1OQU:
reference: A protein carboxylate coordinated oxo-centered tri-nuclear iron complex with possible implications for ferritin mineralization., Hogbom M, Nordlund P, FEBS Lett 2004 Jun 4;567(2-3):179-82. PMID: 15178319

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