TY - JOUR
T1 - Long-distance charge transport in duplex DNA
T2 - The phonon-assisted polaron-like hopping mechanism
AU - Henderson, Paul
AU - Jones, Denise
AU - Hampikian, Gregory
AU - Kan, Yongzhi
AU - Schuster, Gary B.
PY - 1999/7/20
Y1 - 1999/7/20
N2 - An anthraquinone-linked duplex DNA oligomer containing 60 base pairs was synthesized by PCR. The strand complementary to the quinone-containing strand has four isolated GG steps, which serve as traps for a migrating radical cation. Irradiation of the quinone leads to electron transfer from the DNA to the quinone forming the anthraquinone radical anion and a base radical cation. The radical cation migrates through the DNA, causing reaction at GG steps revealed as strand breaks. The efficiency of strand cleavage falls off exponentially with distance from the quinone (slope = -0.02 Å-1). This finding necessitates reinterpretation of mechanisms proposed for radical cation migration in DNA. We propose that radical cations form self-trapped polarons that migrate by thermally activated hopping.
AB - An anthraquinone-linked duplex DNA oligomer containing 60 base pairs was synthesized by PCR. The strand complementary to the quinone-containing strand has four isolated GG steps, which serve as traps for a migrating radical cation. Irradiation of the quinone leads to electron transfer from the DNA to the quinone forming the anthraquinone radical anion and a base radical cation. The radical cation migrates through the DNA, causing reaction at GG steps revealed as strand breaks. The efficiency of strand cleavage falls off exponentially with distance from the quinone (slope = -0.02 Å-1). This finding necessitates reinterpretation of mechanisms proposed for radical cation migration in DNA. We propose that radical cations form self-trapped polarons that migrate by thermally activated hopping.
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U2 - 10.1073/pnas.96.15.8353
DO - 10.1073/pnas.96.15.8353
M3 - Article
C2 - 10411879
AN - SCOPUS:0033587765
VL - 96
SP - 8353
EP - 8358
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 15
ER -