1st irreversible step
Pyruvate –> oxaloacetate
Pyruvate carboxylase
+ B7, ATP, acetyl-CoA in Mitochondria
2nd irreversible step
Oxaloacetate –> Phosphoenolpyruvate
PEP carboxykinase
+ GTP
3rd irreversible step
F-1,6-bisphosphate –> F-6-phosphate
F-1,6-bisphosphatase
+ citrate
- F-2,6-bisphosphate
4th irreversible step
G-6-P –> Glucose
glucose-6-phosphatase