Sphingosinithalassobacter tenebrarum sp. nov., isolated from a deep-sea cold seep

A Gram-stain-negative, facultatively anaerobic, yellow-pigmented, non-motile, rod-shaped bacterium, designated zrk23 T , was isolated from a deep-sea cold seep. The strain was characterized by a polyphasic approach to clarify its taxonomic position. Phylogenetic analysis based on 16S rRNA gene sequences placed zrk23 T within the genus Sphingosinithalassobacter and showed the highest similarity to Sphingosinithalassobacter portus FM6 T (97.93 %). Growth occurs at temperatures from 16 to 45 °C (optimum, 30 °C), at pH values between pH 6.0 and 8.5 (optimum, pH 7.0) and in 0–5.0 % (w/v) NaCl (optimum, 1.5 %). The major fatty acids were C 16 : 0 , C 14 : 0 2-OH and summed feature 8 (C 18 : 1 ω7 c and/or C 18 : 1 ω6 c ). The major isoprenoid quinone was ubiquinone-10. Predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, one unidentified phosphoglycolipid, three unidentified glycolipids and three unidentified phospholipids. The G+C content of the genomic DNA was 64.69 %. The average nucleotide identity values between zrk23 T and the most closely related available genome, of Sphingosinithalassobacter portus FM6 T , was 82.21 %, indicating that zrk23 T was clearly distinguished from S. portus . The analysis of genome sequence of zrk23 T revealed that there were many genes associated with degradation of aromatic compounds existing in the genome of zrk23 T . As a result of the combination of the results of phylogenetic analysis and phenotypic and chemotaxonomic data, zrk23 T was considered to represent a novel species of the genus Sphingosinithalassobacter , for which the name Sphingosinithalassobacter tenebrarum sp. nov. is proposed. The type strain is zrk23 T (=KCTC 72896 T =MCCC 1K04416 T ).