Enzymatic peptide synthesis

The enzymatic peptide synthesis is an increasingly winning in synthetic chemistry important variant of peptide synthesis .

Basics

Due to the participation of enzymes , it has the advantages of more environmentally friendly reaction conditions as well as a high stereospecificity , whereby only L - amino acids are linked. The basic principle is the reverse of the peptide cleavage catalyzed by proteases such as trypsin and thus the use of the proteases for peptide synthesis. The prerequisite for this is the given reversibility of the protease-catalyzed reaction. The reaction equilibrium is then influenced accordingly based on the effects of the law of mass action .

Procedure

The essential principles of reversing the exergonic and thus actually preferred hydrolysis of the peptides are:

1. thermodynamic effects
   • Product accumulation: By precipitation , transferring to another phase or complexing , the peptide , which initially arises from the use of large amounts of substrate, is withdrawn from the system, so its formation is chemically preferred.
   • Approximation of the pKa values ​​of the carboxy group and the amino group by increasing the pKa value of the carboxy group in organic solvents such as DMSO
2. kinetic effects
   • Deacylation of the acyl enzyme intermediates formed in serine proteases and cysteine proteases with z. B. acylaminoalkyl esters instead of water . So a new peptide bond is formed .

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• Uni Jena: Trial of Enzymatic Peptide Synthesis (PDF file; 559 kB)