The Generation of Radicals during the Normal and Abnormal Functioning of Cytochromes P-450
Oxygen exhibits very rich redox chemistry and, as shown in Scheme 1, hemes and hemeproteins play major roles in both the production of and protection from a variety of oxygen and other free radicals. In addition catalase destroys, at a diffusion-controlled rate, hydrogen peroxide by a two-electron process which does not generate hydroxyl radicals. On the other hand hydrogen peroxide, along with a wide variety of transition metal ions, is the principal source of in vivo hydroxyl radicals.
KeywordsCation Radical Veratryl Alcohol Iron Porphyrin Peroxy Acid Ferric Heme
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