1RWJ

c7-type three-heme cytochrome domain

Summary for 1RWJ

• Entry DOI: 10.2210/pdb1rwj/pdb
• Related: 1hh5 1os6
• Descriptor: Cytochrome c family protein, HEME C (3 entities in total)
• Functional Keywords: multiheme cytochrome c, cytochrome c7, geobacter sulfurreducens, geobacter metallireducens, heme coordination in c-type cytochromes, electron transport
• Biological source: Geobacter sulfurreducens
• Total number of polymer chains: 1
• Total formula weight: 10711.78

Authors

Pokkuluri, P.R.,Londer, Y.Y.,Duke, N.E.C.,Erickson, J.,Pessanha, M.,Salgueiro, C.A.,Schiffer, M. (deposition date: 2003-12-16, release date: 2004-08-03, Last modification date: 2024-10-30)

Primary citation

Pokkuluri, P.R.,Londer, Y.Y.,Duke, N.E.C.,Erickson, J.,Pessanha, M.,Salgueiro, C.A.,Schiffer, M.
Structure of a novel c7-type three-heme cytochrome domain from a multidomain cytochrome c polymer.
Protein Sci., 13:1684-1692, 2004

PubMed Abstract: The structure of a novel c(7)-type cytochrome domain that has two bishistidine coordinated hemes and one heme with histidine, methionine coordination (where the sixth ligand is a methionine residue) was determined at 1.7 A resolution. This domain is a representative of domains that form three polymers encoded by the Geobacter sulfurreducens genome. Two of these polymers consist of four and one protein of nine c(7)-type domains with a total of 12 and 27 hemes, respectively. Four individual domains (termed A, B, C, and D) from one such multiheme cytochrome c (ORF03300) were cloned and expressed in Escherichia coli. The domain C produced diffraction quality crystals from 2.4 M sodium malonate (pH 7). The structure was solved by MAD method and refined to an R-factor of 19.5% and R-free of 21.8%. Unlike the two c(7) molecules with known structures, one from G. sulfurreducens (PpcA) and one from Desulfuromonas acetoxidans where all three hemes are bishistidine coordinated, this domain contains a heme which is coordinated by a methionine and a histidine residue. As a result, the corresponding heme could have a higher potential than the other two hemes. The apparent midpoint reduction potential, E(app), of domain C is -105 mV, 50 mV higher than that of PpcA.

PubMed: 15133162
DOI: 10.1110/ps.04626204

Experimental method

X-RAY DIFFRACTION (1.7 Å)