1S14:
reference: Crystal structures of Escherichia coli topoisomerase IV ParE subunit (24 and 43 kilodaltons): a single residue dictates differences in novobiocin potency against topoisomerase IV and DNA gyrase., Bellon S, Parsons JD, Wei Y, Hayakawa K, Swenson LL, Charifson PS, Lippke JA, Aldape R, Gross CH, Antimicrob Agents Chemother 2004 May;48(5):1856-64. PMID: 15105144

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