Tl. Netzel, PRESENT STATUS AND FUTURE-DIRECTIONS OF RESEARCH IN ELECTRON-TRANSFERMEDIATED BY DNA, JBIC. Journal of biological inorganic chemistry, 3(2), 1998, pp. 210-214
This commentary article presents an overview of recent experimental re
sults on DNA-mediated electron transfer (ET) from the perspective of s
emiclassical ET theory. The question concerning whether or not DNA can
act as a wire is addressed, Much of the article focuses on a discussi
on of the decay of electronic coupling (beta) between electron donors
and accepters with increasing donor/acceptor separation in DNA and in
protein systems. In particular, the dependence of the electronic coupl
ing itself (H-AB) on the energy gap between the tunneling energy of th
e reactants and the virtual ionic states of the DNA bridge is highligh
ted. The article concludes by suggesting that future experimental and
theoretical work in this field should focus on the tunneling gap energ
ies of the systems studied and that special attention should be paid t
o systems that are likely to be in the ''small tunneling gap'' regime.
It is these systems that are expected to exhibit enhanced electronic
couplings and consequently enhanced rates of long-distance ET.