1EZS:
reference: Compromise and accommodation in ecotin, a dimeric macromolecular inhibitor of serine proteases., Gillmor SA, Takeuchi T, Yang SQ, Craik CS, Fletterick RJ, J Mol Biol 2000 Jun 16;299(4):993-1003. PMID: 10843853

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).