Nitratireductor indicus sp. nov., isolated from deep-sea water

Abstract

A taxonomic study was carried out on a novel bacterial strain, designated C115T, isolated from a crude-oil-degrading consortium, enriched from deep-sea water of the Indian Ocean. Cells were Gram-negative short rods, mobile by means of a monopolar flagellum. Growth was observed at salinities of 0–7 % and at 10–43 °C. It was unable to degrade Tween 80 or gelatin. 16S rRNA gene sequence analysis showed that strain C115T was related most closely to Nitratireductor aquibiodomus NL21T (96.5 % similarity), Nitratireductor kimnyeongensis KY 101T (96.4 %) and Nitratireductor basaltis J3T (96.2 %). The predominant fatty acids were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c, 81.8 %) and C18 : 0 (7.0 %). The G+C content of the chromosomal DNA of strain C115T was 59 mol%. Based on its morphology, physiology and fatty acid composition together with 16S rRNA gene sequence comparisons, the novel strain most appropriately belongs to the genus Nitratireductor, but can be distinguished readily from recognized species of the genus. Strain C115T is therefore considered to represent a novel species of the genus Nitratireductor, for which the name Nitratireductor indicus sp. nov. is proposed. The type strain is C115T (=RC92-7T =CCTCC AB 209298T =LMG 25540T =MCCC 1A01260T).