Haloterrigena hispanica sp nov., an extremely halophilic archaeon from Fuente de Piedra, southern Spain

An extremely halophilic archaeon belonging to the order Halobacteriales was isolated from Fuente de Piedra salt lake, Spain. This strain, designated FP1(T), was a pleomorphic coccoid, neutrophilic and required at least 15 % (w/v) NaCl for growth. Strain FP1(T) grew at 37-60 degrees C, with optimal growth at 50 degrees C. Mg2+ was not required, but growth was observed with up to 10 % (w/v) MgSO4. Polar lipid analysis revealed the presence of mannose-6-sulfate(1-2)-glucose glycerol diether as a major glycolipid. Both C20C20 and C20C25 core lipids were present. The genomic DNA G + C content was 62.0 mol%. Phylogenetic analysis based on comparison of 16S rRNA gene sequences demonstrated that the isolate was most closely related to species of the genus Haloterrigena. DNA-DNA reassociation values between strain FP1(T) and the most closely related species of the genus Haloterrigena (Haloterrigena thermotolerans, Haloterrigena saccharevitans and Haloterrigena limicola) were lower than 29 %. It is therefore considered that strain FP1(T) represents a novel species of the genus Haloterrigena, for which the name Haloterrigena hispanica sp. nov. is proposed. The type strain is FP1(T) (=DSM 18328(T) =ATCC BAA-11310(T)).