EBK ORGANIC CHEMISTRY
8th Edition
ISBN: 8220102744127
Author: Bruice
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 22.9, Problem 17P
Carboxypeptidase A has esterase activity as well as peptidase activity, so it can hydrolyze ester bonds as well as peptide bonds. When carboxypeptidase A hydrolyzes ester bonds. Glu 270 acts as a nucleophilic catalyst instead of a general-base catalyst. Propose a mechanism for the carboxypeptidase A-catalyzed hydrolysis of an ester bond.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Triosephosphate isomerase (TIM) catalyzes the conversion of dihydroxyacetone phosphate to glyceraldehyde-3-phosphate. The enzyme’s catalytic groups are Glu 165 and His 95. In the first step of the reaction, these catalytic groups function as a general-base and a general-acid catalyst, respectively. Propose a mechanism for the reaction.
lysozyme catalyzes the hydrolysis of a carbohydrate linkage in part of the bacterial wall. The active site of the lysozyme contains aspartate and glutamate side chains.
1. lysozyme catalyzes this reaction with a catalytic Zn 2+ ion. propose a mechanism.
The first step in the catabolism of most amino acids is the removal of the nitrogen atom by transfer to an a-keto acid, a reaction
catalyzed by an enzyme called a transaminase. The a-keto acid acceptor is often a-ketoglutarate. Modify the structures in the
product to show the products of the transamination of cysteine. Be sure to show functional groups with the charge and number of
attached hydrogen atoms appropriate for pH 7.4.
transaminase
+
O=C
H₂N-CH
+
CH₂
CH₂
CH₂
SH
Incorrect
H₂N
||
CH
|
CH₂
|
CH₂
I
||
O
||
n
|
CH₂
T
SH
Chapter 22 Solutions
EBK ORGANIC CHEMISTRY
Ch. 22.2 - Compare each of the mechanisms listed here with...Ch. 22.2 - Prob. 3PCh. 22.2 - Prob. 4PCh. 22.3 - a. Draw the mechanism for the following reaction...Ch. 22.5 - Prob. 7PCh. 22.5 - Propose a mechanism for the Co2+ catalyzed...Ch. 22.6 - Prob. 9PCh. 22.7 - Prob. 10PCh. 22.7 - Prob. 12PCh. 22.7 - Prob. 13P
Ch. 22.9 - Which of the following amino acid side chains can...Ch. 22.9 - Which of the following C-terminal peptide bonds is...Ch. 22.9 - Carboxypeptidase A has esterase activity as well...Ch. 22.10 - Arginine and lysine side chains fit into trypsins...Ch. 22.10 - Explain why serine proteases do not catalyze...Ch. 22.11 - If H2 18O is used in the hydrolysis reaction...Ch. 22.11 - Draw the pH-activity profile for an enzyme that...Ch. 22.12 - The pHactivity profile for glucose-6-phosphate...Ch. 22.12 - Prob. 23PCh. 22.13 - Draw the mechanism for the hydroxide ion-catalyzed...Ch. 22.13 - What advantage does the enzyme gain by forming an...Ch. 22.13 - Prob. 26PCh. 22.13 - Prob. 27PCh. 22.13 - Aldolase shows no activity if it is incubated with...Ch. 22 - Which of the following parameters would be...Ch. 22 - Prob. 29PCh. 22 - Prob. 30PCh. 22 - Prob. 31PCh. 22 - Indicate the type of catalysis that is occurring...Ch. 22 - The deuterium kinetic isotope effect (KH2O/KD2O)...Ch. 22 - Prob. 34PCh. 22 - Co2+ catalyzes the hydrolysis of the lactam shown...Ch. 22 - there are two kinds of aldolases. Class I...Ch. 22 - Prob. 37PCh. 22 - The hydrolysis of the ester shown here is...Ch. 22 - Prob. 39PCh. 22 - At pH = 12, the rate of hydrolysis of ester A is...Ch. 22 - 2-Acetoxycyclohexyl tosylate reacts with acetate...Ch. 22 - Proof that an imine was formed between aldolase...Ch. 22 - Prob. 43PCh. 22 - a. Explain why the alkyl halide shown here reacts...Ch. 22 - Triosephosphate isomerase (TIM) catalyzes the...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- Acetolactate synthase is another TPP-requiring enzyme. It transfers the acyl group of pyruvate to another molecule of pyruvate, forming acetolactate. This is the first step in the biosynthesis of the amino acids valine and leucine. Propose a mechanism for this reaction.arrow_forwardAspartame (Nutrasweet®) is a remarkably sweet-tasting dipeptide ester. Complete hydrolysis of aspartame gives phenylalanine, aspartic acid, and methanol. Mild incubation with carboxypeptidase has no effect on aspartame. Treatment ofaspartame with phenyl isothiocyanate, followed by mild hydrolysis, gives the phenylthiohydantoin of aspartic acid.Propose a structure for aspartame.arrow_forwardAcetolactate synthase is another TPP-requiring enzyme. It transfers the acyl group of pyruvate to another molecule of pyruvate, forming acetolactate. This is the first step in the biosynthesis of the amino acids valine and leucine. Propose a mechanism for this reaction.arrow_forward
- Use curved arrows to illustrate how the following decarboxylation occurs in the presence of an acid HA. This reaction constitutes one step in the biosynthesis of the amino acid tyrosine.arrow_forwardThe reaction of an ester with an amine is not as slow as the reaction of an ester with water or an alcohol. Explain with reason. Explain why the rate of aminolysis of an ester cannot be increased by H+, OH- or OR-. How can you activate the carboxylic acid? Is acid catalyzed hydrolysis of acetamide a reversible or an irreversible reaction. Explain.arrow_forwardα-Amino acids can be prepared by treating an aldehyde with ammonia/trace acid, followed by hydrogen cyanide, followed by acid-catalyzed hydrolysis. What amino acid is formed when the aldehyde that is used is 3-methylbutanal?arrow_forward
- Please draw by hand. Triosephosphate isomerase (TIM) catalyzes the conversion of dihydroxyacetone phosphate to glyceraldehyde-3-phosphate. The enzyme's catalytic groups are Glu 165 and His 95. In the first step of the reaction, these catalytic groups function as a base and an acid catalyst, respectively. Propose a mechanism for the reaction. ОН 2-03Р0 ОН dihydroxyacetone phosphate triosephosphate isomerase 2-03РО. H glyceraldehyde-3-phosphate FYI Glu is glutamic acid and his is histadinearrow_forwardThe following three derivatives of succinimide are anticonvulsants and have found use in the treatment of epilepsy, particularly petit mal seizures. Ph Ph `N' `N' ČH3 ČH3 Methsuximide Ethosuximide Phensuximide Following is a synthesis of phensuximide. CN Ph CN Ph CN 1. NaOH, H2O 2. HC, Н20 NaOEt KCN Ph-CHO cOOEt H cOOEt NC COOEt 3. Нeat Ethyl cyanoacetate (A) (B) Benzaldehyde Ph Ph Ph CH;NH2 НООС СООН Et0oC COOEt `N' (C) (D) ČH3 Phensuximide Methsuximide is formed by a similar pathway to that shown for phensuximide. Draw the structure of the compound that reacts with ethyl cyanoacetate in the synthesis of methsuximide.arrow_forwardA chemically modified guanidino group is present in cimetidine (Tagamet), a widely prescribed drug for the control of gastric acidity and peptic ulcers. Cimetidine reduces gastric acid secretion by inhibiting the interaction of histamine with gastric H2 receptors. In the development of this drug, a cyano group was added to the substituted guanidino group to alter its basicity. Do you expect this modified guanidino group to be more basic or less basic than the guanidino group of arginine? Explain.arrow_forward
- Several compounds have been found to inhibit -lactamase, and drugs based on these compounds can be taken in combination with penicillins and cephalosporins to restore their effectiveness when resistance is known to be a problem. The commonly prescribed formulation called Augmentin is a combination of the -lactamase inhibitor shown below with amoxicillin (shown above). It is used to treat childhood ear infections when resistance is suspected, and many kids know it as the white liquid that tastes like bananas. Which of the statements below are true statements? 1. The stereochemistry of the fusion between the four-and five-membered rings in the inhibitor and amoxicillin are different. 2. The inhibitor possesses enol ether and allylic alcohol functional groups while the antibiotic possesses a phenol and a secondary amide functional group. 3. Neither the inhibitor nor the antibiotic contains strained rings. 4. Both 1 and 2 are true.arrow_forwardShow how to convert the side-chain carboxyl group to a benzyl ester using benzyl chloride as a source of the benzyl group.arrow_forwardA variation of the acetamidomalonate synthesis can be used to synthesize serine. The process involves the following steps: Ethoxide ion deprotonates diethyl acetamidomalonate, forming enolate anion 1; Enolate anion 1 makes a nucleophilic attack on formaldehyde, forming tetrahedral intermediate 2; Protonation of the oxyanion forms alcohol 3; Acid hydrolysis yields dicarboxyamino alcohol 4; Decarboxylation leads to the final amino acid. Write out the mechanism on a separate sheet of paper, and then draw the structure of tetrahedral intermediate 2. You do not have to consider stereochemistry. You do not have to explicitly draw H atoms. Do not include lone pairs in your answer. They will not be considered in the grading. Draw carboxyl and amino groups in their uncharged forms.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Introduction to General, Organic and BiochemistryChemistryISBN:9781285869759Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar TorresPublisher:Cengage Learning
Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning
Introduction to General, Organic and Biochemistry
Chemistry
ISBN:9781285869759
Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar Torres
Publisher:Cengage Learning
Organic Chemistry
Chemistry
ISBN:9781305580350
Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher:Cengage Learning
DIGESTER-35 | VITAMINS AND THEIR RELATED COENZYMES| GPAT | NIPER | PHARMACIST| DI; Author: GPAT DISCUSSION CENTER;https://www.youtube.com/watch?v=CGrdNYmho0s;License: Standard YouTube License, CC-BY