1BR5:
reference: Structure-based identification of a ricin inhibitor., Yan X, Hollis T, Svinth M, Day P, Monzingo AF, Milne GW, Robertus JD, J Mol Biol 1997 Mar 14;266(5):1043-9. PMID: 9086280

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