2GP9:
reference: Crystal structure of thrombin in a self-inhibited conformation., Pineda AO, Chen ZW, Bah A, Garvey LC, Mathews FS, Di Cera E, J Biol Chem. 2006 Oct 27;281(43):32922-8. Epub 2006 Sep 5. PMID: 16954215

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