1rwj
c7-type three-heme cytochrome domain
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| , resolution 1.70Å | |||||||
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| Ligands: | |||||||
| Gene: | ORF03300 (Geobacter sulfurreducens) | ||||||
| Related: | 1os6, 1hh5
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
OverviewOverview
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.
About this StructureAbout this Structure
1RWJ is a Single protein structure of sequence from Geobacter sulfurreducens. Full crystallographic information is available from OCA.
ReferenceReference
Structure of a novel c7-type three-heme cytochrome domain from a multidomain cytochrome c polymer., Pokkuluri PR, Londer YY, Duke NE, Erickson J, Pessanha M, Salgueiro CA, Schiffer M, Protein Sci. 2004 Jun;13(6):1684-92. Epub 2004 May 7. PMID:15133162
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