View source for 1kb9


==YEAST CYTOCHROME BC1 COMPLEX==
<StructureSection load='1kb9' size='340' side='right'caption='[[1kb9]], [[Resolution|resolution]] 2.30&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1kb9]] is a 11 chain structure with sequence from [https://en.wikipedia.org/wiki/Atcc_18824 Atcc 18824] and [https://en.wikipedia.org/wiki/Lk3_transgenic_mice Lk3 transgenic mice]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KB9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1KB9 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CDL:CARDIOLIPIN'>CDL</scene>, <scene name='pdbligand=FES:FE2/S2+(INORGANIC)+CLUSTER'>FES</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=PCF:1,2-DIACYL-SN-GLYCERO-3-PHOSHOCHOLINE'>PCF</scene>, <scene name='pdbligand=PEF:DI-PALMITOYL-3-SN-PHOSPHATIDYLETHANOLAMINE'>PEF</scene>, <scene name='pdbligand=PIE:1,2-DIACYL-SN-GLYCERO-3-PHOSPHOINOSITOL'>PIE</scene>, <scene name='pdbligand=SMA:STIGMATELLIN+A'>SMA</scene>, <scene name='pdbligand=UMQ:UNDECYL-MALTOSIDE'>UMQ</scene>, <scene name='pdbligand=UQ6:5-(3,7,11,15,19,23-HEXAMETHYL-TETRACOSA-2,6,10,14,18,22-HEXAENYL)-2,3-DIMETHOXY-6-METHYL-BENZENE-1,4-DIOL'>UQ6</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1ezv|1ezv]]</div></td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Ubiquinol--cytochrome-c_reductase Ubiquinol--cytochrome-c reductase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.10.2.2 1.10.2.2] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1kb9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1kb9 OCA], [https://pdbe.org/1kb9 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1kb9 RCSB], [https://www.ebi.ac.uk/pdbsum/1kb9 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1kb9 ProSAT]</span></td></tr>
</table>
== Function ==
[[https://www.uniprot.org/uniprot/QCR6_YEAST QCR6_YEAST]] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. QCR6 may mediate formation of the complex between cytochromes c and c1. [[https://www.uniprot.org/uniprot/CYB_YEAST CYB_YEAST]] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. [[https://www.uniprot.org/uniprot/QCR9_YEAST QCR9_YEAST]] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. QCR9 is required for formation of a fully functional complex. [[https://www.uniprot.org/uniprot/QCR2_YEAST QCR2_YEAST]] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. QCR2 is required for the assembly of the complex. [[https://www.uniprot.org/uniprot/QCR1_YEAST QCR1_YEAST]] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. COR1 may mediate formation of the complex between cytochromes c and c1. [[https://www.uniprot.org/uniprot/CY1_YEAST CY1_YEAST]] Heme-containing component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. [[https://www.uniprot.org/uniprot/UCRI_YEAST UCRI_YEAST]] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is a respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. 
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/kb/1kb9_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1kb9 ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
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.

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<ref>PMID:11726495</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1kb9" style="background-color:#fffaf0;"></div>

==See Also==
*[[Cytochrome C 3D structures|Cytochrome C 3D structures]]
*[[Cytochrome bc1 complex|Cytochrome bc1 complex]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Atcc 18824]]
[[Category: Large Structures]]
[[Category: Lk3 transgenic mice]]
[[Category: Ubiquinol--cytochrome-c reductase]]
[[Category: Hunte, C]]
[[Category: Lange, C]]
[[Category: Nett, J H]]
[[Category: Trumpower, B L]]
[[Category: Cardiolipin]]
[[Category: Oxidoreductase]]
[[Category: Oxidoreductase-electron transport complex]]
[[Category: Phosphatidylcholin]]
[[Category: Phosphatidylethanolamin]]
[[Category: Phosphatidylinositol]]
[[Category: Stigmatellin]]
[[Category: Ubiquinone]]
[[Category: Undecyl-maltopyranoside]]