Flavobacterium okayamense sp. nov. isolated from surface seawater

Strain KK2020170(T), a Gram-stain negative, yellow colony-forming bacterium, was isolated from surface seawater sampled in Kojima Bay, Okayama, Japan. Phylogenetic analysis based on the 16S rRNA gene revealed that strain KK2020170(T) belongs to the genus Flavobacterium, with Flavobacterium haoranii LQY-7(T) (98.1% similarity) being its closest relative, followed by Flavobacterium sediminis MEBiC07310(T) (96.9%) and Flavobacterium urocaniciphilum YIT 12746(T) (96.0%). Whole-genome shotgun sequencing showed that strain KK2020170(T), when paralleled with F. haoranii LQY-7( T), had 81.3% average nucleotide identity, and 24.6% in silico DNA–DNA hybridization values, respectively. The DNA G + C content of strain KK2020170(T) was 31.1 mol%. The most abundant fatty acids (> 10%) of strain KK2020170(T) were iso-C15: 0, iso-C17: 0 3-OH and iso-C15: 1 G. The dominant respiratory quinone of the strain was menaquinone MK-6. Based on the phylogenetic and phenotypic analysis results, we propose that strain KK2020170(T) represents a novel species, for which the name Flavobacterium okayamense sp. nov. has been proposed. The type strain is KK2020170(T) (= ATCC TSD-280( T) = NBRC 115344( T)). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00203-023-03682-x.