Formation of cross-linked adducts between guanine and thymine mediated by hydroxyl radical and one-electron oxidation: a theoretical study.
The role of local geometric and stereo-electronic effects in tuning the preference for different cross-linked adducts between thymine and purinic bases has been analyzed by a computational approach rooted in density functional theory. Our study points out that G--T and T--G tandem lesions are produced according to the same mechanism as A--T and T--A intrastrand adducts, and in both cases purine--T adducts are preferred rather than the opposite sequences. Moreover, use of conceptual DFT tools allows the rationalization of the preferential occurrence of G--T and T--G tandem lesions in place of their A--T and T--A counterparts.
Labet
Vanessa
V
Laboratoire Lésions des Acides Nucléiques, INAC/SCIB, UMR-E 3 (CEA/UJF), CEA-Grenoble, 17 rue des Martyrs, 38054, Grenoble cedex 9, France.
Morell
Christophe
C
Grand
André
A
Cadet
Jean
J
Cimino
Paola
P
Barone
Vincenzo
V
D004583:Electrons; D005740:Gases / Q000737:chemistry; D006147:Guanine / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry*; D007700:Kinetics; D008958:Models, Molecular; D015394:Molecular Structure; D010084:Oxidation-Reduction; D013816:Thermodynamics; D013941:Thymine / Q000737:chemistry*
D005740:Gases; D017665:Hydroxyl Radical; D006147:Guanine; D013941:Thymine