Methanobacterium paludis sp. nov. and a novel strain of Methanobacterium lacus isolated from northern peatlands

Abstract

The strains used H 2 /CO 2 but not formate or other substrates for methanogenesis, grew optimally around 32-37 6C, and their growth spanned through a slightly low to neutral pH range (4.7-7.1). Strain AL-21 grew optimally closer to neutrality at pH 6.2, whereas strain SWAN1 T showed a lower optimal pH at 5.4-5.7. The two strains were sensitive to NaCl with a maximal tolerance at 160 mM for strain SWAN1 T and 50 mM for strain AL-21. Na 2 S was toxic at very low concentrations (0.01-0.8 mM), resulting in growth inhibition above these values. The DNA G+C content of the genomes was 35.7 mol% for strain SWAN1 T and 35.8 mol% for strain AL-21.Phylogenetic analysis of the 16S rRNA gene sequences showed that the strains are members of the genus Methanobacterium. Strain SWAN1 T shared 94-97 % similarity with the type strains of recognized species of the genus Methanobacterium, whereas strain AL-21 shared 99 % similarity with Methanobacterium lacus 17A1 T . On the basis of phenotypic, genomic and phylogenetic

The genome of an endosymbiotic methanogen is very similar to those of its free‐living relatives

“…Phylogenetic and phylogenomic analysis of Methanobacterium species demonstrated that the CSS M. sp. clustered with clones from an acidic peat bog, M. lacus strains isolated from peat moss (Cadillo‐Quiroz et al ., ) and lake sediments (Borrel et al ., ) and M. sp. SMA‐27, which was isolated from permafrost (Fig.…”

Control of Sulfide Production in High Salinity Bakken Shale Oil Reservoirs by Halophilic Bacteria Reducing Nitrate to Nitrite

“…Community compositions of SW-IW samples were dominated by microorganisms, which grow optimally at moderate salinities (Table 2, Table S2) such as Methanolobus (optimum 0.35 M NaCl; Michimaru et al, 2009), Thiomicrospira (optimum 0.47 M NaCl; Brinkhoff and Kuever, 1999), Desulfovibrio (optimum 1.0 M NaCl for halophilic Desulfovibrio ; Tardy-Jacquenod et al, 1998), Methanobacterium (optimum 0.1 M NaCl with tolerance of up to 1.7 M NaCl for some strains; Cadillo-Quiroz et al, 2014) and Pelobacter (minimally 0.2 M NaCl; Nasaringarao and Häggblom, 2007). Of these members of the genus Desulfovibrio are SRB known to be involved in reservoir souring and microbially influenced corrosion (Hubert et al, 2009; Kakooei et al, 2012; Guan et al, 2014) at low salinity and low temperature conditions.…”

Formate‐derived H2, a driver of hydrogenotrophic processes in the root‐zone of a methane‐emitting fen

“…Methanoregula boonei has a pH optimum of pH 5 and is adapted to moderately acidic conditions (Br€ auer et al, 2011). M. boonei and Methanobacterium lacus produce methane from H 2 and CO 2 but not from formate (Br€ auer et al, 2011;Borrel et al, 2012;Cadillo-Quiroz et al, 2014). Methanoregula formicicum can utilize H 2 and formate (Yashiro et al, 2011); however, the detected mcrA sequences were only distantly related to this taxon (83%-86% amino acid sequence similarity).…”

“…The detected Methanoregula-affiliated mcrA sequences were most closely related to species that utilize H 2 and CO 2 rather than formate (e.g., M. boonei, 92%-98% amino acid sequence similarity). Acetate is not utilized for the production of methane by M. boonei and M. lacus but stimulates the growth of these species (Br€ auer et al, 2011;Borrel et al, 2012;Cadillo-Quiroz et al, 2014). Unlike other species of Methanosarcina that can grow on H 2 (Balch et al, 1979), M. horobensis grows on acetate but not on H 2 or formate (Shimizu et al, 2011).…”