Natrialba hulunbeirensis sp nov and Natrialba chahannaoensis sp nov., novel haloalkaliphilic archaea from soda lakes in Inner Mongolia Autonomous Region, China

Two haloalkaliphilic archaeal strains, X21(T) and C112(T), were isolated fr om soda lakes in Inner Mongolia Autonomous Region, China. Their morphology, physiology, biochemical features, polar lipid composition and 16S rRNA gen es were characterized in order to elucidate their taxonomy. According to th ese data, strains X21T and C112(T) belong to the genus Natrialba, although there are clear differences with respect to their physiology and polar lipi d composition between the two strains and the type species, Natrialba asiat ica. On the basis of low DNA-DNA hybridizations, these two strains should b e considered as new species of genus Natrialba. The names Natrialba hulunbe irensis sp. nov. (type strain X21(T) = AS 1.1986(T) = JCM 10989(T)) and Nat rialba chahannaoensis sp. nov. (type strain C112(T) = AS 1.1977(T) = JCM 10 990(T)) are proposed.