Sphingobium subterraneum sp. nov., isolated from ground water

Abstract

A Gram-stain-negative, strictly aerobic, non-motile, non-spore-forming, yellow, rod-shaped bacterium, designated S-II-13T, was isolated from ground water at Daejeon in Korea. Strain S-II-13T grew between 15 and 30 6C (optimal growth at 28 6C), between pH 6.0 and 9.0 (optimal growth at pH 7.5) and at salinities of 0.3-1.5% (w/v) NaCl, growing optimally with 0.5% (w/v) NaCl. On the basis of 16S rRNA gene sequence analysis, strain S-II-13T was found to belong to the genus Sphingobium, showing closest phylogenetic similarity to Rhizorhapis suberifaciens CA1T (97.0% 16S rRNA gene sequence similarity), Sphingobium sufflavum HL-25T (96.9%) and Sphingobium vulgare HU1-GD12T (96.6%). The major polar lipids were phosphatidylgly-cerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylcholine and sphingoglycolipid. The predominant ubiquinone was Q-10. The major fatty acids were C18:1v7c, C14:0 2-OH, C16:0 and summed feature 3 (C16:1v7c and/or iso-C15:0 2-OH). The DNA G+C content of strain S-II-13T was 63.5 mol%. DNA-DNA relatedness between strain S-II-13T and Rhizorhapis suberifaciens LMG 17323T, Sphingobium sufflavum KCTC 23953T and Sphingobium vulgare KCTC 22289T was 24, 52 and 55%, respectively. On the basis of evidence from this taxonomic study using a polyphasic approach, strain S-II-13T represents a novel species of the genus Sphingobium for which the name Sphingobium subterraneum sp. nov. is proposed. The type strain is S-II-13T (5KACC 17606T5NBRC 109814T).