Halorubrum glutamatedens sp. nov., a Halophilic Archaeon Isolated from a Rock Salt

An extremely halophilic archaeon, strain ZY8(T), was isolated from a rock salt of Yunnan salt mine. It was able to grow at 12-30% (w/v) NaCl (optimum, 15-20%), pH 7.0-9.0 (optimum, pH 8.5), and 20-45 degrees C (optimum, 42 degrees C). Sequence similarity search of its 16S rRNA gene showed that strain ZY8(T) belonged to the genus Halorubrum, and it is closely related to species of H. aethiopicum SAH-A6(T) (98.6%), H. aquaticum EN-2(T) (98.6%), and H. halodurans Cb34(T) (98.5%), respectively. Strain ZY8(T) contained phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate as its major phospholipids, and a sulfated diglycosyl diether as its major glycolipid. The DNA G+C content was 66.7mol%. DNA-DNA relatedness between strains ZY8(T) and closely related species were far below 70%. Based on the phenotypic and phylogenetic analyses, it is proposed that strain ZY8(T) represents a novel species of the genus Halorubrum, for which the name Halorubrum glutamatedens sp. nov. is proposed. The type strain is ZY8(T) (=CGMCC 1.16026(T)=NBRC 112866(T)).