Question

Malate and not oxaloacetate is transported across the inner mitochondrial membrane. Rationalize why the transport of malate is critical for gluconeogenesis from amino acids.

Optional: use amino acid biodegradation products to come up with an answer.

Answer 1

Gluconeogenesis from amino acids happens when the glucose stores are depleted and the carbon skeleton to carry out the process of energy production is derived from amino acid degradation and this process of gluconeogenesis.One such product of the biodegradation of amino acids is oxaloacetate.

Now oxaloacetate which is an important part in the process cannot pass the inner mitochondrial membrane as it lacks transporters and therefore it is reduced into makati in the mitochondrion and is transported to cytosol  for gluconeogenesis to occur where malate  is again to oxaloacetate in cytosol