5KMS:
reference: The mechanism of catalysis by type-II NADH:quinone oxidoreductases., Blaza JN, Bridges HR, Aragao D, Dunn EA, Heikal A, Cook GM, Nakatani Y, Hirst J, Sci Rep. 2017 Jan 9;7:40165. doi: 10.1038/srep40165. PMID: 28067272

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