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CHAPTER 5. LIPID METABOLISM
INTERNATIONAL UNIVERSITY
SCHOOL OF BIOTECHNOLOGY
BIOCHEMISTRY
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Learning objectives
1. Describe the metabolism of fatty acids.
2. The two main components of fatty acid metabolism
are β oxidation and fatty acid synthesis.
3. Understand that the fatty-acid breakdown reactions
of β oxidation result in the formation of reduced
cofactors and acetyl-CoA molecules, which can be
further catabolized to release free energy.
4. Understand that the oxidation of unsaturated, odd-
chain, and very-long-chain fatty acids requires
additional enzymes, some of them in peroxisomes.
5. Understand how fatty acid synthesis resembles and
differs from β oxidation.
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Content
1. Fatty acid activation
2. Steps of β oxidation
3. Energy yield of oxidation
4. Oxidation of palmitate
5. Unsaturated fatty acids
6. Odd-chain fatty acids
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Content
7. Very long-chain fatty acids
8. Synthesis vs. oxidation
9. Steps of synthesis
10. Palmitate synthesis
11. Fatty acid synthases
Conclusion
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Fatty Acid Metabolism
LEARNING OBJECTIVES
Fatty acids are an important energy source, for they yield over
twice as much energy as an equal mass of carbohydrate or
protein. In humans, the primary dietary source of fatty acids is
triacylglycerols. This lecture will describe the metabolism of fatty
acids. The two main components of fatty acid metabolism are β
oxidation and fatty acid synthesis. Upon completion of this lecture,
you will understand that the fatty-acid breakdown reactions of β
oxidation result in the formation of reduced cofactors and acetyl-
CoA molecules, which can be further catabolized to release free
energy. You will also understand that the oxidation of unsaturated,
odd-chain, and very-long-chain fatty acids requires additional
enzymes, some of them in peroxisomes. In addition, you will
understand how fatty acid synthesis resembles and differs from β
oxidation.