Halorubrum salsamenti sp. nov., a Novel Halophilic Archaeon Isolated from a Brine of Salt Mine.

A non-motile, spherical or oval extremely halophilic archaeon, strain Y69, was isolated from a brine of the Yunnan salt mine, China. Colonies on JCM 168 agar plate were round (1-2 mm in diameter), moist, and orange-pigmented. Phylogenetic analysis of the almost-complete 16S rRNA gene sequence showed that the isolate belonged to the species of the genus Halorubrum, with a close relationship to Halorubrum aidingense 31-hong (98.5%), Halorubrum lacusprofundi ATCC 49239 (98.2%), and Halorubrum kocurii BG-1 (98.0%). The major polar lipids of strain Y69 were phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and a sulfated diglycosyl diether. Strain Y69 grew in 15-30% (w/v) NaCl. The temperature and pH ranges for growth were 25-50 °C and 6.5-9.0, respectively. Optimal growth occurred at 20% (w/v) NaCl, 42 °C, and pH 8.0. Mg was required for growth. The DNA G+C content was determined to be 65.1 mol% by the thermal denaturation method. DNA-DNA hybridization values between strain Y69 and the closely related species were lower than 70%. Based on the data presented in this study, strain Y69 represents a novel species for which the name Halorubrum salsamenti sp. nov. is proposed. The type of the strain is Y69 (=CGMCC 1.15455 = JCM 31270). [ABSTRACT FROM AUTHOR]