Evidence for glycosidic bond rotation in a nucleobase peroxyl radical and its effect on tandem lesion formation

被引：27

作者：

Hong, IS ^{[1
]}

Carter, KN ^{[1
]}

Greenberg, MM ^{[1
]}

机构：

[1] Johns Hopkins Univ, Dept Chem, Baltimore, MD 21218 USA

来源：

JOURNAL OF ORGANIC CHEMISTRY | 2004年 / 69卷 / 21期

关键词：

D O I：

10.1021/jo0492158

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Nucleobase peroxyl radicals are the major reactive intermediates formed in DNA when the biopolymer is exposed to gamma-radiolysis under aerobic conditions. The major reaction pathways for the peroxyl radical (1) derived from 5,6-dihydro-2'-deoxyuridin-6-yl involve pi-bond addition to or hydrogen atom abstraction from the adjacent nucleotides to produce tandem lesions. The ability to independently generate 1 at a defined site in DNA enabled us to probe its reactivity by varying the local DNA structure. The effect of DNA structure variation reveals that 1 reacts from its syn- and anti-conformations in competition with trapping by thiol. These experiments also reveal that tandem lesions will be produced as a mixture of diastereomers, which could impact their biological effects.

引用

页码：6974 / 6978

页数：5

共 38 条

[1] Cross-linked thymine-purine base tandem lesions:: Synthesis, characterization, and measurement in γ-irradiated isolated DNA [J].