A novel method for determining the electron tunneling pathway in protein is
proposed. The pathway is constructed connecting vectors of important inter
atomic currents of the tunneling electron. The method is applied to some ru
thenium-modified azurins. From this analysis, we found that the through-spa
ce is very often used as well as the through-bond, while the hydrogen-bond
is scarcely used in the important interatomic currents. (C) 2000 Elsevier S
cience S.A. All rights reserved.