TY - JOUR
T1 - Transport and reactions of radical cations in DNA
T2 - Steric and energetic control of reactivity
AU - Abdou, Ibrahim M.
AU - Boone, Edna K.
AU - Cao, Huachuan
AU - Crummie, Cheryl
AU - Schuster, Gary B.
PY - 2004
Y1 - 2004
N2 - A series of DNA oligomers was prepared that contain an anthraquinone group (AQ) linked to a 5'-terminus and have 8-methylguanine (MG) or 8-bromoguainine (BG) substituted for G at various positions. Irradiation of the AQ injects a radical cation into the oligonucleotide, which migrates through the DNA and reacts primarily at Gn sites where n = 2 or 3. Substitution with MG which has an oxidation potential (E OX) slightly below G, traps the migrating radical cation, substitution with BG, which has an EOX above G, does not. However, both MG and BG affect the relative reactivity of the guanines in Gn steps. Moreover, a (G)3 sequence has a much smaller effect on the efficiency of radical cation migration than does MG, which demonstrates that the EOX of G in the (G) 3 sequence is above that of MG. These findings show that the EOX of the base controls the efficiency of radical cation transport and that steric effects influence the relative reactivity of G in Gn sequences.
AB - A series of DNA oligomers was prepared that contain an anthraquinone group (AQ) linked to a 5'-terminus and have 8-methylguanine (MG) or 8-bromoguainine (BG) substituted for G at various positions. Irradiation of the AQ injects a radical cation into the oligonucleotide, which migrates through the DNA and reacts primarily at Gn sites where n = 2 or 3. Substitution with MG which has an oxidation potential (E OX) slightly below G, traps the migrating radical cation, substitution with BG, which has an EOX above G, does not. However, both MG and BG affect the relative reactivity of the guanines in Gn steps. Moreover, a (G)3 sequence has a much smaller effect on the efficiency of radical cation migration than does MG, which demonstrates that the EOX of G in the (G) 3 sequence is above that of MG. These findings show that the EOX of the base controls the efficiency of radical cation transport and that steric effects influence the relative reactivity of G in Gn sequences.
KW - Duplex irradiation
KW - Energetic control
KW - Radical cations
KW - Steric control
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U2 - 10.1163/1568567041257562
DO - 10.1163/1568567041257562
M3 - Article
AN - SCOPUS:3142674845
SN - 0922-6168
VL - 30
SP - 419
EP - 427
JO - Research on Chemical Intermediates
JF - Research on Chemical Intermediates
IS - 4-5
ER -