4XQC:
reference: Comprehensive Structural Characterization of the Bacterial Homospermidine Synthase-an Essential Enzyme of the Polyamine Metabolism., Krossa S, Faust A, Ober D, Scheidig AJ, Sci Rep. 2016 Jan 18;6:19501. doi: 10.1038/srep19501. PMID: 26776105

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