CIRCULAR-DICHROISM, LUMINESCENCE, AND ELECTRONIC ABSORPTION OF COPPER-BINDING SITES IN METALLOTHIONEIN AND ITS CHEMICALLY SYNTHESIZED ALPHA AND BETA DOMAINS

The stoichiometry and molecular architecture of Cu-thionein is unknown. Thus, the oligonuclear copper-binding sites of chemically synthesized alpha and beta fragments employing continuous flow solid phase peptide synthesis technique have been studied and compared with those of the apo-MT, intact Cd5Zn2-MT and its substituted form Cd7-MT. The Cu(I)-binding species can be unambiguously identified as CU6-alpha, CU6-beta, Cd5CU3-MT and Cu12-MT, attributable to their circular dichroism (CD), electronic absorption (UV), and, above all, luminescence emission properties.