Lecture 6 Chapter 17 Glycolysis Part 2

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Lecture 6Chapter 17 Glycolysis Part 2

• Finish glycolysis
• Regulation
• What happens after?

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Types of reactions

• Mutase moves a group from one C to
• another.

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Phosphoglyceromutase
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Enolase
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High energy bond
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Pyruvate kinase
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pyruvate
Substrate level phosphorylation
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Energetics
Phosphoenolpyruvate ? Pyruvate Pi
DGo -14.8 kcal/mole
ADP Pi ? ATP
DGo 7.3 kcal/mole
Phosphoenolpyruvate ADP ? Pyruvate ATP
DGo - 7.5 kcal/mole
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ATP Summary
-1 ATP
2 ATP net
- 1 ATP
2 NADH
2 ATP
Fig. 14.10
2 ATP
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Glucose G-6-P F-6-P F-1,6-bisP
-1 ATP -1 ATP
ATP balance
NET 2 ATP
DHAP 3PGAald
1,3-bisPglycerate
3-Pglycerate 2-Pglycerate
PEP
pyrauvate.
2 ATP 2 ATP
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Glucose G-6-P F-6-P F-1,6-bisP
Energy-rich Electrons NADH
DHAP 3PGAald
1,3-bisPglycerate
3-Pglycerate 2-Pglycerate
PEP
pyrauvate.
2 NADH
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• Regulation
• Why?

2. Where? At a point where a substrate is
committed to a pathway At an
irreversible step

• What inhibits?
• Products
• ATP, glucose 6-P

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Glucose G-6-P F-6-P F-1,6-bisP
Hexokinase Glucose-6-P
Phosphofructokinase ATP
DHAP 3PGAald
1,3-bisPglycerate
3-Pglycerate 2-Pglycerate
PEP
pyrauvate.
Pyruvate kinase
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Pyruvate can participate in several different
pathways a. Aerobic respiration which
produced many molecules of ATP b.
Anaerobic alcohol fermentation with the
production of 2 ethanol, 3 carbon
dioxide and 2 ATP b. Anaerobic glycolysis
(or lactate fermentation) with the
production of 2 molecules of lactate
and 2 ATP.
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Glucose Metabolism
Glucose (6C) 2 Pyruvate (3C)
2ATP
2NADH
Glycolysis
4ATP
2ATP
2 ATP
6CO2
8NADH 2FADH2
Ethanol CO2
Lactate (3C)
Anaerobic glycolysis
2ATP
Anaerobic alcohol Fermentation
Aerobic Respiration
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Lactic Acid Fermentation- Anaerobic Glycolysis
Lactate dehydrogenase
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Energy Balance
Conversion of glucose to pyruvate produces
2ATP
2 NADH
Conversion of pyruvate to lactate requires 2
NADH
Net in lactate production 2ATP only
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Alcohol fermentation
Pyruvate ? acetaldehyde CO2
Pyruvate decarboxylase
Acetaldehyde NADH H? ethanol NAD
Alcohol dehydrogenase
Net (glucose?ethanol) 2 ATP
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Energetics
Glucose? Lactate 2ATP -14.6 kcal/mol

Glucose? Pyruvate 2ATP 2NADH -29.5
Glucose? Oxygen 38 ATP -277 kcal