2bs2
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Membrane protein complexes can support both the generation and utilisation | + | Membrane protein complexes can support both the generation and utilisation of a transmembrane electrochemical proton potential ('proton-motive force'), either by transmembrane electron transfer coupled to protolytic reactions on opposite sides of the membrane or by transmembrane proton transfer. Here we provide the first evidence that both of these mechanisms are combined in the case of a specific respiratory membrane protein complex, the dihaem-containing quinol:fumarate reductase (QFR) of Wolinella succinogenes, so as to facilitate transmembrane electron transfer by transmembrane proton transfer. We also demonstrate the non-functionality of this novel transmembrane proton transfer pathway ('E-pathway') in a variant QFR where a key glutamate residue has been replaced. The 'E-pathway', discussed on the basis of the 1.78-Angstrom-resolution crystal structure of QFR, can be concluded to be essential also for the viability of pathogenic varepsilon-proteobacteria such as Helicobacter pylori and is possibly relevant to proton transfer in other dihaem-containing membrane proteins, performing very different physiological functions. |
==About this Structure== | ==About this Structure== | ||
| - | 2BS2 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Wolinella_succinogenes Wolinella succinogenes] with <scene name='pdbligand=NA:'>NA</scene>, <scene name='pdbligand=FAD:'>FAD</scene>, <scene name='pdbligand=FMR:'>FMR</scene>, <scene name='pdbligand=FES:'>FES</scene>, <scene name='pdbligand=F3S:'>F3S</scene>, <scene name='pdbligand=SF4:'>SF4</scene>, <scene name='pdbligand=HEM:'>HEM</scene> and <scene name='pdbligand=LMT:'>LMT</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. This structure | + | 2BS2 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Wolinella_succinogenes Wolinella succinogenes] with <scene name='pdbligand=NA:'>NA</scene>, <scene name='pdbligand=FAD:'>FAD</scene>, <scene name='pdbligand=FMR:'>FMR</scene>, <scene name='pdbligand=FES:'>FES</scene>, <scene name='pdbligand=F3S:'>F3S</scene>, <scene name='pdbligand=SF4:'>SF4</scene>, <scene name='pdbligand=HEM:'>HEM</scene> and <scene name='pdbligand=LMT:'>LMT</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. This structure supersedes the now removed PDB entry 1QLA. Active as [http://en.wikipedia.org/wiki/Succinate_dehydrogenase Succinate dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.3.99.1 1.3.99.1] Known structural/functional Site: <scene name='pdbsite=AC1:Na+Binding+Site+For+Chain+D'>AC1</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2BS2 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Succinate dehydrogenase]] | [[Category: Succinate dehydrogenase]] | ||
[[Category: Wolinella succinogenes]] | [[Category: Wolinella succinogenes]] | ||
| - | [[Category: Lancaster, C | + | [[Category: Lancaster, C R.D.]] |
[[Category: F3S]] | [[Category: F3S]] | ||
[[Category: FAD]] | [[Category: FAD]] | ||
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[[Category: tricarboxylic acid cycle]] | [[Category: tricarboxylic acid cycle]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:41:01 2008'' |
Revision as of 14:41, 21 February 2008
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QUINOL:FUMARATE REDUCTASE FROM WOLINELLA SUCCINOGENES
Overview
Membrane protein complexes can support both the generation and utilisation of a transmembrane electrochemical proton potential ('proton-motive force'), either by transmembrane electron transfer coupled to protolytic reactions on opposite sides of the membrane or by transmembrane proton transfer. Here we provide the first evidence that both of these mechanisms are combined in the case of a specific respiratory membrane protein complex, the dihaem-containing quinol:fumarate reductase (QFR) of Wolinella succinogenes, so as to facilitate transmembrane electron transfer by transmembrane proton transfer. We also demonstrate the non-functionality of this novel transmembrane proton transfer pathway ('E-pathway') in a variant QFR where a key glutamate residue has been replaced. The 'E-pathway', discussed on the basis of the 1.78-Angstrom-resolution crystal structure of QFR, can be concluded to be essential also for the viability of pathogenic varepsilon-proteobacteria such as Helicobacter pylori and is possibly relevant to proton transfer in other dihaem-containing membrane proteins, performing very different physiological functions.
About this Structure
2BS2 is a Protein complex structure of sequences from Wolinella succinogenes with , , , , , , and as ligands. This structure supersedes the now removed PDB entry 1QLA. Active as Succinate dehydrogenase, with EC number 1.3.99.1 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Evidence for transmembrane proton transfer in a dihaem-containing membrane protein complex., Madej MG, Nasiri HR, Hilgendorff NS, Schwalbe H, Lancaster CR, EMBO J. 2006 Oct 18;25(20):4963-70. Epub 2006 Oct 5. PMID:17024183
Page seeded by OCA on Thu Feb 21 16:41:01 2008
Categories: Protein complex | Succinate dehydrogenase | Wolinella succinogenes | Lancaster, C R.D. | F3S | FAD | FES | FMR | HEM | LMT | NA | SF4 | 2fe-2s | 3fe-4s | 4fe-4s | Citric acid cycle | Dihaem cytochrome b | Electron transport | Fad | Flavoprotein | Fumarate reductase | Heme | Ion-sulphur protein | Iron | Iron-sulfur | Metal-binding | Oxidoreductase | Respiratory chain | Transmembrane | Tricarboxylic acid cycle
