1SPJ:
reference: 1.70 A X-ray structure of human apo kallikrein 1: Structural changes upon peptide inhibitor/substrate binding., Laxmikanthan G, Blaber SI, Bernett MJ, Scarisbrick IA, Juliano MA, Blaber M, Proteins 2005 Jan 13;. PMID: 15651049

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