Excitation of the M intermediates of bacteriorhodopsin

摘要: Protein electric response signals (PERS) of the M intermediates wild-type bacteriorhodopsin (bR) were recorded. Contrary to earlier findings reporting on a single-phase upon excitation intermediates, kinetic analysis revealed existence three components, fastest and slowest ones negative, while middle one positive sign with respect normal direction proton pumping. Based motion indicator experiments molecular dipole calculations, components assigned transfer steps conformational changes driving bR molecule back from ground state blue light excitation. The fastest, negative pump component was D85 Schiff base. subsequent attributed rearrangements in protein core (in vicinity retinal molecule), triggered by primary process. established reflect charge associated uptake bulk.