Studies on the Mechanism of Action of Azinomycin B: Definition of Regioselectivity and Sequence Selectivity of DNA Cross-Link Formation and Clarification of the Role of the Naphthoate
作者:Robert S. Coleman、Ronelito J. Perez、Christopher H. Burk、Antonio Navarro
DOI:10.1021/ja025563k
日期:2002.11.1
Evaluation of the sequence selectivity, noncovalent association, and orientation of the DNA cross-linking agent azinomycin B on its duplex DNA receptor is described. A strong correlation between sequence nucleophilicity and cross-linking yield was observed, and steric effects due to the thymine C5-methyl group were identified. Detailed studies on the role of the azinomycin naphthoate using viscometry, fluorescence contact energy transfer, and DNA unwinding assays point to a nonintercalative binding mode for this group. A kinetic assay for agent regioselectivity was used to determine the orientation of binding and covalent cross-link formation.