5. Based on your understanding of allosteric regulation and using terminology related to the allosteric (MWC) model, explain how the enzyme glycogen phosphorylase is affected by the binding of AMP and what affect this binding would have on the overall activity of the enzyme. Predict what would happen to the activity of the enzyme when glycogen phosphorylase is covalently modified and there are high levels of ATP in the cell.

5. Based on your understanding of allosteric regulation and using terminology related to the allosteric (MWC) model, explain how the enzyme glycogen phosphorylase is affected by the binding of AMP and what affect this binding would have on the overall activity of the enzyme. Predict what would happen to the activity of the enzyme when glycogen phosphorylase is covalently modified and there are high levels of ATP in the cell.

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter18: Glycolysis

Section: Chapter Questions

Problem 21P

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(d) of glucose oxidation in diabetic human patients treated with Metformin (●) and in (nondiabetic) control human patients (0). At –150 min both groups of subjects were started on an intravenous feed of 3-(®H)-glucose, and at t = 0 min they were started on an oral glucose tolerance test whereby a measured amount of glucose in water (a syrupy mixture) was swallowed followed by measure- ment of blood glucose levels at 30 min intervals. The flux of glucose oxidation was measured by the appear- ance of 3H2O in the blood stream. While the information The diagram to the right compares the rate 8000 ORAL GLUCOSE 6000- 4000- 2000- -120 -60 60 120 180 240 300 Minutes cannot be directly extracted from the reaction mecha- nism diagrams in the textbook, the glycolytic step in which the tritium is first released into water is that catalyzed by TPI, as illustrated at the beginning of Question #3. Explain why this step is suitable for measuring the flux of glycolysis through the release of °H…
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Select a property that does not belong to allosteric enzymes. They conform to hyperbolic Michaelis-Menten kinetics They may have binding sites for regulatory molecules that are separate from active sites They tend to have a signmoidal curve of rate versus [S] They undergo conformation changes as a result of modulator binding.