Assume you have a solution containing the pyruvate dehydrogenase complex and all the enzymes of the TCA cycle, but none of the metabolic intermedi- ates. When you supplement this solution with 5 umoles each of pyruvate, oxaloacetate, coenzyme A, NAD*, FAD, GDP, and P,, you find that 5 umoles of CO, are evolved and then the reaction stops. When you add alcohol dehy- drogenase and its substrate acetaldehyde, additional CO, is produced. (a) How do you explain this result? (b) How many umoles of acetaldehyde are required to allow complete oxida- tion of the pyruvate to 15 umoles of CO,?

Assume you have a solution containing the pyruvate dehydrogenase complex and all the enzymes of the TCA cycle, but none of the metabolic intermedi- ates. When you supplement this solution with 5 umoles each of pyruvate, oxaloacetate, coenzyme A, NAD*, FAD, GDP, and P,, you find that 5 umoles of CO, are evolved and then the reaction stops. When you add alcohol dehy- drogenase and its substrate acetaldehyde, additional CO, is produced. (a) How do you explain this result? (b) How many umoles of acetaldehyde are required to allow complete oxida- tion of the pyruvate to 15 umoles of CO,?

Chemistry for Today: General, Organic, and Biochemistry

9th Edition

ISBN:9781305960060

Author:Spencer L. Seager, Michael R. Slabaugh, Maren S. Hansen

Publisher:Spencer L. Seager, Michael R. Slabaugh, Maren S. Hansen

Chapter23: Carbohydrate Metabolism

Section: Chapter Questions

Problem 23.66E: Lactate dehydrogenase catalyzes the following equilibrium reaction in both liver and muscle cells:...

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