A PLAUSIBLE CONTRIBUTION OF POLARON EXCITATIONS TO ELECTRON-TRANSFER THROUGH LARGE DISTANCES IN GLOBULAR-PROTEINS

The rate of electron transfer through various types of polaron states is calculated for self-exchange reactions in globular proteins. It is shown that, if the difference between the energies of an electron in a donor molecule and of polaron excitation does not exceed 1 eV, the el ectron transfer via the ground is polaron state dominates over the dir ect electron transfer from the donor to an acceptor. Transfer via othe r highly excited polaron states is unlikely. The dependence of the tra nsfer rate on the donor-acceptor separation is governed by the polaron mechanism and is characterized by parameter beta similar to 1 h(-1).