| 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 ... | 1992 | 1550443 |
| 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 ... | 1991 | 1872605 |
| 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 ... | 1990 | 2082826 |
| 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 ... | 1990 | 2199527 |
| 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 ... | 1990 | 2227350 |
| 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 ... | 1989 | 2722716 |
| 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 ... | 1985 | 2993814 |
| 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 ... | 1987 | 3036807 |
| 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 ... | 1988 | 3170480 |
| 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 ... | 1988 | 3255348 |
| 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 ... | 1988 | 3355146 |
| 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 ... | 1986 | 3721294 |
| 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 ... | 1985 | 3936936 |
| 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. | 1984 | 6486788 |
| 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 ... | 1982 | 6798932 |
| 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. | 1983 | 6824322 |
| 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 ... | 1982 | 7065811 |
| 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 ... | 1981 | 7298577 |
| 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 ... | 1995 | 8566705 |
| 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 ... | 1997 | 9297816 |
| 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 ... | 1998 | 9560420 |
| 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 ... | 1998 | 9637008 |
| 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 ... | 1998 | 9728062 |
| 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 ... | 1999 | 10441724 |
| 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 ... | 1999 | 10521711 |
| 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 ... | 2000 | 10679049 |
| 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 ... | 2000 | 10993166 |
| 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 ... | 2000 | 11092623 |
| 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 ... | 2001 | 11267768 |
| 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. | 2001 | 11306786 |
| 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 ... | 2001 | 11717238 |
| 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 ... | 2001 | 11750804 |
| 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 ... | 2002 | 12029527 |
| 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 ... | 2002 | 12381741 |
| 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 ... | 2002 | 12519630 |
| 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 ... | 2003 | 12750276 |
| 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 ... | 2003 | 15203920 |
| 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 ... | 2004 | 15210818 |
| archaeosomes as adjuvants for combination vaccines. | the present study evaluated the potential of archaesomes, prepared from the total polar lipids extracted from methanobrevibacter smithii, as adjuvants for combination (multivalent) vaccines. groups of balb/c mice were immunized subcutaneously at day 0 and 21 with one of the following vaccines: trivalent vaccine formulated by the simultaneous co-encapsulation of bovine serum albumine (bsa), ovalbumin (ova) and hen egg lysozyme (hel) into archaeosomes (cec vaccine); an univalent archaeosome vaccin ... | 2004 | 15676126 |
| detection of methanogens and proteobacteria from a single cell of rumen ciliate protozoa. | rumen ciliate-associated bacteria and methanogenic archaea were analyzed by a 16s rrna gene retrieved from a single cell of polyplastron multivesiculatum, isotricha intestinalis, and ophryoscolex purkynjei. rumen fluid was taken from a ruminally fistulated goat to prepare a ciliate fraction. ciliate mixtures were incubated under mixtures of antibiotics for 48 h to eliminate extracellular bacteria. individual cells of rumen ciliates were selected under microscopic observation after fixation with ... | 2004 | 15754246 |
| 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 ... | 2003 | 15803661 |
| development of methods for the detection and quantification of 7alpha-dehydroxylating clostridia, desulfovibrio vulgaris, methanobrevibacter smithii, and lactobacillus plantarum in human feces. | mounting evidence suggests a relationship between bacterial metabolism of certain dietary and endogenous factors and the development of colorectal cancer. deoxycholic acid (dca) is a well studied co-carcinogen and bio-transformation product of 7alpha-dehydroxylating clostridia. h2s is a cytotoxic metabolite produced primarily by sulfate-reducing bacteria (srb). the production of methane indicates low levels of active srb. lactic acid bacteria (lab) have received attention recently due to their p ... | 2005 | 15963794 |
| 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 ... | 1981 | 16345708 |
| 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 ... | 1988 | 16347581 |
| 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 ... | 1989 | 16347990 |
| 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 ... | 1990 | 16348244 |
| 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 ... | 1991 | 16348508 |
| 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 ... | 1993 | 16349022 |
| h2 and acetate transfers during xylan fermentation between a butyrate-producing xylanolytic species and hydrogenotrophic microorganisms from the human gut. | the aim of this work was to investigate in vitro interrelationships during xylan fermentation between an h2 and butyrate-producing xylanolytic species recently isolated in our laboratory from human faeces and identified as roseburia intestinalis and the h2-utilizing acetogen ruminococcus hydrogenotrophicus or the methanogen methanobrevibacter smithii. h2 transfer between m. smithii or ru. hydrogenotrophicus and the xylanolytic species was evidenced, confirming the great potential of these h2-con ... | 2006 | 16451188 |
| salt tolerance of archaeal extremely halophilic lipid membranes. | the membranes of extremely halophilic archaea are characterized by the abundance of a diacidic phospholipid, archaetidylglycerol methylphosphate (pgp-me), which accounts for 50-80 mol% of the polar lipids, and by the absence of phospholipids with choline, ethanolamine, inositol, and serine head groups. these membranes are stable in concentrated 3-5 m nacl solutions, whereas membranes of non-halophilic archaea, which do not contain pgp-me, are unstable and leaky under such conditions. by x-ray di ... | 2006 | 16484230 |
| a humanized gnotobiotic mouse model of host-archaeal-bacterial mutualism. | our colons harbor trillions of microbes including a prominent archaeon, methanobrevibacter smithii. to examine the contributions of archaea to digestive health, we colonized germ-free mice with bacteroides thetaiotaomicron, an adaptive bacterial forager of the polysaccharides that we consume, with or without m. smithii or the sulfate-reducing bacterium desulfovibrio piger. whole-genome transcriptional profiling of b. thetaiotaomicron, combined with mass spectrometry, revealed that, unlike d. pig ... | 2006 | 16782812 |
| detection of the nifh gene of methanobrevibacter smithii: a potential tool to identify sewage pollution in recreational waters. | the goal of this study was to develop and test the efficacy of a pcr assay for the environmental detection of the nifh gene of methanobrevibacter smithii, a methanogen found in human faeces and sewage. | 2006 | 16834590 |
| 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 ... | 1997 | 16887606 |
| in vitro bacterial growth and in vivo ruminal microbiota populations associated with bloat in steers grazing wheat forage. | the role of ruminal bacteria in the frothy bloat complex common to cattle grazing winter wheat has not been previously determined. two experiments, one in vitro and another in vivo, were designed to elucidate the effects of fresh wheat forage on bacterial growth, biofilm complexes, rumen fermentation end products, rumen bacterial diversity, and bloat potential. in exp. 1, 6 strains of ruminal bacteria (streptococcus bovis strain 26, prevotella ruminicola strain 23, eubacterium ruminantium b1c23, ... | 2006 | 16971591 |
| rapid clonal expansion and prolonged maintenance of memory cd8+ t cells of the effector (cd44highcd62llow) and central (cd44highcd62lhigh) phenotype by an archaeosome adjuvant independent of tlr2. | vaccines capable of eliciting long-term t cell immunity are required for combating many diseases. live vectors can be unsafe whereas subunit vaccines often lack potency. we previously reported induction of cd8(+) t cells to ag entrapped in archaeal glycerolipid vesicles (archaeosomes). in this study, we evaluated the priming, phenotype, and functionality of the cd8(+) t cells induced after immunization of mice with ova-methanobrevibacter smithii archaeosomes (ms-ova). a single injection of ms-ov ... | 2007 | 17277146 |
| 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 ... | 2008 | 17379394 |
| analysis of methanogen diversity in the rumen using temporal temperature gradient gel electrophoresis: identification of uncultured methanogens. | a temporal temperature gradient gel electrophoresis (ttge) method was developed to determine the diversity of methanogen populations in the rumen. tests with amplicons from genomic dna from 12 cultured methanogens showed single bands for all strains, with only two showing apparently comigrating bands. fingerprints of methanogen populations were analyzed from dna extracted from rumen contents from two cattle and four sheep grazing pasture. for one sheep, dilution cultures selective for methanogen ... | 2007 | 17431710 |
| postinoculation protozoan establishment and association patterns of methanogenic archaea in the ovine rumen. | association patterns between archaea and rumen protozoa were evaluated by analyzing archaeal 16s rrna gene clone libraries from ovine rumen inoculated with different protozoa. five protozoan inoculation treatments, fauna free (negative control), holotrich and cellulolytic protozoa, isotricha and dasytricha spp., entodinium spp., and total fauna (type a) were tested. we used denaturing gradient gel electrophoresis, quantitative pcr, and phylogenetic analysis to evaluate the impact of the protozoa ... | 2007 | 17513586 |
| genomic and metabolic adaptations of methanobrevibacter smithii to the human gut. | the human gut is home to trillions of microbes, thousands of bacterial phylotypes, as well as hydrogen-consuming methanogenic archaea. studies in gnotobiotic mice indicate that methanobrevibacter smithii, the dominant archaeon in the human gut ecosystem, affects the specificity and efficiency of bacterial digestion of dietary polysaccharides, thereby influencing host calorie harvest and adiposity. metagenomic studies of the gut microbial communities of genetically obese mice and their lean litte ... | 2007 | 17563350 |
| evidence of increased diversity of methanogenic archaea with plant extract supplementation. | this study evaluated the effects of selected essential oils on archaeal communities using the ovine rumen model. forty weaned canadian arcott ewes, fed with barley-based diet, were allotted to one of three essential oil supplementation treatments or a control (10 ewes per treatment) for 13 weeks. the treatments were cinnamaldehyde, garlic oil, juniper berry oil, and a control with no additive. rumen content was sampled after slaughter and grouped by treatment by combining subsamples from each an ... | 2008 | 18075710 |
| archaeosome adjuvants: immunological capabilities and mechanism(s) of action. | archaeosomes (liposomes comprised of glycerolipids of archaea) constitute potent adjuvants for the induction of th1, th2 and cd8(+) t cell responses to the entrapped soluble antigen. archaeal lipids are uniquely constituted of ether-linked isoprenoid phytanyl cores conferring stability to the membranes. additionally, varied head groups displayed on the glycerol-lipid cores facilitate unique immunostimulating interactions with mammalian antigen-presenting cells (apcs). the polar lipid from the ar ... | 2008 | 18343538 |
| volatilisation of metals and metalloids: an inherent feature of methanoarchaea? | as shown by recent studies, anaerobic members of archaea and bacteria are involved in processes that transform ionic species of metals and metalloids (arsenic, antimony, bismuth, selenium, tellurium and mercury) into volatile and mostly toxic derivatives (mainly methyl derivatives or hydrides). since the fact that these transformations proceed in both environmental settings and in parts of the human body, we have to consider that these processes also interfere directly with human health. the div ... | 2008 | 18396004 |
| human methanogen diversity and incidence in healthy and diseased colonic groups using mcra gene analysis. | the incidence and diversity of human methanogens are insufficiently characterised in the gastrointestinal tract of both health and disease. a pcr and clone library methodology targeting the mcra gene was adopted to facilitate the two-fold aim of surveying the relative incidence of methanogens in health and disease groups and also to provide an overview of methanogen diversity in the human gastrointestinal tract. | 2008 | 18492229 |
| a putative new order of methanogenic archaea inhabiting the human gut, as revealed by molecular analyses of the mcra gene. | the diversity of methanogenic archaea from the gut of 6 humans was investigated by targeting mcra, a molecular metabolic marker of methanogenesis. three operational taxonomic units (otus) were recovered from about 400 clones analyzed, two of which were attributed to the expected methanobacteriales methanobrevibacter smithii (4 volunteers) and methanosphaera stadtmanae (1 volunteer). the third otu (1 volunteer) corresponded to a distant phylotype that does not cluster with any of the five methano ... | 2008 | 18644435 |
| safety of intranasally administered archaeal lipid mucosal vaccine adjuvant and delivery (amvad) vaccine in mice. | the safety profile of a recently described novel archaeal lipid mucosal vaccine adjuvant and delivery (amvad) system capable of eliciting robust antigen-specific mucosal and systemic immune responses was evaluated in female balb/c mice (10/group) using ovalbumin (ova) antigen. mice were intranasally immunized (0, 7, and 21 days) with a vaccine comprising 1 microg ova (0.05 mg/kg body weight) formulated in 0.04 mg total polar lipids extract (2.17 mg/kg body weight) of methanobrevibacter smithii c ... | 2008 | 18821397 |
| effects of the gut microbiota on host adiposity are modulated by the short-chain fatty-acid binding g protein-coupled receptor, gpr41. | the distal human intestine harbors trillions of microbes that allow us to extract calories from otherwise indigestible dietary polysaccharides. the products of polysaccharide fermentation include short-chain fatty acids that are ligands for gpr41, a g protein-coupled receptor expressed by a subset of enteroendocrine cells in the gut epithelium. to examine the contribution of gpr41 to energy balance, we compared gpr41-/- and gpr41+/+ mice that were either conventionally-raised with a complete gut ... | 2008 | 18931303 |
| quantification of human polyomaviruses jc virus and bk virus by taqman quantitative pcr and comparison to other water quality indicators in water and fecal samples. | in the united states, total maximum daily load standards for bodies of water that do not meet bacterial water quality standards are set by each state. the presence of human polyomaviruses (hpyvs) can be used as an indicator of human-associated sewage pollution in these waters. we have developed and optimized a taqman quantitative pcr (qpcr) assay based on the conserved t antigen to both quantify and simultaneously detect two hpyvs; jc virus and bk virus. the qpcr assay was able to consistently q ... | 2009 | 19346361 |
| validation and field testing of library-independent microbial source tracking methods in the gulf of mexico. | water quality is frequently impacted by microbial pollution from human and animal feces. microbial source tracking (mst) can identify dominant pollution sources and improve assessment of health risk compared to indicator bacteria alone. this study aims to standardize and validate mst methods across laboratories in coastal gulf of mexico states. three laboratories evaluated library-independent mst methods for human sewage detection via conventional pcr: (1) human-associated bacteroidales, (2) hum ... | 2009 | 19595426 |
| t-rflp-based mcra gene analysis of methanogenic archaea in association with oral infections and evidence of a novel methanobrevibacter phylotype. | increasing evidence suggests a role for methanogenic archaea (methanogens) in human health and disease via syntrophic interactions with bacteria. here we assessed the prevalence and distribution of methanogens and possible associations with bacteria in oral biofilms. | 2009 | 19702957 |
| high prevalence of methanobrevibacter smithii and methanosphaera stadtmanae detected in the human gut using an improved dna detection protocol. | the low and variable prevalence of methanobrevibacter smithii and methanosphaera stadtmanae dna in human stool contrasts with the paramount role of these methanogenic archaea in digestion processes. we hypothesized that this contrast is a consequence of the inefficiencies of current protocols for archaeon dna extraction. we developed a new protocol for the extraction and pcr-based detection of m. smithii and m. stadtmanae dna in human stool. | 2009 | 19759898 |
| monitoring bacterial community of human gut microbiota reveals an increase in lactobacillus in obese patients and methanogens in anorexic patients. | studies of the bacterial communities of the gut microbiota have revealed a shift in the ratio of firmicutes and bacteroidetes in obese patients. determining the variations of microbial communities in feces may be beneficial for the identification of specific profiles in patients with abnormal weights. the roles of the archaeon methanobrevibacter smithii and lactobacillus species have not been described in these studies. | 2009 | 19774074 |
| microbial equol production attenuates colonic methanogenesis and sulphidogenesis in vitro. | hydrogen gas produced during colonic fermentation is excreted in breath and flatus, or removed by hydrogen-consuming bacteria such as methanogens and sulphate-reducing bacteria. however, recent research has shown that h2 is also consumed by equol-producing bacteria during the reduction of daidzein into equol. in this study, the interactions between methanogens, sulphate-reducing, and equol-producing bacteria were investigated under in vitro simulated intestinal conditions. in the presence of dai ... | 2010 | 20298796 |
| characterization of variation in rumen methanogenic communities under different dietary and host feed efficiency conditions, as determined by pcr-denaturing gradient gel electrophoresis analysis. | understanding ruminal methanogens is essential for greenhouse gas mitigation, as well as for improving animal performance in the livestock industry. it has been speculated that ruminal methanogenic diversity affects host feed efficiency and results in differences in methane production. this study examined methanogenic profiles in the rumen using culture-independent pcr-denaturing gradient gel electrophoresis (pcr-dgge) analysis for 56 beef cattle which differed in feed efficiency, as well as die ... | 2010 | 20418436 |
| molecular profiling and identification of methanogenic archaeal species from rabbit caecum. | during a comparison of 16s rdna pcr-denaturant gradient gel electrophoresis (dgge) profiles of methanogenic archaea from rumen fluid, rabbit caecum and pig feces, a unique band common to all rabbit caecum samples was observed. dgge profiling also showed that the methanogen community from the new zealand white adult rabbits is different and less complex than the methanogen communities from the rumen and pig feces. small subunit ribosomal gene sequences of methanogenic archaea were subsequently re ... | 2010 | 20950344 |
| lack of correlation between enterococcal counts and the presence of human specific fecal markers in mississippi creek and coastal waters. | the objective of this study was to determine whether statistically valid correlations could be shown between enterococcal counts of samples from creek and coastal sites and the presence of two molecular, library-independent markers that specify human and/or sewage pollution. four hundred ninety samples were collected between august 2007 and april 2009 to determine enterococcal counts and the presence of genetic markers for the sewage indicator organisms methanobrevibacter smithii and bacteroidal ... | 2010 | 20950837 |
| a real-time qpcr assay for the detection of the nifh gene of methanobrevibacter smithii, a potential indicator of sewage pollution. | to develop a quantitative, real-time pcr assay to detect the nifh gene of methanobrevibacter smithii. methanobrevibacter smithii is a methanogenic archaea found in the intestinal tract of humans that may be a useful indicator of sewage pollution in water. | 2010 | 21070516 |
| the discussion goes on: what is the role of euryarchaeota in humans? | the human body (primarily the intestinal tract, the oral cavity, and the skin) harbours approximately 1,000 different bacterial species. however, the number of archaeal species known to colonize man seems to be confined to a handful of organisms within the class euryarchaeota (including methanobrevibacter smithii, m. oralis, and methanosphaera stadtmanae). in contrast to this conspicuously low diversity of archaea in humans their unique physiology in conjunction with the growing number of report ... | 2010 | 21253553 |
| pan-genome of the dominant human gut-associated archaeon, methanobrevibacter smithii, studied in twins. | the human gut microbiota harbors three main groups of h(2)-consuming microbes: methanogens including the dominant archaeon, methanobrevibacter smithii, a polyphyletic group of acetogens, and sulfate-reducing bacteria. defining their roles in the gut is important for understanding how hydrogen metabolism affects the efficiency of fermentation of dietary components. we quantified methanogens in fecal samples from 40 healthy adult female monozygotic (mz) and 28 dizygotic (dz) twin pairs, analyzed b ... | 2011 | 21317366 |
| archaeosome adjuvant overcomes tolerance to tumor-associated melanoma antigens inducing protective cd8 t cell responses. | vesicles comprised of the ether glycerolipids of the archaeon methanobrevibacter smithii (archaeosomes) are potent adjuvants for evoking cd8(+) t cell responses. we therefore explored the ability of archaeosomes to overcome immunologic tolerance to self-antigens. priming and boosting of mice with archaeosome-antigen evoked comparable cd8(+) t cell response and tumor protection to an alternate boosting strategy utilizing live bacterial vectors for antigen delivery. vaccination with melanoma antig ... | 2010 | 21318177 |
| archaea as emerging organisms in complex human microbiomes. | in this work, we review the state of knowledge of archaea associated with the human microbiome. these prokaryotes, initially discovered in extreme environments, were named archaea because these environments were thought to be the most primitive on earth. further research revealed that this terminology is misleading because these organisms were later found in various non-extreme environments, including the human host. further examination of the human microbiome has enabled the isolation of three ... | 2011 | 21420503 |
| structure modeling and inhibitor prediction ofnadp oxidoreductase enzyme from methanobrevibacter smithii. | the f420-dependent nadp oxidoreductase enzyme from methanobrevibacter smithii catalyzes the important electron transfer step during methanogenesis. therefore, it may act as potential target for blocking the process of methane formation. its protein sequence is available in genbank (accession number: abq86254.1) however no report has been found about its 3d protein structure. in this work, we first time claim 3d model structure of f420-dependent nadp oxidoreductase enzyme from methanobrevibacter ... | 2011 | 21464839 |
| terrestrial sources homogenize bacterial water quality during rainfall in two urbanized watersheds in santa barbara, ca. | microbiological contamination from runoff is a human health concern in urbanized coastal environments, but the contamination sources are often unknown. this study quantified fecal indicator bacteria and compared the distributions of human-specific genetic markers and bacterial community composition during dry and wet weather in urban creeks draining two neighboring watersheds in santa barbara, ca. in a prior study conducted during exclusively dry weather, the creeks were contaminated with human ... | 2011 | 21617896 |
| sewage exfiltration as a source of storm drain contamination during dry weather in urban watersheds. | separating storm drains and sanitary sewers is expected to control sewage pollution, for example from combined sewer overflows, and to reduce excessive stormwater flow to wastewater treatment plants. however, sewage contamination has been found in municipal separate storm drain systems in urban areas during dry weather flow. to determine if transmission of sewage is occurring from leaking sanitary sewers directly to leaking separated storm drains, field experiments were performed in three waters ... | 2011 | 21786744 |
| a 'universal' type ii chaperonin pcr detection system for the investigation of archaea in complex microbial communities. | bacteria and archaea are evolutionarily and biochemically distinct domains found together in many environments. robust 'universal' pcr primer sets targeting both the bacterial 16s rrna gene and the type i chaperonin gene have been established. however, 'universal' pcr primers for archaea are currently limited to the 16s rrna gene. we investigated the type ii chaperonin (known as the thermosome, tf55, cct or tcp-1) as a potential universal target (ut) for archaea. reproducible amplification of th ... | 2011 | 21776031 |
| the antimicrobial resistance pattern of cultured human methanogens reflects the unique phylogenetic position of archaea. | objectives methanogenic archaea are constant members of the human oral and digestive microbiota retrieved, in particular, from periodontitis lesions. the objective of the study was to determine their susceptibility to antimicrobials. methods using the macrodilution method in hungate tubes with optical microscope observation combined with monitoring methane production, we determined the antibiotic resistance characteristics of eight methanogenic archaea. results methanobrevibacter smithii strains ... | 2011 | 21680581 |
| obesity-associated gut microbiota is enriched in lactobacillus reuteri and depleted in bifidobacterium animalis and methanobrevibacter smithii. | background:obesity is associated with increased health risk and has been associated with alterations in bacterial gut microbiota, with mainly a reduction in bacteroidetes, but few data exist at the genus and species level. it has been reported that the lactobacillus and bifidobacterium genus representatives may have a critical role in weight regulation as an anti-obesity effect in experimental models and humans, or as a growth-promoter effect in agriculture depending on the strains.objectives an ... | 2011 | 21829158 |
| Relationship between rumen methanogens and methane production in dairy cows fed diets supplemented with a feed enzyme additive. | To investigate the relationship between ruminal methanogen community and host enteric methane (CH(4) ) production in lactating dairy cows fed diets supplemented with an exogenous fibrolytic enzyme additive. | 2011 | 21848695 |
| degradation of lignified secondary cell walls of lucerne (medicago sativa l.) by rumen fungi growing in methanogenic co-culture. | to compare the abilities of the monocentric rumen fungi neocallimastix frontalis, piromyces communis and caecomyces communis, growing in coculture with methanobrevibacter smithii, to colonize and degrade lignified secondary cell walls of lucerne (alfalfa) hay. | 2011 | 21848807 |
| Immunogenic properties of archaeal species found in bioaerosols. | The etiology of bioaerosol-related pulmonary diseases remains poorly understood. Recently, archaea emerged as prominent airborne components of agricultural environments, but the consequences of airway exposure to archaea remain unknown. Since subcomponents of archaea can be immunogenic, we used a murine model to study the pulmonary immune responses to two archaeal species found in agricultural facilities: Methanobrevibacter smithii (MBS) and Methanosphaera stadtmanae (MSS). Mice were administere ... | 2011 | 21858070 |
| Evaluation of the nifH Gene Marker of Methanobrevibacter smithii for the Detection of Sewage Pollution in Environmental Waters in Southeast Queensland, Australia. | This study aimed at evaluating the host-specificity and -sensitivity of the nifH gene marker of Methanobrevibacter smithii by screening 272 fecal and wastewater samples from 11 animal species including humans in Southeast Queensland (SEQ), Australia. In addition, environmental water samples (n=21) were collected during the dry and wet weather conditions and tested for the presence of the nifH marker along with other sewage-associated markers, namely, enterococci surface protein (esp) found in En ... | 2011 | 22070524 |
| culture-based indicators of fecal contamination and molecular microbial indicators rarely correlate with campylobacter spp. in recreational waters. | campylobacter spp. are the leading cause of gastroenteritis worldwide. most human infections result from contaminated food; however, infections are also caused by recreational waterway contamination. campylobacter culture is technically challenging and enumeration by culture-based methods is onerous. thus, we employed qpcr to quantify campylobacter spp. in fresh- and marine-water samples, raw sewage and animal feces. multiplex pcr determined whether campylobacter jejuni or c. coli, most commonly ... | 2011 | 22048429 |
| toxicity of methylated bismuth compounds produced by intestinal microorganisms to bacteroides thetaiotaomicron, a member of the physiological intestinal microbiota. | methanoarchaea have an outstanding capability to methylate numerous metal(loid)s therefore producing toxic and highly mobile derivatives. here, we report that the production of methylated bismuth species by the methanoarchaeum methanobrevibacter smithii, a common member of the human intestine, impairs the growth of members of the beneficial intestinal microbiota at low concentrations. the bacterium bacteroides thetaiotaomicron, which is of great importance for the welfare of the host due to its ... | 2011 | 21966291 |
| contribution of lateral gene transfer to the gene repertoire of a gut-adapted methanogen. | methanobrevibacter smithii is the most abundant archaeon in the human colon. as most of its neighbors are bacterial species, it is expected that lateral gene acquisition from bacteria might have contributed to the evolution and adaptation of this archaeon. we performed a tree-based genome-wide survey of putative lateral gene transfer products in m. smithii, using a phylogenetic pipeline. over 15% of the coding genes of m. smithii are inferred to be bacterial in origin, based on this analysis. la ... | 2012 | 22056789 |
| matrix-assisted laser desorption/ionization time-of-flight mass spectrometry identification of archaea: towards the universal identification of living organisms. | matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (maldi-tof-ms) identification of archaea has been limited to some environmental extremophiles belonging to distant taxa. we developed a specific protocol for maldi-tof-ms identification of archaea and applied it to seven environmental human-associated methanobrevibacter smithii, methanobrevibacter oralis, methanosphaera stadtmanae, and the recently described methanomassiliicoccus luminyensi archaea. after mechanical lys ... | 2011 | 22229263 |
| optimized microbial dna extraction from diarrheic stools. | the detection of enteropathogens in stool specimens increasingly relies on the detection of specific nucleic acid sequences. we observed that such detection was hampered in diarrheic stool specimens and we set-up an improved protocol combining lyophilization of stools prior to a semi-automated dna extraction. | 2012 | 23273000 |