4LE6:
reference: Structural and Enzymatic Characterization of the Phosphotriesterase OPHC2 from Pseudomonas pseudoalcaligenes., Gotthard G, Hiblot J, Gonzalez D, Elias M, Chabriere E, PLoS One. 2013 Nov 4;8(11):e77995. doi: 10.1371/journal.pone.0077995. PMID: 24223749

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