Fatty acid synthesis

Definition

Fatty acid synthesis is the metabolic process through which fatty acids are created from acetyl-CoA and malonyl-CoA, primarily occurring in the liver and adipose tissue. This process is essential for the production of lipids that serve as energy stores and structural components of cell membranes. The synthesized fatty acids can be further elongated or desaturated to form various types of lipids needed for cellular functions.

5 Must Know Facts For Your Next Test

1. Fatty acid synthesis primarily occurs in the cytoplasm of liver and adipose cells, using acetyl-CoA as a precursor.
2. The process involves several enzymatic steps and is catalyzed by the fatty acid synthase complex, which combines multiple reactions into one multifunctional protein.
3. NADPH is the main reducing agent used during fatty acid synthesis, providing the necessary electrons for reduction reactions.
4. Insulin stimulates fatty acid synthesis by promoting the expression of enzymes involved in this pathway, especially after carbohydrate-rich meals.
5. Saturated and unsaturated fatty acids can be synthesized through this pathway, with the degree of saturation influenced by the presence of specific enzymes.

Review Questions

• How do acetyl-CoA and malonyl-CoA contribute to the process of fatty acid synthesis?
  • Acetyl-CoA serves as the starting material for fatty acid synthesis, providing a two-carbon unit that is added to the growing fatty acid chain. Malonyl-CoA acts as a crucial building block that donates additional two-carbon units during the elongation process. Together, they participate in a series of reactions catalyzed by the fatty acid synthase complex, leading to the formation of long-chain fatty acids.
• Discuss the role of insulin in regulating fatty acid synthesis and how it impacts energy storage in the body.
  • Insulin plays a significant role in regulating fatty acid synthesis by enhancing the activity of key enzymes involved in this metabolic pathway. After carbohydrate-rich meals, insulin levels rise, signaling cells to take up glucose and convert it into acetyl-CoA. This promotes increased fatty acid synthesis and subsequent storage as triglycerides in adipose tissue, thus facilitating energy storage in the form of lipids when excess energy is available.
• Evaluate how disruptions in fatty acid synthesis can impact overall lipid metabolism and health.
  • Disruptions in fatty acid synthesis can lead to various health issues, including metabolic disorders such as obesity and insulin resistance. When this process is impaired, it can result in an imbalance between lipid accumulation and breakdown, leading to conditions like non-alcoholic fatty liver disease or cardiovascular diseases. Furthermore, abnormal fatty acid profiles can disrupt cell membrane integrity and function, affecting cellular communication and overall metabolism, highlighting the importance of proper regulation of this biosynthetic pathway.

Related terms

Acetyl-CoA: A central metabolite that acts as a building block for fatty acid synthesis and is derived from carbohydrates, fats, and proteins.

Malonyl-CoA: A two-carbon compound derived from acetyl-CoA, which is a key substrate in the elongation of fatty acids during synthesis.

Lipid metabolism: The biochemical processes involved in the synthesis and degradation of lipids in the body, including fatty acid synthesis, breakdown, and storage.