4GFH:
reference: Structure of a topoisomerase II-DNA-nucleotide complex reveals a new control mechanism for ATPase activity., Schmidt BH, Osheroff N, Berger JM, Nat Struct Mol Biol. 2012 Nov;19(11):1147-54. doi: 10.1038/nsmb.2388. Epub 2012, Sep 30. PMID: 23022727

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