7PTI:
reference: Structural effects induced by removal of a disulfide-bridge: the X-ray structure of the C30A/C51A mutant of basic pancreatic trypsin inhibitor at 1.6 A., Eigenbrot C, Randal M, Kossiakoff AA, Protein Eng 1990 Jul;3(7):591-8. PMID: 1699222

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