Gaetbulibacter saemankumensis gen. nov., sp. nov., a novel member of the family Flavobacteriaceae isolated from a tidal flat sediment in Korea

Abstract

Three Gram-negative, yellow-pigmented, rod-shaped bacterial strains, SMK-12T, SMK-36 and SMK-45, were isolated from a tidal flat sediment of the Yellow Sea in Korea, and their taxonomic positions were investigated by a polyphasic approach. The three strains grew optimally at 25-30 °C and in the presence of 2-3% (w/v) NaCl. They contained MK-6 as the predominant menaquinone. The major cellular fatty acids were iso-C15:0, iso-C17:0 3-OH, iso-C15:1, anteiso-C15:0, iso-C15:0 3-OH and C16:1ω7c and/or iso-C15:0 2-OH. The DNA G+C contents of the three strains were 34.7-34.9 mol%. The phylogenetic tree based on 16S rRNA gene sequences revealed that the three strains form one distinct evolutionary lineage supported by a bootstrap value of 100% within the family Flavobacteriaceae. The three strains exhibited 16S rRNA gene sequence similarity levels of 93.8-94.9% to the nearest phylogenetic neighbours, the genera Algibacter, Bizionia and Formosa. On the basis of differences in phenotypic characteristics and phylogenetic distinctiveness, strains SMK-12T, SMK-36 and SMK-45 were classified in a novel genus and species, for which the name Gaetbulibacter saemankumensis gen. nov., sp. nov. is proposed. The type strain for the novel species is SMK-12T (=KCTC 12379T=DSM 17032T).