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

Abstract

Three Gram-stain-positive, obligately anaerobic, non-motile, non-spore-forming, spindle-shaped bacterial strains (HT03-11T, 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 HT03-11T were Clostridium bolteae WAL 16351T (93.7 % 16S rRNA gene sequence similarity) and Clostridium saccharolyticum WM1T (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 C16 : 0, C18 : 1ω7c DMA and C16 : 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 HT03-11T, KO-38 and TT-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 HT03-11T ( = YIT 12554T = JCM 18507T = DSM 26062T).