Reactivities of Enzymes toward Hydroxyl Radicals

Rate constants of enzyme proteins with hydroxyl radicals were estimated by summation of rate constants of amino acids toward hydroxyl radicals on the assumption that the radical reacts only with amino acid residues located on surface of an enzyme molecule. Kinetic basis of the assumption was discussed in terms of reaction in solution. The calculated rate constants for lysozyme, cytochrome c, ribonuclease, and or-chymotrypsin were found to be consistent with the experimentally obtained ones. © 1974 Oxford University Press. All rights reserved.