1kb9: Difference between revisions

Revision as of 22:31, 2 May 2008

YEAST CYTOCHROME BC1 COMPLEX

OverviewOverview

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 StructureAbout this Structure

1KB9 is a Protein complex structure of sequences from Mus musculus and Saccharomyces cerevisiae. Full crystallographic information is available from OCA.

ReferenceReference

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 Fri May 2 22:31:57 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

@@ Line 1: / Line 1: @@
 [[Image:1kb9.gif|left|200px]]
- {{Structure
+<!--
-|PDB= 1kb9 |SIZE=350|CAPTION= <scene name='initialview01'>1kb9</scene>, resolution 2.30&Aring;
+The line below this paragraph, containing "STRUCTURE_1kb9", creates the "Structure Box" on the page.
-|SITE=
+You may change the PDB parameter (which sets the PDB file loaded into the applet)
-|LIGAND= <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>
+or the SCENE parameter (which sets the initial scene displayed when the page is loaded),
-|ACTIVITY= <span class='plainlinks'>[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] </span>
+or leave the SCENE parameter empty for the default display.
-|GENE=
+-->
-|DOMAIN=
+{{STRUCTURE_1kb9|  PDB=1kb9  |  SCENE=  }}
-|RELATEDENTRY=[[1ezv|1EZV]]
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1kb9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1kb9 OCA], [http://www.ebi.ac.uk/pdbsum/1kb9 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1kb9 RCSB]</span>
-}}
 '''YEAST CYTOCHROME BC1 COMPLEX'''
@@ Line 31: / Line 28: @@
 [[Category: Nett, J H.]]
 [[Category: Trumpower, B L.]]
-[[Category: cardiolipin]]
+[[Category: Cardiolipin]]
-[[Category: oxidoreductase]]
+[[Category: Oxidoreductase]]
-[[Category: phosphatidylcholin]]
+[[Category: Phosphatidylcholin]]
-[[Category: phosphatidylethanolamin]]
+[[Category: Phosphatidylethanolamin]]
-[[Category: phosphatidylinositol]]
+[[Category: Phosphatidylinositol]]
-[[Category: stigmatellin]]
+[[Category: Stigmatellin]]
-[[Category: ubiquinone]]
+[[Category: Ubiquinone]]
-[[Category: undecyl-maltopyranoside,]]
+[[Category: Undecyl-maltopyranoside]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May  2 22:31:57 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:46:01 2008''