3ZOW:
reference: Structural Characterization of Nitrosomonas europaea Cytochrome c-552 Variants with Marked Differences in Electronic Structure., Can M, Krucinska J, Zoppellaro G, Andersen NH, Wedekind JE, Hersleth HP, Andersson KK, Bren KL, Chembiochem. 2013 Jul 31. doi: 10.1002/cbic.201300118. PMID: 23908017

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