3UCP:
reference: The Crystal Structure of the Extracellular 11-heme Cytochrome UndA Reveals a Conserved 10-heme Motif and Defined Binding Site for Soluble Iron Chelates., Edwards MJ, Hall A, Shi L, Fredrickson JK, Zachara JM, Butt JN, Richardson DJ, Clarke TA, Structure. 2012 Jul 3;20(7):1275-84. Epub 2012 Jun 7. PMID: 22682743

This OCA Structure page
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