title: Reduction of ferricytochrome c by some free radical agents.
abstract: Fast pulse radiolysis and kinetic spectroscopy were used to rapidly generate a variety of free radicals in situ and study their reactions with ferricytochrome c in the time range 10(-6) to 1 second. The radicals included t-butanol, which is inert to ferricytochrome c; malate, lactate, and ethanol, which react with it relatively slowly but are completely utilized in reducing it to ferrocytochrome c; and hydrated electrons and hydrogen atoms, which react with it very rapidly but yield ferrocytochrome c only in part, showing intramolecular consecutive reactions and further attack on the ferrocytochrome c protein. From a detailed comparison between malate and hydrogen atoms it is argued that malate reacts directly and selectively with a specific part of the ferricytochrome c surface while hydrogen atoms react with other parts of the protein too, yielding radicals which in part transfer intramolecularly to yield ferrocytochrome c.
mesh_terms: D000440:Butanols; D003574:Cytochrome c Group; D000431:Ethanol; D005609:Free Radicals; D007501:Iron; D007773:Lactates; D008293:Malates; D010084:Oxidation-Reduction; D011830:Radiation Effects; D013057:Spectrum Analysis
chemical_list: D000440:Butanols; D003574:Cytochrome c Group; D005609:Free Radicals; D007773:Lactates; D008293:Malates; D000431:Ethanol; D007501:Iron