Roseivivax jejudonensis sp. nov., isolated from the junction between the ocean and a freshwater spring at Jeju island, South Korea

Abstract

A Gram-stain negative, coccoid- or oval-shaped and non-gliding bacterial strain, designated CDM-17T, was isolated from the zone where the ocean and a freshwater sp.ing meet at Jeju island, South Korea, and subjected to a polyphasic taxonomic study. Strain CDM-17T was observed to form smooth, circular, glistening, slightly convex, light yellowish pink colonies on marine agar, and was found to grow optimally at pH 7.0-8.0, at 30 °C and in the presence of 2-3 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain CDM-17T fell within the clade comprising the Roseivivax sp.cies, clustering with the type strain of Roseivivax sediminis with which it exhibited 98.3 % sequence similarity value. Sequence similarities to the type strains of the other recognized Roseivivax sp.cies were 94.7-96.8 %. Strain CDM-17T was found to contain Q-10 as the predominant ubiquinone and summed feature 8 (C18:1ω6c and/or C18:1ω7c) as the major fatty acid. The major polar lipids were identified as phosphatidylcholine, phosphatidylglycerol, an unidentified aminolipid, an unidentified glycolipid and an unidentified lipid. The DNA G+C content of strain CDM-17T was determined to be 66.2 mol% and its mean DNA-DNA relatedness value with Rsv. sediminis KCTC 23444T was 17.5 ± 2.7 %. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain CDM-17T is distinguishable from recognized Roseivivax sp.cies. On the basis of the data presented, strain CDM-17T is proposed to represent a nov.l sp.cies of the genus Roseivivax, for which the name Roseivivax jejudonensis sp. nov. is proposed. The type strain is CDM-17T (=KCTC 42110T = CECT 8625T).