EP ESSENTIAL ORG.CHEM.-MOD.MASTERING
3rd Edition
ISBN: 9780133858501
Author: Bruice
Publisher: PEARSON CO
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Chapter 18.11, Problem 25P
Explain why the ability of PLP to catalyze an amino acid transformation is greatly reduced if a PLP requiring enzymatic reaction is carried out at a pH at which the pyridine nitrogen is not protonated.
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Explain why the rate of aminolysis of an ester cannot be increased by H+, HO-, or RO-.
α-Amino acids can be prepared by treating an aldehyde with ammonia/trace acid, followed by hydrogen cyanide, followed by acid-catalyzed hydrolysis.
Draw the structures of the two intermediates formed in this reaction.
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.
Chapter 18 Solutions
EP ESSENTIAL ORG.CHEM.-MOD.MASTERING
Ch. 18.1 - Prob. 1PCh. 18.2 - If H218O were used to hydrolyze lysozyme, which...Ch. 18.3 - Which of the following amino acid side chains can...Ch. 18.3 - Arginine and lysine side chains fit into trypsins...Ch. 18.4 - Which of the following amino acid side chains can...Ch. 18.4 - Prob. 6PCh. 18.5 - Prob. 7PCh. 18.5 - Draw the mechanism for the hydroxide-ion-catalyzed...Ch. 18.5 - What advantage does the enzyme gain by forming an...Ch. 18.7 - Prob. 10P
Ch. 18.7 - Prob. 11PCh. 18.8 - How many conjugated double bonds are there in a....Ch. 18.8 - Instead of adding to the 4a-position and...Ch. 18.8 - In succinate dehydrogenase, FAD is covalently...Ch. 18.8 - Prob. 15PCh. 18.9 - Acetolactate synthase is another TPP-requiring...Ch. 18.9 - Acetolactate synthase can also transfer the acyl...Ch. 18.9 - Prob. 18PCh. 18.9 - Prob. 19PCh. 18.10 - Prob. 21PCh. 18.11 - Prob. 23PCh. 18.11 - Which compound is more easily decarboxylated?Ch. 18.11 - Explain why the ability of PLP to catalyze an...Ch. 18.11 - Explain why the ability of PLP to catalyze an...Ch. 18.12 - What groups are interchanged in the following...Ch. 18.13 - Why is the coenzyme called tetrahydrofolate?Ch. 18.13 - What amino acid is formed by the following...Ch. 18.13 - How do the structures of tetrahydrofolate and...Ch. 18.13 - What is the source of the methyl group in...Ch. 18 - Prob. 32PCh. 18 - Prob. 33PCh. 18 - From what vitamins are the following coenzymes...Ch. 18 - Prob. 35PCh. 18 - For each of the following reaction, name both the...Ch. 18 - Explain why serine proteases do not catalyze...Ch. 18 - Prob. 38PCh. 18 - For each of the following enzyme catalyzed...Ch. 18 - Trisephosphate isomerase (TIM) catalyzes the...Ch. 18 - Prob. 41PCh. 18 - What acyl groups have we seen transferred by...Ch. 18 - When UMP is dissolved in T2O, exchange of T for H...Ch. 18 - Prob. 44PCh. 18 - When transaminated, the three branched-chain amino...Ch. 18 - Aldolase shows no activity if it is incubated with...
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