Publications

acetogenesis from dichloromethane by a two-component mixed culture comprising a novel bacterium.	a strictly anaerobic two-component culture able to grow exponentially with a doubling time of 20 h on a medium containing dichloromethane as the carbon and energy source was characterized. on a medium without sulfate, we observed (per mol of dichloromethane) a mass balance of 2 mol of chloride, 0.26 mol of acetate, 0.05 mol of formate, and 0.25 mol of carbon in biomass. one component of the culture, strain dmb, was identified by a 16s ribosomal dna analysis as a desulfovibrio sp. the other compo ...	1995	16535097
phylogenetic analyses of some extremely halophilic archaea isolated from dead sea water, determined on the basis of their 16s rrna sequences.	twenty-two extremely halophilic aerobic archaeal strains were isolated from enrichments prepared from dead sea water samples collected 57 years ago. the isolates were phenotypically clustered into five different groups, and a representative from each group was chosen for further study. almost the entire sequences of the 16s rrna genes of these representatives, and of haloarcula hispanica atcc 33960, were determined to establish their phylogenetic positions. the sequences of these strains were co ...	1996	8837434
activation and degradation of benzoate, 3-phenylpropionate and crotonate by syntrophus buswellii strain ga. evidence for electron-transport phosphorylation during crotonate respiration.	a strictly anaerobic, benzoate-degrading bacterium, syntrophus buswellii strain ga, was able to degrade benzoate or 3-phenylpropionate to acetate, co2 and h2, if the hydrogen partial pressure was sufficiently low. the hydrogen was removed in syntrophic coculture by methanospirillum hungatei or by desulfovibrio sp. through interspecies hydrogen transfer or in pure culture by the use of crotonate as reducible cosubstrate. alternatively, s. buswellii strain ga could grow in pure culture with croton ...	1996	8867639
the response of selected members of the archaea to the gram stain.	archaea possess a broader range of cell envelope structural formats than eubacteria and their cell walls do not contain peptidoglycan. some archaea have only a single s-layer as their cell wall (e.g. methanococcus jannaschii and sulfolobus acidocaldarius), whereas others have multiple layers (e.g. methanospirillum hungatei). sometimes there can also be a high proportion of tetraether lipids in membranes to make the envelope more resilient to environmental stress (e.g. methanococcus jannaschii an ...	1996	8885405
formation of fatty acid-degrading, anaerobic granules by defined species.	an endospore-forming, butyrate-degrading bacterium (strain bh) was grown on butyrate in monoxenic coculture with a methanogen. the culture formed dense aggregates when methanobacterium formicicum was the methanogenic partner, but the culture was turbid when methanospirillum hungatei was the partner. in contrast, a propionate-degrading, lemon-shaped bacterium (strain pt) did not form aggregates with methanobacterium formicicum unless an acetate-degrading methanosaeta sp. was also included in the ...	1996	16535336
modeling and measuring the elastic properties of an archaeal surface, the sheath of methanospirillum hungatei, and the implication of methane production.	we describe a technique for probing the elastic properties of biological membranes by using an atomic force microscope (afm) tip to press the biological material into a groove in a solid surface. a simple model is developed to relate the applied force and observed depression distance to the elastic modulus of the material. a measurement on the proteinaceous sheath of the archaebacterium methanospirillum hungatei gp1 gave a young's modulus of 2 x 10(10) to 4 x 10(10) n/m2. the measurements sugges ...	1996	8655487
heat-shock response in methanosarcina mazei s-6.	the dnak locus of methanosarcina mazei s-6, a mesophilic organism of the phylogenetic domain archaea, contains the heat-shock genes 5'-grpe-dnak-dnaj-3'. parameters known to affect the response of these genes in organisms of the other two domains, bacteria and eucarya, were tested to determine their effects on the archaeal homologs. the mrna from the three genes increased after heat shock more in lamina than in single cells (these s-6 morphologic stages can be grown in the same substrate). singl ...	1997	9216886
anaerobic degradation of glycerol by desulfovibrio fructosovorans and d. carbinolicus and evidence for glycerol-dependent utilization of 1,2-propanediol	the degradation of glycerol by desulfovibrio carbinolicus and desulfovibrio fructosovorans was tested in pure culture with sulfate and in coculture with methanospirillum hungatei. desulfovibrio carbinolicus degraded glycerol into 3-hydroxypropionate with the formation of sulfide in pure culture and methane in the coculture. the maximum growth rates were 0.063 h-1 in pure culture and 0.014 h-1 in coculture (corresponding growth yields: 8.9 and 6.0 g dry weight/mol glycerol). with d. fructosovoran ...	1998	9541565
investigation of serine hydroxymethyltransferase in methanogens.	the cofactor specificity of serine hydroxymethyltransferase (shmt) activities was tested in extracts of several methanogens using tetrahydromethanopterin (h4mpt) from methanobacterium thermoautotrophicum marburg, tetrahydrosarcinapterin (h4spt) from methanosarcina barkeri, and tetrahydrofolate (h4folate) as the potential c1 carrier. in methanosphaera stadtmanae and methanococcus thermolithotrophicus, the activities were h4mpt dependent. in methanospirillum hungatei gp1, methanosaeta concilii, me ...	1998	9783425
syntrophobacter fumaroxidans sp. nov., a syntrophic propionate-degrading sulfate-reducing bacterium.	a syntrophic propionate-oxidizing bacterium, strain mpobt, was isolated from a culture enriched from anaerobic granular sludge. it oxidized propionate syntrophically in co-culture with the hydrogen- and formate-utilizing methanospirillum hungateii, and was able to oxidize propionate and other organic compounds in pure culture with sulfate or fumarate as the electron acceptor. additionally, it fermented fumarate. 16s rrna sequence analysis revealed a relationship with syntrophobacter wolinii and ...	1998	9828440
syntrophus aciditrophicus sp. nov., a new anaerobic bacterium that degrades fatty acids and benzoate in syntrophic association with hydrogen-using microorganisms.	strain sbt is a new, strictly anaerobic, gram-negative, nonmotile, non-sporeforming, rod-shaped bacterium that degrades benzoate and certain fatty acids in syntrophic association with hydrogen/formate-using microorganisms. strain sbt produced approximately 3 mol of acetate and 0.6 mol of methane per mol of benzoate in coculture with methanospirillum hungatei strain jf1. saturated fatty acids, some unsaturated fatty acids, and methyl esters of butyrate and hexanoate also supported growth of strai ...	1999	9914307
fluorescence in situ hybridization using 16s rrna-targeted oligonucleotides reveals localization of methanogens and selected uncultured bacteria in mesophilic and thermophilic sludge granules.	16s rrna-targeted in situ hybridization combined with confocal laser scanning microscopy was used to elucidate the spatial distribution of microbes within two types of methanogenic granular sludge, mesophilic (35 degrees c) and thermophilic (55 degrees c), in upflow anaerobic sludge blanket reactors fed with sucrose-, acetate-, and propionate-based artificial wastewater. the spatial organization of the microbes was visualized in thin sections of the granules by using fluorescent oligonucleotide ...	1999	10049894
culturable populations of sporomusa spp. and desulfovibrio spp. in the anoxic bulk soil of flooded rice microcosms.	most-probable-number (mpn) counts were made of homoacetogenic and other bacteria present in the anoxic flooded bulk soil of laboratory microcosms containing 90- to 95-day-old rice plants. mpn counts with substrates known to be useful for the selective enrichment or the cultivation of homoacetogenic bacteria (betaine, ethylene glycol, 2, 3-butanediol, and 3,4,5-trimethoxybenzoate) gave counts of 2.3 x 10(3) to 2.8 x 10(5) cells per g of dry soil. homoacetogens isolated from the terminal positive ...	1999	10427044
molecular characterization of a toluene-degrading methanogenic consortium.	a toluene-degrading methanogenic consortium enriched from creosote-contaminated aquifer material was maintained on toluene as the sole carbon and energy source for 10 years. the species in the consortium were characterized by using a molecular approach. total genomic dna was isolated, and 16s rrna genes were amplified by using pcr performed with kingdom-specific primers that were specific for 16s rrna genes from either members of the kingdom bacteria or members of the kingdom archaea. a total of ...	1999	10584020
characterization of the anaerobic propionate-degrading syntrophs smithella propionica gen. nov., sp. nov. and syntrophobacter wolinii.	a strain of anaerobic, syntrophic, propionate-oxidizing bacteria, strain lypt (= ocm 661t; t = type strain), was isolated and proposed as representative of a new genus and new species, smithella propionica gen. nov., sp. nov. the strain was enriched from an anaerobic digestor and isolated. initial isolation was as a monoxenic propionate-degrading co-culture containing methanospirillum hungateii jf-1t as an h2- and formate-using partner. later, an axenic culture was obtained by using crotonate as ...	1999	10319475
[use of the level of g+c n dna for studying the molecular phylogeny o f methanogenic archaebacteria].	a new method for theoretical analysis of the molecular phylogeny of bacteria, successfully applied earlier to nitrifying bacteria, was used to study the molecular phylogeny of methanogenic archaebacteria. the group studied included methanococcus igneus, methanococcus vannielii, methanothermus fervidus, methanolobus tindarius, methanobacterium formicicum, methanosarcina barkeri, methanobacterium thermoformicicum, methanoplanus limicola, methanospirillum hungatei, and methanobacterium thermoautotr ...	1999	10624685
desulfovirga adipica gen. nov., sp. nov., an adipate-degrading, gram-negative, sulfate-reducing bacterium.	a novel, mesophilic, gram-negative bacterium was isolated from an anaerobic digestor for municipal wastewater. the bacterium degraded adipate in the presence of sulfate, sulfite, thiosulfate and elemental sulfur. (e)-2-hexenedioate accumulated transiently in the degradation of adipate. (e)-2-hexenedioate, (e)-3-hexenedioate, pyruvate, lactate, c1-c12 straight-chain fatty acids and c2-c10 straight-chain primary alcohols were also utilized as electron donors. 3-phenylpropionate was oxidized to ben ...	2000	10758870
energetics of syntrophic propionate oxidation in defined batch and chemostat cocultures.	propionate consumption was studied in syntrophic batch and chemostat cocultures of syntrophobacter fumaroxidans and methanospirillum hungatei. the gibbs free energy available for the h(2)-consuming methanogens was <-20 kj mol of ch(4)(-1) and thus allowed the synthesis of 1/3 mol of atp per reaction. the gibbs free energy available for the propionate oxidizer, on the other hand, was usually >-10 kj mol of propionate(-1). nevertheless, the syntrophic coculture grew in the chemostat at steady-stat ...	2000	10877789
characterization of microbial consortia in a terephthalate-degrading anaerobic granular sludge system.	the microbial composition and spatial distribution in a terephthalate-degrading anaerobic granular sludge system were characterized using molecular techniques. 16s rdna clone library and sequence analysis revealed that 78.5% of 106 bacterial clones belonged to the delta subclass of the class proteobacteria; the remaining clones were assigned to the green non-sulfur bacteria (7.5%), synergistes (0.9%) and unidentified divisions (13.1%). most of the bacterial clones in the delta-proteobacteria for ...	2001	11158354
metabolism of benzoate, cyclohex-1-ene carboxylate, and cyclohexane carboxylate by "syntrophus aciditrophicus" strain sb in syntrophic association with h(2)-using microorganisms.	the metabolism of benzoate, cyclohex-1-ene carboxylate, and cyclohexane carboxylate by "syntrophus aciditrophicus" in cocultures with hydrogen-using microorganisms was studied. cyclohexane carboxylate, cyclohex-1-ene carboxylate, pimelate, and glutarate (or their coenzyme a [coa] derivatives) transiently accumulated during growth with benzoate. identification was based on comparison of retention times and mass spectra of trimethylsilyl derivatives to the retention times and mass spectra of authe ...	2001	11282627
pathway of propionate oxidation by a syntrophic culture of smithella propionica and methanospirillum hungatei.	the pathway of propionate conversion in a syntrophic coculture of smithella propionica and methanospirillum hungatei jf1 was investigated by (13)c-nmr spectroscopy. cocultures produced acetate and butyrate from propionate. [3-(13)c]propionate was converted to [2-(13)c]acetate, with no [1-(13)c]acetate formed. butyrate from [3-(13)c]propionate was labeled at the c2 and c4 positions in a ratio of about 1:1.5. double-labeled propionate (2,3-(13)c) yielded not only double-labeled acetate but also si ...	2001	11282636
microbial populations associated with treatment of an industrial dye effluent in an anaerobic baffled reactor.	fluorescent in situ hybridization (fish) using 16s and 23s rrna-targeted probes together with construction of an archaeal 16s ribosomal dna (rdna) clone library was used to characterize the microbial populations of an anaerobic baffled reactor successfully treating industrial dye waste. wastewater produced during the manufacture of food dyes containing several different azo and other dye compounds was decolorized and degraded under sulfidogenic and methanogenic conditions. use of molecular metho ...	2001	11425746
cluster structure of anaerobic aggregates of an expanded granular sludge bed reactor.	the metabolic properties and ultrastructure of mesophilic aggregates from a full-scale expanded granular sludge bed reactor treating brewery wastewater are described. the aggregates had a very high methanogenic activity on acetate (17.19 mmol of ch(4)/g of volatile suspended solids [vss].day or 1.1 g of ch(4) chemical oxygen demand/g of vss.day). fluorescent in situ hybridization using 16s rrna probes of crushed granules showed that 70 and 30% of the cells belonged to the archaebacterial and eub ...	2001	11472948
chemical structure of a novel aminophospholipid from hydrogenobacter thermophilus strain tk-6.	the phospholipid composition of hydrogenobacter thermophilus strain tk-6, an obligately chemolithoautotrophic, extremely thermophilic hydrogen bacterium, was analyzed. two of four phospholipids detected from the strain were assumed to be phosphatidylinositol and phosphatidylglycerol. an aminophospholipid named px, whose content among the phospholipids was 65%, was found to have a novel chemical structure by analysis of the dilyso form with nuclear magnetic resonance and fast atom bombardment-mas ...	2001	11591674
benzoate fermentation by the anaerobic bacterium syntrophus aciditrophicus in the absence of hydrogen-using microorganisms.	the anaerobic bacterium syntrophus aciditrophicus metabolized benzoate in pure culture in the absence of hydrogen-utilizing partners or terminal electron acceptors. the pure culture of s. aciditrophicus produced approximately 0.5 mol of cyclohexane carboxylate and 1.5 mol of acetate per mol of benzoate, while a coculture of s. aciditrophicus with the hydrogen-using methanogen methanospirillum hungatei produced 3 mol of acetate and 0.75 mol of methane per mol of benzoate. the growth yield of the ...	2001	11722901
propionate formation by opitutus terrae in pure culture and in mixed culture with a hydrogenotrophic methanogen and implications for carbon fluxes in anoxic rice paddy soil.	propionate-forming bacteria seem to be abundant in anoxic rice paddy soil, but biogeochemical investigations show that propionate is not a correspondingly important intermediate in carbon flux in this system. mixed cultures of opitutus terrae strain pb90-1, a representative propionate-producing bacterium from rice paddy soil, and the hydrogenotrophic methanospirillum hungatei strain sk maintained hydrogen partial pressures similar to those in the soil. the associated shift away from propionate f ...	2002	11916740
isolation and characterization of a motile hydrogenotrophic methanogen from rice paddy field soil in japan.	a hydrogenotrophic motile methanogen was isolated from flooded japanese paddy field soil. anaerobic incubation of the paddy soil on h(2)-co(2) at 20 degrees c led to the enrichment of symmetrically curved motile autofluorescent rods. the methanogenic strain tm20-1 isolated from the culture was halotolerant and utilized h(2)-co(2), 2-propanol-co(2), or formate as a sole methanogenic substrate. based on the 16s rrna gene sequence similarity (94.8%) with methanospirillum hungateii, and on the physi ...	2002	11959443
reduction of humic substances by halorespiring, sulphate-reducing and methanogenic microorganisms.	physiologically distinct anaerobic microorganisms were explored for their ability to oxidize different substrates with humic acids or the humic analogue, anthraquinone-2,6-disulphonate (aqds), as a terminal electron acceptor. most of the microorganisms evaluated including, for example, the halorespiring bacterium, desulfitobacterium pce1, the sulphate-reducing bacterium, desulfovibrio g11 and the methanogenic archaeon, methanospirillum hungatei jf1, could oxidize hydrogen linked to the reduction ...	2002	11966825
biochemical evidence for formate transfer in syntrophic propionate-oxidizing cocultures of syntrophobacter fumaroxidans and methanospirillum hungatei.	the hydrogenase and formate dehydrogenase levels in syntrophobacter fumaroxidans and methanospirillum hungatei were studied in syntrophic propionate-oxidizing cultures and compared to the levels in axenic cultures of both organisms. cells grown syntrophically were separated from each other by percoll gradient centrifugation. in s. fumaroxidans both formate dehydrogenase and hydrogenase levels were highest in cells which were grown syntrophically, while the formate-h(2) lyase activities were comp ...	2002	12200272
diversity and structure of the archaeal community in the leachate of a full-scale recirculating landfill as examined by direct 16s rrna gene sequence retrieval.	the diversity and structure of the archaeal community in the effluent leachate from a full-scale recirculating landfill was characterized by direct 16s rrna gene (16s rdna) retrieval. total-community dna was extracted from the microbial assemblages in the landfill leachate, and archaeal 16s rdnas were amplified with a universally conserved primer and an archaea-specific primer. the amplification product was then used to construct a 16s rdna clone library, and 70 randomly selected archaeal clones ...	2002	12351237
sporotomaculum syntrophicum sp. nov., a novel anaerobic, syntrophic benzoate-degrading bacterium isolated from methanogenic sludge treating wastewater from terephthalate manufacturing.	an anaerobic, mesophilic, syntrophic benzoate-degrading bacterium, designated strain fb(t), was isolated from methanogenic sludge which had been used to treat wastewater from the manufacture of terephthalic acid. cells were non-motile gram-positive rods that formed spores. the optimum temperature for growth was 35-40 degrees c, and the optimum ph was 7.0-7.2. a co-culture with the hydrogenotrophic methanogen methanospirillum hungatei converted benzoate to acetate, carbon dioxide, and methane. bu ...	2003	12605290
victivallis vadensis gen. nov., sp. nov., a sugar-fermenting anaerobe from human faeces.	a novel strictly anaerobic, cellobiose-degrading bacterium, strain cellot, was isolated from a human faecal sample by combining enrichments in liquid and soft-agar basal media. a noteworthy characteristic was its inability to grow on normal agar plates and in roll tubes. the cells were coccus shaped and non-motile, with an extracellular slime layer. growth of strain cellot occurred between 20 and 40degrees c, with optimal growth at 37 degrees c. the ph range for growth was 5-7.5 with an optimum ...	2003	12656175
two w-containing formate dehydrogenases (co2-reductases) involved in syntrophic propionate oxidation by syntrophobacter fumaroxidans.	two formate dehydrogenases (co2-reductases) (fdh-1 and fdh-2) were isolated from the syntrophic propionate-oxidizing bacterium syntrophobacter fumaroxidans. both enzymes were produced in axenic fumarate-grown cells as well as in cells which were grown syntrophically on propionate with methanospirillum hungatei as the h2 and formate scavenger. the purified enzymes exhibited extremely high formate-oxidation and co2-reduction rates, and low km values for formate. for the enzyme designated fdh-1, a ...	2003	12755703
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, ...	2003	14529955
identification and isolation of anaerobic, syntrophic phthalate isomer-degrading microbes from methanogenic sludges treating wastewater from terephthalate manufacturing.	the microbial populations responsible for anaerobic degradation of phthalate isomers were investigated by enrichment and isolation of those microbes from anaerobic sludge treating wastewater from the manufacturing of terephthalic acid. primary enrichments were made with each of three phthalate isomers (ortho-, iso-, and terephthalate) as the sole energy source at 37 degrees c with two sources of anaerobic sludge (both had been used to treat wastewater containing high concentrations of phthalate ...	2004	15006786
direct inhibition of methanogenesis by ferric iron.	observed inhibition of methanogenesis under fe(iii)-reducing conditions is usually explained by competition of methanogens and fe(iii)-reducing bacteria for the common substrates acetate and hydrogen. however, substrate competition alone cannot explain the strong inhibition of methanogenesis during fe(iii)-reduction. we demonstrate direct inhibition of methanogenesis by amorphous fe(oh)3 at concentrations between 0 and 10 mm in experiments with pure cultures of methanogens. the sensitivity towar ...	2004	19712419
the first true obligately syntrophic propionate-oxidizing bacterium, pelotomaculum schinkii sp. nov., co-cultured with methanospirillum hungatei, and emended description of the genus pelotomaculum.	a gram-positive, spore-forming, syntrophic propionate-oxidizing bacterium, pelotomaculum schinkii sp. nov. strain hh(t), was isolated as a co-culture with methanospirillum hungatei jf-1(t) from anaerobic, freeze-dried granular sludge obtained from an upflow anaerobic sludge bed reactor treating sugar beet wastewater. the bacterium converted propionate to acetate in co-culture with methanospirillum hungatei jf-1(t) or methanobacterium formicicum mf(nt), but not in co-culture with methanobrevibact ...	2005	16014504
evaluation of support matrices for immobilization of anaerobic consortia for efficient carbon cycling in waste regeneration.	efficient metabolism of fatty acids during anaerobic waste digestion requires development of consortia that include "fatty acid consuming h(2) producing bacteria" and methanogenic bacteria. the objective of this research was to optimize methanogenesis from fatty acids by evaluating a variety of support matrices for use in maintaining efficient syntrophic-methanogenic consortia. tested matrices included clays (montmorillonite and bentonite), glass beads (106 and 425-600mum), microcarriers (cytopo ...	2005	15649428
syntrophomonas erecta sp. nov., a novel anaerobe that syntrophically degrades short-chain fatty acids.	two novel anaerobes, strains gb4-38(t) and sb9-1, were isolated from an upflow anaerobic sludge blanket reactor for treating bean-curd farm wastewater and lotus field mud, respectively. the strains degraded straight-chain fatty acids with 4-8 carbon atoms in syntrophic association with methanogens and converted 1 mol butyrate into about 2 mol acetate and presumably 2 mol h(2). none of the branched-chain fatty acids tested could be degraded. benzoate was not degraded. fumarate, sulfate, thiosulfa ...	2005	15774665
microbial community in a geothermal aquifer associated with the subsurface of the great artesian basin, australia.	to investigate the biomass and phylogenetic diversity of the microbial community inhabiting the deep aquifer of the great artesian basin (gab), geothermal groundwater gushing out from the aquifer was sampled and analyzed. microbial cells in the groundwater were stained with acridine orange and directly counted by epifluorescence microscopy. microbial cells were present at a density of 10(8)-10(9) cells per liter of groundwater. archaeal and bacterial small-subunit rrna genes (rdnas) were amplifi ...	2005	15980939
pelotomaculum terephthalicum sp. nov. and pelotomaculum isophthalicum sp. nov.: two anaerobic bacteria that degrade phthalate isomers in syntrophic association with hydrogenotrophic methanogens.	an anaerobic phthalate isomer-degrading strain (jt(t)) that we previously isolated was characterized. in addition, a strictly anaerobic, mesophilic, syntrophic phthalate isomer-degrading bacterium, designated strain ji(t), was isolated and characterized in this study. both were non-motile rods that formed spores. in both strains, the optimal growth was observed at temperatures around 37 degrees c and neutral ph. in syntrophic co-culture with the hydrogenotrophic methanogen methanospirillum hunga ...	2006	16404568
microbial community of a mesophilic propionate-degrading methanogenic consortium in chemostat cultivation analyzed based on 16s rrna and acetate kinase genes.	we constructed a mesophilic anaerobic chemostat that was continuously fed with synthetic wastewater containing propionate as the sole source of carbon and energy. steady-state conditions were achieved below the critical dilution rate of 0.3 d (-1) with almost complete substrate degradation. the propionate-degrading methanogenic communities in the chemostat at dilution rates of 0.01, 0.08, and 0.3 d (-1) were analyzed using molecular biological techniques. fluorescence in situ hybridization with ...	2006	16496142
phenotypic properties and microbial diversity of methanogenic granules from a full-scale upflow anaerobic sludge bed reactor treating brewery wastewater.	methanogenic granules from an anaerobic bioreactor that treated wastewater of a beer brewery consisted of different morphological types of granules. in this study, the microbial compositions of the different granules were analyzed by molecular microbiological techniques: cloning, denaturing gradient gel electrophoresis and fluorescent in situ hybridization (fish), and scanning and transmission electron microscopy. we propose here that the different types of granules reflect the different stages ...	2006	16820491
distribution, structure and diversity of "bacterial" genes encoding two-component proteins in the euryarchaeota.	the publicly available annotated archaeal genome sequences (23 complete and three partial annotations, october 2005) were searched for the presence of potential two-component open reading frames (orfs) using gene category lists and blastp. a total of 489 potential two-component genes were identified from the gene category lists and blastp. two-component genes were found in 14 of the 21 euryarchaeal sequences (october 2005) and in neither the crenarchaeota nor the nanoarchaeota. a total of 20 pre ...	2006	16877318
microbial diversity of mesophilic methanogenic consortium that can degrade long-chain fatty acids in chemostat cultivation.	we established a chemostat cultivation method for a mesophilic methanogenic consortium that could degrade long-chain fatty acids (lcfa) using a completely stirred tank reactor (cstr) fed with synthetic wastewater containing oleic and palmitic acids as the carbon and energy sources. the critical dilution rate of the chemostat, in which most of the introduced lcfa were decomposed and mineralized, was 0.4 d(-1). the microbial community under steady-state condition at this dilution rate was analyzed ...	2006	17270719
pelotomaculum propionicicum sp. nov., an anaerobic, mesophilic, obligately syntrophic, propionate-oxidizing bacterium.	an anaerobic, mesophilic, syntrophic, propionate-oxidizing bacterium, strain mgp(t), was isolated as a defined co-culture with methanospirillum hungatei from the methanogenic sludge of a mesophilic upflow anaerobic sludge blanket (uasb) reactor. the strain grew in the presence of propionate, but only in co-culture with methanogens, suggesting that it is an obligately syntrophic bacterium. the optimum temperature for growth was 37 degrees c, and the optimum ph was between 6.5 and 7.2. based on co ...	2007	17625181
syntrophomonas palmitatica sp. nov., an anaerobic, syntrophic, long-chain fatty-acid-oxidizing bacterium isolated from methanogenic sludge.	a mesophilic, syntrophic, fatty-acid-oxidizing anaerobic strain, designated mpa(t), was isolated from granular sludge in a mesophilic upflow anaerobic sludge blanket reactor used to treat palm oil mill effluent. cells were slightly curved, non-motile rods. spore formation was not observed. the optimal temperature for growth was around 37 degrees c and optimal ph for growth was 7.0. strain mpa(t) was able to grow on crotonate or pentenoate plus butyrate in pure culture. in co-culture with the hyd ...	2007	17766887
identification and cultivation of anaerobic, syntrophic long-chain fatty acid-degrading microbes from mesophilic and thermophilic methanogenic sludges.	we investigated long-chain fatty acid (lcfa)-degrading anaerobic microbes by enrichment, isolation, and rna-based stable isotope probing (sip). primary enrichment cultures were made with each of four lcfa substrates (palmitate, stearate, oleate, or linoleate, as the sole energy source) at 55 degrees c or 37 degrees c with two sources of anaerobic granular sludge as the inoculum. after several transfers, we obtained seven stable enrichment cultures in which lcfas were converted to methane. the ba ...	2007	17189450
effect of dilution rate on the microbial structure of a mesophilic butyrate-degrading methanogenic community during continuous cultivation.	we constructed two mesophilic anaerobic chemostats that were continuously fed with synthetic wastewater containing butyrate as the sole source of carbon and energy. steady-state conditions were achieved at dilution rates between 0.025 and 0.7 day(-1). butyrate, fed into the chemostat, was almost completely mineralized to ch(4) and co(2) at dilution rates below 0.5 day(-1). the butyrate-degrading methanogenic communities in the chemostats at dilution rates between 0.025 and 0.7 day(-1) were monit ...	2007	17221191
effect of process temperature on bacterial and archaeal communities in two methanogenic bioreactors treating organic household waste.	the bacterial and archaeal community structure was examined in two methanogenic anaerobic digestion processes degrading organic household waste at mesophilic (37 degrees c) and thermophilic (55 degrees c) temperatures. analysis of bacterial clone libraries revealed a predominance of bacteroidetes (34% of total clones) and chloroflexi (27%) at the mesophilic temperature. in contrast, in the thermophilic clone library, the major group of clones were affiliated with thermotogae (61%). within the do ...	2007	17381521
development and assessment of whole-genome oligonucleotide microarrays to analyze an anaerobic microbial community and its responses to oxidative stress.	the application of dna microarray technology to investigate multiple-species microbial communities presents great challenges. in this study, we reported the design and quality assessment of four whole genome oligonucleotide microarrays for two syntroph bacteria, desulfovibrio vulgaris and syntrophobacter fumaroxidans, and two archaeal methanogens, methanosarcina barkeri, and methanospirillum hungatei, and their application to analyze global gene expression in a four-species microbial community i ...	2007	17498652
evaluation of methanogenic strains and their ability to endure aeration and water stress.	during periods of drainage, both water stress and oxygen can cause damage to indigenous methanogens. in the present study, we evaluated the tolerance of seven methanogenic strains (methanobrevibacter arboriphilicus, methanobacterium formicicum, methanococcus vannielii, methanospirillum hungatei, methanoculleus olentangyi, methanoplanus limicola, and methanosarcina mazei) to long-term exposure to air/nitrogen and drying. we found that these methanogenic strains except for m. limicola and m. olent ...	2008	17990030
characterization of the community structure of a dechlorinating mixed culture and comparisons of gene expression in planktonic and biofloc-associated "dehalococcoides" and methanospirillum species.	this study sought to characterize bacterial and archaeal populations in a perchloroethene- and butyrate-fed enrichment culture containing hydrogen-consuming "dehalococcoides ethenogenes" strain 195 and a methanospirillum hungatei strain. phylogenetic characterization of this microbial community was done via 16s rrna gene clone library and gradient gel electrophoresis analyses. fluorescence in situ hybridization was used to quantify populations of "dehalococcoides" and archaea and to examine the ...	2008	18776027
characterization of the archaeal community in a minerotrophic fen and terminal restriction fragment length polymorphism-directed isolation of a novel hydrogenotrophic methanogen.	minerotrophic fen peatlands are widely distributed in northern latitudes and, because of their rapid turnover of organic matter, are potentially larger sources of atmospheric methane than bog peatlands per unit area. however, studies of the archaeal community composition in fens are scarce particularly in minerotrophic sites. several 16s rrna-based primer sets were used to obtain a broad characterization of the archaeal community in a minerotrophic fen in central new york state. a wide archaeal ...	2008	18281434
methane production in an uasb reactor operated under periodic mesophilic-thermophilic conditions.	methane production was studied in a laboratory-scale 10 l anaerobic upflow sludge bed (uasb) reactor with periodic variations of the reactor temperature. on a daily basis the temperature was varied between 35 and 45 degrees c or 35 and 55 degrees c with a heating period of 6 h. each temperature increase was accompanied by an increase in methane production and a decrease in the concentration of soluble organic matter in the effluent. in comparison to a reactor operated at 35 degrees c, a net incr ...	2008	18383125
changes of microbial characteristics of retained sludge during low-temperature operation of an egsb reactor for low-strength wastewater treatment.	in this study, a lab scale egsb reactor was operated for 400 days to investigate the influence of temperature-decrease on the microbial characteristic of retained sludge. the egsb reactor was started-up at 15 degrees c seeding with 20 degrees c-grown granular sludge. the influent cod of synthetic wastewater was set at 0.6-0.8 gcod/l. the process-temperature was stepwise reduced from 15 degrees c to 5 degrees c during 400 days operation. decrease of temperature of the reactor from 15 degrees c to ...	2008	18235183
changes in process performance and microbial characteristics of retained sludge during low-temperature operation of an egsb reactor.	a lab-scale expanded granular sludge bed (egsb) reactor was seeded with granular sludge and operated to investigate the influence of temperature decrease on both process performance and the microbial community structure of the granular sludge. synthetic wastewater containing sucrose and volatile fatty acids was used as feed. the egsb reactor was brought online at a starting temperature of 15 degrees c and was reduced stepwise to a final temperature of 5 degrees c. the reactor exhibited sufficien ...	2008	18988102
[microbial community in granules from an egsb reactor operated at 20 degrees c].	the microbial communities in 6 granular sludge samples taken from a lab-scale egsb reactor operated under different organic loading rates (olr) at 20 degrees c were studied using pcr-dgge and rtq-pcr technique. the results indicate that as the olr increased from 1.5 kg/(m3 x d) to 10.0 kg/(m3 x d), the microbial communities of archaea and eubacteria in the 6 sludge samples are not changed greatly. the archaea population is highly similar among the 6 samples. the shannon indexes of archaea popula ...	2008	19068643
analysis of microbial community during biofilm development in an anaerobic wastewater treatment reactor.	the formation, structure, and biodiversity of a multispecies anaerobic biofilm inside an upflow anaerobic sludge bed (uasb) reactor fed with brewery wastewater was examined using complementary microbial ecology methods such us fluorescence in situ hybridization (fish), denaturing gradient gel electrophoresis (dgge), and cloning. the biofilm development can be roughly divided into three stages: an initial attachment phase (0-36 h) characterized by random adhesion of the cells to the surface; a co ...	2008	18034358
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
transcriptional responses to biologically relevant doses of uv-b radiation in the model archaeon, halobacterium sp. nrc-1.	most studies of the transcriptional response to uv radiation in living cells have used uv doses that are much higher than those encountered in the natural environment, and most focus on short-wave uv (uv-c) at 254 nm, a wavelength that never reaches the earth's surface. we have studied the transcriptional response of the sunlight-tolerant model archaeon, halobacterium sp. nrc-1, to low doses of mid-wave uv (uv-b) to assess its response to uv radiation that is likely to be more biologically relev ...	2008	18759987
dominant sugar utilizers in sediment of lake constance depend on syntrophic cooperation with methanogenic partner organisms.	six strains of novel bacteria were isolated from profundal sediment of lake constance, a deep freshwater lake in germany, by direct dilution of the sediment in mineral agar medium containing a background lawn of the hydrogen-scavenging methanospirillum hungatei as a syntrophic partner. the numbers of colony-forming units obtained after incubation for more than 2 months were in the same range as those of total bacterial counts determined by dapi staining (up to 10(8) cells per millilitre) suggest ...	2008	18248451
reactor performance and microbial community of an egsb reactor operated at 20 and 15 degrees c.	to investigate the effects of low temperatures on the performance and microbial community of anaerobic wastewater treatment.	2009	19320945
involvement of nadh:acceptor oxidoreductase and butyryl coenzyme a dehydrogenase in reversed electron transport during syntrophic butyrate oxidation by syntrophomonas wolfei.	methanogenic oxidation of butyrate to acetate requires a tight cooperation between the syntrophically fermenting syntrophomonas wolfei and the methanogen methanospirillum hungatei, and a reversed electron transport system in s. wolfei was postulated to shift electrons from butyryl coenzyme a (butyryl-coa) oxidation to the redox potential of nadh for h(2) generation. the metabolic activity of butyrate-oxidizing s. wolfei cells was measured via production of formazan and acetate from butyrate, wit ...	2009	19648244
metabolism of hydroxylated and fluorinated benzoates by syntrophus aciditrophicus and detection of a fluorodiene metabolite.	transformations of 2-hydroxybenzoate and fluorobenzoate isomers were investigated in the strictly anaerobic syntrophus aciditrophicus to gain insight into the initial steps of the metabolism of aromatic acids. 2-hydroxybenzoate was metabolized to methane and acetate by s. aciditrophicus and methanospirillum hungatei cocultures and reduced to cyclohexane carboxylate by pure cultures of s. aciditrophicus when grown in the presence of crotonate. under both conditions, transient accumulation of benz ...	2009	19114508
the structure of the bacterial and archaeal community in a biogas digester as revealed by denaturing gradient gel electrophoresis and 16s rdna sequencing analysis.	to identify the bacterial and archaeal composition in a mesophilic biogas digester treating pig manure and to compare the consistency of two 16s rdna-based methods to investigate the microbial structure.	2009	19187154
genomic characterization of methanomicrobiales reveals three classes of methanogens.	methanomicrobiales is the least studied order of methanogens. while these organisms appear to be more closely related to the methanosarcinales in ribosomal-based phylogenetic analyses, they are metabolically more similar to class i methanogens.	2009	19495416
effect of tungsten and molybdenum on growth of a syntrophic coculture of syntrophobacter fumaroxidans and methanospirillum hungatei.	the effect of tungsten (w) and molybdenum (mo) on the growth of syntrophobacter fumaroxidans and methanospirillum hungatei was studied in syntrophic cultures and the pure cultures of both the organisms. cells that were grown syntropically were separated by percoll density centrifugation. measurement of hydrogenase and formate dehydrogenase levels in cell extracts of syntrophically grown cells correlated with the methane formation rates in the co-cultures. the effect of w and mo on the activity o ...	2009	18795263
methanospirillum lacunae sp. nov., a methane-producing archaeon isolated from a puddly soil, and emended descriptions of the genus methanospirillum and methanospirillum hungatei.	a mesophilic, hydrogenotrophic methanogen, designated strain ki8-1(t), was isolated from soil. cells were strictly anaerobic, gram-stain-negative, non-sporulating, motile by means of a single flagellum or tufted flagella, and curved or wavy rod-shaped (11-25 μm long). the temperature and ph for optimum growth were 30 °c and 7.5. the strain grew best in basal medium without the addition of nacl. methane was produced from h(2) and formate. acetate or yeast extract was required for growth. the g+c ...	2010	20008107
microbial community structure and population dynamics of granules developed in expanded granular sludge bed (egsb) reactors for the anaerobic treatment of low-strength wastewater at low temperature.	the anaerobic biological treatment of sucrose-based, low-strength wastewater was investigated in expanded granular sludge bed (egsb) reactors at low temperatures over a 300-day trial period. during the trial, the operating temperature was lowered in a stepwise manner from 20 degrees c to 5 degrees c. as a result, the reactors exhibited sufficient performances until 10 degrees c operation. the cod removal rate was 3.1-3.8 kgcod m(-3) day(-1) at 10 degrees c. in particular, the cod removal rate in ...	2010	20390923
growth- and substrate-dependent transcription of formate dehydrogenase and hydrogenase coding genes in syntrophobacter fumaroxidans and methanospirillum hungatei.	transcription of genes coding for formate dehydrogenases (fdh genes) and hydrogenases (hyd genes) in syntrophobacter fumaroxidans and methanospirillum hungatei was studied following growth under different conditions. under all conditions tested, all fdh and hyd genes were transcribed. however, transcription levels of the individual genes varied depending on the substrate and growth conditions. our results strongly suggest that in syntrophically grown s. fumaroxidans cells, the [fefe]-hydrogenase ...	2010	20884694
microbial dynamics in upflow anaerobic sludge blanket (uasb) bioreactor granules in response to short-term changes in substrate feed.	the upflow anaerobic sludge blanket (uasb) reactor is a microcosm for the methanogenic degradation of organic matter in anaerobic environments, and depends on the auto-formation of dense 3d biofilms of 1-3 mm in diameter, referred to as granular sludge (biogranules). past research has shown that uasb and other methanogenic reactors are extremely stable functionally, but the underlying basis of the functional stability is not well understood. in this study, microbial dynamics in the communities r ...	2010	20430810
effects of hydrogen and acetate on benzene mineralisation under sulphate-reducing conditions.	syntrophic mineralisation of benzene, as recently proposed for a sulphate-reducing enrichment culture, was tested in product inhibition experiments with acetate and hydrogen, both putative intermediates of anaerobic benzene fermentation. using [(13)c(6)]-benzene enabled tracking the inhibition of benzene mineralisation sensitively by analysis of (13)co(2). in noninhibited cultures, hydrogen was detected at partial pressures of 2.4 × 10(-6) ± 1.5 × 10(-6) atm. acetate was detected at concentratio ...	2011	21449939
metabolism of h2 by desulfovibrio desulfuricans g20 during syntrophic growth on lactate.	syntrophic growth involves the oxidation of organic compounds and subsequent transfer of electrons to a h2- or formate-consuming microorganism. in order to identify genes specifically involved in syntrophic growth, a mutant library of desulfovibrio desulfuricans g20 was screened for loss of the ability to grow syntrophically with methanospirillum hungatei. a collection of twenty mutants with an impaired ability to grow syntrophically was obtained. all twenty mutants grew in pure culture on lacta ...	2011	21798981
structural, mass and elemental analyses of storage granules in methanogenic archaeal cells.	storage granules are an important component of metabolism in many organisms spanning the bacterial, eukaryal and archaeal domains, but systematic analysis of their organization inside cells is lacking. in this study, we identify and characterize granule-like inclusion bodies in a methanogenic archaeon, methanospirillum hungatei, an anaerobic microorganism that plays an important role in nutrient recycling in the ecosystem. using cryo electron microscopy, we show that granules in mature m. hungat ...	2011	21854518
methanogen community structure-activity relationship and bioaugmentation of overloaded anaerobic digesters.	accumulation of acids in anaerobic digesters after organic overload can inhibit or stop ch4 production. therefore, methods to reduce acid concentrations would be helpful. one potential method to improve recovery involves bioaugmentation, addition of specific microorganisms to improve performance. in this study, transiently overloaded digesters were bioaugmented with a propionate-degrading enrichment culture in an effort to decrease recovery time. biomass samples from 14 different, full-scale ana ...	2011	21855955
Archaeal community composition affects the function of anaerobic co-digesters in response to organic overload.	Microbial community diversity in two thermophilic laboratory-scale and three full-scale anaerobic co-digesters was analysed by genetic profiling based on PCR-amplified partial 16S rRNA genes. In parallel operated laboratory reactors a stepwise increase of the organic loading rate (OLR) resulted in a decrease of methane production and an accumulation of volatile fatty acids (VFAs). However, almost threefold different OLRs were necessary to inhibit the gas production in the reactors. During stable ...	2011	22192420
transcription of fdh and hyd in syntrophobacter spp. and methanospirillum spp. as a diagnostic tool for monitoring anaerobic sludge deprived of molybdenum, tungsten and selenium.	formate dehydrogenases and hydrogenases contain molybdenum or tungsten and/or selenium. these enzymes are crucial for interspecies formate and hydrogen transfer between propionate degrading syntrophobacter spp. and methanogenic methanospirillum spp. here we used reverse transcription of total rna followed by quantitative pcr (rt-qpcr) with specific primers to get insight into interspecies formate and hydrogen transfer. transcriptional regulation of formate dehydrogenases and hydrogenases in synt ...	2011	21332622