1LKM:
reference: X-ray crystal structures of reduced rubrerythrin and its azide adduct: a structure-based mechanism for a non-heme diiron peroxidase., Jin S, Kurtz DM Jr, Liu ZJ, Rose J, Wang BC, J Am Chem Soc 2002 Aug 21;124(33):9845-55. PMID: 12175244

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