4BNP:
reference: Evolution of a Transition State: Role of Lys100 in the Active Site of Isocitrate Dehydrogenase., Miller SP, Goncalves S, Matias PM, Dean AM, Chembiochem. 2014 May 2. doi: 10.1002/cbic.201400040. PMID: 24797066

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