HPLC analysis of disulfide bond formation in duplexes containing the abasic site analog.

(A, B, C, E, and F) Chromatograms of the duplexes, in which X represents the abasic site analog, after the reactions for the indicated length of time. C4 and C3 represent the 4-mercaptobutyl and 3-mercaptopropyl groups, respectively. The y-axis of each chromatogram was normalized. The cross-linked products and the sulfinic acid-containing oligonucleotides are indicated by an arrow and an asterisk, respectively, and the results of the DTT treatment of the products are shown in red. (D) Comparison of the product formation between AP-6 (C4) and AP·A-6 (C4). The product peak areas in panels A and B were quantified.