Gluconeogenesis Flashcards
Where does gluconeogenesis take place in mammals?
The liver.
Define the Cori cycle.
Lactate formed by active muscle is converted into glucose by the liver.
Lactate + _____ —> _____ + NADH + _____
Lactate + NAD+ —> pyruvate + NADH + H+
State three precursors of glucose which use the enzymes of gluconeogenesis.
- Lactate.
- Glycerol.
- Amino acids.
What enzyme is used in the conversion of pyruvate to oxaloacetate?
Pyruvate carboxylase.
Pyruvate + _____ + ATP —> _____ + _____ + Pi + 2H+
Pyruvate + HCO3- + ATP —> oxaloacetate + ADP + Pi + 2H+
What is the allosteric activator for pyruvate carboxylase?
Acetyl-CoA.
How is oxalaecetate transported from the mitochondria into the cytoplasm?
It undegoes decarboxylation and phosphorylation by pyruvate carboxylase and PEP carboxykinase.
Oxaloacetate + _____ —> _____ + GDP + _____
Oxaloacetate + GTP —> PEP + GDP + CO2
The conversion of fructose-1,6-bisphosphate undergoes what type of irreversible reaction?
Irreversible hydrolysis.
Where is glucose-6-phosphate only found?
In tissues that will regulate glucose homeostasis.
What is the purpose of gluconeogenesis?
Transformation of substrates into glucose.
