Polyphasic taxonomy of new genus Kaistella koreensis gen. nov., sp. nov. in flavobacteriaceae

Abstract

Gram-negative, rod-shaped, non-spore-forming, yellow-pigmented bacteria isolated from a freshwater stream in Korea were investigated to determine their taxonomic status. Complete 16S rRNA gene sequence analysis indicated that the organisms should be placed in the Chryseobacterium-Bergeyella-Riemerella branch in the family, Flavobacteriaceae. Phylogenetically, the strains were most closely related to Chryseobacterium scophthalmum LMG $13028^T$ and Chryseobacterium joostei $lx 5a^T (=LMG 18212^T)$ (93.9% and 92.7% 16S rRNA gene sequence similarity, respectively) and they clustered their own peculiar branch. The strains contained menaquinone MK-6 as the predominant menaquinone and higher G+C mol% (41.7%) than other type strains in the Chryseobacterium-Bergeyella-Riemerella branch and contained $i-C_{15:0}$ as major fatty acid $i-C_{13:0}$, $anteiso-C_{15:0}$ as their own discriminative specific fatty acids. The phylogenetic distances from any validly described type strains and their phenotypic properties confirmed that the strains constitute a separate genus for which the name Kaistella koreensis gen. nov., sp. nov. $(type strain Chj707^T = KCTC 12107^T = IAM 15050^T)$ is proposed.