Sphingomonas antarctica sp. nov., isolated from Antarctic tundra soil

Strain 200^T, isolated from a soil sample taken from Antarctic tundra soil around Zhongshan Station, was found to be a Gram-stain-negative, yellow-pigmented, catalase-positive, oxidase-negative, non-motile, non-spore-forming, rod-shaped and aerobic bacterium. Strain 200^T grew optimally at pH 7.0 and in the absence of NaCl on R2A. Its optimum growth temperature was 20 °C. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 200^T belonged to the genus Sphingomonas. Strain 200^T showed the highest sequence similarities to Sphingomonas kyeonggiense THG-DT81^T (95.1 %) and Sphingomonas molluscorum KMM 3882^T (95.1 %). Chemotaxonomic analysis showed that strain 200^T had characteristics typical of members of the genus Sphingomonas. Ubiquinone 10 was the predominant respiratory quinone and sym-homospermidine was the polyamine. The major polar lipids were sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylcholine. The G+C content of the genomic DNA was determined to be 60.9 mol%. Strain 200^T contained C16 : 0 (31.6 %), summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c, 22.7 %), summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c, 11.2 %), C18 : 0 (7.8 %) and C14 : 0 2OH (6.7 %) as the major cellular fatty acids. On the basis of phylogenetic analysis, and physiological and biochemical characterization, strain 200^T should be classified as representing a novel species of the genus Sphingomonas, for which the name Sphingomonasantarctica sp. nov. is proposed. The type strain is 200^T (=CCTCC AB 2016064^T=KCTC 52488^T).