THE MECHANISM OF SEPARATION OF POLYTHIOLPEPTIDES AND METALLOPOLYTHIOLPEPTIDES BY COVALENT AFFINITY-CHROMATOGRAPHY

Covalent affinity chromatography with thiol-disulphide interchange (CA D-TDI) is a method for the separation of thiolproteins based on the in teraction between disulphide bridges immobilised on a insoluble suppor t and thiol groups in the protein undergoing separation. Mercury-thion ein, cadmium-thionein and apothionein have been used as low molecular weight thiolproteins rich in cysteine residue. The proposed separation mechanism is more complex than those in the literature and can have a nionic, cationic or a free radical character depending on the protein, the ligand and the conditions during separation.