Regular paper 5’,8-Cyclo-2’-deoxyadenosine (cdA) formation by γ-radiation. Theoretical quantum mechanics study
نویسندگان
چکیده
Reactions of reactive oxygen species and more specifically — of hydroxyl radical (•OH) — with nucleosides may lead to the generation of radicals in the base and 2-deoxyribose moieties. In the present study emphasis was put on the possible reaction modes of 2'-deoxyadenosine (dA) radicals, leading to the formation of related 5’,8-cyclonucleosides. It appears that the prerequisite for the formation of 5’,8-cyclo-2’-deoxyadenosine (cdA) is the adoption of O4’-exo conformation by 2-deoxyribose; however, this is the least energetically favored conformer among the different puckered forms adopted by the furanose ring. The O4’-exo conformation was found to be present in each of the discussed mechanisms.
منابع مشابه
Radiation-induced formation of purine lesions in single and double stranded DNA: revised quantification
The formation of oxidative lesions arising from double stranded DNA damage is of major significance to chemical biology from the perspective of application to human health. The quantification of purine lesions arising from γ-radiation-induced hydroxyl radicals (HO(•)) has been the subject of numerous studies, with discrepancies on the measured 5',8-cyclo-2'-deoxyadenosine (cdA) and 5',8-cyclo-2...
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