Coprobacter secundus subsp. similis subsp. nov. and Solibaculum mannosilyticum gen. nov., sp. nov., isolated from human feces.

Abstract

An obligately anaerobic, Gram-stain-negative, rod-shaped bacterium, designated strain 2CBH44T , was isolated from the fecal sample of a healthy Japanese man. This strain was initially assigned as a novel species of the genus Coprobacter based on the 16S rRNA gene sequence similarities compared with other Coprobacter species. The 16S rRNA gene sequence analysis revealed strain 2CBH44T had relatively low 16S rRNA gene sequence similarity (97.5%) to Coprobacter secundus 177T . However, strain 2CBH44T showed 96.9% average nucleotide identity value with C. secundus 177T , indicating that strain 2CBH44T and C. secundus 177T belong to the same species. On the other hand, the digital DNA-DNA hybridization value between strain 2CBH44T and C. secundus 177T was 73.5%, indicating that strain 2CBH44T is a subspecies of C. secundus. Another anaerobic, Gram-stain-variable, rod-shaped bacterium, designated strain 12CBH8T , was also isolated from human feces. Strain 12CBH8T had significantly low 16S rRNA gene sequence similarities (<92.0%) to the validated bacterial species within the family Oscillospiraceae. The percentage of conserved protein values between the genome of strain 12CBH8T and that of the validated related taxa were <50%, suggesting that strain 12CBH8T belongs to a novel genus. On the basis of the collected data, strain 2CBH44T represents a novel subspecies of C. secundus, for which the name Coprobacter secundus subsp. similis subsp. nov. (type strain 2CBH44T = JCM 34079T = DSM 111570T ) is proposed. Strain 12CBH8T represents a novel species of a novel genus, for which the name Solibaculum mannosilyticum gen. nov., sp. nov. (type strain 12CBH8T = JCM 34081T = DSM 111571T ) is proposed.