Support Materials:

•  Goal
  To know and characterize the structure / function relationships of lipids and membranes.
  Be sure to answer the questions about Lorenzo's Oil and the disease Adrenoleukodystrophy (ALD).
  - see below
   
•  Objectives:
  Students will be able to...
  • write the structure of a fatty acid at physiological pH, given its symbol notation, such as 18:2^D9,12 - see Table 7.2.
  • write the symbol notation for a fatty acid, given its structure.
  • identify, given the structure or symbol notation of a fatty acid, whether it is saturated, monounsaturated, or polyunsaturated.
  • identify whether an unsaturated fatty acid, given its structure or symbol notation, is w-3,  w-6, or w-9. (w is the Greek letter omega).
  • identify, given the structure of an unsaturated fatty acid, whether a double bond is "cis" or "trans".
  • recognize that the "cis" configuration occurs in naturally occurring fatty acids and that the "trans" configuration results from industrial partial hydrogenation of vegetable oil, as in the preparation of margarines.
  • know that trans fatty acids in the diet correlates with higher serum levels of low density lipoprotein (LDL) cholesterol (so-called "bad" cholesterol) and that this is correlated with increased risk of cardiovascular disease (CVD) - see p. 203 textbook.
  • explain why 18:2^D9,11 is an example of a fatty acid containing conjugated double bonds.
  • explain the structure of a micelle (p.36, textbook) and the role of hydrophobic interaction.
  • explain, based on chemical structure, why some triglycerides are oils (liquids) at room temperature and why others are fats (solids).
     
• Web Links:
   
  • Lorenzo's Oil (Exam 4).
    
    Use the linked article on "Lorenzo's Oil" to respond to the following study questions:
    • Adrenoleukodystrophy (ALD) is due to higher-than-normal levels of very long chain saturated fatty acids, or VLCSFA's. These elevated levels of VLCSFA's, in a mechanism that is unknown, lead to a breakdown in the myelin sheath of CNS (Central Nervous System) cells. [Sounds a little bit like MS, doesn't it? ALD, however, is not associated with arg to cit conversion in myelin basic protein.]
      How many carbon atoms are found in VLCSFA's? Do these fatty acids have double bonds?
    • ALD results from a defect in a transport protein. In which part of the cell is this transporter protein found? Why does the defect in the transport protein lead to ALD? In other words, can you explain why the defect leads to an increase in VLCSFA levels in CNS cells? (These elevated levels of VLCSFA's spill into the blood plasma of ALD patients. This is the usual clinical marker for the disease.)
    • How would you classify the transport protein that is linked to ALD? Is it an example of a "pump" protein - one that requires ATP -, or does it just facilitate diffusion?
    • An oil was used in the movie "Lorenzo's oil" to treat ALD. What is the composition of Lorenzo's oil?
    • Is Lorenzo's oil an effective treatment for ALD? Click here for an answer.

  The following links are FYI only. Exam 4 will not test you on this material.

  • Click here to learn more about Lorenzo and his parents.
  • Adrenoleukodystrophy.
    A web site on peroxisomal defects from the lab of Stephen Gould at John Hopkins University of Medicine.
  • Lipoproteins.
    by Dr. Michael King at Indiana University School of Medicine.
  • Hyperlipidemia - means too much lipid.
    from the Department of Medicinal Chemistry at Virginia Commonwealth University in Richmond, VA. This site has diagrams for a lipoprotein and for lipid transport.