A motile, rod-shaped, pink-pigmented, extremely halophilic archaeon, strain SF3-213T, was isolated from a crystallizer pond at the Cargill Solar Salt Plant, Newark, California (USA). Analysis of the almost-complete 16S rRNA gene sequence showed that the isolate was phylogenetically related to species of the genus Halorubrum, with a close relationship to Halorubrum trapanicum NRC 34021T (98.6 % similarity), Halorubrum sodomense ATCC 33755T (98.3 %) and Halorubrum xinjiangense AS 1.3527T (98.2 %). The polar lipids of strain SF3-213T were C20C20 derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and a sulfated diglycosyl-diether. Strain SF3-213T grew in 2.5–5.0 M NaCl. The temperature and pH ranges for growth were 25–42 °C and 6.8–8.5, respectively. Optimal growth occurred at 3.5–4.5 M NaCl, 37 °C and pH 7.3. Mg2+ was required for growth. The DNA G+C content was 69.4 mol%. DNA–DNA hybridization values lower than 70 % were obtained between strain SF3-213T and the closely related species of the genus Halorubrum. Based on the data presented in this study, strain SF3-213T represents a novel species for which the name Halorubrum californiense sp. nov. is proposed; the type strain is SF3-213T (=CECT 7256T=DSM 19288T=JCM 14715T).
A novel extremely halophilic strain, designated XH-65T, isolated from the salt lake Xilinhot in Inner Mongolia, PR China, was subjected to a polyphasic taxonomic characterization. Strain XH-65T is neutrophilic, non-motile and requires at least 2.5 M NaCl for growth, with an optimum at 3.4 M NaCl, and grows at pH 6.0–9.0, with optimum growth at pH 7.5. Strain XH-65T grows at 25–50 °C, with optimal growth at 37 °C. Magnesium is not required for growth. On the basis of 16S rRNA gene sequence analysis, strain XH-65T was shown to belong to the genus Haloterrigena and was related to Haloterrigena turkmenica VKM B-1734T (98.1 % sequence similarity), Haloterrigena saccharevitans AB14T (96.9 %), Haloterrigena thermotolerans PR5T (96.3 %), Haloterrigena limicola AX-7T (95.8 %) and Haloterrigena hispanica FP1T (95.7 %). DNA–DNA hybridization revealed 37 % relatedness between strain XH-65T and Htg. turkmenica VKM B-1734T. The polar lipid composition revealed the presence of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and mannose-2,6-disulfate (1→2)-glucose glycerol diether (S2-DGD). The results of the DNA–DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain XH-65T from the six Haloterrigena species with validly published names. Therefore, strain XH-65T represents a novel species, for which the name Haloterrigena salina sp. nov. is proposed, with the type strain XH-65T (=CGMCC 1.6203T =JCM 13891T).