Collinsella urealyticum sp. nov., a urease-positive bacterial strain isolated from swine faeces

A novel actinobacterial strain, designated AGMB00827^T, was isolated from swine faeces. Strain AGMB00827^T was obligately anaerobic, Gram-stain-positive, non-motile, non-spore-forming and rod-shaped bacterium. Comparative analyses based on the 16S rRNA gene and whole genome sequence revealed that strain AGMB00827^T was affiliated to the genus Collinsella, and was most closely related to Collinsella vaginalis Marseille-P2666^T (= KCTC 25056^T). Biochemical analysis showed strain AGMB00827^T was negative for catalase and oxidase. Interestingly, strain AGMB00827^T possessed urease activity, which was determined by traditional methods (API test and Christensen's urea medium), unlike related strains. Furthermore, the major cellular fatty acids (> 10%) of the isolate were C_18:1 ω9c, C_16:0, C_16:0 DMA and C_18:2 ω9,12c DMA. Based on the whole genome sequence analysis, the DNA G + C content of strain AGMB00827^T was 52.3%, and the genome size and numbers of rRNA and tRNA genes were 1,945,251 bp, 3 and 46, respectively. The average nucleotide identity and digital DNA-DNA hybridization values between strain AGMB00827^T and C. vaginalis KCTC 25056 ^T were 71.0 and 23.2%, respectively. Additionally, the genome analysis revealed that strain AGMB00827^T possesses urease gene cluster including ureABC and ureDEFG while the related strains do not have those genes, which is consistent with the urease activity. On the basis of polyphasic taxonomic approach, strain AGMB00827^T represents a novel species within the genus Collinsella, for which the name Collinsella urealyticum sp. nov. is proposed. The type strain is AGMB00827^T (= KCTC 25287^T = GDMCC 1.2724^T).