Tessaracoccus antarcticus sp. nov., a rhodopsin-containing bacterium from an Antarctic environment and emended description of the genus Tessaracoccus

Abstract

A Gram-stain-positive, facultatively anaerobic bacterium, strain JDX10 T , was isolated from a soil sample of Fildes Peninsula, Antarctica. Cells of the strain were irregular rod-shaped and non-motile. Cells grew at 4–40 °C (optimum, 28 °C), at pH 6.0–9.0 (optimum, 7.5) and with 0.0–3.0 % (w/v) NaCl (optimum, 1.0 %). According to phylogenetic analysis based on 16S rRNA gene sequences, strain JDX10 T was associated with the genus Tessaracoccus , and showed highest similarities to Tessaracoccus rhinocerotis CCTCC AB 2013217 T (97.2 %), Tessaracoccus flavescens SST-39 T (96.9 %) and Tessaracoccus terricola JCM 32157 T (96.9 %). The average nucleotide identity scores of strain JDX10 T to T. rhinocerotis CCTCC AB 2013217 T and T. bendigoensis JCM 13525 T were 74.8 and 73.3 %, respectively and the Genome-to-Genome Distance Calculator scores were 19.2 and 18.7 %, respectively. The major (>10.0 %) cellular fatty acid was anteiso-C 15 : 0 . The predominant isoprenoid quinone was MK-10(H 4 ). The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and one unidentified glycolipid. The phylogenetic analysis and physiological and biochemical data showed that strain JDX10 T should be classified as representing a novel species in the genus Tessaracoccus , for which the name Tessaracoccus antarcticus sp. nov. is proposed. The type strain is JDX10 T (=MCCC 1H00351 T =KCTC 49242 T ).