3BXU:
reference: Structural insights into the modulation of the redox properties of two Geobacter sulfurreducens homologous triheme cytochromes., Morgado L, Bruix M, Orshonsky V, Londer YY, Duke NE, Yang X, Pokkuluri PR, Schiffer M, Salgueiro CA, Biochim Biophys Acta. 2008 May 9;. PMID: 18534185

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