Chemiosmosis and ATP synthesis

• Four enzymes in the mitochondrial inner membrane:
• - NADH dehydrogenase
• - Bc1 complex 
• - Cytochome oxidase complex
• - Succinate dehydrogenase 

• Two electron carriers:
• - Ubiquinone
• -Cytochrome C

• -NADH n FADH₂ need to b converted to ATP 
• - happens in the inner membrane of mitochondria
• - NADH and FADH₂ bcome oxydized, allowing transporters to pump H⁺ across membrane.
• - Generate electrical current _{(charge different across the membrane from H⁺ being pump out of mitochondria)} 
• - H⁺ flow through ATP synthase.

• NADH n FADH2 both donate 2e- 
• - NADH to Bc 1 complex
• - FADH² to NADH dehydrogenase 

These high-energy e^- re transfer from complexes w low e^- affinity. (NADH dehydrogenase) to those w higher affinity (cytochrome oxidase complex)

Reduction of complexes allows H+ to b pumped out of matrix to inner membrane space, creating a charge gradient and H+ gradient.

Succinate dehydrogenase (las step of energy harvest II in krebs) reduces ubiquinone using FADH₂ as an e^- carrier

- F₀ is a rotor that is powered by H⁺. Rotation turns F_i through a stator.

• - F_i has 3alpha n 3betas sub units.
•   > sub units bind ADP and Pi force them together to make ATP _{(lose, tight, open comformation).} 

• - F_i creates ATP as it turns
•   > 3.33 ATP per revolution or 10H⁺ 

• - Oxygen is the terminal e- acceptor 
•   > produces water

• - Glycolysis: 
•   > 2 ATP  
•   > 2 NADH x 2.5 = 1 ATP/molecule

• - Krebs:
•   > 6 NADH x 2.5 ATP
•   > 2 FADH x 1.5 ATP(o.75+0.75 = 1.5) 
•   > 2 GTP x 1 ATP   
• * 30 ATP eukariote 
• * 32 ATP prokariote