Probing ligand binding to duplex DNA using KMnO4 reactions and electrospray ionization tandem mass spectrometry.

ABSTRACT: An electrospray ionization tandem mass spectrometry (ESI-MS/MS) strategy employing the thymine-selective KMnO4 oxidation reaction to detect conformational changes and ligand binding sites in noncovalent DNA/drug complexes is reported. ESI-MS/MS is used to detect specific mass shifts of the DNA ions that are associated with the oxidation of thymines. This KMnO4 oxidation/ESI-MS/MS approach is an alternative to conventional gel-based oxidation methods and affords excellent sensitivity while eliminating the reliance on radiolabeled DNA. Comparison of single-strand versus duplex DNA indicates that the duplexes exhibit a significant resistance to the reaction, thus confirming that the oxidation process is favored for unwound or single-strand regions of DNA. DNA complexes containing different dr

SUBMITTER: Mazzitelli CL 

PROVIDER: S-EPMC2531255 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature