DD - Oxidative Phosphorylation Flashcards
How does NADH enter the mitochondrial matrix?
Porins
What is the Malate-Aspartate Shuttle?
- Results in the electrons and protons from the cytoplasmic NADH to be transferred to the NAD+ in the mitochondrial matrix
- 3 ATP per NADH produced
- Another method is the Glycerol-Phosphate Shuttle (Produces 2 ATP per NADH)
Where does Oxidative Phosphorylation occur?
In the mitochondrial membrane
What is oxidative phosphorylation?
The oxidation of the NADH/FADH2 to regenerate NAD+/FAD that produces ATP by the phosphorylation of ADP
Where is FADH2 made and which enzyme makes it?
In the inner membrane
Succinate Dehydrogenase
Are oxidation reactions endergonic or exergonic?
Exergonic
What is the final electron acceptor?
Molecular Oxygen
What 3 complexes are involved in the oxidation of NADH?
Complex I,III and IV
What occurs in complex 1 (NADH-Q reductase)?
- Oxidises NADH and transfers 2 electrons to ubiquinone
- Also transfers 4 H+ across the inner membrane
- Reduced ubiquinone = ubiquinol (QH2)
- QH2 delivers electrons to complex III
What occurs in complex 3 (Q-cytochrome-c oxidoreductase)?
- 2 electrons transferred from QH2 to cytochrome-c
- 1 electron transferred to cytochrome-c and the other is stored internally and then tranferred
- 4H+ transferred
What occurs in complex 4 (Cytochrome oxidase)?
- Transfers 2 electrons from cytochrome-c to the mitochondrial matrix
- Also 2H+ transferred
- Oxygen reduced to H2O on the matrix side
What 3 complexes are involved in the Oxidation of FADH2?
Complex II,III and IV
How many protons are transferred in the oxidation of NADH?
10H+
What 3 complexes are involved in the oxidation of NADH?
Complex I,III and IV
How many protons are transferred in the oxidation of FADH2?
6H+
