Culturable halophilic archaeal diversity of Ayakekumu salt lake located in Xinjiang, China

Molecular diversity of halophilic archaea from Ayakekumu salt lake was investigated by the polymerase chain reaction (PCR) amplification and culture methods. 19 water samples and 15 soil samples were taken from 19 sites within Ayakekumu salt lake in winter and spring. Under aerobic culture conditions, some halophilic microorganisms were isolated by five different media. The 16S rRNA gene sequences of 62 red strains were amplified by using PCR, determined by the DNA sequencer and analyzed through the BLASTn program subsequently. Results revealed that all sequences belonged to six genera grouped within the Halobacteriaceae. Mostly 16S rRNA gene sequences related to the genera Halorubrum (47%) and Natrinema (24%) were detected. Subsequent analysis by using Shannon index indicated that cultured halophilic archaeal diversities are not significantly different between winter and spring samplings in Ayakekumu salt lake. Similarity values of haloarchaeal 16S rRNA gene sequences to known sequences were less than 97%, suggesting the presence of two novel taxa. In addition, taxonomic characteristics of Natrinema altunense and Halobiforma lacisalsi isolated from Ayakekumu salt lake had been described previously. The discovery of the novel species provides new opportunity to further examine the diversity of these halophilic microorganisms in Ayakekumu salt lake.