Roseovarius antarcticus sp. nov., isolated from a decayed whale bone

Abstract

A pale yellow, ovoid- to rod-shaped and budding bacterium, designated strain M-S13-148T, was isolated from a decayed bone of whale from the eastern coast of King George Island, South Shetlands, Antarctica. Strain M-S13-148T exhibited motility, aerobic growth and was Gram-stain-negative. Strain M-S13-148T was positive for catalase and oxidase. Growth was observed at pH 6.0–9.0, at 4–42 °C and with 0–14 % (w/v) NaCl. The novel strain contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and an unknown phospholipid as the major polar lipids. The dominant cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), (58.8 %) and C16 : 0 (11.7 %). The respiratory quinone was Q-10 and the DNA G+C content was 60.9 mol%. Neighbour-joining, maximum-likelihood and minimum-evolution phylogenetic trees, based on 16S rRNA gene sequences, indicated that strain M-S13-148T belonged to the genus Roseovarius and was most closely related to Roseovarius nanhaiticus CCTCC AB 208317T (93.72 % 16S rRNA gene sequence similarity). The 16S rRNA gene sequence similarity with respect to members of the genus Roseovarius ranged from 91.81 to 93.94 %. On the basis of phenotypic, molecular and chemotaxonomic characteristics, strain M-S13-148 is considered to represent a novel species of the genus Roseovarius, for which the name Roseovarius antarcticus sp. nov., is proposed. The type strain is M-S13-148T ( = CCTCC AB2014072T = LMG 28420T).