III. Gluconeogenesis
The Cori Cycle

Irreversible Steps of Glycolysis

1.
Pyruvate Carboxylase

2.
Phosphoenolpyruvate Carboxykinase
3.
Fructose 1,6-BisphosphataseFructose 1,6-BisP + H2O ---> Fructose 6-P + Pi
4.
Glucose 6-PhosphataseGlucose 6-P + H2O ---> Glucose + Pi
Bypass Reactions of Gluconeogenesis Part III
Glycolysis
, Glucose ---> 2 Pyruvate:Glucose + 2 ADP + 2 Pi + 2 NAD+ --->
2 Pyruvate + 2 ATP + 2 NADH + 2 H+ + 2 H2O
D
G° = -20 kcal/mol
Gluconeogenesis, 2 Pyruvate ---> Glucose:
2 Pyruvate + 4 ATP + 2 GTP + 2 NADH + 6 H2O --->
Glucose + 4 ADP + 2 GDP + 6 Pi + 2 NAD+ + 2 H+
D
G° = -9 kcal/mol

