Plasmin Activity and Milk Coagulation

Coagulation factor XIIIa is inactivated by plasmin.

Coagulation factor XIIIa (FXIIIa) is a transglutaminase that covalently cross-links fibrin and other proteins to fibrin to stabilize blood clots and reduce blood loss. A clear mechanism to describe the physiological inactivation of FXIIIa has been elusive. Here, we show that plasmin can cleave FXIIIa in purified systems and in blood. Whereas zymogen FXIII was not readily cleaved by plasmin, FXI...

Alphas1-casein, milk composition and coagulation properties of goat milk

Amounts of alphas1-casein (as1-CN), protein, fat, SNF and total solids were measured in 125 goat milk samples. Coagulation time, coagulation rate and curd ®rmness were measured in 75 goat milk samples by dynamic mechanical analysis using a Bohlin VOR Rheometer. After adjustments were made for month, time of milk collection and animal age, it was con®rmed that goat milk with high percent total s...

Proteolytic processing of human coagulation factor IX by plasmin.

Previous studies have shown that thrombin generation in vivo caused a 92% decrease in factor IX (F.IX) activity and the appearance of a cleavage product after immunoblotting that comigrated with activated F.IX (F.IXa). Under these conditions, the fibrinolytic system was clearly activated, suggesting plasmin may have altered F.IX. Thus, the effect(s) of plasmin on human F.IX was determined in vi...

The effects of high power ultrasonic energy on milk plasmin activity

The shelf life of pasteurized milk is limited by heat-stable proteases that undergo depolymerization, causing age gelation and bitterness. Proteolysis of milk during storage can be attributed to both native proteases and the proteases produced by bacteria, such as plasmin, which is the major native protease in milk. Ultra-high temperature (UHT) processing (>135°C for 2 s) inactivates proteases ...

Determination of plasmin (alkaline milk proteinase) and chymosin in milk products by the ELISA assay