4WBG:
reference: A Conformational Change Observed in the Active Site of Class C beta-Lactamase MOX-1 in Binding Aztreonam., Oguri T, Ishii Y, Shimizu-Ibuka A, Antimicrob Agents Chemother. 2015 Jun 8. pii: AAC.04428-14. PMID: 26055361

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