2MBO:
reference: Unique structural, dynamical, and functional properties of k11-linked polyubiquitin chains., Castaneda CA, Kashyap TR, Nakasone MA, Krueger S, Fushman D, Structure. 2013 Jul 2;21(7):1168-81. doi: 10.1016/j.str.2013.04.029. PMID: 23823328

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