Gaetbulibacter aquiaggeris sp. nov., a member of the Flavobacteriaceae isolated from seawater

Abstract

A Gram-stain-negative, non-flagellated, non-gliding and rod-shaped bacterial strain, designated KEM-8T, was isolated from seawater in the Korean peninsula. Strain KEM-8Twas found to grow optimally at pH 7.0-8.0, at 30 8C and in the presence of 2-3 % (w/v) NaCl. A neighbourjoining phylogenetic tree based on 16S rRNA gene sequences showed that strain KEM-8T falls within the clade comprising species of the genus Gaetbulibacter, clustering with the type strains of Gaetbulibacter marinus and Gaetbulibacter lutimaris with which it exhibits 98.4 and 97.2 % 16S rRNA gene sequence similarity, respectively. Sequence similarities to Gaetbulibacter saemankumensis SMK-12Tand Gaetbulibacter aestuarii KCTC 23303T were 95.4 and 95.2 %, respectively. Strain KEM-8T was found to contain MK-6 as the predominant menaquinone and iso-C15: 0, iso-C17: 03-OH, iso-C16: 03-OH and iso-C15: 1G as the major fatty acids. The major polar lipids were identified as phosphatidylethanolamine and an unidentified lipid. The DNA G+C content of strain KEM-8Twas 36.0 mol% and mean DNA-DNA relatedness values with G. marinus KCTC 23046Tand G. lutimaris D1-y4Twere 27.6±0.9 and 10.3±1.4 %, respectively. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain KEM-8Tis distinguishable from species of the genus Gaetbulibacter with validly published names. On the basis of the data presented, strain KEM-8Trepresents a novel species of the genus Gaetbulibacter, for which the name Gaetbulibacter aquiaggeris sp. nov. is proposed. The type strain is KEM-8T(=KCTC 42198T=NBRC 110553T).