Fundamentals of General, Organic, and Biological Chemistry (8th Edition)
8th Edition
ISBN: 9780134015187
Author: John E. McMurry, David S. Ballantine, Carl A. Hoeger, Virginia E. Peterson
Publisher: PEARSON
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Textbook Question
Chapter 19, Problem 19.52AP
How do you explain the observation that pepsin, a digestive enzyme found in the stomach, has a high catalytic activity at pH 1.5, while trypsin, an enzyme of the small intestine, has no activity at pH 1.5?
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When enzyme solutions are heated, there is a progressive loss of catalytic activity over time due to denaturation of the enzyme. A solution of the enzyme hexokinase incubated at 450C lost 50% of its activity in 12 minutes, but when incubated at 450C in the presence of a very large concentration of one of its substrates, it lost only 3% of its activity in 12 minutes. Suggest why thermal denaturation of hexokinase was retarded in the presence of one substrates
When enzyme solutions are heated, there is a progressive loss of catalytic activity over time due to denaturation of the enzyme. A solution of the enzyme hexokinase incubated at 45 °C lost 50% of its activity in 12 min, but when incubated at 45 °C in the presence of a very large concentration of one of its substrates, it lost only 3% of its activity in 12 min. Suggest why thermal denaturation of hexokinase was retarded in the presence of one of its substrates.
A multi-enzyme complex Is made up of three polypeptide chains, A, B and C. A is
associated with decarboxylase activity; B is a transacetylase, while C is a
dehydrogenase. When the protein was placed in a nonpolar solvent, then run in
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transacetylase and dehydrogenase activities. When the protein was also placed
in an aqueous solvent at pH 5.0, then run in electrophoresis, two protein bands
were also detected. Further enzyme assays also showed that one protein band
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Chapter 19 Solutions
Fundamentals of General, Organic, and Biological Chemistry (8th Edition)
Ch. 19.1 - Prob. 19.1PCh. 19.1 - The enzyme LDH converts lactate to pyruvate. In...Ch. 19.2 - The cofactors NAD+, Cu2+, Zn2+, coenzyme A, FAD,...Ch. 19.3 - Describe the reactions that you would expect these...Ch. 19.3 - Prob. 19.5PCh. 19.3 - Prob. 19.6PCh. 19.3 - Prob. 19.7PCh. 19.3 - Prob. 19.8PCh. 19.4 - Prob. 19.9KCPCh. 19.5 - Prob. 19.10KCP
Ch. 19.5 - Prob. 19.11PCh. 19.5 - Prob. 19.12PCh. 19.6 - Prob. 19.13PCh. 19.6 - Prob. 19.14PCh. 19.7 - (a) L-Threonine is converted to L-isoleucine in a...Ch. 19.8 - AZT (zidovudine) inhibits the synthesis of the HIV...Ch. 19.8 - Prob. 19.3CIAPCh. 19.8 - Prob. 19.16PCh. 19.9 - Does the enzyme described in each of the following...Ch. 19.9 - Prob. 19.18PCh. 19.9 - Compare the structures of vitamin A and vitamin C....Ch. 19.9 - Prob. 19.20PCh. 19.9 - Prob. 19.21KCPCh. 19.9 - Prob. 19.22PCh. 19.9 - Prob. 19.4CIAPCh. 19.9 - Prob. 19.6CIAPCh. 19.9 - Prob. 19.7CIAPCh. 19.9 - Enzyme levels in blood are often elevated in...Ch. 19.9 - Prob. 19.9CIAPCh. 19.9 - Prob. 19.23PCh. 19 - Prob. 19.24UKCCh. 19 - Prob. 19.25UKCCh. 19 - Prob. 19.26UKCCh. 19 - Prob. 19.27UKCCh. 19 - Prob. 19.28APCh. 19 - Explain how the following mechanisms regulate...Ch. 19 - Prob. 19.30APCh. 19 - Prob. 19.31APCh. 19 - Prob. 19.32APCh. 19 - Prob. 19.33APCh. 19 - Prob. 19.34APCh. 19 - Prob. 19.35APCh. 19 - Prob. 19.36APCh. 19 - Prob. 19.37APCh. 19 - Name an enzyme that acts on each molecule. (a)...Ch. 19 - Name an enzyme that acts on each molecule. (a)...Ch. 19 - What features of enzymes make them so specific in...Ch. 19 - Describe in general terms how enzymes act as...Ch. 19 - Prob. 19.42APCh. 19 - Prob. 19.43APCh. 19 - Prob. 19.44APCh. 19 - Prob. 19.45APCh. 19 - Prob. 19.46APCh. 19 - Prob. 19.47APCh. 19 - What is the difference between the lock-and-key...Ch. 19 - Why is the induced-fit model a more likely model...Ch. 19 - Prob. 19.50APCh. 19 - Prob. 19.51APCh. 19 - How do you explain the observation that pepsin, a...Ch. 19 - Prob. 19.53APCh. 19 - Prob. 19.54APCh. 19 - Prob. 19.55APCh. 19 - Prob. 19.56APCh. 19 - Prob. 19.57APCh. 19 - The text discusses three forms of enzyme...Ch. 19 - Prob. 19.59APCh. 19 - Prob. 19.60APCh. 19 - Prob. 19.62APCh. 19 - Prob. 19.63APCh. 19 - The meat tenderizer used in cooking is primarily...Ch. 19 - Prob. 19.65APCh. 19 - Why do allosteric enzymes have two types of...Ch. 19 - Prob. 19.67APCh. 19 - Prob. 19.68APCh. 19 - Prob. 19.69APCh. 19 - Prob. 19.70APCh. 19 - Prob. 19.71APCh. 19 - Prob. 19.72APCh. 19 - Prob. 19.73APCh. 19 - Prob. 19.74APCh. 19 - Prob. 19.75APCh. 19 - Prob. 19.76APCh. 19 - Prob. 19.77APCh. 19 - Prob. 19.78APCh. 19 - Prob. 19.79APCh. 19 - Prob. 19.80CPCh. 19 - Prob. 19.81CPCh. 19 - Prob. 19.82CPCh. 19 - Prob. 19.83CPCh. 19 - Prob. 19.84CPCh. 19 - Prob. 19.85CPCh. 19 - Prob. 19.86CPCh. 19 - Prob. 19.87CPCh. 19 - Prob. 19.88GPCh. 19 - The ability to change a selected amino acid...Ch. 19 - Prob. 19.90GPCh. 19 - Prob. 19.91GP
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biochemistry and related others by exploring similar questions and additional content below.Similar questions
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