3MN0:
reference: Introducing a 2-His-1-Glu nonheme iron center into myoglobin confers nitric oxide reductase activity., Lin YW, Yeung N, Gao YG, Miner KD, Lei L, Robinson H, Lu Y, J Am Chem Soc. 2010 Jul 28;132(29):9970-2. PMID: 20586490

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