1QBF:
reference: Solution structure of monomeric peptide YY supports the functional significance of the PP-fold., Keire DA, Kobayashi M, Solomon TE, Reeve JR Jr, Biochemistry 2000 Aug 15;39(32):9935-42. PMID: 10933813

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