A peptide is sequenced using Edman degradation and HPLC. If the first peak corresponds to aspartic acid, what does this indicate about the peptide sequence?

• A. Aspartic acid is not part of the peptide sequence.
• B. Aspartic acid is at the C-terminal end of the peptide.
• C. Aspartic acid is in the middle of the peptide sequence.
• D. Aspartic acid is at the N-terminal end of the peptide.

Answer: (D)