Rate constants for the reactions of DNA with hydrated electrons and with OH-radicals

Rate constants for the reaction of double-stranded DNA from calf thymus with hydrated electrons and hydroxyl radicals were determined in different phosphate buffers by pulse radiolysis. The rate constants are shown to be dependent on both the ionic conditions and the DNA-structure. In 10(-2) mol dm(-3) phosphate buffer pH 7, the bimolecular rate constant of non-collapsed DNA with the hydrated electron is 2 x 10(9) dm(3) mol(-1) s(-1). This value is more than 10-fold higher than the previously published value. Considerations of these rate constants on the results of steady-state experiments are also discussed. (c) 2004 Elsevier Ltd. All rights reserved.