Gluconeogenesis

Question 1

Gluconeogenesis eq. hexokinase/glucokinase

Answer 1

glucose-6-phosphatase

Question 2

Phosphofructokinase-1 eq

Answer 2

fructose-1,6-bisphosphatase

Question 3

pyruvate kinase eq in mitochondria

Answer 3

pyruvate is converted to OAA via pyruvate carboxylase and requires biotin (B7)

Question 4

pyruvate kinase eq in cytoplasm

Answer 4

PEP carboxykinase

converts OAA to PEP

Question 5

Pyruvate carboxylase

Answer 5

mito enzyme 
catayzes first step in gluconeogenesis
mito pyruvate carboxylated to form OAA
CO2 and ATP dependent 
Biotin cofactor

Question 6

Phosphoenolpyruvate carboxykinase (PEPCK)

Answer 6

decarboxylation of PAA to PEP

GTP used

Question 7

Fructose 1,6-BP

Answer 7

RLS
activated by cortisol and citrate
inhibited by AMP and F26BP

Question 8

G6P

Answer 8

dephosphoform to form glucose 
only in liver, kidneys, SI and pancreas
activated by cortisol
deficiency results in Van Gierkes
located in the lumen of ER
GLUT7 transports glucose into cytoplasm

Question 9

Cori cycle

Answer 9

links the lactate produced from anaerobic glycolysis in RBC and exercising muscle to gluconeogenesis in liver
lactate in muscle –> pyruvate –> gluconeogenesis in liver and glucose goes back into the muscle

Question 10

Precursors for gluconeogenesis

Answer 10

fructose, galactose, glycerol, propionate, lactate, alanine, amino acids
carbs, lipids, protein

Question 11

Fructose 1,6-BP deficiency

Answer 11

• Similar to tarui disease in glycolysis
• Presents in infancy or early childhood
• Hypoglycemia, lactic acidosis, ketosis, apnea, hyperventilation
• Can’t digest or make fruc 16BP so send to liver for ketone body production

Question 12

Von Gierke disease

Answer 12

• Deficiency in glucose-6-phosphatase
• G6P Glucose, so always in its phosphorylated form
• Hepatomegaly is a clinical hallmark
• Hyperlipidemia