Function-stabilizing mechanism of plasminogen activator inhibitor type 1 induced upon binding to alpha(sub 1)-acid glycoprotein

The mechanism by which alpha1-acid glycoprotein (AGP), as well as its recombinant fragment AGP(sub 118-201, interacts exclusively with the active form of plasminogen activator inhibitor 1 (PAI-1) and stabilizes its conformation is described. Results suggest that AGP binding stabilizes the active conformation of PAI-1 by restricting the movement of beta-sheet A and thereby preventing insertion of the reactive center loop.