Question

Select the correct product A of the above-given reaction from the four choices given below:

• A.
• B.
• C.
• D.

Answer 1

The Correct Option is D

The given reaction involves the decarboxylation of L-Histidine. This process is catalyzed by the enzyme L-histidine decarboxylase and involves the coenzyme pyridoxal phosphate (PLP).

Decarboxylation is the removal of a carboxyl group, releasing carbon dioxide (\text{CO}_2). The substrate, L-Histidine, undergoes this reaction to form histamine.

1. L-Histidine has the following structure:
   

   

2. In the presence of L-histidine decarboxylase and pyridoxal phosphate, the -\text{COOH} group is removed as carbon dioxide (\text{CO}_2).
3. The reaction results in the formation of histamine, which retains the amino group and the imidazole ring.

Among the given options, the structure of histamine is correctly represented in the following image:

This image matches the expected product of the decarboxylation of L-Histidine, confirming that histamine is the correct product.