The coagulating enzymes, such as thrombin or thrombase (the fibrin ferment) and rennin, which causes the clotting of milk.
"Dietetics for Nurses" by Fairfax T. Proudfit
It is not yet certain what is the nature of the final reaction between fibrinogen and thrombin.
"Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 1" by Various
Thrombin Generation Assay Aids Development.
Hemostatis Use Thrombin to Curb Bleeding.
The products use thrombin, a natural component of the clotting cascade.
Warning Issued For Injecting Topical Thrombin Intravascularly.
The Institute for Safe Medication Practices (ISMP) recently warned about the dangers of accidentally giving topical thrombin intravascularly, since some packages come with a syringe.
Thrombin Activity Propagates in Space During Blood Coagulation as an Excitation Wave.