Staphylococcal superantigen-like protein 10 (SSL10) inhibits blood coagulation by binding to prothrombin and factor Xa via their γ-carboxyglutamic acid (Gla) domain

Abstract

Background: Staphylococcal superantigen-like proteins (SSLs) share structural similarity with superantigens but no superantigenic activity. Their functions remained unclear. Results: SSL10 binds to prothrombin and factor Xa via the γ-carboxyglutamic acid domain. SSL10 inhibits the penultimate step of plasma clotting. SSL10 slightly inhibits clotting by coagulase. Conclusion: SSL10 inhibits blood coagulation. Significance: This work presents a novel function of SSLs, disturbing blood coagulation. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.