3N8S:
reference: Structures of the Michaelis Complex (1.2 A) and the Covalent Acyl Intermediate (2.0 A) of Cefamandole Bound in the Active Sites of the Mycobacterium tuberculosis beta-Lactamase K73A and E166A Mutants ., Tremblay LW, Xu H, Blanchard JS, Biochemistry. 2010 Nov 16;49(45):9685-7. Epub 2010 Oct 25. PMID: 20961112

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