Cytochrome bc1 complex

Cytochrome bc1 (Cbc1) functions as the central pump which transfers protons across the cell membrane. The protons are used to power the rotation of ATP synthase. Cbc1 binds ubiquinol which carries hydrogen atoms. Cbc1 separates the protons and the electrons. The protons are released in the inner side of the membrane for use by ATP synthase and the electrons are transferred to cytochrome c or to the outer side of the membrane. Plants use cytochrome b6f in the same manner binding plastoquinol as a hydrogen carrier. Stigmatellin inhibits the Cbc1 electron transfer by binding to its quinone oxidation site. Antimycin inhibits Cbc1 by binding to its quinone reduction site. More details in Complex III of Electron Transport Chain. Structural highlights Cbc1 is a composed of 11 proteins and cofactors which include heme-carrying proteins like and and iron-sulfur cluster proteins like . The iron containing moieties are , (where vinyl side chain of heme are replaced by thioether) and .

spinqualitylabelsall models Cytochrome bc1 containing Cb (green), Cc1 (yellow), RISP (beige) and Fe2S2 complex with stigmatellin (PDB entry 1zrt) Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

3D structures of cytochrome bc13D structures of cytochrome bc1

Cytochrome bc1 3D structures