Biochemistry
6th Edition
ISBN: 9781305577206
Author: Reginald H. Garrett, Charles M. Grisham
Publisher: Cengage Learning
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Chapter 26, Problem 16P
Interpretation Introduction
Interpretation:
Explanation about the representatives of the PRT family of enzymes in purine synthesis.
Concept introduction:
Aminoalkanoic acid and PRPP is used for the formation of 5'-phosphoribosylamine and this process is catalyzed by PRPP transaminase. Regulation of purine synthesis is done by the PRPP transaminase.
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Lysozyme is an enzyme that hydrolyzes bacterial cell wall polysaccharides. When this reaction is carried out in the presence of H218O, it is observed that there is retention of configuration at the C1 carbon of the D site sugar as shown below:
Would this result suggest that the enzyme mechanism involves the direct nucleophilic attack of water at C1 or that the enzyme mechanism involves attack by a nucleophilic amino acid side chain of the enzyme that generates a transient covalent intermediate?
Phosphoribosyltransferase (PRT) catalyzes the attachment of a salvaged purine nitrogenous base on the activated form of ribose-5-phosphate called 5-phosphoribosyl-
α
α-pyrophosphate (
α
α-PRPP).
True
Or
False
The sedimentation value of aspartate transcarbamoylase decreases when the enzyme switches to the R state. On the basis of the allosteric properties of the enzyme, explain why the sedimentation value decreases.
Chapter 26 Solutions
Biochemistry
Ch. 26 - Prob. 1PCh. 26 - Prob. 2PCh. 26 - Allosteric Regulation of Purine and Pyrimidine...Ch. 26 - Inhibition of Purine and Pyrimidine Metabolism by...Ch. 26 - Prob. 5PCh. 26 - Allosteric Regulation of Ribonucleotide Reductase...Ch. 26 - Prob. 7PCh. 26 - Prob. 8PCh. 26 - Prob. 9PCh. 26 - Prob. 10P
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