Biochemistry
6th Edition
ISBN: 9781305577206
Author: Reginald H. Garrett, Charles M. Grisham
Publisher: Cengage Learning
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Chapter 18, Problem 18P
Distinguishing the Mechanisms of Class I and Class I Aldolases
Fructose bisphosphate aldolase in animal muscle is a class 1 aldolase, which forms a Schiff base intermediate between substrate (for example. fructose-1, 6-bisphosphate or dihydroxyacetone phosphate) and a lysine at the active site (see Figure I8.12). The chemical evidence for this intermediate conies from studies with aldolase and the reducing agent sodium borohydride, NaBH4. Incubation of the enzyme with dihydroxyacetone phosphate and NaBH4 inactivates the enzyme. Interestingly, no inactivation is observed if NabH4 is added to the enzyme in the absence of substrate. Write a mechanism that explains these observations and provides evidence for the formation of a Schiff base intermediate in the aldolase reaction.
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Chapter 18 Solutions
Biochemistry
Ch. 18 - Characterizing Glycolysis List the reactions of...Ch. 18 - Radiotracer Labeling of Pyruvate from Glucose...Ch. 18 - Effects of Changing Metabolite Concentrations on...Ch. 18 - Prob. 4PCh. 18 - Prob. 5PCh. 18 - The Reactions and Meehanisms of the Leloir Pathway...Ch. 18 - The Effect of lodoacetic Acid on the...Ch. 18 - Prob. 8PCh. 18 - Comparing Glycolysis Entry Points for Sucrose...Ch. 18 - Prob. 10P
Ch. 18 - Prob. 11PCh. 18 - Prob. 12PCh. 18 - Prob. 13PCh. 18 - Energetic of Fructose-1 ,6-bis P Hydrolysis...Ch. 18 - Prob. 15PCh. 18 - Energetics of the Hexokinase Reaction The...Ch. 18 - Prob. 17PCh. 18 - Distinguishing the Mechanisms of Class I and Class...Ch. 18 - Prob. 19PCh. 18 - Understanding the Mechanism of Hemolytic Anemia...Ch. 18 - Prob. 21PCh. 18 - Based on your residing of this chapter, what would...Ch. 18 - Examine the ActiveModel for alcohol dehydrogenase...Ch. 18 - Based on your knowledge of the structure of NAD+...Ch. 18 - Using the ActiveModel for phosphofructokinase...
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