Ab initio molecular orbital study on the G-selectivity of GGG triplet in copper(I)-mediated one-electron oxidation.
The G-selectivity for Cu(I)-mediated one-electron oxidation of 5'-TG(1)G(2)G(3)-3' and 5'-CG(1)G(2)G(3)-3' has been examined by ab initio molecular orbital calculations. It was confirmed that G(1) is selectively damaged by Cu(I) ion for both 5'-TG(1)G(2)G(3)-3' and 5'-CG(1)G(2)G(3)-3', being good agreement with experimental results. The Cu(I)-mediated G(1)-selectivity is primarily due to the stability of the Cu(I)-coordinated complex, [-XG(1)G(2)G(3)-,-Cu(I)(H(2)O)(3)](+). The Cu(I) ion coordinates selectively to N7 of G(2) of 5'-G(1)G(2)G(3)-3' rather than N7 of G(1). The G(2)-selective coordination induces the G(1)-selective trap of a hole that is created by one-electron oxidation and migrates to GGG triplet. Therefore, the radical cation of G(1) is selectively created in both 5'-TG(1)G(2)G(3)-3' and 5'-CG(1)G(2)G(3)-3', giving the G(1)-selective damage of 5'-G(1)G(2)G(3)-3'.
Yoshioka
Yasunori
Y
Chemistry Department for Materials, Faculty of Engineering, Mie University, Tsu, Mie 514-8507, Japan. yyoshi@chem.mie-u.ac.jp
Kawai
Hiroko
H
Sato
Tomoko
T
Yamaguchi
Kizashi
K
Saito
Isao
I
D002414:Cations, Monovalent; D003300:Copper / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D004249:DNA Damage; D006147:Guanine / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D009841:Oligonucleotides / Q000737:chemistry*; D010084:Oxidation-Reduction
D002414:Cations, Monovalent; D009841:Oligonucleotides; D006147:Guanine; D003300:Copper; D004247:DNA