Mechanism of proton transfer in bacteriorhodopsin

Photoinduced proton pumping in bateriorhodopsin (bR) was extensively studied using multiple experimental methods and utilizing various theoretical modelling approaches. These studies usually refer to the well-resolved structural data of bacteriorhodopsin. However, despite obtained results, origin force initiated by electronic excitation retinal remains questionable. Using quantum chemical calculations, we have revealed that molecule after its is fixed ground state 13- cis ,15- syn configuration, as a result interaction with specific protein residuals. Reaching this first transferred aspartic acid No. 85 (Asp-85) residue from water molecule, which subsequently restored initially located Schiff base. We discuss challenges approaches transfer bR demonstrate process, starts mainly due detailed arrangement environment.