Solubilization and structural stability of bacteriorhodopsin with a mild nonionic detergent, n-Octyl-β-thioglucoside.

Solubilization and structural stability of a membrane protein bacteriorhodopsin (bR) with n-octyl-β-thioglucoside (OTG) was investigated in comparison with a previous study on bR solubilized with n-octyl-β-glucoside (OG). Highly efficient and stable solubilization of bR with OTG was accomplished above the OTG concentration of about 15 mM. In comparison with OG-solubilized bR, the structural stability of OTG-solubilized bR was high in the dark and under light illumination. These results indicate that OTG is a detergent superior to OG for solubilizing bR molecules.