Marie-Claire Dagher, Atanur Ersayin, Landry Seyve, Mathieu Castellan, Cyril Moreau, Luc Choisnard, Nicole Thielens, Raphaël Marlu, Benoît Polack, Aline Thomas, Institut de biologie structurale (IBS - UMR 5075), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), Translational Innovation in Medicine and Complexity / Recherche Translationnelle et Innovation en Médecine et Complexité - UMR 5525 (TIMC ), VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Département de pharmacochimie moléculaire (DPM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), ISBG, ANR-13-RPIB-0011,MINITEN,Le GD-Xa comme nouveau traitement anti-hémorragique(2013), and European Project: IRS-ARCANE
Gla-domainless factor Xa (GD-FXa) was proposed as a trap to the endogenous anticoagulant Tissue Factor Pathway Inhibitor (TFPI) to restore thrombin generation in hemophilia. Using computational chemistry and experimental approaches, we previously showed that S195A GD-FXa also binds TFPI and restores ex vivo coagulation in hemophilia plasmas.To design a GD-FXa variant with improved anti-TFPI activity and identify suitable sites for mutagenesis, we performed molecular dynamics simulations. The calculations identified residues R150FXa and K96FXa as cold-spots of interaction between GD-FXa and the K2 domain of TFPI. In the three-dimensional model, both residues are facing TFPI hydrophobic residues and are thus potential candidates for mutagenesis into hydrophobic residues to favor an improved protein-protein interaction.Catalytically inactive GD-FXa variants containing the S195A mutation and additional mutations as K96Y, R150I, R150G and R150F were produced to experimentally confirm these computational hypotheses. Among these mutants, the R150FFXA showed increased affinity for TFPI as theoretically predicted, and was also more effective than S195A GD-FXa in restoring coagulation in FVIII deficient plasmas. Moreover, the R150 mutants lost interaction with antithrombin, which is favorable to extend their half-life.