Fibrinogen (FI)
A key protein involved in the coagulation process that circulates in the blood as a soluble dimeric molecule consisting of three-pairs of disulfide-bonded polypeptide chains (Aa, Bb, and g). Fibrinogen serves as the substrate for the enzyme Thrombin. Thrombin cleavage results in the release of fibrinopeptides A & B and fibrin monomer formation. Subsequent noncovalent assembly of fibrin monomers and covalent stabilization by FXIIIa gives rise to a stabilized, insoluble fibrin mesh.
Assay for fibrinogen concentration measured by the rate at which Fibrinogen is converted to fibrin by the action of Thrombin.