Q29-40E - Organic Chemistry (Mcmurry)

Question

What enzyme cofactor is associated with each of the following kinds of reactions?

(a) Transamination

(b) Carboxylation of a ketone

(c) Decarboxylation of an  $\mathit{\alpha }\mathbf{-}\mathbf{\text{keto acid }}$

Step-by-Step Solution

Answer

(a) The enzyme cofactor is pyridoxal phosphate.

(b) The enzyme cofactor is biotin.

(c) The enzyme cofactor is thiamin diphosphate.

Step 1: (a) Find the enzyme cofactor associated with the transamination reaction.

The enzyme cofactor associated with transamination reactions is pyridoxal phosphate as shown below:

Step 2: (b) Identify the enzyme cofactor associated with carboxylation of a ketone reaction.

The enzyme cofactor associated with carboxylation of a ketone reaction is biotin as shown below:

Step 3: (c) Enzyme cofactor associated with decarboxylation of an α - keto acid 

The enzyme cofactor associated with decarboxylation of an reaction is thiamin diphosphate as shown below: