Sphingorhabdus arenilitoris sp. nov., isolated from a coastal sand, and reclassification of Sphingopyxis rigui as Sphingorhabdus rigui comb. nov. and Sphingopyxis wooponensis as Sphingorhabdus wooponensis comb. nov.

Abstract

A Gram-stain-negative, strictly aerobic, non-flagellated and rod-shaped bacterial strain, designated GJR-7T, was isolated from coastal sand of the South Sea of South Korea. Strain GJR-7T grew optimally at 30 °C, at pH 7.0-7.5 and without NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain GJR-7T clustered with the type strains of Sphingopyxis wooponensis, Sphingopyxis rigui and Sphingorhabdus planktonica, with which it exhibited 16S rRNA gene sequence similarity values of 96.0-96.3 %. Sequence similarities to the type strains of other recognized species were less than 95.5 %. Strain GJR-7T contained Q-10 as the predominant ubiquinone and C18: 1ω7c, 11-methyl C18: 1ω7c and summed feature 3 (C16: 1ω7c and/or C16: 1ω6c) or C14: 0 2-OH. The major polar lipids were sphingoglycolipid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and one unidentified glycolipid. The DNA G+C content of strain GJR-7T was 55.5 mol%. Differential phenotypic properties, together with phylogenetic distinctiveness, revealed that strain GJR-7T is separated from the type strains of Sphingopyxis wooponensis, Sphingopyxis rigui and Sphingorhabdus planktonica. On the basis of the data presented, strain GJR-7Tis considered to represent a novel species of the genus Sphingorhabdus, for which the name Sphingorhabdus arenilitoris sp. nov. is proposed. The type strain is GJR-7T (= KCTC 42051T = CECT 8531T). It is also proposed that Sphingopyxis wooponensis and Sphingopyxis rigui should be reclassified as members of the genus Sphingorhabdus.