Vitellibacter soesokkakensis sp. nov., isolated from the junction between the ocean and a freshwater spring and emended description of the genus Vitellibacter

Abstract

A Gram-stain-negative, aerobic, non-spore-forming, non-flagellated, motile by gliding and rodshaped bacterial strain, RSSK-12T, was isolated from the zone where the ocean and a freshwater spring meet at Jeju island, South Korea. Strain RSSK-12T grew optimally at 30 °C, at pH 7.0-8.0 and in the presence of 2.0-3.0% (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain RSSK-12T clustered with the type strains of two Vitellibacter species, with which it exhibited 94.8-96.9% sequence similarity. Sequence similarities to the type strains of species of the genus Aequorivita and of other recognized species were 94.7-95.5% and less than 91.9 %, respectively. Strain RSSK-12T contained MK-6 as the predominant menaquinone and iso-C15: 0 and iso-C17: 0 3-OH as the major fatty acids. The major polar lipids of strain RSSK-12T were phosphatidylethanolamine and one unidentified lipid. The DNA G+C content of strain RSSK-12T was 38.9 mol%. Differential phenotypic properties, together with phylogenetic distinctiveness, revealed that strain RSSK-12T is separate from other Vitellibacter species. On the basis of the data presented, strain RSSK-12T is considered to represent a novel species of the genus Vitellibacter, for which the name Vitellibacter soesokkakensis sp. nov. is proposed. The type strain is RSSK-12T (5KCTC 32536T5CECT 8398T).