The photocycle of the chloride pump halorhodopsin. II: Quantum yields and a kinetic model

Abstract
The quantum yield of the primary photoreaction of HR578 was determined as øgreen = 0.34±0.02 and that of the photochemical reconversion of HRL410 into HR578 as øblue = 0.01±0.004. From steady‐state illumination and flash‐photolysis experiments, a quantitative description of HRL410 formation and decay was made leading to a model of the photocycle in isolated, light‐adapted HR. This model satisfies all known facts about HR including its photochromic behaviour.