Which protein plays a key role as a major copper transport molecule and migrates with the alpha2 globulins?

Which protein plays a key role as a major copper transport molecule and migrates with the alpha2 globulins?

• A. Ceruloplasmin
• B. Haptoglobin
• C. Transferrin
• D. Fibrinogen

Answer: (A)

Ceruloplasmin is the major copper transport protein in the bloodstream. It binds the vast majority of circulating copper and is produced by the liver. In addition to its copper-binding role, it acts as a ferroxidase, converting Fe2+ to Fe3+ so iron can be bound by transferrin, linking copper metabolism to iron transport. Its high copper content and its physical properties cause it to migrate with the alpha-2 globulins during serum protein electrophoresis. That electrophoretic position helps distinguish it from other proteins with different functions and migration patterns. The other proteins listed have different primary roles: haptoglobin binds free hemoglobin, transferrin carries iron (a beta-globulin), and fibrinogen is a clotting factor not typically associated with copper transport. Thus, the protein that fits both the copper transport function and the alpha-2 globulin migration is ceruloplasmin.

Ceruloplasmin is the major copper transport protein in the bloodstream. It binds the vast majority of circulating copper and is produced by the liver. In addition to its copper-binding role, it acts as a ferroxidase, converting Fe2+ to Fe3+ so iron can be bound by transferrin, linking copper metabolism to iron transport.

Its high copper content and its physical properties cause it to migrate with the alpha-2 globulins during serum protein electrophoresis. That electrophoretic position helps distinguish it from other proteins with different functions and migration patterns.

The other proteins listed have different primary roles: haptoglobin binds free hemoglobin, transferrin carries iron (a beta-globulin), and fibrinogen is a clotting factor not typically associated with copper transport. Thus, the protein that fits both the copper transport function and the alpha-2 globulin migration is ceruloplasmin.