Image Based Question-65515

With help of the drug shown below, serotonin is synthesized from which of the following precursor amino acid?

A. Tyrosine.

B. Tryptophan.

C. Phenylalanine.

D. Glycine.

Correct Answer » B Explanation

Ans:B. Tryptophan.

• Serotonin is synthesized from the essential amino acid tryptophan.
• The rate-limiting step is the conversion of the amino acid to 5-hydroxytrptophan by tryptophan hydroxylase.
• This is then converted to serotonin by the aromatic L-amino acid decarboxylase which needs Pyridoxal Phosphate as a cofactor.