4Q8R:
reference: Crystal structure of the phosphate-binding protein (PBP-1) of an ABC-type phosphate transporter from Clostridium perfringens., Gonzalez D, Richez M, Bergonzi C, Chabriere E, Elias M, Sci Rep. 2014 Oct 16;4:6636. doi: 10.1038/srep06636. PMID: 25338617

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