Fusicatenibacter saccharivorans gen. nov., sp nova, isolated from human faeces

Three Gram-stain-positive, obligately anaerobic, non-motile, non-spore-forming, spindle-shaped bacterial strains (HT03-11(T), KO-38 and TT-111), isolated from human faeces were characterized by phenotypic and molecular taxonomic methods. Comparative 16S rRNA gene sequencing showed that the strains were highly related to each other genetically (displaying >99% sequence similarity) and represented a previously unknown subline within the Blautia coccoides rRNA group of organisms (cluster XIVa). The closest phylogenetic neighbours of strain HT03-11(T) were Clostridium bolteae WAL 16351(T) (93.7% 16S rRNA gene sequence similarity) and Clostridium saccharolyticum WM1(T) (93.7% similarity). All isolates produced lactic acid, formic acid, acetic acid and succinic acid as fermentation end products from glucose. Their chemotaxonomic properties included lysine as the cell wall diamino acid and C-16:0, C-18:1 omega 7c DMA and C-16:0 DMA as the major fatty acids. The G+C contents of the genomic DNA were 46.9-47.2 mol% (HPLC). Several phenotypic and chemotaxonomic characteristics could be readily used to differentiate the isolates from phylogenetically related clostridia. Therefore, strains HT03-11(T), KO-38 and TY-111 represent a novel species in a new genus of the family Lachnospiraceae, for which the name Fusicatenibacter saccharivorans gen. nov., sp. nov. is proposed. The type strain of the type species is HT03-11(T) (=YIT 12554(T)=JCM 18507(T)=DSM 26062(T)).