1M6K:
reference: Comparison of beta-lactamases of classes A and D: 1.5-A crystallographic structure of the class D OXA-1 oxacillinase., Sun T, Nukaga M, Mayama K, Braswell EH, Knox JR, Protein Sci 2003 Jan;12(1):82-91. PMID: 12493831

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