Evidence from FTIR-Measurements for a Separation of the Protonated Schiff Base from the Counterion into a Less Polar Environment

The chromoprotein Bacteriorhodopsin transducer light-energy into electrochemical energy by a light-driven protontransfer across the membrane 1). In order to elucidate the proton pump mechanism in molecular detail, we investigated the photocycle with low-temperature FTIR Difference-Spectroscopy