Halobellus ramosii sp. nov., an extremely halophilic archaeon isolated from a saline-wetland wildfowl reserve.

An extremely halophilic archaeon, strain S2FP14T was isolated from a brine sample of the inland hypersaline lake Fuente de Piedra, a saline-wetland wildfowl reserve located in the province of Málaga in southern Spain. Colonies were red pigmented and the cells were Gram-staining-negative, motile and pleomorphic. Strain S2FP14T was able to grow in media containing 12.5-30% (w/v) total salts (optimum 20%) at pH 7-8.5 (optimum 7.5) and at 25-50°C (optimum 37°C). The 16S rRNA gene sequence analysis indicated this strain was a member of the genus Halobellus. The strain S2FP14T showed a similarity of 99.5 % to Halobellus inordinatus YC20T, 96.1% to Halobellus litoreus GX31T, 95.9% to Halobellus limi TBN53T, 95.5 % to Halobellus rarus YC21T, 95.0% to Halobellus rufus CBA1103T, 94.6% to Halobellus salinus CSW2.24.4T and 94.6 % to Halobellus clavatus TNN18T. Besides, the rpoB' gene sequence similarity of strain S2FP14T was 97.4% to 87.6% with members of genus Halobellus. The major phospholipids of strain S2FP14T were phosphatidylglycerol phosphate methyl ester (PGP-Me) and phosphatidylglycerosulfate (PGS), plus a very small amount of phosphatidylglycerol (PG) and an archaeal analogue of bisphosphatidylglycerol (BPG). Regarding glycolipid composition, the most abundant glycolipids were the sulfated diglycosyl diphytanilglyceroldiether (S-DGD) and the glycosyl-cardiolipin (S-DGD-PA). The G+C content of strain S2FP14T genomic DNA was 61.4 mol%. The DNA-DNA hybridization between strain S2FP14T and Halobellus inordinatus JCM 18361T was 51%. Based on the phylogenetic, phenotypic and chemotaxonomic features, a novel species, Halobellus ramosii sp. nov. is proposed. The type strain is S2FP14T (= CECT 8167T = DSM 26177T).