Blautia hominis sp. nov., isolated from human faeces

A strictly anaerobic, Gram-stain-positive, non-motile and coccoid- or oval-shaped bacterium, designated strain KB1 T , was isolated from a faecal sample of a patient with diverticulitis in South Korea. Degeneracies in the 16S rRNA gene sequence of strain KB1 T were resolved by cloning, which yielded five different sequences with heterogeneity. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain KB1 T formed a monophyletic branch with species in the genus Blautia, with highest sequence similarity to the type strain of Blautia producta (97.7-98.9 %), followed by Blautia coccoides (97.5-98.1 %). Strain KB1 T was able to grow at temperatures of between 15 and 42 °C, with optimal growth at 37 °C, and in the presence of 20 % dehydrated bile. Acetic acid, succinic acid, lactic acid and fumaric acid were produced by strain KB1 T from Gifu anaerobic medium broth as metabolic fermentation end-products. The major cellular fatty acids of strain KB1 T were C14 : 0, C16 : 0 and C16 : 0 dimethyl aldehyde. The DNA G+C content was 46.3 mol%. The average nucleotide identity value between strain KB1 T and the type strain of B. producta was 84.1 %. On the basis of polyphasic analysis, strain KB1 T represents a novel species in the genus Blautia, for which the name Blautia hominis sp. nov. is proposed. The type strain is KB1 T (=KCTC 15618 T =JCM 32276 T ).