Studies On 16S RDNA Sequence And Bacteriorhodopsin Encoding Gene Of Halophilic Archaea From Dabancheng Saline Lake In Xin Jiang

Halophilic archaea had been isolated from various hypersaline environments.Bacteriorhodopsin (BR) is a retinal-binding membrane protein with seven membrane-spanning segments and functions as a light-driven proton pump in halophilic archaea.And BR protein has great development trend and application value. In this dissertation, we reviewed the development of halophilic archaea, and the structure, function and application of BR protein. Our research focused on the taxonomy of the halobacterial strains isolated from the samples of Da Bancheng saline lake in Xin Jiang , and the attaining ,the analysis on BR protein gene fragment. In the research, sixteen strains were isolated. All of them are Gram-negative including pleomorphic and occoid types.The results of homology and phylognetic analysis on 16S rDNA gene show that the strains isolated belong to four genera as following, Natrialba,Haloarcula,Haloterrigena,Halorubrum.The haloalkaliphilic archaeon isolated belong to the genera Natrialba and was considered the main group of haloalkaliphilic archaeon in the lake.Partial DNA fragments encoding BR protein from strain 205 were amplified by polymerase chain reaction(PCR). The results indicate that compared to the deduced amino acid sequences of other existing BRs, BR protein of 205 is obviously different to others.And the 205 BR protein is DR type from phylognetic analysis on the BR gene amplified.