4I3D:
reference: A bilirubin-inducible fluorescent protein from eel muscle., Kumagai A, Ando R, Miyatake H, Greimel P, Kobayashi T, Hirabayashi Y, Shimogori T, Miyawaki A, Cell. 2013 Jun 20;153(7):1602-11. doi: 10.1016/j.cell.2013.05.038. Epub 2013 Jun , 13. PMID: 23768684

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