Essential Organic Chemistry, Global Edition
3rd Edition
ISBN: 9781292089034
Author: Paula Yurkanis Bruice
Publisher: PEARSON
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Chapter 19, Problem 46P
A student is trying to determine the mechanism for a reaction that uses ATP to activate a carboxylate ion, which then reacts with a thiol. If the carboxylate ion attacks the γ-phosphorus of ATP, the reaction products are the thioester, ADP, and phosphate. However, whether it attacks the α-phosphorus or the β-phosphorus of ATP cannot be determined from the reaction products because the thioester, AMP, and pyrophosphate would be the products in both reactions. The mechanisms can be distinguished by a labeling experiment in which the enzyme, the carboxylate ion, ATP, and radioactively labeled pyrophosphate are incubated, and ATP is isolated. If the isolated ATP is radioactive, attack occurred on the α-phosphorus. If it is not radioactive, then attack occurred on the β-phosphorus. Explain these conclusions.
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Chapter 19 Solutions
Essential Organic Chemistry, Global Edition
Ch. 19.4 - Prob. 1PCh. 19.4 - How many molecules of NADH are formed from the...Ch. 19.4 - Why does the OH group add to the -carbon rather...Ch. 19.5 - Prob. 4PCh. 19.5 - Prob. 5PCh. 19.5 - The oxidation of glyceraldehyde-3-phosphate to...Ch. 19.5 - Prob. 7PCh. 19.6 - Prob. 8PCh. 19.6 - Prob. 9PCh. 19.6 - Propose a mechanism for the reduction of...
Ch. 19.7 - Prob. 11PCh. 19.8 - Acid-catalyzed dehydration reactions are normally...Ch. 19.8 - Prob. 13PCh. 19.8 - Prob. 14PCh. 19.8 - Prob. 15PCh. 19.9 - Prob. 16PCh. 19.10 - a. What is the name of the enzyme that converts...Ch. 19.13 - Prob. 18PCh. 19 - Prob. 19PCh. 19 - Prob. 20PCh. 19 - Prob. 21PCh. 19 - Prob. 22PCh. 19 - Prob. 23PCh. 19 - Prob. 24PCh. 19 - Prob. 25PCh. 19 - Prob. 26PCh. 19 - Prob. 27PCh. 19 - Prob. 28PCh. 19 - Prob. 29PCh. 19 - Prob. 30PCh. 19 - Prob. 31PCh. 19 - Prob. 32PCh. 19 - Prob. 33PCh. 19 - Prob. 34PCh. 19 - Prob. 35PCh. 19 - Prob. 36PCh. 19 - Prob. 37PCh. 19 - Prob. 38PCh. 19 - Prob. 39PCh. 19 - Prob. 40PCh. 19 - Prob. 41PCh. 19 - Prob. 42PCh. 19 - Prob. 43PCh. 19 - Prob. 44PCh. 19 - UDP-galactose-4-epimerase converts UDP-galactose...Ch. 19 - A student is trying to determine the mechanism for...Ch. 19 - What would be the results of the experiment in...
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