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Dennis G Sprott - One of the best experts on this subject based on the ideXlab platform.
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Methanosaeta concilii gen nov sp nov methanothrix concilii and Methanosaeta thermoacetophila nom rev comb nov
International Journal of Systematic and Evolutionary Microbiology, 1990Co-Authors: Girishchandra B. Patel, Dennis G SprottAbstract:Methanosaeta concilii gen. nov., sp. nov. (“Methanothrix concilii”) is described. Cells of species in the genus Methanosaeta are obligately anaerobic, gram-negative, nonmotile rods (length, 2.5 to 6.0 μm) with flat ends. The cells are enclosed within a proteinaceous, cross-striated sheath. Growth can occur as long filaments which represent chains of individual cells separated by spacer plugs and continuously enclosed by the tubular sheath. Acetic acid is used as the sole source of energy; its metabolism results in the production of about equimolar amounts of CH4 and CO2. Acetic acid and CO2 are carbon sources for growth. The description of Methanosaeta concilii, the type species, is based on type strain GP6 (= DSM 3671 = OGC 69 = NRC 2989 = ATCC 35969).
Seokhwan Hwang - One of the best experts on this subject based on the ideXlab platform.
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Temporal variation in bacterial and methanogenic communities of three full-scale anaerobic digesters treating swine wastewater
Environmental Science and Pollution Research, 2019Co-Authors: Seung Gu Shin, Seokhwan HwangAbstract:To investigate the effects of temporal variations of process parameters on microbial community structures in the two types of full-scale anaerobic digester treating swine wastewater, three full-scale anaerobic digesters were monitored. An anaerobic filter (AF)-type digester located in Gong-Ju (GJ) showed the highest COD removal among three digesters and maintained stable efficiency. A digester in Hong-Seong (HS) was of the same type as it GJ and showed improved efficiency over the sampling period. A continuously stirred tank reactor (CSTR)-type digester in Soon-Cheon (SC) showed decreasing efficiency due to a high residual concentration of VFAs and NH_4^+. These process efficiencies were closely correlated to the Simpson indices of the methanogenic communities. Genera Bacillus , Methanosaeta , and Methanospirillum that have filamentous morphology were dominant in both AF-type digesters, but genera Acholeplasma , Methanosarcina , and Methanoculleus that have spherical or coccoid morphology were dominantly abundant in the CSTR-type digester. Correlation between populations suggests a possible syntrophic relationship between genera Desulfobulbus and Methanosaeta in digesters GJ and HS.
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Temporal variation in methanogen communities of four different full-scale anaerobic digesters treating food waste-recycling wastewater.
Bioresource Technology, 2014Co-Authors: Byungchul Hwang, Seung Gu Shin, Seokhwan HwangAbstract:Methanogen communities were investigated using 454 pyrosequencing in four different full-scale anaerobic digesters treating food waste-recycling wastewater. Seasonal samples were collected for 2 years, and 24 samples were available for microbial analysis from a plug flow thermophilic (PT) digester, a continuously-stirred tank thermophilic (CT) digester, an upflow anerobic sludge blanket mesophilic (UM) digester, and a continuously-stirred tank mesophilic (CM) digester. Methanoculleus, Methanobacterium, Methanothermobacter, and Methanosaeta were revealed to be key methanogens in full-scale anaerobic digestion process treating food waste-recycling wastewater. In the PT digester, Methanoculleus was dominant (96.8%). In the CT digester, Methanoculleus was dominant (95.4%) during the first year of operation, but the dominant genus was shifted to Methanothermobacter (98.5%) due to pH increase. In the UM digester, Methanosaeta was dominant (87.2%). In the CM digester, Methanoculleus was constantly dominant (74.8%) except during CM5 when Methanosaeta was dominant (62.6%) due to the low residual acetate concentration (0.1 g/L).
Girishchandra B. Patel - One of the best experts on this subject based on the ideXlab platform.
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A contrary view of the proposal to assign a neotype strain for Methanothrix soehngenii.
International Journal of Systematic Bacteriology, 1992Co-Authors: Girishchandra B. PatelAbstract:Arguments are presented for the rejection of the proposal (D. R. Boone, Int. J. Syst. Bacteriol. 41:588-589, 1991) that the type strain GP6 of Methanosaeta concilii be designated as the neotype strain of Methanothrix soehngenii.
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Methanosaeta concilii gen. nov. sp. nov. ("Methanothrix concilii") and Methanosaeta thermoacetophila nom. rev., comb. nov.?
International Journal of Systematic Bacteriology, 1990Co-Authors: Girishchandra B. Patel, G. Dennis SprottAbstract:Methanosaeta concilii gen. nov., sp. nov. (“Methanothrix concilii”) is described. Cells of species in the genus Methanosaeta are obligately anaerobic, gram-negative, nonmotile rods (length, 2.5 to 6.0 μm) with flat ends. The cells are enclosed within a proteinaceous, cross-striated sheath. Growth can occur as long filaments which represent chains of individual cells separated by spacer plugs and continuously enclosed by the tubular sheath. Acetic acid is used as the sole source of energy; its metabolism results in the production of about equimolar amounts of CH4 and CO2. Acetic acid and CO2 are carbon sources for growth. The description of Methanosaeta concilii, the type species, is based on type strain GP6 (= DSM 3671 = OGC 69 = NRC 2989 = ATCC 35969).
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Methanosaeta concilii gen nov sp nov methanothrix concilii and Methanosaeta thermoacetophila nom rev comb nov
International Journal of Systematic and Evolutionary Microbiology, 1990Co-Authors: Girishchandra B. Patel, Dennis G SprottAbstract:Methanosaeta concilii gen. nov., sp. nov. (“Methanothrix concilii”) is described. Cells of species in the genus Methanosaeta are obligately anaerobic, gram-negative, nonmotile rods (length, 2.5 to 6.0 μm) with flat ends. The cells are enclosed within a proteinaceous, cross-striated sheath. Growth can occur as long filaments which represent chains of individual cells separated by spacer plugs and continuously enclosed by the tubular sheath. Acetic acid is used as the sole source of energy; its metabolism results in the production of about equimolar amounts of CH4 and CO2. Acetic acid and CO2 are carbon sources for growth. The description of Methanosaeta concilii, the type species, is based on type strain GP6 (= DSM 3671 = OGC 69 = NRC 2989 = ATCC 35969).
Rasmus Jakobsen - One of the best experts on this subject based on the ideXlab platform.
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Methanosarcina spp. drive vinyl chloride dechlorination via interspecies hydrogen transfer.
Applied and Environmental Microbiology, 2006Co-Authors: Axel Colin Heimann, Damien John Batstone, Rasmus JakobsenAbstract:Two highly enriched cultures containing Dehalococcoides spp. were used to study the effect of aceticlastic methanogens on reductive vinyl chloride (VC) dechlorination. In terms of aceticlastic methanogens, one culture was dominated by Methanosaeta, while the other culture was dominated by Methanosarcina, as determined by fluorescence in situ hybridization. Cultures amended with 2-bromoethanesulfonate (BES), an efficient inhibitor of methanogens, exhibited slow VC dechlorination when grown on acetate and VC. Methanogenic cultures dominated by Methanosaeta had no impact on dechlorination rates, compared to BES-amended controls. In contrast, methanogenic cultures dominated by Methanosarcina displayed up to sevenfold-higher rates of VC dechlorination than their BES-amended counterparts. Methanosarcina-dominated cultures converted a higher percentage of [2-14C]acetate to 14CO2 when concomitant VC dechlorination took place, compared to nondechlorinating controls. Respiratory indices increased from 0.12 in nondechlorinating cultures to 0.51 in actively dechlorinating cultures. During VC dechlorination, aqueous hydrogen (H2) concentrations dropped to 0.3 to 0.5 nM. However, upon complete VC consumption, H2 levels increased by a factor of 10 to 100, indicating active hydrogen production from acetate oxidation. This process was thermodynamically favorable by means of the extremely low H2 levels during dechlorination. VC degradation in nonmethanogenic cultures was not inhibited by BES but was limited by the availability of H2 as electron donor, in cultures both with and without BES. These findings all indicate that Methanosarcina (but not Methanosaeta), while cleaving acetate to methane, simultaneously oxidizes acetate to CO2 plus H2, driving hydrogenotrophic dehalorespiration of VC to ethene by Dehalococcoides.
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Methanosarcina spp. drive vinyl chloride dechlorination via interspecies hydrogen transfer.
Applied and Environmental Microbiology, 2006Co-Authors: Axel Colin Heimann, Damien John Batstone, Rasmus JakobsenAbstract:Two highly enriched cultures containing Dehalococcoides spp. were used to study the effect of aceticlastic methanogens on reductive vinyl chloride (VC) dechlorination. In terms of aceticlastic methanogens, one culture was dominated by Methanosaeta, while the other culture was dominated by Methanosarcina, as determined by fluorescence in situ hybridization. Cultures amended with 2-bromoethanesulfonate (BES), an efficient inhibitor of methanogens, exhibited slow VC dechlorination when grown on acetate and VC. Methanogenic cultures dominated by Methanosaeta had no impact on dechlorination rates, compared to BES-amended controls. In contrast, methanogenic cultures dominated by Methanosarcina displayed up to sevenfold-higher rates of VC dechlorination than their BES-amended counterparts. Methanosarcina-dominated cultures converted a higher percentage of [2-14C]acetate to 14CO2 when concomitant VC dechlorination took place, compared to nondechlorinating controls. Respiratory indices increased from 0.12 in nondechlorinating cultures to 0.51 in actively dechlorinating cultures. During VC dechlorination, aqueous hydrogen (H2) concentrations dropped to 0.3 to 0.5 nM. However, upon complete VC consumption, H2 levels increased by a factor of 10 to 100, indicating active hydrogen production from acetate oxidation. This process was thermodynamically favorable by means of the extremely low H2 levels during dechlorination. VC degradation in nonmethanogenic cultures was not inhibited by BES but was limited by the availability of H2 as electron donor, in cultures both with and without BES. These findings all indicate that Methanosarcina (but not Methanosaeta), while cleaving acetate to methane, simultaneously oxidizes acetate to CO2 plus H2, driving hydrogenotrophic dehalorespiration of VC to ethene by Dehalococcoides.
Yoichi Kamagata - One of the best experts on this subject based on the ideXlab platform.
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Aceticlastic and NaCl-requiring methanogen "Methanosaeta pelagica" sp. nov., isolated from marine tidal flat sediment.
Applied and Environmental Microbiology, 2012Co-Authors: Koji Mori, Takao Iino, Ken-ichiro Suzuki, Kaoru Yamaguchi, Yoichi KamagataAbstract:ABSTRACT Among methanogens, only 2 genera, Methanosaeta and Methanosarcina, are known to contribute to methanogenesis from acetate, and Methanosaeta is a specialist that uses acetate specifically. However, Methanosaeta strains so far have mainly been isolated from anaerobic digesters, despite the fact that it is widespread, not only in anaerobic methanogenic reactors and freshwater environments, but also in marine environments, based upon extensive 16S rRNA gene-cloning analyses. In this study, we isolated an aceticlastic methanogen, designated strain 03d30q T , from a tidal flat sediment. Phylogenetic analyses based on 16S rRNA and mcrA genes revealed that the isolate belongs to the genus Methanosaeta. Unlike the other known Methanosaeta species, this isolate grows at Na + concentrations of 0.20 to 0.80 M, with an optimum concentration of 0.28 M. Quantitative estimation using real-time PCR detected the 16S rRNA gene of the genus Methanosaeta in the marine sediment, and relative abundance ranged from 3.9% to 11.8% of the total archaeal 16S rRNA genes. In addition, the number of Methanosaeta organisms increased with increasing depth and was much higher than that of Methanosarcina organisms, suggesting that aceticlastic methanogens contribute to acetate metabolism to a greater extent than previously thought in marine environments, where sulfate-reducing acetate oxidation prevails. This is the first report on marine Methanosaeta species, and based on phylogenetic and characteristic studies, the name “Methanosaeta pelagica” sp. nov. is proposed for this novel species, with type strain 03d30q.
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Rejection of the species Methanothrix soehngeniiVPand the genus MethanothrixVPas nomina confusa, and transfer of Methanothrix thermophilaVPto the genus MethanosaetaVPas Methanosaeta thermophila comb. nov. Request for an Opinion
International Journal of Systematic Bacteriology, 1998Co-Authors: David R. Boone, Yoichi KamagataAbstract:We request an Opinion of the Judicial Commission regarding rejection of the species Methanothrix soehngenii VPHuser, Wuhrmann and Zehnder 1983, 439, and the genus Methanothrix VPHuser, Wuhrmann and Zehnder 1983, 439, as nomina confusa because their descriptions were based on the characterization of an impure type strain, strain OpfikonT. We also propose the transfer of Methanothrix thermophila VPKamagata et al. 1992, 465, to the genus Methanosaeta as Methanosaeta thermophila comb. nov.
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Characterization of three thermophilic strains of Methanothrix ("Methanosaeta") thermophila sp. nov. and rejection of Methanothrix ("Methanosaeta") thermoacetophila.
International Journal of Systematic Bacteriology, 1992Co-Authors: Yoichi Kamagata, Hiroshi Oyaizu, Eiichi Mikami, Hiroko Kawasaki, Kazunori Nakamura, Ginro Endo, Yosuke Koga, Kazuhide YamasatoAbstract:Three thermophilic Methanothrix (“Methanosaeta”) strains, strains PT T (= DSM 6194T) (T = type strain), CALS-1 (= DSM 3870), and Z-517 (= DSM 4774), were characterized chemotaxonomically and compared with five mesophilic strains, Methanothrix soehngenii (“Methanosaeta concilii”) GP6 (= DSM 3671), Opfikon (= DSM 2139), FE (= DSM 3013), UA, and PM. These methanogens were exclusively acetotrophic and had a characteristic sheathed structure. The DNA base compositions of the strains which we studied ranged from 50.3 to 54.3 mol% guanine plus cytosine. The thermophilic strains often had phase-refractive gas vesicles inside their cells. Denaturing electrophoresis of proteins showed that the mesophilic and thermophilic Methanothrix strains formed two distinct groups and that there were differences in protein patterns between the groups. The difference between the thermophiles and mesophiles was also verified by comparing partial 16S rRNA sequences (ca. 30 base differences in ca. 540 bases). On the basis of our results, we propose the name Methanothrix thermophila for the three thermophilic strains. The type strain of M. thermophila is strain PT (= DSM 6194). We also propose that the name Methanothrix thermoacetophila (“Methanosaeta thermoacetophila”), which was given to strain Z-517 (type strain), should be rejected because of its description, which was based on an enrichment culture, was inadequate.
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Isolation and Characterization of a Novel Thermophilic Methanosaeta Strain
International Journal of Systematic Bacteriology, 1991Co-Authors: Yoichi Kamagata, Eiichi MikamiAbstract:A novel thermophilic acetotrophic Methanosaeta strain was isolated from a thermophilic anaerobic digest or by using acetate enrichment and serial dilution in the presence of vancomycin and neomycin. This isolate, designated Methanosaeta sp. strain PT, resembled Methanosaeta sp. strain CALS-1 morphologically; however, it occasionally formed filaments longer than 100 μm and exhibited autofluorescence. The content of coenzyme F420 was much higher than that of Methanosaeta reference strains, and coenzyme F420 with four glutamyl residues on the side chain was the predominant component. Furthermore, a comparative analysis of the antigenic fingerprint of strain PT with the fingerprints of reference organisms showed that this isolate was not related antigenically to the reference methanogens, including Methanosaeta sp. (“Methanothrix” sp.) strain CALS-1 and Methanosaeta concilii (“Methanothrix soehngenii”) Opfikon. Strain PT formed visible colonies in a deep agar medium when high cell concentrations were present. However, transfer of a colony into liquid medium resulted in no growth. Strain PT could utilize only acetate as a sole carbon and energy source. The optimum temperature and optimum pH for methanogenesis were near 55°C and 6.7, respectively. The specific methane formation rate μCH 4 under optimum conditions was 0.47 day−1, and the doubling time was 1.49 days. The DNA base composition was 52.7 mol% guanine plus cytosine.