The Edman degradation method is one of the earliest methods for determining the primary sequence ( sequencing ) of peptides. Developed in 1950-1956 by the Swedish biochemist Peer Victor Edman. The essence of the method is to process the studied peptide with a specific set of reagents, which leads to the elimination of one amino acid from the N-end of the sequence. Cyclic repetition of the reaction and analysis of reaction products provide information on the sequence of amino acids in the peptide. Edman's method was widespread in the second half of the 20th century. Currently, it is practically not used due to many inherent disadvantages (non-quantitative course of the reaction, multiple side processes).
Method
FITC ( phenylisothiocyanate ) is a reagent used to determine the N-terminal amino acid in a peptide . It is able to react with alpha amino acids and the alpha carboxyl group of free amino acids. As a result of interaction with the N-terminal amino acid of the polypeptide, a phenylthiohydanthione derivative is formed in which the bond between the alpha-carboxyl group of the N-terminal amino acid in the peptide is destabilized. This bond is selectively hydrolyzed without damaging other peptide bonds. after the reaction, a complex of FITC with an N-terminal amino acid is isolated and identified by chromatographic method. Next, this process is repeated with a shortened peptide. In this way, the amino acid sequence in the peptide is obtained.
Sources
Ovchinnikov Yu. A. Bioorganic chemistry. M., 1987 .-- S. 57.
See also
- Sanger Method