Pulse radiolysis studies on histones and serum albumin under different ionic conditions

Rate constants of bovine serum albumin (BSA) and histones for their reactio ns with the hydrated electrons and the OH-radicals were determined in diffe rent phosphate buffers and in water by pulse radiolysis. The rate constants of histones change considerably with the ionic strength and with the pH, w hile different phosphate concentrations do not change these reaction rates of BSA. The results indicate that the rate constants are independent of the contents of highly reactive amino acid residues, but dependent on the rati o of surface : volume. (C) 2001 Elsevier Science Ltd. All rights reserved.