Addressing the competitive formation of tandem DNA lesions by a nucleobase peroxyl radical: a DFT-D screening

作者：Dupont C; Patel C; Ravanat J L; Dumont E^*

来源：Organic and Biomolecular Chemistry, 2013, 11(18): 3038-3045.

DOI：10.1039/c3ob40280k

The presence of two vicinal single-nucleotide oxidative lesions constitutes a pitfall case for DNA repair. Quantum mechanics calculations are performed to elucidate the formation of peroxyl-bridged adducts, where a purine and a pyrimidine base become covalently tethered. A dispersion-corrected density functional theory (DFT-D) screening along the 32 possible adducts built by a combination of the four different nucleobases outlines that guanine is a better tandem partner than adenine, in line with experimental data. In contrast, cytosine and thymine have an overall comparable reactivity as revealed by a highly localized spin density. For a given purine and pyrimidine combination, our computational approach also sketches some differences concerning the syn vs. anti configurations and the orientation strand.

• 出版日期2013
• 单位中国地震局