2YKS:
reference: Ligand activation of the prokaryotic pentameric ligand-gated ion channel ELIC., Zimmermann I, Dutzler R, PLoS Biol. 2011 Jun;9(6):e1001101. Epub 2011 Jun 21. PMID: 21713033

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