Isolating Two Native Extreme Halophilic Bacterial Strains Producing Bacteriorhodopsin Protein from Aran-Bidgol Lake

Document Type : Original Article


Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran


Bacteriorhodopsin operates as a light/proton transfer pump which converts the light energy into a proton gradient. The energy stored in the proton gradient can be used in a variety of ways. The main source of Bacteriorhodopsin are some Halobacterium species such as Halobacterium sodomense and Halobacterium salinarum which grow in harsh and salt-saturated conditions. In order to isolate strains from Aran-Bidgol Lake, two red pigment (IRLS.1) and orange pigment (IRLS.2) strains were isolated. Spectroscopy reviews and the results of SDS-Page of membrane proteins of two isolated strains as well as Iranian native Halobacterium salinarum showed that bacteriorhodopsin protein presents in the collected sample. Spectroscopic studies showed that Halobacterium salinarum produces the maximum amount than IRLS.1 and IRLS.2 produces less and lesser amount of bacteriorhodopsin respectively. The results of biochemical and molecular identification based on the 16srRNA of both mentioned strains indicated their highest similarity with Natrinema sp. XA3-1 and Archaeon RC34, respectively. In this study, the presence of bacteriorhodopsin protein in Iranian native strains was examined for the first time and the local strains were isolated purely from Halobacterium salinarum membrane by gel filtration chromatography that given the widespread use of bacteriorhodopsin protein, it will be so effective.