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

Yakult Central Institute for Microbiological Research, 1796 Yaho, Kunitachi, 186-8650 Tokyo, Japan Correspondence Fumiko Nagai fumiko-nagai{at}yakult.co.jp 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 9 c (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 ). Abbreviations: FAME, fatty acid methyl ester; ML, maximum likelihood; MP, maximum parsimony The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain YIT 11859 T is AB370250 . Maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences and a table giving the cellular fatty acid compositions of strain YIT 11859 T and the type strains of related type species in the family Alcaligenaceae are available as supplementary material with the online version of this paper.