Notes for chapter 17, pages 607-
Unsaturated fatty acids require two additional enzymes. What are they? What reactions do these enzymes catalyze? Why doesn't Enoyl-CoA hydratase just add water to the double bond in 16:1? Is the energy yeild from the complete oxidation of 16:1 significantly different from the energy yeild from the complete oxidation of 16:0?
Fatty acids with an odd number of carbons require three additional enzymes for complete oxidation to carbon dioxide and water. What is the end product of beta oxidation of 17:0? What are the three additional enzymes that are needed to metabolize this end product? You should look at homework problems 13 and 17 now.
Dorothy Crowfoot Hodgkin determined the structure of vitamin B12 in 1956. What technique did she use to do this? Why is B12 often called cyanocobalamine? Does its structure in the test tube differ from its structure in the cell? Why don't plants have this vitamin? What is pernicious anemia, what causes it, and how is it treated? You should look at homework problem 19 now.
Methylmalonic acidemia is due to a genetic defect in methylmalonyl-CoA mutase. The symptoms mimic ethylene glycol poisioning: vomiting, coma, death and this disease was misdiagnosed as ethylene glycol poisoning in an infamous case in Missourie. Supposedly, labs found ethylene glycol in the bottle of milk that had been given to the baby. As biochemistry students, you should be able to recognize that the two molecules are remarkably different. How could this mistake have occured?
Regulation of b-oxidation is controlled by the inhibition of Carnitine Transferase I by malonyl CoA. When are levels of malonyl CoA high? Why is this a good regulatory molecule? Two other enzymes of b-oxidation are regulated, what are they and what regulated them?
Odds and Ends: Be aware of what goes on inside peroxisomes. How is the oxidation of fatty acids different in the peroxisomes? What are the final products? What does catalase do?
The liver and kidney endoplasmic reticulum has enzymes that oxidize fatty acids. What are these enzymes and what are the resulting products? Where do these products go?
What is the most common genetic defect in fat metabolism among northern Europeans? What are the symptoms? How are these patients treated?
Ketone bodies include: acetone, D-b-hydroxybutyrate and acetoacetate. When are these made? Where do they go? How are they used as fuels? What conditions can lead to an overproduction of these ketones? How do these conditions cause these excesses of ketones? Why is Diabetes similar to starvation?
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