200314529955
archaeobacterial ether lipid liposomes as vaccine adjuvants. 200314714403
archaeosomes varying in lipid composition differ in receptor-mediated endocytosis and differentially adjuvant immune responses to entrapped antigen.archaeosomes prepared from total polar lipids extracted from six archaeal species with divergent lipid compositions had the capacity to deliver antigen for presentation via both mhc class i and class ii pathways. lipid extracts from halobacterium halobium and from halococcus morrhuae strains 14039 and 16008 contained archaetidylglycerol methylphosphate and sulfated glycolipids rich in mannose residues, and lacked archaetidylserine, whereas the opposite was found in methanobrevibacter smithii, me ...200315803661
archaeosomes as self-adjuvanting delivery systems for cancer vaccines.archaeal ether glycerolipid vesicles (archaeosomes) efficiently deliver exogenous antigen for induction of humoral and cell-mediated immunity. because induction of cd8 cytotoxic t cells is critical for protective vaccination against tumors, we compared the ability of various archaeosome lipid compositions to evoke a strong cd8 ctl response to entrapped antigen. subcutaneous immunization of mice with ovalbumin (ova) entrapped in all archaeosome lipid compositions evoked a primary (day 10) splenic ...200315203920
phosphatidylserine receptor-mediated recognition of archaeosome adjuvant promotes endocytosis and mhc class i cross-presentation of the entrapped antigen by phagosome-to-cytosol transport and classical processing.archaeal isopranoid glycerolipid vesicles (archaeosomes) serve as strong adjuvants for cell-mediated responses to entrapped ag. we analyzed the processing pathway of ova entrapped in archaeosomes composed of methanobrevibacter smithii lipids, high in archaetidylserine (ova-archaeosomes). in vitro, ova-archaeosomes stimulated spleen cells from ova-tcr-transgenic mice, d011.10 (cd4(+) cells expressing ova(323-339) tcr) or ot1 (>90% cd8(+) ova(257-264) cells), indicating both mhc class i and ii pre ...200415210818
comparison of euryarchaea strains in the guts and food-soil of the soil-feeding termite cubitermes fungifaber across different soil types.termites are an important component of tropical soil communities and have a significant effect on the structure and nutrient content of soil. digestion in termites is related to gut structure, gut physicochemical conditions, and gut symbiotic microbiota. here we describe the use of 16s rrna gene sequencing and terminal-restriction fragment length polymorphism (t-rflp) analysis to examine methanogenic archaea (ma) in the guts and food-soil of the soil-feeder cubitermes fungifaber sjostedt across ...200415240259
microbial monitoring by molecular tools of a two-phase anaerobic bioreactor treating fruit and vegetable wastes.microbial consortia in a two-phase, anaerobic bioreactor using a mixture of fruit and vegetable wastes were established. bacterial and archaeal communities obtained by a culture-independent approach based on single strand conformation polymorphism analysis of total 16s rdna showed the adaptation of the microflora to the process parameters. throughout the 90 d of the study, the species composition of the bacterial community changed significantly. bacterial 16s rdna showed at least 7 different maj ...200415269562
effects of several inhibitors on pure cultures of ruminal methanogens.to examine the effects of five inhibitors of methanogenesis, 2-bromoethanesulphonate (bes), 3-bromopropanesulphonate (bps), lumazine, propynoic acid and ethyl 2-butynoate, on ch4 production of the ruminal methanogens methanobrevibacter ruminantium, methanosarcina mazei and methanomicrobium mobile.200415281932
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