2H3T:
reference: A Photoswitchable Miniprotein Based on the Sequence of Avian Pancreatic Polypeptide., Jurt S, Aemissegger A, Guntert P, Zerbe O, Hilvert D, Angew Chem Int Ed Engl. 2006 Aug 25;. PMID: 16933352

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