Salinarubrum litoreum gen. nov., sp. nov.: a new member of the family Halobacteriaceae isolated from Chinese marine solar salterns

Three halophilic archaeal strains, XD46^T, YJ-63-S1 and ZS-1-H, were isolated from three Chinese marine solar salterns. All were observed to have pleomorphic cells that lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. They were found to grow optimally at 37 °C, at pH 7.0 and in the presence of 2.6 M NaCl and 0.05 M Mg²⁺. The major polar lipids were identified as those typical for members of the Halobacteriaceae but also included major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1), mannosyl glucosyl diether (DGD-1) and two unidentified ones. The 16S rRNA gene sequences of the three strains were 99.8–100 % identical, showing most similarity to sequences of members of the family Halobacteriaceae, and clustering together as a distinct clade in phylogenetic tree reconstructions. The rpoB′ gene similarities between the three strains were 98.7–100 % and lower to the sequences of other halobacteria. Their DNA G+C contents were determined to be 65.1–65.5 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains XD46^T (=CGMCC 1.12237^T = JCM 18649^T), YJ-63-S1 (=CGMCC 1.12574) and ZS-1-H (=CGMCC 1.12544) represent a novel species in a new genus within the family Halobacteriaceae, for which the name Salinarubrum litoreum gen. nov., sp. nov. is proposed.