A Model for Light-Driven Proton Pump and Transfer inBacteriorhodopsin

Abstract

A theoretical model was assumed to describe the kinetic processes oflight-driven proton pump and motion. The calculation shows that thephotovoltage signals are greatly affected by experimental conditionsincluding pulse width of excitation and impedance of measurementsystem. At the same excitation, only a negative photovoltage signal canbe observed with small impedance and both the negative and positivesignals can be observed with large impedance. With the same impedance,shorter response time of the pulsed photoelectric signals isresponsible for shorter pulsed excitation. All these phenomena are ingood agreement with the experimental results.