Methylmalonyl-CoA

Methylmalonyl-CoA is a molecule that plays a crucial role in human metabolism. It is involved in the breakdown and use of proteins and fats in the body. Methylmalonyl-CoA is converted into succinyl-CoA, a key component of the citric acid cycle, through a reaction catalyzed by the enzyme methylmalonyl-CoA mutase.

Structure and Function

Methylmalonyl-CoA is a derivative of coenzyme A, a molecule that is essential for many biochemical reactions in the body. The structure of methylmalonyl-CoA includes a carboxyl group, a thiol group, and a methyl group, which are attached to a ribose sugar and an adenine base.

The primary function of methylmalonyl-CoA is to facilitate the breakdown of certain amino acids and fatty acids. This process is crucial for the production of energy in the body.

Role in Metabolism

In the process of metabolism, methylmalonyl-CoA is converted into succinyl-CoA, a molecule that is a key component of the citric acid cycle. This conversion is catalyzed by the enzyme methylmalonyl-CoA mutase, which requires vitamin B12 (cobalamin) as a cofactor.

If there is a deficiency of methylmalonyl-CoA mutase or vitamin B12, the conversion of methylmalonyl-CoA to succinyl-CoA is impaired. This can lead to a buildup of methylmalonyl-CoA and related compounds in the body, a condition known as methylmalonic acidemia.

Methylmalonic Acidemia

Methylmalonic acidemia is a rare genetic disorder that affects the body's ability to break down certain proteins and fats. Symptoms can include vomiting, dehydration, weakness, and developmental delay. Treatment typically involves a low-protein diet and supplements of vitamin B12.

See Also

• Coenzyme A
• Citric acid cycle
• Methylmalonyl-CoA mutase
• Vitamin B12
• Methylmalonic acidemia