Reason behind the formation of acetone containing 18 O when enzymatic decarboxylation of acetoacetate is carried out in H 2 18 O has to be stated. Concept introduction: Decarboxylation of acetoacetate is initiated by an enzyme named acetoacetate decarboxylase. Enzyme forms protonate imine with substrate acetoacetate. It loses carbon dioxide in presence of a H 2 18 O to form an enamine. The reaction proceeds further and undergoes hydrolysis to regenerate the enzyme.

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Chapter 18.21, Problem 46P

Interpretation Introduction

Interpretation: Reason behind the formation of acetone containing 18O when enzymatic decarboxylation of acetoacetate is carried out in H218O has to be stated.

Concept introduction: Decarboxylation of acetoacetate is initiated by an enzyme named acetoacetate decarboxylase. Enzyme forms protonate imine with substrate acetoacetate. It loses carbon dioxide in presence of a H218O to form an enamine. The reaction proceeds further and undergoes hydrolysis to regenerate the enzyme.

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