1. bc1 complex
Stuart Rose
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2. Goal of this presentation:
Function of bc1 complex
Overall Structure
Structural Details Related to Function
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3. bc1 complex function Cytochrome bc1 complex or
ubiquinol:cytochrome c oxidoreductase
“Proton pump”: proton translocation coupled to electron transfer
FOR MORE INFO...
Prof. Crofts’ bc1 Complex Site
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4. Full Dimer
Two monomers with two fold symmetry. Shown here generally colored by chain designation and axis of symmetry located along a vertical line the image plane.
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5. Functional Highlights: Qo Site
Qo site: oxidation of quinol, QH2,to quinone, Q
Conformation of site: Liganding of Q within pocket and Liganding of different inhibitor types within pocket
Movement of Reiske Iron Sulfer Protein (ISP) between two domains: oxidation of quinol to reduction of cytochrome c1 at heme propianate of the cytochrome
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6. Schematic view of Q-cycle:
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7. bc1 complex subunits of interest
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8. Reiske (ISP) Binding Domains
Cyt b
ISP
Cyt c1
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9. Electron Transfer From ISP to cyt c1 and cyt b
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10. Qo Site with Stigmatellin
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11. Quinone, Q, vs Stigmatellin
Oxidized by ISP
Reduces bl
Quinol, QH2, orthographic view
ISP interaction
Interference
with proximate zone
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Stigmatellin, perspective view

12. Distances between redox centers proximal to Qo-site
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13. an electrons view….
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14. Ligation of hemes in Cyt b
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