Biochemistry: Concepts and Connections (2nd Edition)
2nd Edition
ISBN: 9780134641621
Author: Dean R. Appling, Spencer J. Anthony-Cahill, Christopher K. Mathews
Publisher: PEARSON
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Chapter 3, Problem 15P
The major difference between a protein molecule in its native state and in its denatured state lies in the number of conformations available. To a first approximation, the native, folded state can be thought to have one conformation. The unfolded state can be estimated to have three possible orientations about each bond between residues.
a. For a protein of 100 residues, estimate the entropy change per mole upon denaturation.
b. What must be the enthalpy change accompanying denaturation to allow the protein to be half-denatured at
50o C?
c. WiII the fraction denatured increase or decrease with increasing temperature?
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The major difference between a protein molecule in its native state and in its
denatured state lies in the number of conformations available. To a first ap-
proximation, the native, folded state can be thought to have one conforma-
tion. The unfolded state can be estimated to have three possible orientations
about cach bond between residues.
(a) For a protein of 100 residues, estimate the entropy change per mole upon
denaturation.
(b) What must be the enthalpy change accompanying denaturation to allow
the protein to be half-denatured at 50 °C?
(c) Will the fraction denatured increase or decrease with increasing
temperature?
The major difference between a protein molecule in its native state and inits denatured state lies in the number of conformations available. To a firstapproximation, the native, folded state can be thought to have one conformation. The unfolded state can be estimated to have three possible orientations about each bond between residues.(a) For a protein of 100 residues, estimate the entropy change per moleupon denaturation.(b) What must be the enthalpy change accompanying denaturation to allow the protein to be half-denatured at 50 °C?(c) Will the fraction denatured increase or decrease with increasingtemperature?
Using the data in Table calculate the average amino acid residue weight in a protein of typical composition. This is a useful number to know for approximate calculations
Chapter 3 Solutions
Biochemistry: Concepts and Connections (2nd Edition)
Ch. 3 - Prob. 1PCh. 3 - Given the following reactions and their...Ch. 3 - The decomposition of crystalline N2O5...Ch. 3 - The oxidation of glucose to CO2 and water is a...Ch. 3 - Prob. 5PCh. 3 - In another key reaction in glycolysis,...Ch. 3 - Assume that some protein molecule, in its folded...Ch. 3 - When a hydrophobic substance like a hydrocarbon is...Ch. 3 - It is observed that as temperature is increased,...Ch. 3 - Suppose a reaction has Ho and So values...
Ch. 3 - Prob. 11PCh. 3 - Prob. 12PCh. 3 - Prob. 13PCh. 3 - Undergoing moderate activity, an average person...Ch. 3 - The major difference between a protein molecule in...Ch. 3 - Prob. 16PCh. 3 - Prob. 17PCh. 3 - Consider the degradation of glucose to pyruvate by...Ch. 3 - a. Consider the malate dehydrogenase reaction,...Ch. 3 - Bovine ribonuclease folds with Ho = -280 kJmol-1...
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