Multi-TaG: Next generation bioorthogonal probes for multi-method targeted analysis of glycoproteins
1Heinrich Heine Universität Düsseldorf, Heinrich-Heine-Universität Düsseldorf, Institut für Organischeund Makromolekulare Chemie, Dusseldorf,
Glycosylation is the most prevalent posttranslational modification (PTM) that substantially affects the structure and functions of proteins. Heterogeneity and dynamic changes, make the analysis of glycoproteins very challenging, which demands for new tools and strategies. One established method is the use of metabolic labelling with non-natural functionalized sugars and subsequent covalent tagging with analytical probes by means of bioorthogonal chemistry. However, established bioorthogonal probes are often limited regarding their experimental read- out options and their applicable bioorthogonal attachment chemistry. Here, we present a strategy for the generation of bioorthogonal probes that allow the combination of multiple experiments by using only one tag that is attached to the sample of interest. Our approach uses solid phase peptide synthesis to combine multiple functional units (fluorophores, cross linkers, cleavable linkers, affinity units and isotopic labels etc.) in a building block fashion on a solid support. Using a special linker, our synthesis strategy further allows probe release and C-terminal functionalization in one step. This approach provides high flexibility regarding the bioorthogonal handle that is introduced in the final step of the synthesis. We show a library of multi-functional probes that allow smart workflows and concerted analysis of glycoproteins with different methods, such as imaging, isolation and targeted or quantitative glycoprotiomics.