Chapter 11: 11.1 ATP Synthesis Flashcards
List:
Electron Carriers (Donors)
- NADH
- FADH2
Describe:
NADH
Donates 2 electrons to complex I of the electron transport chain (ETC)
Describe:
FADH2
Donates 2 electrons to complex II of the ETC
List:
Electron Carriers (Prosthetic Groups)
- FMN
- Iron-Sulfur Clusters
- Coenzyme Q (ubiquinone)
- Cytochromes
- Copper Ions
- Oxygen
Describe:
FMN
Found in complex I of the ETC
* Accepts 2 electrons
Describes:
Iron-Sulfur Clusters
Found in Complexes I, II, and III
* Accepts 1 electron
Describes:
Coenzyme Q (ubiquinone)
Shuttles electrons from complexes I & II to Complex III
* Accepts 2 electrons
Describe:
Cytochromes
Heme-containing proteins (possess protoporphyrin IX moiety)
* Can accept 1 electron
What are the different cytochromes?
- Cytochrome a - Complex IV
- Cytochrome b - Complex III
- Cytochrome c - Complex III
Describe:
Copper Ions
Protein bound in complex IV
* Can accept 2 electrons
Describe:
Oxygen
The final electron acceptor (from complex IV)
* One O2 accepts 4 electrons from 4 cytochrome c proteins
Which prosthetic groups carry 1 electron?
- Iron-Sulfur Clusters
- Cytochromes
- Copper Ions
Which prosthetic groups carry 2 electrons?
- NADH
- FADH2
- FMN
- Coenzyme Q
- O2
What is the Electron Transport Chain?
Electrons are passed through a series of carriers found in four complexes
How do electrons move along the complexes in the ETC?
Electrons move favourably along the complexes based on Standard Reduction Potential (E’0)
What do E’0 values outline?
Outlines the tendency of a molecule to either be reduced or oxidized
- What does a negative E’0 value indicate?
- What does a positive E’0 value indicate?
- Indicates a good reducing agent (donates electrons)
- Indicates a good oxidizing agent (accepts electrons)
State:
The equation for ΔG’^0
ΔG’^0 = -nFΔE’
One NADH donor pumps – – across the membrane
10 H+
One FADH2 donor pumps - – across the membrane
6 H+
What do Electron Transport Chain Inhibitors do?
Block electron flow
State electron transport chain inhibitors for:
Complex I
- Rotenone
- Amytal
What do the electron transport chain inhibitors in Complex I do?
Inhibit the flow of electrons from the iron sulfur cluster in complex I to Coenzyme Q
State electron transport chain inhibitors for:
Complex III
Antimycin A
State electron transport chain inhibitors for:
Complex IV
- Cyanide
- Azide
- CO
State:
- How uncouplers work in the Electron Transport Chain
- Examples of uncouplers in the ETC
Disrupt the H+ gradient
* 2,4-Dinitrophenol (DNP)
* Carbonylcyanide-p-trifluoromethoxyphenylhydrazone (FCCP)
* Salicylate
How does ATP synthesis work?
The proton pumped into the intermembrane space by the ETC then moves with their concentration gradient through ATP synthase to generate ATP
What two regions does ATP synthase comprise of?
F1 and F0
Describe:
Function of F0 unit of ATP Synthase
Anchors the enzyme to the inner mitochondrial membrane
* H+ first passes through this unit
Describe:
Function of F1 unit in ATP Synthase
Peripheral part located in the mitochondrial matrix that performs the synthesis of ATP
Describe:
The structure of the F1 subunit of ATP Synthase
Alpha and Beta subunits form a cylindrical shape
* Conformational changes in the beta subunit drive ATP production
How many beta subunits are there in F1?
3
What stages do the beta-subunits of F1 rotate through?
- Open (empty)
- Loose (ADP + Pi)
- Tight (ATP)
What drives the rotation of beta subunits through their stages?
The flow of H+
How many H+ is required for ATP?
4 H+ needed per ATP
* 3 for synthesis
* 1 for export via ATP-ADP translocase
What does P/O Ratios stand for?
Phosphate/Oxygen Ratio
What is the P/O Ratio for NADH?
2.5
What is the P/O Ratio for FADH2?
1.5
What is the P.O ratio of Cytosol derived NADH?
1.5
What does cytosol derived NADH have a P/O Ratio of 1.5?
It cannot cross the inner mitochondrial membrane so it is converted to FADH2 via the glycerophosphate shuttle
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: Glucose to Glucose-6-Phosphate
- Glycolysis reactions
- -1 ATP
- -1
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: Fructose-6-Phosphate to Fructose-1,6-Biphosphate
- Glycolysis reactions
- -1 ATP
- -1
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: 2 Glyceraldehyde-3-Phosphate to 2 1,3-Biphosphoglycerate
- Glycolysis reactions
- 2 NADH
- 3 or 5
(Cytosolic NADH only produce 3 ATP)
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: 2 1,3-Bisphosphoglycerate to 2 3-Phosphoglycerate
- Glycolysis reactions
- 2 ATP
- 2
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: 2 Phosphoenolpyruvate to 2 Pyruvate
- Glycolysis reactions
- 2 ATP
- 2
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: 2 Pyruvate to 2 Acetyl-CoA
- Pyruvate Dehydrogenase Complex
- 2 NADH
- 5
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: 2 Isocitrate to 2 α-Ketoglutarate
- Citric Acid Cycle reactions
- 2 NADH
- 5
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: 2 α-Ketoglutarate to 2 Succinyl-CoA
- Citric Acid Cycle reactions
- 2 NADH
- 5
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: 2 Succinyl-CoA to 2 Succinate
- Citric Acid Cycle reactions
- 2 ATP/GTP
- 2
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: 2 Succinate to 2 Fumarate
- Citric Acid Cycle reactions
- 2 FADH2
- 3
State:
- The process that the reaction belongs to
- ATP/coenzyme produced
- Final NET ATP gain/loss
For: 2 Malate to 2 Oxaloacetate
- Citric Acid Cycle reactions
- 2 NADH
- 5
After going through glycolysis, pyruvate dehydrogenase complex, and Citric Acid Cycle, how many ATP are produced in total?
30-32
