EBK BIOCHEMISTRY
1st Edition
ISBN: 9780100659568
Author: MATHEWS
Publisher: YUZU
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Textbook Question
Chapter 2, Problem 15P
The anno acid arginine ionizes according to the following scheme:
a. Calculate the isoelectric point of arginine. You can neglect contributions from form l. Why?
b. Calculate the average charge on arginine when pH = 9.20. (Hint: Find the average charge for each ionizable group and sum these together)
c. Is the value of average charge you calculated in part b reasonable, given the pl you calculated part a? Explain your answer.
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The amino acid arginine ionizes according to the following scheme: (a) Calculate the isoelectric point of arginine. You can neglect contributionsfrom form I. Why?(b) Calculate the average charge on arginine when pH = 9.20.(c) Is the value of average charge you calculated in part b reasonable, giventhe pI you calculated in part a? Explain your answer.
The amino acid arginine ionizes according to the following scheme: (a) Calculate the isoelectric point of arginine. You can neglect contributions from form I. Why? (b) Calculate the average charge on arginine when pH = 9.20. (c) Is the value of average charge you calculated in part b reasonable, given the pI you calculated in part a? Explain your answer
For the following pentapeptides: Ser-Glu-Gly-His-Ala and Gly-His-Ala-Glu-Ser
A. Compute their isoelectric pH (pI). Show full solution. Use standard pKa values.
B. Do these peptides with the same amino acid composition have different net charges at pH 7.0? Explain briefly.
C. Would you expect the titration curves of the two peptides to differ? Why or Why not?
Chapter 2 Solutions
EBK BIOCHEMISTRY
Ch. 2 - Suppose a chloride ion and a sodium ion are...Ch. 2 - Draw two different possible hydrogen-bonding...Ch. 2 - Prob. 3PCh. 2 - 4. What is the pH of each of the following...Ch. 2 - Prob. 5PCh. 2 - The weak acid HA is 2% ionized (dissociated) in a...Ch. 2 - 7. Calculate the pH values and draw the titration...Ch. 2 - What is the pH of the following buffer mixtures?...Ch. 2 - a. Suppose you wanted to make a buffer of exactly...Ch. 2 - Prob. 10P
Ch. 2 - You need to make a buffer whose pH is 7.0, and you...Ch. 2 - Describe the preparation of 2.00 L of 100 glycine...Ch. 2 - Carbon dioxide is dissolved in blood (pH 7.4) to...Ch. 2 - What is the molecular basis for the observation...Ch. 2 - The anno acid arginine ionizes according to the...Ch. 2 - It is possible to make a buffer that functions...Ch. 2 - A student is carrying out a biological preparation...Ch. 2 - Histidine is an amino acid with three titratable...Ch. 2 - Prob. 19PCh. 2 - Prob. 20PCh. 2 - Prob. 21P
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