4R6X:
reference: An Alternate Mechanism for the Methylation of Phosphoethanolamine Catalyzed by Plasmodium falciparum Phosphoethanolamine Methyltransferase., Saen-Oon S, Lee SG, Jez JM, Guallar V, J Biol Chem. 2014 Oct 6. pii: jbc.M114.611319. PMID: 25288796

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