4BEM:
reference: High-resolution structure and mechanism of an F/V-hybrid rotor ring in a Na(+)-coupled ATP synthase., Matthies D, Zhou W, Klyszejko AL, Anselmi C, Yildiz O, Brandt K, Muller V, Faraldo-Gomez JD, Meier T, Nat Commun. 2014 Nov 10;5:5286. doi: 10.1038/ncomms6286. PMID: 25381992

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