3AJC:
reference: Structural insight into the rotational switching mechanism of the bacterial flagellar motor., Minamino T, Imada K, Kinoshita M, Nakamura S, Morimoto YV, Namba K, PLoS Biol. 2011 May;9(5):e1000616. doi: 10.1371/journal.pbio.1000616. Epub 2011, May 10. PMID: 21572987

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