Georgenia halophila sp. nov., a halophilic actinobacterium isolated from a salt lake

Abstract

A Gram-stain-positive actinobacterium, designated strain YIM 93316T, was isolated from a salt lake in Xinjiang Province, north-west China, and was subjected to a polyphasic taxonomic study. The isolate grew at 10–45 °C, at pH 6–9 and in the presence of 1–15 % (w/v) NaCl, but no growth was observed in the absence of NaCl. The cell-wall diamino acid contained alanine, glutamine and lysine with peptidoglycan type A4α. Polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides, an unknown glycolipid and an unknown phospholipid. The predominant menaquinone was MK-8(H4). The major fatty acids were anteiso-C15 : 0 and anteiso-C15 : 1. The DNA G+C content of strain YIM 93316T was 70.1 mol%. Chemotaxonomic properties supported the affiliation of strain YIM 93316T to the genus Georgenia, and this was supported by phylogenetic analysis based on 16S rRNA gene sequences. Levels of 16S rRNA gene sequence similarity between strain YIM 93316T and Georgenia thermotolerans TT02-04T, Georgenia ruanii YIM 004T and Georgenia muralis 1A-CT were 96.6, 96.5 and 96.3 %, respectively. Data from fatty acid, physiological and biochemical tests allowed the clear phenotypic differentiation of strain YIM 93316T from recognized members of the genus Georgenia. On the basis of evidence from the present polyphasic study, strain YIM 93316T is considered to represent a novel species of the genus Georgenia, for which the name Georgenia halophila sp. nov. is proposed. The type strain is YIM 93316T (=DSM 21365T =CCTCC AB 208144T).