Gluconeogenesis

Question 1

Stage 1 - reactants and products, reaction type, requirements and enzyme? Where?

Answer 1

Formation of oxaloacetate by the carboxylation of pyruvate. This reaction also requires one molecule of ATP, and is catalyzed by pyruvate carboxylase.

Mitochondria

Question 2

Stage 2 - reactants and products, reaction type, requirements and enzyme? Where?

Answer 2

Oxaloacetate is reduced to malate using NADH, malate dehydrogenase.

Mitochondria

Question 3

Stage 3 - what happens?

Answer 3

Malate crosses the mitochondrial membrane into the cytoplasm

Question 4

Stage 4 - reactants and products, reaction type, requirements? Where?

Answer 4

Malate is oxidized to oxaloacetate using NAD+

Cytosol

Question 5

Stage 5 - reactants and products, reaction type, requirements and enzyme? Where?

Answer 5

Oxaloacetate is decarboxylated and then phosphorylated to form phosphoenolpyruvate using the enzyme PEPCK.

A molecule of GTP is hydrolyzed to GDP during this reaction.

Cytosol

Question 6

Stage 6 - reactants and products, enzyme?

Answer 6

Phosphoenolpyruvate -
2-phosphoglycerate

Enolase

Question 7

Stage 7 - reactants and products, enzyme?

Answer 7

2-phosphoglycerate - 3-phosphoglycerate

Phosphoglycerate mutase

Question 8

Stage 8 - reactants and products, enzyme?

Answer 8

3-phosphoglycerate - 1,3 BPG

Phosphoglycerate kinase

Question 9

Stage 9 - reactants and products, enzyme?

Answer 9

1,3 BPG - Glycerate-3-phosphate

Glyceraldehyde-3-phosphate dehydrogenase

Question 10

Stage 10 - reactants products, enzyme?

Answer 10

Glycerate-3-phosphate/ DHAP (TPI) - F1,6BP

Aldolase

Question 11

Stage 11 - reactants products, enzyme?

Answer 11

F-1,6-BP - F-6-P

F1,6-bisphosphatase

Question 12

Stage 12 - reactants products, enzyme?

Answer 12

F-6-P - G-6-P

Phosphoglucose isomerase