Effect of high pressure on the light-induced structural change of bacteriorhodopsin reconstituted in liposome

Bacteriorhodopsin (BR) is reconstituted into multilamellar phosphatidylcholine vesicles. When this reconstituted bacteriorhodopsin is under high pressure without illumination, a structural transition, in which the absorption maximum of the retinal changes from 560 nm to 500 nm, occurs reversibly. Upon illumination, bacteriorhodopsin reconstituted into vesicles is denatured irreversibly and, under high pressure, a 460-nm absorption peak of the chromophore appears transiently.