1RB7:
reference: Microseed matrix screening to improve crystals of yeast cytosine deaminase., Ireton GC, Stoddard BL, Acta Crystallogr D Biol Crystallogr 2004 Mar;60(Pt 3):601-5. Epub 2004 Feb, 25. PMID: 14993707

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