Jeppesen C, Nielsen P E
Department of Biochemistry B, University of Copenhagen, Denmark.
FEBS Lett. 1988 Apr 11;231(1):172-6. doi: 10.1016/0014-5793(88)80725-7.
Binding of the bis-intercalators echinomycin and N,N'-di(9-acridinyl)spermidine or the mono-intercalators 9-aminoacridine and ethidium to DNA induces hypersensitivity of adenines towards reaction with diethyl pyrocarbonate. It is proposed that this hyperreactivity is due to the DNA helix unwinding and extension induced by intercalation, thereby exposing N7 in the major groove, and not as previously suggested to the formation of Hoogsteen base pairing. Hypersensitivity of thymines towards oxidation with permanganate is also induced upon binding of these drugs (especially the bis-intercalators) to DNA. This thymine hyperreactivity is both sequence- and intercalator-dependent, thereby indicating the potential of KMnO4 as a useful probe for analyzing the structure of intercalator-DNA complexes in solution.
双嵌入剂放线菌素和N,N'-二(9-吖啶基)亚精胺或单嵌入剂9-氨基吖啶和溴化乙锭与DNA的结合会诱导腺嘌呤对与焦碳酸二乙酯反应的超敏性。有人提出，这种高反应性是由于嵌入作用诱导DNA螺旋解旋和伸展，从而使大沟中的N7暴露，而不是如先前所认为的形成Hoogsteen碱基对。这些药物（尤其是双嵌入剂）与DNA结合后，也会诱导胸腺嘧啶对高锰酸钾氧化的超敏性。这种胸腺嘧啶高反应性既依赖于序列，也依赖于嵌入剂，从而表明高锰酸钾作为分析溶液中嵌入剂-DNA复合物结构的有用探针的潜力。
