1TGB:
reference: Crystal structure of bovine trypsinogen at 1-8 A resolution. II. Crystallographic refinement, refined crystal structure and comparison with bovine trypsin., Fehlhammer H, Bode W, Huber R, J Mol Biol 1977 Apr 25;111(4):415-38. PMID: 864704

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