4APM:
reference: Babesia divergens and Neospora caninum Apical Membrane Antigen 1 (AMA1) structures reveal selectivity and plasticity in apicomplexan parasite host cell invasion., Tonkin ML, Crawford J, Lebrun ML, Boulanger MJ, Protein Sci. 2012 Nov 20. doi: 10.1002/pro.2193. PMID: 23169033

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