Site-selective chemoenzymatic construction of synthetic glycoproteins using endoglycosidases
Fernández-González M., Boutureira O., Bernardes GJL., Chalker JM., Young MA., Errey JC., Davis BG.
Combined chemical tagging followed by Endo-A catalysed elongation allows access to homogeneous, elaborated glycoproteins. A survey of different linkages and sugars demonstrated not only that unnatural linkages can be tolerated but they can provide insight into the scope of Endo-A transglycosylation activity. S-linked GlcNAc-glycoproteins are useful substrates for Endo-A extensions and display enhanced stability to hydrolysis at exposed sites. O-CH 2-triazole-linked GlcNAc-glycoproteins derived from azidohomoalanine-tagged protein precursors were found to be optimal at sterically demanding sites. © The Royal Society of Chemistry.