Cd-, Zn-, Cu-binding protein in the elasmobranch Scyliorhinus canicula

A Cd-, Zn-, Cu-binding protein was isolated from the liver of dogfish subjected to environmental experimental contamination (50 ppm Cd). It was also found in liver from untreated fish. This protein has a high absorption at 250 nm and a low absorption at 280 nm, suggesting a mercaptide bond and a lack of aromatic amino acids. The SDS-PAGE pattern and changes in absorption spectrum on adding Cd or lowering pH are found as for mouse MT. The protein contains Cu and Zn in control and Cu, Zn and Cd in treated fish. Cd levels in the protein are significantly higher in females and significantly increase with treatment duration. Copper levels decrease after 96 hr in males and 6 days in females.