Question

A tri-peptide is three linked amino acids where the peptide bond is formed by a dehydration

reaction. Imagine you have a tri-peptide composed of (N terminus) cysteine, phenylalanine, and

aspartic acid (C terminus).

1)Draw this tripeptide in the fully protonated state.

2)How many acidic protons are present? Identify them.

3)How many equivalence points would you expect from a titration with this peptide? Draw the predominant form of the peptide at each equivalence point.