Pseudorhodobacter ponti sp. nov., isolated from seawater

Abstract

A Gram-stain-negative, short-rod-shaped, non-motile bacterial strain, designated HWR-46T, was isolated from seawater of the Yellow Sea, South Korea, and was subjected to a polyphasic taxonomic study. Strain HWR-46T grew optimally at pH 7.0-8.0, at 20-25 °C and in the presence of 2-3% (w/v) NaCl. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain HWR-46T fell within the clade comprising Pseudorhodobacter species, clustering with the type strain of Pseudorhodobacter aquimaris, with which it exhibited 98.4% sequence similarity. 16S rRNA gene sequence similarity between strain HWR-46T and the type strains of other Pseudorhodobacter species was 95.1-96.3 %. The DNA G+C content of strain HWR- 46T was 63.1 mol% and its mean DNA-DNA relatedness value with P. aquimaris HDW-19T was 24.6±1.5 %. Strain HWR-46T contained only Q-10 as the ubiquinone and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) as the major fatty acid. The major polar lipids were phosphatidylcholine, phosphatidylglycerol, an unidentified aminolipid and an unidentified aminophospholipid. Differential phenotypic properties, together with phylogenetic distinctiveness, demonstrated that strain HWR-46T is distinguishable from other Pseudorhodobacter species. On the basis of the data presented, strain HWR-46T is considered to represent a novel species of the genus Pseudorhodobacter, for which the name Pseudorhodobacter ponti sp. nov. is proposed. The type strain is HWR-46T (=KCTC 52470T=NBRC 112426T).