1kb9
From Proteopedia
(New page: 200px<br /> <applet load="1kb9" size="450" color="white" frame="true" align="right" spinBox="true" caption="1kb9, resolution 2.30Å" /> '''YEAST CYTOCHROME BC...) |
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| - | [[Image:1kb9.gif|left|200px]]<br /> | + | [[Image:1kb9.gif|left|200px]]<br /><applet load="1kb9" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1kb9" size=" | + | |
caption="1kb9, resolution 2.30Å" /> | caption="1kb9, resolution 2.30Å" /> | ||
'''YEAST CYTOCHROME BC1 COMPLEX'''<br /> | '''YEAST CYTOCHROME BC1 COMPLEX'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Biochemical data have shown that specific, tightly bound phospholipids are | + | Biochemical data have shown that specific, tightly bound phospholipids are essential for activity of the cytochrome bc1 complex (QCR), an integral membrane protein of the respiratory chain. However, the structure and function of such phospholipids are not yet known. Here we describe five phospholipid molecules and one detergent molecule in the X-ray structure of yeast QCR at 2.3 A resolution. Their individual binding sites suggest specific roles in facilitating structural and functional integrity of the enzyme. Interestingly, a phosphatidylinositol molecule is bound in an unusual interhelical position near the flexible linker region of the Rieske iron-sulfur protein. Two possible proton uptake pathways at the ubiquinone reduction site have been identified: the E/R and the CL/K pathway. Remarkably, cardiolipin is positioned at the entrance to the latter. We propose that cardiolipin ensures structural integrity of the proton-conducting protein environment and takes part directly in proton uptake. Site-directed mutagenesis of ligating residues confirmed the importance of the phosphatidylinositol- and cardiolipin-binding sites. |
==About this Structure== | ==About this Structure== | ||
| - | 1KB9 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] and [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with HEM, FES, SMA, UQ6, PIE, PEF, CDL, PCF and UMQ as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Ubiquinol--cytochrome-c_reductase Ubiquinol--cytochrome-c reductase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.10.2.2 1.10.2.2] Full crystallographic information is available from [http:// | + | 1KB9 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] and [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with <scene name='pdbligand=HEM:'>HEM</scene>, <scene name='pdbligand=FES:'>FES</scene>, <scene name='pdbligand=SMA:'>SMA</scene>, <scene name='pdbligand=UQ6:'>UQ6</scene>, <scene name='pdbligand=PIE:'>PIE</scene>, <scene name='pdbligand=PEF:'>PEF</scene>, <scene name='pdbligand=CDL:'>CDL</scene>, <scene name='pdbligand=PCF:'>PCF</scene> and <scene name='pdbligand=UMQ:'>UMQ</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Ubiquinol--cytochrome-c_reductase Ubiquinol--cytochrome-c reductase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.10.2.2 1.10.2.2] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KB9 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Hunte, C.]] | [[Category: Hunte, C.]] | ||
[[Category: Lange, C.]] | [[Category: Lange, C.]] | ||
| - | [[Category: Nett, J | + | [[Category: Nett, J H.]] |
| - | [[Category: Trumpower, B | + | [[Category: Trumpower, B L.]] |
[[Category: CDL]] | [[Category: CDL]] | ||
[[Category: FES]] | [[Category: FES]] | ||
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[[Category: undecyl-maltopyranoside]] | [[Category: undecyl-maltopyranoside]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:32:09 2008'' |
Revision as of 11:32, 21 February 2008
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YEAST CYTOCHROME BC1 COMPLEX
Overview
Biochemical data have shown that specific, tightly bound phospholipids are essential for activity of the cytochrome bc1 complex (QCR), an integral membrane protein of the respiratory chain. However, the structure and function of such phospholipids are not yet known. Here we describe five phospholipid molecules and one detergent molecule in the X-ray structure of yeast QCR at 2.3 A resolution. Their individual binding sites suggest specific roles in facilitating structural and functional integrity of the enzyme. Interestingly, a phosphatidylinositol molecule is bound in an unusual interhelical position near the flexible linker region of the Rieske iron-sulfur protein. Two possible proton uptake pathways at the ubiquinone reduction site have been identified: the E/R and the CL/K pathway. Remarkably, cardiolipin is positioned at the entrance to the latter. We propose that cardiolipin ensures structural integrity of the proton-conducting protein environment and takes part directly in proton uptake. Site-directed mutagenesis of ligating residues confirmed the importance of the phosphatidylinositol- and cardiolipin-binding sites.
About this Structure
1KB9 is a Protein complex structure of sequences from Mus musculus and Saccharomyces cerevisiae with , , , , , , , and as ligands. Active as Ubiquinol--cytochrome-c reductase, with EC number 1.10.2.2 Full crystallographic information is available from OCA.
Reference
Specific roles of protein-phospholipid interactions in the yeast cytochrome bc1 complex structure., Lange C, Nett JH, Trumpower BL, Hunte C, EMBO J. 2001 Dec 3;20(23):6591-600. PMID:11726495
Page seeded by OCA on Thu Feb 21 13:32:09 2008
Categories: Mus musculus | Protein complex | Saccharomyces cerevisiae | Ubiquinol--cytochrome-c reductase | Hunte, C. | Lange, C. | Nett, J H. | Trumpower, B L. | CDL | FES | HEM | PCF | PEF | PIE | SMA | UMQ | UQ6 | Cardiolipin | Oxidoreductase | Phosphatidylcholin | Phosphatidylethanolamin | Phosphatidylinositol | Stigmatellin | Ubiquinone | Undecyl-maltopyranoside
