5HWZ:
reference: Elucidation of the heme active site electronic structure affecting the unprecedented nitrite dismutase activity of the ferriheme b proteins, the nitrophorins., He C, Ogata H, Lubitz W, Chem Sci. 2016 Aug 1;7(8):5332-5340. doi: 10.1039/c6sc01019a. Epub 2016 Apr 25. PMID: 30155185

This OCA Structure page
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