Three different heparin-catalyzed inhibitor/protease reactions were studied: antithrombin III/thrombin, heparin cofactor II/thrombin, antithrombin III/factor Xa. The three reactions were saturable with respect to both inhibitor and protease. The initial reaction velocity, for each reaction, could be described by the general rate equation for a random-order bireactant enzyme-catalyzed reaction. ...

A kinetic model is presented for the comparison of potential proteolytic processing activities of wild-type and mutant human immunodeficiency virus proteases in the presence and absence of protease inhibitors. The protease processing of gag substrate in the immature virions is assessed by the kinetic parameters, kcat, Km and Ki. The relationship of the estimated potential processing activities ...

Pepstatin has been shown to be an extremely potent inhibitor of human renin (Ki = 1.3 X lo-lo M). Kinetic analyses by several techniques show reversible interaction of pepstatin with renin and classical noncofipetitive inhibition. The high affinity of pepstatin for renin allows kinetic determination of the molarity of the enzyme in partially purified preparations. This method has been validated...