Plasminogen (Plg)

Plasmin is an important enzyme (EC 3.4.21.7) present in blood that degrades many blood plasma proteins, most notably, fibrin clots. The degradation of fibrin is termed fibrinolysis. Plasminogen (PLG) is a circulating zymogen that is converted to the active enzyme plasmin by cleavage of the peptide bond between Arg-560 and Val-561, which is mediated by urokinase and tissue plasminogen activator. The main function of plasmin is to dissolve fibrin blood clots. Plasmin, like trypsin, belongs to the family of serine proteases.

Plasmin is a serine protease that is released as plasminogen from the liver into the circulation and activated by tissue plasminogen activator (tPA), urokinase plasminogen activator (uPA), and factor XII (Hageman factor).