Enterocloster alcoholdehydrogenati sp. nov., a Novel Bacterial Species Isolated from the Feces of a Patient with Alcoholism.

ABSTRACT

Strain C5-48T, an anaerobic intestinal bacterium that potentially accumulates acetaldehyde at levels exceeding its minimum mutagenic concentration (50 µM) in the colon and rectum, was isolated from the feces of a patient with alcoholism. The 16S rRNA gene sequence of strain C5-48T showed high similarity to the corresponding sequences of Lachnoclostridium edouardi Marseille-P3397T (95.7%) and Clostridium fessum SNUG30386T (94.7%). However, phylogenetic analysis using the sequences of the 16S rRNA, rpoB, and hsp60 genes and whole-genome analysis strongly suggested that C5-48T should be included in the genus Enterocloster. The novelty of strain C5-48T was further confirmed by comprehensive average nucleotide identity (ANI) calculations based on its whole-genome sequence, which showed appreciable ANI values with known Enterocloster species (e.g., 74.3% and 73.4% with Enterocloster bolteae WAL 16351T and Enterocloster clostridioformis ATCC 25537T, respectively). The temperature range for growth of strain C5-48T was 15-37 °C with an optimum of 37 °C. The pH range for growth was 5.5-10.5 with an optimum of 7.5. The major constituents of the cell membrane lipids of strain C5-48T were 160, 140, and 181 ω7c dimethyl acetal fatty acids. On the basis of the genotypic and phenotypic properties, Enterocloster alcoholdehydrogenati sp. nov. is proposed, with the type strain C5-48T (= JCM 33305T = DSM 109474T).