20: ELECTRON TRANSPORT CHAIN

DEFINE: Oxidative phosphorylation

A process that captures the energy of high-energy e- to synthesize ATP

Where exactly does ETC and ATP synthesis occur in the cell?

Mitochondria

The outer mitochondrial membrane is…?

Permeable to most smaller ions & mols (porin channel protein)

The inner mbrane, folded into cristae is…?

Impermeable to most mols

Where does Pyruvate oxidation (form acetyl CoA), CAC & fatty acid oxidation occur?

Matrix of mitochondria

DEFINE: Reduction potential Eo’ (redox potential)

Measure of a mol’s tendency to donate or accept electrons

Stronk reducing agent readily…

DONATES electrons and has a (-) Eo’ (becomes oxidized during the redox rxn)

Stronk oxidizing agent readily…

ACCEPTS electrons and has (+) Eo’ (becomes reduced during the redox rxn)

Where does Coenzyme Q derive from?

Isoprene

DEFINE: Coenzyme Q

Binds proton (QH2) as well as electrons and can exist in several oxidation, such Q are represent in inner mitochondrial mbrane in what is called the Q pool

Where differentiates Succinate Q-reductase to the other ETC Proteins?

It’s not a proton pump, instead delivers e- from FADH2 to Complex III

Complex I is…

NADH-Q oxidoreductase 

Complex III is…

Q-cytochrome c oxidoreductase

Complex IV is…

Cytochrome c oxidase

Complex II is…

Succinate Q-reductase

Which enzyme from the CAC is also part of Complex II?

Succinate dehydrogenase

Who catalyzes the e- from QH2 that are used to reduce 2 mols of cytochrome c?

Q-cytochrome c oxidoreductase 

What’s the mechanism called for coupling e- transfer from QH2 to cytochrome c

The Q cycle

In a single Q cycle, how many protons are pumped out of the mitochondria & how many more are REMOVED from the matrix

4 & 2

Cytochrome c oxidase accepts how many e- from how many mols of cytochrome c?

4 & 4

In cytochrome c oxidase rxn, 8 protons are REMOVED from the matrix. How many of those protons are used to reduce O2 & how many are pumped into the intermbrane space?

4 & 4