gluconeogenesis

Question 1

What are the four irreversible enzymes of gluconeogenesis

Answer 1

1. Pyruvate carboxylate (mito, pyruvate to OAA)
2. PEP carboxykinase (cytosol, OAA to PEP)
3. F-1,6-BPtase (cytosol, F-1,6-BP to F6P)
4. G6Ptase (ER, G6P to glucose)

“Pathway produces fresh glucose”

Question 2

What does pyruvate carboxylase require

Answer 2

• Biotin
• ATP
• activated by acetyl-CoA

Question 3

What does PEP carboxykinase require

Answer 3

GTP

Question 4

What activates F-1,6-BPtase

Answer 4

Citrate

Question 5

What inhibits F-1,6-BPtase

Answer 5

• AMP
• F-2,6-BP

Question 6

Where can you find the enzymes for gluconeogenesis

Answer 6

1. Liver mainly
2. kidney
3. intestinal epithelium

Question 7

Why can’t muscle participate in gluconeogenesis

Answer 7

lacks glucose-6-phosphatase

Question 8

Can odd-chain FA serve as glucose source

Answer 8

Yes

1. Odd chain FA yields 1 propionyl-CoA during metab
2. propionyl-CoA enters TCA as succinyl-CoA
3. undergo gluconeogenesis
4. serve as glucose source

Question 9

Why can’t even chain FA produce new glucose

Answer 9

they only yield acetyl-CoA equivalents