Please review GOLDEN RICE by Aaron Brown (Kotzebue, AK)

Turn in a review sheet (2 pts; due Monday 11/13/00) .

Quiz on Monday, 11/6/00: Quiz will cover all lectures since last exam except this one.

1. Know why the citric acid cycle (also known as the tricarboxylic acid cycle and the Kreb’s cycle) is considered the "hub" of cellular metabolism. (because it oxidizes acetyl groups from many sources, not just pyruvate).
2. Know the role of the pyruvate dehydrogenase complex in feeding acetyl CoA into the citric acid cycle; the advantages of a multienzyme complex and how pyruvate decarboxylase is regulated (product inhibition by NADH and acetyl CoA; and covalent modification of E1 via pyruvate dehydrogenase kinase and pyruvate dehyrogenase phosphatase). Note similarities between pyruvate dehydrogenase complex and the a -ketoglutarate dehydrogenase complex.
3. Know that the citric acid cycle occurs in mitochondria. All citric acid cycle enzymes, except succinate dehyrogenase are in the mitochondrial matrix. Succinate dehyrdogenase is an integral membrane protein in the inner mitochondrial membrane.
4. Know that the citric acid cycle accepts 2 carbons from acetyl CoA which combine with oxaloacetic acid to form citric acid and are ultimately oxidized to 2CO₂ molecules. The citric acid cycle generates reduced coenzymes (NADH and FADH₂) that carry e^- to the electron transport chain and regenerates oxaloacetic acid. Each cycle spits out 3 NADH, 2 FADH₂, 2 molecules of CO₂, and a GTP. Because it runs in a circle, regenerating oxaloacetic acid at the completion of each round, it can oxidize an unlimited number of acetyl groups.
5. For all 8 reactions, know names of reactants and products; identity of functional groups lost, added or oxidized; and name and classification of enzyme that catalyzes the reaction. (Go to http://www.expasy.ch/enzyme/ to find classification of enzyme).
6. Identify substrate level phosphorylation in the citric acid cycle.
7. Irreversible reactions: Identify "far from equilibrium" reactions in the citric acid cycle and the enzymes that catalyze these reactions.
8. Know the role of reduced coenzymes NADH and FADH₂ (free energy of oxidation of the acetyl group is conserved in reduced coenzymes. ATP is formed when the four pairs of electrons are eventually transferred to O₂; i.e., reduced coenzymes produced in the citric acid cycle carry electrons to electron transport chain).
9. Citric acid cycle intermediates are precursors for the biosynthesis of other compounds (e.g., oxaloacetate for gluconeogenesis, a -ketoglutarate for glutamate)