lecture 29 oxidative phosphorylation.

Question 1

What is NAD+/NADH

Answer 1

• Nicotinamide Dinucleotide.
• It readily accepts 2e- from metabolic substrates which become oxidized (NAD+ it self-get reduced)
• Funnels 2e- into complex I of the MRC
• If Resulting resulted from cytoplasmic oxidation (Glycolysis) specific transport across inner mitochondrial membrane is required to reach complex I (malate phosphate shuttle or glycerol phosphate shuttle)

Question 2

What is FAD/FADH2

Answer 2

• Flavin Adenine Dinucleotide
• FAD is a cofactor for a lot of complexes. It feeds into complex 2 instead of complex 1 like NAD. FAD gives off 2 ATP .
• FAD is cofactor in succinyl-DH complex II, PDC, aKG-DH

Question 3

How much ATP you get from a pair of FADH2 vs a pair NADH

Answer 3

2 from FADH2 and 3 From NADH

Question 4

How may protein complexes are in the mitochondria?

Answer 4

there are 5.

Question 5

Whats the function of Complex I

Answer 5

• NADH Dehydrogenase.
• Electron carriers are: FMN and FE-S centers.
• Passes e- from NADH onto CoQ
• is a proton pump from NADH onto CoQ

Question 6

Complex II

Answer 6

• Succinate dehydrogenase
• Electron carriers are FAD and Fe-S centers.
• Passes e- from succinate (TCA cycle) onto CoQ
• Not a proton pump

Question 7

Complex III

Answer 7

• Cyt c- Coenzyme Q oxyoreductase
• Electron carriers: Cyt b, Fe-S centers and Cyt C1
• Is a proton pump

Question 8

Complex IV

Answer 8

• Cytochrome C oxydase
• Electron carriers: Cyt a, Cyt a3
• Composed of 13 polypeptides (3 encoded and ynthesized within the mitochondrion)
• is a proton pump
• Passes e- from Cyt C to Oxygen (ultimate acceptor)

Question 9

Comple V

Answer 9

is the ATP synthase: uses proton gradient.