Application of enzymes for the synthesis of the Cholecystokinin Pentapeptide (CCK-5) A contribution to Green chemistry

The reversal of the proteolytic cleavage of the peptide bond by proteases leads to the enzymatic peptide synthesis. In contrast to the chemical synthesis enzymes form the peptide bond without the danger of racemisation. The coupling can be conducted in aqueous buffer, no hazardous chemicals are necessary. Quite often side chain protection of the amino acids can be omitted, thus simplifying the synthetic procedure. Enzymatic peptide synthesis is a very good example of green chemistry. Application of immobilised enzymes has several advantages in comparison to free enzymes in the synthesis of peptides as therapeutical drugs. Here the principles of enzymatic peptide synthesis are discussed and their application in our peptide synthetic work with immobilised enzymes is presented.