1PBP:
reference: Fine tuning the specificity of the periplasmic phosphate transport receptor. Site-directed mutagenesis, ligand binding, and crystallographic studies., Wang Z, Choudhary A, Ledvina PS, Quiocho FA, J Biol Chem 1994 Oct 7;269(40):25091-4. PMID: 7929197

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