Psychroflexus aestuariivivens sp. nov., isolated from a tidal flat

Abstract

A Gram-stain-negative, aerobic, non-flagellated, non-gliding and ovoid or rod-shaped bacterium, designated DB-3T, was isolated from a tidal flat on the Yellow Sea in South Korea, and subjected to a taxonomic study using a polyphasic approach. Strain DB-3T grew optimally at 30°C, at pH 7.0-8.0 and in the presence of 2.0-3.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences showed that strain DB-3T fell within the clade comprising the type strains of species of the genus Psychroflexus. Strain DB-3T exhibited 16S rRNA gene sequence similarities of 93.2-96.9 % to the type strains of species of the genus Psychroflexus. Strain DB3T contained MK-6 as the predominant menaquinone and iso-C15:0, anteiso-C15:0 and iso-C17:0 3-OH as the major fatty acids. The major or significant amounts of polar lipids detected in strain DB-3T were phosphatidylethanolamine, an unidentified aminolipid and seven unidentified lipids. The DNA G+C content was 34.7 mol%. Differential phenotypic properties, together with phylogenetic distinctiveness, revealed that strain DB-3T is separated from recognized species of the genus Psychroflexus. On the basis of the data presented, strain DB-3T is considered to represent a novel species of the genus Psychroflexus, for which the name Psychroflexus aestuariivivens sp. nov. is proposed. The type strain is DB-3T (=KCTC 52037T=NBRC 111757T).