THE HAEMPEPTIDES FROM CYTOCHROME-C - EXPLORING THE BASIC CHEMISTRY OFTHE IRON PORPHYRINS AND MODELING ASPECTS OF THE HEMOPROTEINS

The haempeptides from cytochrome c, obtained by proteolysis of the par ent protein, contain an iron(lll) porphyrin linked by thioether bridge s to a polypeptide chain. They provide an opportunity for exploring as pects of the fundamental chemistry of an iron(III) porphyrin in which one of the axial coordination sites of the metal ion is occupied by a His residue (from the parent protein) and the other contains a readily -replaced H2O molecule. The preparation, solution properties and elect ronic properties of these important models for the haemoproteins are r eviewed and facets of their reactions are considered.