Confused and have questions? We’ve got answers. With Chegg Study, you can get step-by-step solutions to your questions from an expert in the field. If you rather get 1:1 study help, try 30 minutes of free online tutoring with Chegg Tutors.


From Biology-Online Dictionary | Biology-Online Dictionary
(Redirected from Thrombosin)
Jump to: navigation, search



An activated form of factor II that is generated in blood clotting and acts as a catalyst during the conversion of fibrinogen into fibrin


Thrombin is a protease (34 kD) generated in blood clotting that acts on fibrinogen to produce fibrin. It consists of two chains: A and B chains that are linked by a disulphide bond. B chain has sequence homology with pancreatic serine proteases.

Thrombin is produced from prothrombin by the action either of the extrinsic system (tissue factor _ phospholipid) or, more importantly, the intrinsic system (contact of blood with a foreign surface or connective tissue). Both extrinsic and intrinsic systems activate plasma factor X to form factor Xa, which, then, in conjunction with phospholipid (tissue derived or platelet factor 3) and factor V, catalyses the conversion. In humans, it is encoded by the F2 gene.

Thrombin acts on soluble fibrinogen to be converted into insoluble fibrin strands. Thrombin time refers to the time required for the conversion of fibrinogen into fibrin.


  • fibrinogenase
  • thrombase
  • thrombofort
  • thrombin-C
  • tropostasin
  • thrombosin
  • activated blood-coagulation factor II
  • (blood) coagulation factor IIa
  • (blood) clotting factor IIa
  • factor IIa
  • E thrombin
  • beta-thrombin
  • gamma-thrombin

See also:

Related term(s):