C-Terminal Activation by Lipase

Nuijens et al. explored the use of subtilisin cross-linked enzyme aggregates and lipase for the activation of amino acids and peptides to obtain acyl donors for coupling reactions. This included amidation [104], and conversion to esters by attachment of the carboxamidomethyl (Cam) or trifluoroethyl (Tfe) group [11-13]. Interestingly, the esters could be formed and coupled to peptides by the same alcalase. Ester synthesis could also be catalyzed by lipase (CalB), and esterification and peptide bond formation could be catalyzed in the same reaction mixture. In these coupled reactions, the best results were obtained with a mixture of CalB and subtilisin. 

15 DISCOVERY AND ENGINEERING OF ENZYMES FOR PEPTIDE SYNTHESIS AND ACTIVATION 

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