The domain of thrombomodulin that binds to the anion-binding exosite of thrombin was identified by comparing the binding of fragments of thrombomodulin to thrombin with that of Hirugen, a 12-residue peptide of hirudin that is known to bind to the anion-binding exosite of thrombin. Three soluble fragments of thrombomodulin, containing (i) the six repeated growth factor-like domains of thrombomod...

The presence of procoagulants and fibrin deposition have been dem onstrated in malignant tumors. Although thrombin, a key enzyme in coagulation, has other various biological functions, the significance of its presence in tumors is not known. We studied the effects of thrombin on the expression of urokinase-type plasminogen activator (uPA) which is known to play a role in tumor invasion, using a...

Aggregation of platelets is an essential step in the formation of a stable blood clot during vascular injury. The trypsin-like protease thrombin acts as the dominant agonist of platelet activation on engagement of protease-activated receptors (PARs). Important details on the molecular aspects of thrombin-PAR interactions have been revealed recently by structural biology. In the case of human pl...

Previous studies from several aboratories have shown that thrombin is inactivated by tetranitromethane with the formation of nitrotyrosine. The inactivation is characterized by an apparently greater loss of fibrinogen-clotting activity than activity toward synthetic ester substrates, suggesting that the residues modified by tetranitromethane are involved in the interaction of thrombin with ...

Background and Aims: The angiotensin-(1-7)/angiotensin-converting enzyme 2/Mas receptor axis counter-regulates the detrimental effects of angiotensin II. Beneficial effects of angiotensin-(1-7), including anti-inflammation, oxidative stress reduction, and anti-thrombosis, have been reported. Previous studies documented that ramipril decreased thrombin generation in human hypertension and that t...

Stable enzyme precipitate coatings (EPCs) with high enzyme loading were employed to develop a sensitive and reliable detection protocol, termed EPC-linked aptamer assay (EPC-LAA). EPC-LAA achieved the limit of detection to be 0.5 ng per mL of thrombin (13.5 pM), and maintained a reasonably stable detection signal even after storing all the reagents at 40 °C for 66 days.

Intact human platelets loaded with 32PO4 contain multiple phosphorylated proteins. Thrombin treatment of intact 32PO4-loaded platelets results in a 2-6-fold increase in phosphorylation of a platelet protein (designated "peak 7" protein) of approximately 40,000 mol wt as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis and by gel filtration on Sephadex G-150. A similar inc...

The prothrombin activation intermediates meizothrombin and meizothrombin(desF1) (meizothrombin that has been autoproteolyzed to remove fragment 1) have been obtained in a relatively pure, active form with minimal autolysis, making them suitable for enzymatic characterization. When compared at equimolar concentrations, cY-thrombin, fragment 1.2+(rthrombin, meizothrombin(desFl), and meizothrombin...

The kinetic mechanism of Na(+) binding to thrombin was resolved by stopped-flow measurements of intrinsic fluorescence. Na(+) binds to thrombin in a two-step mechanism with a rapid phase occurring within the dead time of the spectrometer (<0.5 ms) followed by a single-exponential slow phase whose k(obs) decreases hyperbolically with increasing [Na(+)]. The rapid phase is due to Na(+) binding to...