Biochemistry
6th Edition
ISBN: 9781305577206
Author: Reginald H. Garrett, Charles M. Grisham
Publisher: Cengage Learning
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Chapter 26, Problem 17P
Interpretation Introduction
Interpretation:
Explanation about the structure of DHFR reductase.
Concept introduction:
In the hydrophobic region, the parallel sheets are connected by crossover structures with helices and random coils that make an open pocket. The amino acid residue of dihydrofolate is that the surface of the macromolecule and is exposed to the solvent.
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#1 Specify the role each of the following amino acids play within the crystal structure and/or active site for Be as specific as possible, with pictures (and mechanistic arrows) as necessary. His11
Arg140
Glu89
Trp68
#2 Provide a step-wise mechanism for the reaction Bisphosphoglycerate mutase catalyzes, using the amino acids responsible for aiding in catalysis. You do not need to add surrounding amino acids that aid in substrate specificity. (drawn out)
What is the catalytic efficiency of Catalase ?
Table. The values of KM and kcat for some Enzymes and Substrates
Enzyme
Carbonic anhydrase
Substrate
CO2
HCO3
KM (M)
1.2 x 10-2
2.6 x 10-2
Kcat (s-1)
1.0 x 106
4.0 x 105
Catalase
H2O2
2.5 x 10-2
1.0 x 107
Urease
Urea
2.5 x 10-2
4.0 x 105
O A. 4 x 108 M-s-1
O B. 4 x 108 M-1.s-1
OC25x 10-9 M-s1
D. 2.5 x 102 M-1.s-1
OE 1.0 x 107 s1
Please see the attached image.
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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