Molecular model of human FVIIa crystal structure with the Kunitz-1 domain of TFPI. (A) Molecular model of FVIIa crystal structure with the Kunitz-1 domain of TFPI created in Pymol. The hydrogen bond network between residues within the substrate-binding pocket of FVIIa and the Kunitz-1 domain of TFPI adapted from PDB ID: 1FAK.31 R147 and K192 were illustrated as cyan stick. The Kunitz-1 domain of TFPI was shown as yellow stick. The catalytic triads in the active site were shown in magenta. Other residues within the substrate-binding pocket were shown in green. Hydrogen bonds were shown as black dotted lines. (B) The amino acid sequences at the cleavage sites of FX, binding with FVIIa, were compared with the Kunitz-1 domain of TFPI. The amino acids of FX and TFPI bound to R147 and K192 of FVIIa were highlighted in gray.
