ABSTRACT: The field of glycoscience is emerging as a frontier area both for advancing basic physiology but also for the development of innovative therapeutic interventions. Across all kingdoms of life, the surface of all cells is covered by a layer of complex glycosylated molecules, which are proving critical for intercellular signaling, cellular adhesion and regulation of the immune response. Inside the cell, the glycosylation state of proteins and lipids is controlled by a complex network of glycan-processing enzymes. Alteration of glycosylation and glycan recognition is a hallmark of numerous monogenic and chronic human diseases. In this presentation, I will discuss the design of fluorescence-quenched substrate probes for live cell monitoring of glycosidase activity. This novel class of chemical probes relies on the generation of a glyco-bis-acetal motif that undergoes spontaneous breakdown upon enzymatic hydrolysis of the glycosidic bond. I will present the synthesis of these chemical tools and their application in live cells and disease models using high-content imaging. I will also introduce our research at UdeM, focusing on the development of chemical biology strategies to capture glycan-protein interactions.
BIO: Samy Cecioni has joined the Department of Chemistry as an Assistant Professor at the Université de Montréal in 2019. He completed his PhD studies in his native France, working on multivalent inhibitors of glycan-lectin interactions. He split his time between a glycochemistry lab (Université de Lyon, Prof. Vidal) and a glycobiology lab (CNRS – Grenoble, Prof. Imberty). He then joined the lab of Prof. Vocadlo at Simon Fraser University to work on chemical glycobiology approaches geared towards eukaryotic glycosylation. As a CIHR-postdoctoral fellow, he pioneered the development of bis-acetal-based substrate probes for monitoring glycosidase activity in live cells.