4PA8:
reference: A Promiscuous De Novo Retro-Aldolase Catalyzes Asymmetric Michael Additions via Schiff Base Intermediates., Garrabou X, Beck T, Hilvert D, Angew Chem Int Ed Engl. 2015 Mar 16. doi: 10.1002/anie.201500217. PMID: 25777153

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