Parasutterella excrementihominis gen. nov., sp. nov., a member of the family Alcaligenaceae isolated from human faeces.

A novel, strictly anaerobic, non-spore-forming, Gram-negative coccobacillus (strain YIT 11859(T)) was isolated from human faeces. Biochemically, this strain was largely unreactive and was asaccharolytic. Growth of strain YIT 11859(T) in peptone-yeast extract broth produced no visible turbidity, and a trace amount of propionate was detected as an end product of metabolism. 16S rRNA gene sequence analysis showed that strain YIT 11859(T) was related most closely to the type strains of Sutterella species, with 90.8-88.0 % sequence similarity. Phylogenetic analysis of these and other related sequences confirmed that strain YIT 11859(T) was phylogenetically most closely associated with Sutterella species, but formed a separate cluster, indicating that strain YIT 11859(T) represents a novel member of the family Alcaligenaceae. Fatty acid analysis demonstrated the presence of a high concentration of C(18 : 1)omega9c (75 % of the total). The main respiratory quinones were menaquinone (MK-6) and methylated menaquinone (MMK-6). The G+C content of the DNA was 49.8 mol%. These results suggest that strain YIT 11859(T) represents a novel species of a new genus, for which the name Parasutterella excrementihominis gen. nov., sp. nov. is proposed. The type strain of Parasutterella excrementihominis is YIT 11859(T) (=DSM 21040(T) =JCM 15078(T)).