1KN1:
reference: Crystal structure of allophycocyanin from red algae Porphyra yezoensis at 2.2-A resolution., Liu JY, Jiang T, Zhang JP, Liang DC, J Biol Chem 1999 Jun 11;274(24):16945-52. PMID: 10358042

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