2WDV: E. Coli Succinate:quinone Oxidoreductase (Sqr) With An Empty Quinone-Binding Pocket

Citation:
Abstract
Three new structures of Escherichia coli succinate-quinone oxidoreductase (SQR) have been solved. One with the specific quinone-binding site (Q-site) inhibitor carboxin present has been solved at 2.4 A resolution and reveals how carboxin inhibits the Q-site. The other new structures are with the Q-site inhibitor pentachlorophenol and with an empty Q-site. These structures reveal important details unresolved in earlier structures. Comparison of the new SQR structures shows how subtle rearrangements of the quinone-binding site accommodate the different inhibitors. The position of conserved water molecules near the quinone binding pocket leads to a reassessment of possible water-mediated proton uptake networks that complete reduction of ubiquinone. The dicarboxylate-binding site in the soluble domain of SQR is highly similar to that seen in high resolution structures of avian SQR (PDB 2H88) and soluble flavocytochrome c (PDB 1QJD) showing mechanistically significant structural features conserved across prokaryotic and eukaryotic SQRs.
PDB ID: 2WDVDownload
MMDB ID: 76175
PDB Deposition Date: 2009/3/26
Updated in MMDB: 2012/10
Experimental Method:
x-ray diffraction
Resolution: 3.2  Å
Source Organism:
Similar Structures:
Biological Unit for 2WDV: tetrameric; determined by author and by software (PISA)
Molecular Components in 2WDV
Label Count Molecule
Proteins (4 molecules)
1
Succinate Dehydrogenase Flavoprotein Subunit(Gene symbol: sdhA)
Molecule annotation
1
Succinate Dehydrogenase Iron-sulfur Subunit(Gene symbol: sdhB)
Molecule annotation
1
Succinate Dehydrogenase Cytochrome B556 Subunit(Gene symbol: sdhC)
Molecule annotation
1
Succinate Dehydrogenase Hydrophobic Membrane Anchor Protein(Gene symbol: sdhD)
Molecule annotation
Chemicals (7 molecules)
1
1
2
1
3
1
4
1
5
1
6
1
7
1
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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