Halorussus rarus gen. nov., sp. nov., a new member of the family Halobacteriaceae isolated from a marine solar saltern

Two halophilic archaeal strains TBN4(T) and TBN5 were isolated from Taibei marine solar saltern in Jiangsu China Both strains showed light red-pigmented colonies and their cells were rod, motile and Gram-stain-negative They were able to grow at 25-50 degrees C (optimum 37 degrees C) at 1 4-4 3 MNaCl (optimum 2 1 M NaCl), at 0-1 0 M MgCl2 (optimum 0 005 M MgCl2) and at pH 6 0-9 0 (optimum pH 7 0) Their cells lyse in distilled water and minimal NaCl concentration to prevent cell lysis is 8% (w/v) The major polar lipids of the two strains were PG (phosphatidylglycerol), PGP-Me (phosphatidylglycerol phosphate methylester), PGS (phosphatidylglycerol sulfate) and five glycolipids chromatographically identical to S-TGD-1 (sulfated galactosyl mannosyl glucosyl diether), S-DGD-1 (sulfated mannosyl glucosyl diether), TGD-1 (galactosyl mannosyl glucosyl diether), DGD-1 (mannosyl glucosyl diether) and DGD-2 (an unknown diglycosyl diether) Phylogenetic analysis revealed that TBN4(T) and strain TBN5 formed a distinct clade with genus Haladaptatus (showing 90 0-90 9% 16S rRNA gene similarities) The DNA G + C content of strain TBN4(T) and strain TBN5 are 66 1 and 65 4 mol%, respectively The DNA-DNA hybridization value between strain TBN4(T) and strain TBN5 was 94 3% The phenotypic chemotaxonomic and phylogenetic properties suggest that strain TBN4(T) and strain TBN5 represent a novel species in a new genus within the family Halobacteriaceae, for which the name Halorussus rarus gen nov, sp nov is proposed The type strain is TBN4(T) (=CGMCC 1 10122(T) = JCM 16429(T))