Picolyl Azide-Gly-Gly-Gly

Picolyl Azide is an advanced probe for sortase mediated labeling of proteins that incorporates a copper-chelating motif to raise the effective concentration of Cu(I) at the reaction site to boost the efficiency of the CuAAC reaction, resulting in a faster and more biocompatible CuAAC labeling. Sortase catalyzes a transpeptidase reaction between a specific internal sequence of a protein and an amine group present on the N-terminus of triglycine recently has become an area of great interest. This method of labeling proteins has been denoted as “Sortagging”.

Proteins conjugated to Picolyl Azide-Gly-Gly-Gly can be further modified with alkyne- or DBCO-containing molecules creating site-specific protein conjugates. Examples of creating protein conjugates using sortagging include site-specifically PEGylating proteins,¹ site-specific protein-lipid conjugates,² and constructing peptides and glycosylphosphatidylinositol chimeras.³ Sortase has also been used in peptide synthesis to cyclize peptides to create macrocyclic peptides, glycopeptides⁴ and protein−protein conjugates.