Fundamentals of Biochemistry: Life at the Molecular Level
5th Edition
ISBN: 9781118918401
Author: Donald Voet, Judith G. Voet, Charlotte W. Pratt
Publisher: WILEY
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Chapter 4, Problem 22CQ
(a)
Summary Introduction
To determine: The net charge at neutral pH of a tripeptide containing only alanine.
Concept introduction: Each amino acid has unique ionization characteristics that vary at different pH levels. Ionizable groups such as amino group and carboxylic group, at certain pH levels, remain protonated, and when the pH increases, they become deprotonated.
(b)
Summary Introduction
To determine: How the total number of negative and positive charges changes, following the hydrolysis of the tripeptide containing only alanine.
Concept introduction: Each amino acid has unique ionization characteristics that vary at different pH levels. Ionizable groups such as amino group and carboxylic group at certain pH levels remain protonated, and when the pH increases, they become deprotonated.
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Chapter 4 Solutions
Fundamentals of Biochemistry: Life at the Molecular Level
Ch. 4 - Prob. 1ECh. 4 - 2. Glutamate, a 5-carbon amino acid, is the...Ch. 4 - Prob. 3ECh. 4 - Prob. 4ECh. 4 - 5. Draw the dipeptide Asp-His at pH 7.0.
Ch. 4 - 6. Calculate the number of possible pentapeptides...Ch. 4 - 7. Identify the hydrogen bond donor and acceptor...Ch. 4 - 8. In some proteins, the side chain of serine...Ch. 4 - 9. Determine the net charge of the predominant...Ch. 4 - 10. Determine the net charge of the predominant...
Ch. 4 - Prob. 11ECh. 4 - 12. Circle the chiral carbons in the following...Ch. 4 - Prob. 13ECh. 4 - 14. Patients with Parkinson’s disease are...Ch. 4 - 15. Over time, the glutamine residues of...Ch. 4 - 16. Some hormone-signaling pathways result in the...Ch. 4 - 17. Which amino acids have side chains that are...Ch. 4 - 18. Draw the structure of Lys and Ala linked by an...Ch. 4 - 19. Some bacteria produce poly-?-glutamic acid, a...Ch. 4 - Prob. 20ECh. 4 - 21. A sample of the amino acid tyrosine is barely...Ch. 4 - Prob. 22CQCh. 4 - 23. Calculate the pI of (a) Ala, (b) His, and (c)...Ch. 4 - Prob. 24CQCh. 4 - 25. Draw the peptide ATLDAK. (a) Calculate its...Ch. 4 - 26. The protein insulin consists of two...Ch. 4 - Prob. 27CQCh. 4 - 28. The two C?H atoms of Gly are said to be...Ch. 4 - Prob. 29CQCh. 4 - Prob. 30CQCh. 4 - 31. Identify the amino acid residue front which...Ch. 4 - Prob. 32CQCh. 4 - Prob. 33CQCh. 4 - Prob. 34CQCh. 4 - Prob. 1MTE
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