L12: Amino Acid Metabolism

Question 1

Classification of amino acids

Answer 1

1. Nonpolar, aliphatic (Glycine, Alanine, Proline (cyclic ring, secondary amino group), Valine, Leucine, Isoleucine)
2. Polar uncharged (Asparagine, Threonine (-OH), Glutamine, Serine (-OH))
3. Basic: +ve charged (Lysine, Arginine, Histidine)
4. Acidic: -ve charged (Aspartate, Glutamate)
5. Aromatic (Phenylalanine, Tyrosine, Tryptophan)
6. Sulphur-containing (Methionine, Cysteine)

Question 2

***Metabolic fate of amino acids

Answer 2

1. Protein
2. Become Acetyl-CoA, fed into TCA cycle to produce ATP
3. Glucose (carbon skeleton of glucogenic a.a.: Tyrosine, Phenylalanine, Isoleucine)
4. Ketone bodies (carbon skeleton of ketogenic a.a.: Tyrosine, Phenylalanine, Isoleucine)
5. Nitrogen-containing compound
   - glutathione
   - creatine phosphate
   - monoamine neurotransmitter e.g. dopamine, noradrenaline, adrenaline, serotonin

Question 3

10 essential amino acids

Answer 3

These Ten Valuable Aminoacids Have Long Preserved Life In Men:

Threonine, Tryptophan, Valine, Arginine, Histidine, Lysine, Phenylalanine, Leucine, Isoleucine, Methionine