3ZKW:
reference: Interactions of a Periplasmic Binding Protein with a Tetradentate Siderophore Mimic., Raines DJ, Moroz OV, Wilson KS, Duhme-Klair AK, Angew Chem Int Ed Engl. 2013 Mar 19. doi: 10.1002/anie.201300751. PMID: 23512642

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