Superexchange coupling and electron transfer in globular proteins via polaron excitations.
The polaron approach is used to treat long-range electron transfersbetween globular proteins. A rate expression for the polaron transfer model is given along with a description of appropriate conditions forits use. Assuming that electrons transfer via a superexchange couplingdue to a polaron excitation, we have estimated the distance dependenceof the rate constant for the self-exchange reactions between globularproteins in solutions. The distance dependence of the polaron coupling andsolvent reorganization energy are provided as a basis forunderstanding and interpreting a long-range electron transfer experiment.The difficulties and problems of the polaron treatment of long-rangeelectron transfers are discussed, and suggestions for new experimentsare made.
Institute of Mathematical Problems of Biology, Russian Academy of Sciences, Pushchino, Moscow Region 142292.
G N
GN
Chuev
V D
VD
Lakhno
M N
MN
Ustitnin
Cytochrome; electron transfer; excited transition state; globular protein; polaron; superexchange coupling