A CONFORMATIONAL CHANGE OF BACTERIORHODOPSIN CAUSED BY PAPAIN DIGESTION
酶切菌紫质C端引起的紫膜蛋白的发光性质变化

Bacteriorhodopsin shows an unnormal fluorescence emission after removing the C-terminal region by papain digestion in low concentration. The Trp fluorescence intensity is enhanced and shows a red shift at high salt concentrtion of KC1. The quenching effect of Cs+ on Trp fluorescence suggests that some Trp residues have exposed to the medium. The increasing intensity of phosphorescence emission of papain-treated bR indicates also the Trp exposure to the medium. The possible effect of the conformational change on proton pumping is discussed.