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Radiation-induced formation of 2',3'-dideoxyribonucleosides in DNA: a potential signature of low-energy electrons.

ABSTRACT: We have identified a series of modifications of the 2'-deoxyribose moiety of DNA arising from the exposure of isolated and cellular DNA to ionizing radiation. The modifications consist of 2',3'-dideoxyribonucleoside derivatives of T, C, A, and G, as identified by enzymatic digestion and LC-MS/MS. Under dry conditions, the yield of these products was 6- to 44-fold lower than the yield of 8-oxo-7,8-dihydroguanine. We propose that 2',3'-dideoxyribonucleosides are generated from the reaction of low-energy electrons with DNA, leading to cleavage of the C3'-O bond and formation of the corresponding C3'-deoxyribose radical.

SUBMITTER: Madugundu GS

PROVIDER: S-EPMC3818160 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Radiation-induced formation of 2',3'-dideoxyribonucleosides in DNA: a potential signature of low-energy electrons.

Madugundu Guru S GS Park Yeunsoo Y Sanche Léon L Wagner J Richard JR

Journal of the American Chemical Society 20121015 42

We have identified a series of modifications of the 2'-deoxyribose moiety of DNA arising from the exposure of isolated and cellular DNA to ionizing radiation. The modifications consist of 2',3'-dideoxyribonucleoside derivatives of T, C, A, and G, as identified by enzymatic digestion and LC-MS/MS. Under dry conditions, the yield of these products was 6- to 44-fold lower than the yield of 8-oxo-7,8-dihydroguanine. We propose that 2',3'-dideoxyribonucleosides are generated from the reaction of low- ...[more]

PMID: 23057636

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