UPR 5301

Daniel Marquez-Martin thesis defense on March, 16th 2021

Daniel Marquez-Martin from Cermav-UPR5301 and SyMMES- UMR5819 laboratories will defend his thesis entitled: "Versatile biosensor for deciphering glycoenzymatic activities". Click on the title for more information.


“To date, glycosyltransferases (GTs) are an essential family of enzymes poorly characterized both structurally and mechanistically which is being a major bottleneck in Glycoscience. These enzymes play a crucial role in living organisms, catalysing the stereo- and regiospecific transfer of an activated donor sugar to an acceptor moiety to build up complex oligosaccharides onto the cell surface. New analytical tools are required to screen enzyme-glycan interactions in high-throughput manner. In this context, Surface Plasmon Resonance imaging (SPRi) has spread as a versatile methodology to overcome this lack in the glycoscience field, for ligands screening and biomolecular interaction monitoring in a real time and without any labels.

Therefore, this multidisciplinary research project is organized in three main axes:  first, we address the heterologous expression and purification of a fucosyltransferase from the plant Arabidopsis thaliana (AtFUT1) that participates in the last step in the biosynthesis of xyloglucan (XyG) ligand. Then, specific on-surface immobilization approaches motivate the design of chemoselective strategies to conjugate XyG building-blocks to DNA scaffolds in good yields. The versatility of having ODN structures conjugated to glycans provides powerful insights for glycan purification, characterization and on-surface immobilization. Finally, the third axis is dedicated towards the conception and construction of a versatile XyG glycochip for its specific immobilization approach by DNA-Directed Immobilization (DDI). This strategy is envisioned through the powerful SPRi technique that allows the simultaneous visualization and characterization of biomolecular interactions in real time measurements, without using any label.”