Acyl-coa dehydrogenase

Definition

Acyl-CoA dehydrogenase is an enzyme that catalyzes the first step in the β-oxidation of fatty acids, where it converts acyl-CoA into trans-Δ²-enoyl-CoA by introducing a double bond between the α and β carbon atoms. This enzyme plays a crucial role in the metabolism of fatty acids, impacting energy production through the breakdown of long-chain fatty acids into acetyl-CoA units for energy generation. The activity of acyl-CoA dehydrogenase is essential for maintaining proper energy balance in cells, particularly during periods of fasting or prolonged exercise.

5 Must Know Facts For Your Next Test

1. Acyl-CoA dehydrogenase is categorized into different isoforms based on the chain length of fatty acids it acts upon, including short-, medium-, and long-chain acyl-CoA dehydrogenases.
2. Deficiencies in acyl-CoA dehydrogenase can lead to metabolic disorders such as Medium-Chain Acyl-CoA Dehydrogenase Deficiency (MCADD), which can cause hypoglycemia and other serious health issues.
3. The enzyme is located in the mitochondrial matrix, where it plays a key role in the catabolism of fatty acids to produce energy.
4. Acyl-CoA dehydrogenase requires flavin adenine dinucleotide (FAD) as a cofactor for its activity, which is involved in the electron transfer during the reaction.
5. Inhibition or malfunction of acyl-CoA dehydrogenase can lead to an accumulation of fatty acids and their derivatives, which can be toxic to cells and disrupt normal metabolic functions.

Review Questions

• How does acyl-CoA dehydrogenase contribute to the process of β-oxidation, and what would happen if this enzyme were deficient?
  • Acyl-CoA dehydrogenase initiates β-oxidation by converting acyl-CoA into trans-Δ²-enoyl-CoA, thus enabling the continued breakdown of fatty acids for energy production. If there is a deficiency in this enzyme, it can lead to a buildup of fatty acids in the body, causing conditions like Medium-Chain Acyl-CoA Dehydrogenase Deficiency (MCADD), resulting in severe hypoglycemia and potential metabolic crisis due to impaired fat metabolism.
• Describe the significance of the cofactor FAD in the function of acyl-CoA dehydrogenase and how this relates to energy metabolism.
  • FAD is essential for acyl-CoA dehydrogenase activity as it serves as a cofactor that accepts electrons during the oxidation process. This electron transfer is crucial for converting acyl-CoA into trans-Δ²-enoyl-CoA. The involvement of FAD not only highlights how enzymes facilitate chemical reactions but also emphasizes the interconnectedness of various metabolic pathways, as this process is key for efficient energy production through fatty acid breakdown.
• Evaluate the broader implications of acyl-CoA dehydrogenase dysfunction on overall metabolic health and disease states.
  • Dysfunction in acyl-CoA dehydrogenase can have significant implications for metabolic health, leading to disorders such as MCADD, characterized by an inability to effectively oxidize medium-chain fatty acids. This can result in an energy deficit during fasting or prolonged exercise, increasing susceptibility to hypoglycemia and metabolic crises. Understanding these consequences sheds light on the importance of fatty acid metabolism in overall health and highlights potential therapeutic targets for managing such disorders.

Related terms

β-oxidation: A metabolic process that breaks down fatty acids into acetyl-CoA units, producing energy in the form of ATP.

Fatty Acids:

Carboxylic acids with long hydrocarbon chains that are important energy sources and components of lipids.

Acetyl-CoA: A central metabolite that plays a key role in various metabolic pathways, including the citric acid cycle and fatty acid synthesis.