Question

What is the reaction catalyzed by complex III in the electron transport system?

Answer 1

The reaction of complex III

1. Complex III is also called cytochrome bc1
2. The cytochrome bc1 complex also called quinol-cytochrome c reductases
3. Complex III is formed of 11 polypeptide subunits, only 1 of which (cytochrome b) is formed by the mitochondrial genome.
4. It is a third complex in the electron transport chain,
5. It plays an essential role in the biochemical generation of ATP
6. The bc1 complexes are intrinsic membrane proteins
7. Complex III is a complex that carries out a multistep process called oxidative phosphorylation
8. It catalyzes the oxidation of ubihydroquinone and the reduction of cytochrome c in ETS and bacterial photosynthetic and respiratory chains.
9. It gets inhibited by antimycin A.
10. AntimycinA arrests the movement of electrons from either complex I or FADH₂-containing flavoproteins to cytochrome c.
11. In this case, elements foregoing complex III become fully reduced, and those after it become oxidized.

${\mathrm{UQH}}_2+2\mathrm{Cyt}\mathrm{C}({\mathrm{Fe}}^{+3})\underset{}{\to \mathrm{UQ}+2\mathrm{Cyt}\mathrm{C}\left({\mathrm{Fe}}^{+2}\right)+2{\mathrm{H}}^{+}}$

This the equation Complex III catalyzed