Roseivivax sediminis sp nov., a moderately halophilic bacterium isolated from salt mine sediment

A Gram-negative, facultatively anaerobic, short rod-shaped, heterotrophic bacterium, designated strain VIM D21(T), was isolated from a salt mine in Yunnan province, south-west China. Strain VIM D21(T) formed cream yellow colonies, was non-motile and moderately halophilic, and tolerated NaCl concentrations of 1-15% (w/v), with optimum growth at 5-10% (w/v). Growth occurred at 15-42 degrees C (optimum 28 degrees C) and at pH 6.5-8.5 (optimum 7.5-8.0). The respiratory quinone was ubiquinone-10 (0-10). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, three unidentified phospholipids, one unidentified aminolipid and two unidentified lipids. The major fatty acids were C-18:1 omega 7c and cyclo C-19:0 omega 8c and the DNA G+C content was 67.7 mol%. Phylogenetic analyses revealed that strain VIM D21(T) belongs to the genus Roseivivax. 16S rRNA gene sequence similarities of VIM D21(T) were 95.7, 95.0 and 94.8% with the type strains of Roseivivax halodurans, Roseivivax lentus and Roseivivax halotolerans, respectively. Physiological and biochemical tests allowed phenotypic differentiation of strain VIM D21(T) from closely related species with validly published names. We therefore propose that this isolate represents a novel species, Roseivivax sediminis sp. nov.; the type strain is YIM D21(T) (=KCTC 23444(T)=ACCC 10710(T)).