Halorubrum tibetense sp. nov., a novel haloalkaliphilic archaeon from Lake Zabuye in Tibet, China.

A novel haloalkaliphilic archaeon, strain 8W8T, was isolated from Lake Zabuye, on the Tibetan Plateau, China. On the basis of 16S rRNA gene sequence analysis, strain 8W8T was shown to belong to the genus Halorubrum and was related to Halorubrum vacuolatum (96.7% sequence similarity), Halorubrum saccharovorum (96.0%), Halorubrum lacusprofundi (95.4%) and Halorubrum sodomense (95.3%). The phylogenetic distance from any species within the other genera of Halobacteriales was lower than 90%. The major polar lipids of strain 8W8T were C20C20 and C20C25 derivatives of phosphatidylglycerol phosphate and phosphatidylglycerol phosphate methyl ester. The results of DNA-DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain 8W8T from the eight Halorubrum species with validly published names. Therefore, strain 8W8T represents a novel species, for which the name Halorubrum tibetense sp. nov. is proposed, with the type strain 8W8T (=AS 1.3239T=JCM 11889T).