Salinigranum rubrum gen. nov., sp. nov., a member of the family Halobacteriaceae isolated from a marine solar saltern

Abstract

Halophilic archaeal strain GX10(T) was isolated from the Gangxi marine solar saltern in China. Strain GX10(T) was observed to have pleomorphic cells that lysed in distilled water, stained Gram-negative and produced red-pigmented colonies. Strain GX10(T) was able to grow at 20-50 °C (optimum 37 °C), with 1.4-4.8 M NaCl (optimum 3.1 M NaCl), with 0-0.7 M MgCl2 (optimum 0.05 M MgCl2) and at pH 5.0-9.0 (optimum pH 7.0). The major polar lipids of strain GX10(T) were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, two major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether and mannosyl glucosyl diether, and five unidentified glycolipids. Phylogenetic tree reconstructions based on 16S rRNA gene and rpoB' sequences revealed that strain GX10(T) was distinct from the related genera, Halogranum, Haloferax, Halopelagius, Halogeometricum, Halobellus, Haloplanus and Halorubrum. The DNA G+C content of strain GX10(T) was 62.9 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain GX10(T) represents a novel species of a new genus within the family Halobacteriaceae, for which the name Salinigranum rubrum gen. nov., sp. nov. is proposed. The type strain of the type species is GX10(T) ( = CGMCC 1.10385(T) = JCM 17116(T)).