For many eukaryotic proteins, processing by post-translational modifications such as glycosylation is a critical step for correct folding and achievement of biological activity. These modifications that occur naturally within eukaryotic cells have to be replicated when preparing peptides and proteins that are chemically synthesized or recombinantly-produced in prokaryotic cells.
This technology enables production of glycosylated peptides using a new method relying on a photocleavable auxiliary comprising a PEG attachment and a thiol group for native chemical ligation (NCL). This new auxiliary molecule combines easy attachment of a polymer (such as PEG) to a peptide for direct enzymatic modification with the ability to selectively link these modified peptide segments to form larger, complex modified polypeptides and with very mild, traceless removal of the auxiliary.