Two-photon absorption of bacteriorhodopsin: formation of a red-shifted thermally stable photoproduct F620.


By means of high-intensity 532 nm laser pulses, a photochemical conversion of the initial B(570) state of bacteriorhodopsin (BR) to a stable photoproduct absorbing maximally at approximately 620 nm in BR suspensions and at approximately 610 nm in BR films is induced. This state, which we named F(620), is photochemically further converted to a group of three… (More)