Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (01): 73-77.doi: 10.3866/PKU.WHXB20122873


One-Electron Redox Characteristics of One-Hydroxyl Radical Adducts of A-T Base Pairs

HOU Ruo-Bing, SUN Yan-Li, WANG Bei-Bei   

  1. College of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin 541004, Guangxi Province, P. R. China
  • Received:2011-08-01 Revised:2011-10-24 Published:2011-12-29
  • Contact: HOU Ruo-Bing

Abstract: The one-electron redox characteristics of one-hydroxyl radical adducts of adenine-thymine base pairs were calculated using density functional theory at the B3LYP/DZP ++//B3LYP/6-31 ++ G(d,p) level. The computational results indicate that all eight adducts are strong oxidizing agents and very weak reducing agents. For the AC2-T, AC4-T, and AC5-T adducts electron capture causes a hydrogen atom migration from the N3 site of thymine to the N1 site of adenine. The hydrogen atom transfer reactions in the anion adducts are attributable to a higher electron density of the adenine moiety. The higher electron density favors the formation of a new N-H bond on the adenine base.

Key words: Adenine-thymine base pair, Addition reaction, Hydroxyl radical, Electron affinity, One-electron redox