Factor XA binding to phosphatidylserine-containing membranes produces an inactive membrane-bound dimer.

ABSTRACT: Factor Xa (FXa) has a prominent role in amplifying both inflammation and the coagulation cascade. In the coagulation cascade, its main role is catalyzing the proteolytic activation of prothrombin to thrombin. Efficient proteolysis is well known to require phosphatidylserine (PS)-containing membranes that are provided by platelets in vivo. However, soluble, short-chain PS also triggers efficient proteolytic activity and formation of an inactive FXa dimer in solution. In this work, we ask whether PS-containing membranes also trigger formation of an inactive FXa dimer. We determined the proteolytic activity of human FXa toward human Pre2 as a substrate both at fixed membrane concentration (increasing FXa concentration) and at fixed FXa concentration (increasing membrane concentration). Neithe

SUBMITTER: Koklic T 

PROVIDER: S-EPMC2764068 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature