title: The semisynthesis of analogues of cytochrome c. Modifications of arginine residues 38 and 91.
abstract: The arginine residues at positions 38 and 91 of horse cytochrome c are absolutely conserved throughout eukaryotic evolution. For studies of the functional roles of these residues, we have prepared, by semisynthetic techniques, analogues of cytochrome c in which one or the other of the arginine residues has been modified. The products of modification by adduct formation with pentane-2,4-dione were purified and extensively characterized. In biological tests, the arginine-91-modified cytochrome c showed little difference in behaviour from native horse cytochrome c. Modification of arginine-38, however, led to extensive changes in biological and chemical properties. We also prepared and tested adducts with cyclohexane-1,2-dione and camphorquinone-10-sulphonic acid. The same effects on biological properties were noted irrespective of the nature of the modifying group. We suggest reasons for the differences in sensitivity of the two sites.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001120:Arginine / Q000032:analysis; D002850:Chromatography, Gel; D003574:Cytochrome c Group / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism; D010084:Oxidation-Reduction; D010446:Peptide Fragments / Q000032:analysis; D013055:Spectrophotometry, Infrared
chemical_list: D000596:Amino Acids; D003574:Cytochrome c Group; D010446:Peptide Fragments; D001120:Arginine