You have a peptide with the sequence HEEDRKYYLCG. You may assume that the side-chain pKa values from the textbook are correct for the peptide. You may further assume that, for any pH more than 2 pH units away from the pKa value, the group will be fully protonated or deprotonated. a) What is the charge on the peptide at pH 1? b) What is the charge on the peptide at pH 6? c) What is the charge on the peptide at pH 12.5?

You have a peptide with the sequence HEEDRKYYLCG. You may assume that the side-chain pKa values from the textbook are correct for the peptide. You may further assume that, for any pH more than 2 pH units away from the pKa value, the group will be fully protonated or deprotonated. a) What is the charge on the peptide at pH 1? b) What is the charge on the peptide at pH 6? c) What is the charge on the peptide at pH 12.5?

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter27: Amino Acids And Proteins

Section: Chapter Questions

Problem 27.45P

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