2QDF:
reference: Structure and function of an essential component of the outer membrane protein assembly machine., Kim S, Malinverni JC, Sliz P, Silhavy TJ, Harrison SC, Kahne D, Science. 2007 Aug 17;317(5840):961-4. PMID: 17702946

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