Enoyl-coa hydratase

Definition

Enoyl-CoA hydratase is an enzyme that catalyzes the hydration of enoyl-CoA intermediates during the β-oxidation of fatty acids. This reaction converts an enoyl-CoA into a 3-hydroxyacyl-CoA by adding a water molecule, facilitating the breakdown of fatty acids for energy production. The role of this enzyme is crucial in enabling cells to efficiently utilize fatty acids, especially during periods of fasting or increased energy demand.

5 Must Know Facts For Your Next Test

1. Enoyl-CoA hydratase plays a vital role in the second step of the β-oxidation cycle, following the formation of enoyl-CoA from acyl-CoA.
2. The enzyme works by adding water across the double bond of enoyl-CoA, which is critical for continuing the breakdown of fatty acids.
3. This hydration reaction results in the formation of 3-hydroxyacyl-CoA, which is then further processed in subsequent steps of β-oxidation.
4. Enoyl-CoA hydratase exists in different isoforms in various tissues, reflecting its importance in energy metabolism and adaptability to energy needs.
5. Deficiencies or dysfunctions in enoyl-CoA hydratase can lead to metabolic disorders characterized by impaired fatty acid metabolism.

Review Questions

• What is the role of enoyl-CoA hydratase in the β-oxidation pathway and how does it contribute to fatty acid metabolism?
  • Enoyl-CoA hydratase catalyzes the hydration of enoyl-CoA, transforming it into 3-hydroxyacyl-CoA during β-oxidation. This step is essential for continuing the metabolic process that breaks down fatty acids into acetyl-CoA for energy production. Without this enzyme, the efficiency of fatty acid degradation would be significantly reduced, impacting energy availability during fasting or high-energy demand situations.
• Discuss how the activity of enoyl-CoA hydratase might be influenced by physiological conditions such as fasting or exercise.
  • During fasting or intense exercise, energy demands increase, leading to heightened fatty acid oxidation as a primary energy source. Enoyl-CoA hydratase activity can be upregulated under these conditions to facilitate efficient breakdown of stored fatty acids. Enhanced enzymatic activity allows cells to quickly convert enoyl-CoA into 3-hydroxyacyl-CoA, optimizing energy yield from lipid reserves and ensuring that sufficient ATP is generated for cellular functions.
• Evaluate the potential consequences of mutations in the gene coding for enoyl-CoA hydratase on overall metabolic health.
  • Mutations in the gene coding for enoyl-CoA hydratase can lead to impaired enzyme function, disrupting normal β-oxidation processes. This can result in an accumulation of fatty acids and associated intermediates, leading to metabolic disorders such as hypoglycemia or lipid accumulation diseases. Such disturbances can have far-reaching effects on overall metabolic health, including reduced energy production and increased risk for conditions like obesity and insulin resistance, thereby highlighting the importance of this enzyme in maintaining metabolic balance.

Related terms

β-oxidation: The metabolic process by which fatty acids are broken down in the mitochondria to generate acetyl-CoA, NADH, and FADH₂ for energy production.

Acyl-CoA: A molecule formed when a fatty acid is activated by binding to coenzyme A, serving as a substrate in various metabolic pathways, including β-oxidation.

3-hydroxyacyl-CoA dehydrogenase: An enzyme that acts on 3-hydroxyacyl-CoA, converting it into ketoacyl-CoA while producing NADH, and is a subsequent step in the β-oxidation pathway.