PMID: 18063751 , Related PDB id: ID2R9Y

Authors:

Law RH, Sofian T, Kan WT, Horvath AJ, Hitchen CR, Langendorf CG, Buckle AM, Whisstock JC, Coughlin PB

Title:

X-ray crystal structure of the fibrinolysis inhibitor alpha2-antiplasmin.

Journal:

Blood. 2008 Feb 15;111(4):2049-52. Epub 2007 Dec 6.

Abstract:

The serpin alpha(2)-antiplasmin (SERPINF2) is the principal inhibitor of plasmin and inhibits fibrinolysis. Accordingly, alpha(2)-antiplasmin deficiency in humans results in uncontrolled fibrinolysis and a bleeding disorder. alpha(2)-antiplasmin is an unusual serpin, in that it contains extensive N- and C-terminal sequences flanking the serpin domain. The N-terminal sequence is crosslinked to fibrin by factor XIIIa, whereas the C-terminal region mediates the initial interaction with plasmin. To understand how this may happen, we have determined the 2.65A X-ray crystal structure of an N-terminal truncated murine alpha(2)-antiplasmin. The structure reveals that part of the C-terminal sequence is tightly associated with the body of the serpin. This would be anticipated to position the flexible plasmin-binding portion of the C-terminus in close proximity to the serpin Reactive Center Loop where it may act as a template to accelerate serpin/protease interactions.