Fast Consecutive Intramolecular Processes Involving Protein and Fe(III) in Ferri-Cytochrome-c in Aqueous Solution

The reaction of H atoms (produced by nanosecond pulse radiolysis) with ferri-cytochrome-c in aqueous solution results in the second order formation of an absorption spectrum due to the addition of H atoms to the enzyme protein. This spectrum is not specific to the iron moiety. The rate constant of the addition is 1×10¹⁰M^?1 sec^?1. This is followed by two first order intramolecular processes with specific rates of ～ 1×10⁵ sec^?1 and ～ 2×10⁴ sec^?1. In these processes, specific spectra related to the α and β bands of ferro-cytochrome-c appear. The results are interpreted to show reduction equivalent transfer through the protein to the iron moiety.