Bio101/Chem111 Homework Problems #2 1. Draw the peptide KTQHV, write the sequence using 3-letter abbreviation for the amino acids, and identify: a. The N- and C-termini. b. Every a-carbon of the sequence, by labeling them with "a". c. All peptide bonds. d. Hydrogen bond donors and acceptors in the polar side chains. e. Covalent bonds that correspond to the backbone phi (D) and psi (4) angles f. Ionizable R-groups of amino acids in this sequence (circle them). i. Choose one ionizable group and draw it at pH 1, pH 7, and pH 14 and indicate the approximate net charge at each pH. ii. What fraction of His residues are charged at pH=5.8?

Bio101/Chem111 Homework Problems #2 1. Draw the peptide KTQHV, write the sequence using 3-letter abbreviation for the amino acids, and identify: a. The N- and C-termini. b. Every a-carbon of the sequence, by labeling them with "a". c. All peptide bonds. d. Hydrogen bond donors and acceptors in the polar side chains. e. Covalent bonds that correspond to the backbone phi (D) and psi (4) angles f. Ionizable R-groups of amino acids in this sequence (circle them). i. Choose one ionizable group and draw it at pH 1, pH 7, and pH 14 and indicate the approximate net charge at each pH. ii. What fraction of His residues are charged at pH=5.8?

General, Organic, and Biological Chemistry

7th Edition

ISBN:9781285853918

Author:H. Stephen Stoker

Publisher:H. Stephen Stoker

Chapter20: Proteins

Section: Chapter Questions

Problem 20.58EP: For the tripeptide SerValMet a. What amino acid is located at the peptides N-terminal end? b. What...

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