Halobacterium litoreum sp. nov., isolated from a marine solar saltern

Halophilic archaeal strain ZS-54-S2 was isolated from Zhoushan marine solar saltern, China. Cells were rod-shaped, Gram-stain-negative and formed red-pigmented colonies on an agar plate. Strain ZS-54-S2 was able to grow at 20-50 °C (optimum 35 °C), at 1.7-4.8 M NaCl (optimum 3.9 M), at 0.005-1.0 M MgCl2 (optimum 0.05 M) and at pH 5.0-9.5 (optimum pH 7.0). The cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was found to be 5 % (w/v). The major polar lipids of the strain were phosphatidic acid, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, two glycolipids, which were chromatographically identical to sulfated galactosyl mannosyl galactofuranosyl glucosyl diether and galactosyl mannosyl glucosyl diether, and an unidentified glycolipid, which was chromatographically identical to one detected in Halobacterium salinarum ATCC 33171 . The 16S rRNA gene and rpoB' gene of strain ZS-54-S2 were phylogenetically related to the corresponding genes of Halobacterium noricense JCM 15102 (97.5 % and 90.6 % relatedness, respectively), Halobacterium jilantaiense CGMCC 1.5337 (96.9 and 91.2 %), Halobacterium rubrum CGMCC 1.12575 (96.8 and 90.3 %) and Halobacterium salinarum CGMCC 1.1958 (96.5 and 88.4 %). The DNA G+C content of strain ZS-54-S2 was 66.7 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain ZS-54-S2 (=CGMCC 1.12562 =JCM 30038 ) represents a new species of Halobacterium, for which the name Halobacteriumlitoreum sp. nov. is proposed.