Antithrombin-S195A factor Xa-heparin structure reveals the allosteric mechanism of antithrombin activation.

ABSTRACT: Regulation of blood coagulation is critical for maintaining blood flow, while preventing excessive bleeding or thrombosis. One of the principal regulatory mechanisms involves heparin activation of the serpin antithrombin (AT). Inhibition of several coagulation proteases is accelerated by up to 10,000-fold by heparin, either through bridging AT and the protease or by inducing allosteric changes in the properties of AT. The anticoagulant effect of short heparin chains, including the minimal AT-specific pentasaccharide, is mediated exclusively through the allosteric activation of AT towards efficient inhibition of coagulation factors (f) IXa and Xa. Here we present the crystallographic structure of the recognition (Michaelis) complex between heparin-activated AT and S195A fXa, revealing the e

SUBMITTER: Johnson DJ 

PROVIDER: S-EPMC1456925 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature