gen. nov., sp. nov., and gen. nov., sp. nov., novel lactate-producing bacteria isolated from mouse intestines, and an emended description of the family .

Two strictly anaerobic, Gram-stain-positive, non-motile bacteria (strains OPF53 and TOC12) were isolated from mouse intestines. Strains OPF53 and TOC12 grew at pH 5.5-9.0 and 5.0-9.0, respectively, and at temperatures of 30-45 °C. The cell morphologies of these strains were short rods and rods, respectively, and the cells possessed intracellular granules. The major cellular fatty acids of OPF53 were C 9 and C 9 dimethyl acetal, whereas those of TOC12 were C and C 9. In OPF53, the main end-products of modified peptone-yeast extract-glucose (PYG) fermentation were lactate, formate and butyrate, whereas, in addition to these acids, TOC12 also produced hydrogen. The genomes of OPF53 and TOC12 were respectively 2.2 and 2.0 Mbp in size with a DNA G+C contents of 69.1 and 58.7 %. The 16S rRNA gene sequences of OPF53 and TOC12 showed the highest similarity to members of the family , namely, Marseille-P2936 (94.3 %) and KCTC 15140 (93.2 %), respectively. Phylogenetic analyses revealed that both isolates formed distinct lineages from other genera of the family . In addition, the two strains were characterized by relatively low 16S rRNA gene sequence similarity (93.4 %) and can be distinguished by their distinctive traits (including cell shape, DNA G+C content, and major fatty acids profiles). On the basis of their polyphasic taxonomic properties, these isolates represent two noel species of two novel genera within the family , for which the names gen. nov., sp. nov. (OPF53=JCM 35015=KCTC 25474) and gen. nov., sp. nov. (TOC12=JCM 35017=KCTC 25472) are proposed.