Fat Metabolism

beta-Oxidation of Fatty Acids:

• What is the first step?
  • Where does it take place?
  • What is the energy product of this step?
  • What are oxidizing agents for beta-oxidation?
  • "Mainline Sequence."
  • How are AcCoA groups cleaved off? (Claisen cleavage.)
  • How many turns of beta-oxidation to convert a fatty acid to AcCoA?
• Where do the reactions of beta-oxidation take place?
  • Which step controls the rate?
  • Would you say that the breakdown of short chain fatty acids is uncontrolled? Explain.
  • Explain/describe:
    • Carnitine shuttle.
• Be able to calculate energy yield from the complete or partial oxidation of a given fatty acid.
  • Compare to glucose.

Calculations of P/O ratios

Calculate the P/O ratio (ATPs produced for each oxygen atom consumed) for the aerobic catabolism of glucose in mammalian fast twitch muscle. Show all work in a table such as we have used in class. KEY

Do this calculation again for glucose in insect flight muscle. KEY

• Why should this difference exist? (That is, why should evolution favor this lower value of energy for insect flicht muscle?)

Fatty Acid Oxidation

Calculate the P/O ratio for the aerobic catabolism of stearate (C=18). Show all work in a table such as we have used in class. KEY