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-12(T), 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 degrees 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-C(15:0), iso-C(17:0) 3-OH, iso-C(15:1), anteiso-C(15:0), iso-C(15:0) 3-OH and C(16:1)omega7c and/or iso-C(15:0) 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-12(T), 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-12(T) (=KCTC 12379(T)=DSM 17032(T)).