Defluviimonas indica sp. nov., a marine bacterium isolated from a deep-sea hydrothermal vent environment

Abstract

A Gram-stain-negative, strictly aerobic, chemoheterotrophic marine bacterium, designated 20V17T, was isolated from a deep-sea hydrothermal vent chimney collected from the South-west Indian Ridge. Cells of strain 20V17T were motile, short rods, 1.2–1.8 µm in length and 0.5–0.7 µm in width. Growth was observed at between 20 and 37 °C (optimum 25 °C–28 °C), pH 5.0 and 8.0 (optimum pH 7.0) and 0.5 and 8 % (w/v) NaCl (optimum 1.5–2.0 % NaCl). The major fatty acids were C18 : 1ω7c (74.4 %), C19 : 0 cyclo ω8c (11 %), C18 : 0 (5.1 %) and C18 : 0 3-OH (2.8 %), and the polar lipid profile comprised diphosphatidylglycerol, phosphatidylethanolamine, an unidentified glycolipid and four unidentified phospholipids. Ubiquinone 10 was the major quinone. The G+C content of genomic DNA was 66.3 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain 20V17T belonged to the genus Defluviimonas and shared 96.5 and 96.1 % sequence similarity with Defluviimonas denitrificans D9-3T and Defluviimonas aestuarii BS14T, respectively. On the basis of the taxonomic data obtained in this study, strain 20V17T represents a novel species of the genus Defluviimonas , for which the name Defluviimonas indica sp. nov. is proposed. The type strain is 20V17T (CGMCC 1.10859T = JCM 17871T = MCCC 1A01802T).