Description of a new member of the family Erysipelotrichaceae: Clostridium fusiformis sp. nov., isolated from healthy human feces

A Gram-positive, non-motile, rod-shaped facultative anaerobic bacterial strain SG502^T was isolated from the healthy human fecal samples in Brookings, SD, USA. The comparison of the 16S rRNA gene placed the strain within the Clostridium cluster XVI, where, Clostridium innocuum ATCC 14501^T, Longicatena caecimuris strain PG-426-CC-2, Eubacterium dolichum DSM 3991^T and Eubacterium tortuosum DSM 3987^T were its closest taxa with 95.15%, 94.49%, 93.28%, and 93.20% sequence identities respectively. The optimal growth temperature and pH for the strain SG502^T were 37°C and 7.0 respectively. Acetate was the major short-chain fatty acid product of the strain SG502^T when grown in BHI-M medium. The major cellular fatty acids produced by the strain SG502^T were C_18:1 ω9c, C_18:0 and C_16:0. The DNA G+C content of the strain was 34.34 mol%. The average nucleotide identity of the genome of the strain SG502^T and its closest neighbor C. innocuum ATCC 14501^T was 63.48%. Based on the polyphasic analysis, the type strain SG502^T (=DSM 107282^T), represents a novel species of the genus Clostridium for which the name Clostridium fusiformis sp. nov. is proposed.