Reactions of Dioxygen and Its Reduced Forms with Heme Proteins and Model Porphyrin Complexes

摘要: Among the many kinds of biological complexes transition metals that interact with dioxygen or its variously reduced forms, heme proteins are most common and studied. With only a few exceptions, globular which sequester spatially isolate active porphyrin-iron complex, protoheme (the iron(II) form) protohemin iron(III) form; Figure 3–1). The iron porphyrin is tightly bound to protein through numerous hydrophobic interactions by single coordinate bond between base from so-called proximal amino acid residue, such as an imidazole nitrogen histidine phenolate tyrosine, atom. This shown in 3–2, where B represents base. Dioxygen other small molecules bind opposite (distal) side porphyrin.