Biochem Exam 3: Regulation Of OxPhos Flashcards
How do electrons flow in the ETC when looking at redox potential?
Lower redox potential to highest redox potential
T/F
Change in redox potential (E) and change in energy (G) are inversely related
True
What 2 factors constitute a proton-motive force (PMF) to drive ATP synthesis by complex V?
- PH gradient
2. Membrane potential
What 3 postulates does the chemiosmotic theory consist of?
- Mitochondrial electron transport chain translocates protons across the inner mitochondrial membrane
- ATP synthase uses pmf to drive phosphorylation
- Inner mitochondrial membrane is impermeable to H+ & OH- ions.
What type of structure is the ATP synthase (complex V)?
Ball and stick
This subunit is the stick subunit embedded in membrane (has proton channel). What subunit is it?
Fo
This subunit is the ball subunit; it protrudes into the matrix side (contains catalytic domains). What subunit is it?
F1 subunit
What is the F1 subunit made of in ATP synthase?
Alpha 3, beta 3, gamma, delta, epsilon
How are the alpha and beta arranged in the ATP synthase F1 subunit?
Alternating in a hexameric ring
Which part of F1 subunit is catalytically active?
Beta
What is the stalk of the F1 subunit made of?
Gamma and epsilon
Which of the stalk extends down into the alpha, beta hexamer in ATP synthase for subunit F1?
Gamma (long helical coil)
What part of the mitochondria allows for the proton gradient to be near ATP synthase?
Cristae
T/F
Oligomycin helps ATP synthase (complex V)
False!
Oligomycin disrupts proton transport though the channel
How many protons need to travel through the ATP synthase?
4;
3 to spin it and one to pair with ADP
What is the ATP & ADP carrier?
ATP-ADP translocaase family (located in outer and inner membrane)
-Coupled together
What are the two shuttle system for NADH across the mitochondrial membrane?
- Malate-Aspartate shuttle
2. Glycerophosphate shuttle
Where does the malate-Aspartate shuttle happen?
Heart, liver, and kidneys
Where does the malate-Aspartate shuttle release NADH into the ETC?
Complex 1
Where does the glycerophosphate-shuttle happen?
Skeletal muscle and brain
Where does it release it’s compound (FADH2) in the ETC?
CoQ & pyruvate to the TCA(complex II)
What inhibits complex 1: A. Amytal Rotenone Myxothiazol Piercidin A B. Malonate C. Antimycin D. Co, cyanide, H2S E. Oligomycin
A. Amytal, Rotenone, Myxothiazol, Piericidin A
What inhibits complex 2: A. Amytal, Rotenone, Myxothiazol, Piericidin A B. Malonate C. Antimycin D. Co, cyanide, H2S E. Oligomycin
B. Malonate
What inhibits complex 3: A. Amytal, Rotenone, Myxothiazol, Piericidin A B. Malonate C. Antimycin D. Co, cyanide, H2S E. Oligomycin
C. Antimycin
