4RPA:
reference: Structure of inorganic pyrophosphatase from Staphylococcus aureus reveals conformational flexibility of the active site., Gajadeera CS, Zhang X, Wei Y, Tsodikov OV, J Struct Biol. 2015 Jan 7. pii: S1047-8477(14)00277-9. doi:, 10.1016/j.jsb.2014.12.003. PMID: 25576794

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