Three moderately acidophilic, halophilic archaeal strains, MH1-243-3T, MH1-243-5 and MH1-243-6, were isolated from a commercial salt sample made from seawater in Okinawa, Japan. Cells of the three strains were pleomorphic and stained Gram-negative. Colonies of the strains were orange–red-pigmented. Strain MH1-243-3T was able to grow at 15–27 % (w/v) NaCl (optimum 24 °C), at pH 4.5–6.5 (pH 5.5) and at 35–50 °C (45 °C). Strains MH1-243-5 and MH1-243-6 grew within slightly different ranges (shown in text). The 16S rRNA gene sequences of the three strains were identical, and the closest phylogenetic relative was Halarchaeum salinum MH1-34-1T with 97.0 % similarity. The rpoB′ gene sequences of the three strains were also identical, and the closest phylogenetic relative was Halarchaeum acidiphilum JCM 16109T with 92.0 % similarity. The DNA G+C content of MH1-243-3T, MH1-243-5 and MH1-243-6 was 65.2 mol%. The levels of DNA–DNA relatedness amongst the three strains were 84.1–99.8 %, while that between MH1-243-3T and H. salinum MH1-34-1T was 30.6 % and 31.6 % (reciprocally), and those between MH1-243-3T and type strains of other species in the genus Halarchaeum were 42.3–29.4 %. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the isolates should represent a novel species of the genus Halarchaeum, for which the name Halarchaeum grantii sp. nov. is proposed. The type strain is MH1-243-3T ( = JCM 19585T = KCTC 4142T), isolated from commercial sea salt produced in Okinawa, Japan. MH1-243-5 ( = JCM 19586) and MH1-243-6 ( = JCM 18422) are additional strains of the species.
An extremely halophilic archaeon, strain S2FP14T, was isolated from a brine sample from 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. 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 that this strain represented a member of the genus Halobellus. 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, 95.2 % to Halobellus rufus CBA1103T, 94.6 % to Halobellus salinus CSW2.24.4T and 94.6 % to Halobellus clavatus TNN18T. 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 and phosphatidylglycerosulfate, plus a very small amount of phosphatidylglycerol and an archaeal analogue of bisphosphatidylglycerol. With regard to glycolipid composition, the most abundant glycolipids were the sulfated diglycosyl diphytanilglyceroldiether and a glycosyl-cardiolipin. 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).