Edman digestion

Edman digestion

A technique used to determine the sequence of a protein’s amino acids.

Method
A peptide of interest is treated with phenylisothiocyanate-Edman reagent, which attaches at the N-terminal residue, making the first peptide bond in the protein susceptible to digestion by a mild acid. The first amino acid is removed and determined by chemical means; repetition on up to 20–30 amino acids can be accomplished automatically by the sequencers.