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

Strain C5-48(T), 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 C5-48(T) showed high similarity to the corresponding sequences of Lachnoclostridium edouardi Marseille-P3397(T) (95.7%) and Clostridium fessum SNUG30386(T) (94.7%). However, phylogenetic analysis using the sequences of the 16S rRNA, rpoB, and hsp60 genes and whole-genome analysis strongly suggested that C5-48(T) should be included in the genus Enterocloster. The novelty of strain C5-48(T) 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 16351(T) and Enterocloster clostridioformis ATCC 25537(T), respectively). The temperature range for growth of strain C5-48(T) 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 C5-48(T) were 16:0, 14:0, and 18:1 ω7c dimethyl acetal fatty acids. On the basis of the genotypic and phenotypic properties, Enterocloster alcoholdehydrogenati sp. nov. is proposed, with the type strain C5-48(T) (= JCM 33305(T) = DSM 109474(T)). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00284-023-03285-1.