5,6-Dihydropyrimidine peroxyl radical reactivity in DNA. Academic Article uri icon

abstract

  • Nucleobase radicals are a major family of reactive species produced in DNA as a result of oxidative stress. Two such radicals, 5-hydroxy-5,6-dihydrothymidin-6-yl radical (1) and 5,6-dihydrouridin-6-yl radical (5), were independently generated within chemically synthesized oligonucleotides from photochemical precursors. Neither nucleobase radical produces direct strand breaks or alkali-labile lesions in single or double stranded DNA. The respective peroxyl radicals, resulting from O2 trapping, add to 5'-adjacent nucleobases, with a preference for dG. Distal dG's are also oxidatively damaged by the peroxyl radicals. Experiments using a variety of sequences indicate that distal damage occurs via covalent modification of the 5'-adjacent dG, but there is no evidence for electron transfer by the nucleobase peroxyl radicals.

published proceedings

  • J Am Chem Soc

author list (cited authors)

  • San Pedro, J., & Greenberg, M. M.

citation count

  • 28

complete list of authors

  • San Pedro, Joanna Maria N||Greenberg, Marc M

publication date

  • January 2014