Structural comparison of the catalytic domains of β-FXIIa and FXIIc. Superposition of the β-FXIIa–compound 1 (cyan) reported in this study and the zymogen form of the FXII catalytic domain (FXIIc, residues 16-244; PDB code 4XDE, gray cartoon). The greatest conformational changes between 2 structures are indicated by dashed lines.