Glycobiology of host-microbe interactions at the mucosal interface

Nathalie Juge, Quadram Institute Bioscience, Norwich Research Park, UK

Hosts: Angelina Palma and Ana Luísa Carvalho, UCIBIO, NOVA

ZOOM link: https://ucibio.pt/l/GuestSeminars

Abstract:

The gut microbiota plays a major role in human physiology and an alteration in the microbiota structure and function has profound implications in health and disease.  Complex carbohydrates from the diet are the main modulators of the gut microbiota structure and function. In addition, in the colon, host mucin glycans provide sites of attachment and nutrients to the microbial communities inhabiting the mucus layer with sialic acid being a major carbohydrate epitope and a target for bacteria.

In this presentation, I will give examples of how host mucin glycans but also microbial glycans influence gut microbe-host interactions at the mucosal interface. A major focus will be on  Ruminococcus gnavus,  a prevalent human gut symbiont part of the normal gut microbiota and  disproportionately represented in intra and extra-intestinal diseases. Using a combination of molecular microbiology, biochemical  and structural approaches, we deciphered the strategy of adaptation of R. gnavus to the intestinal mucus niche, uncovering a novel sialic acid metabolic pathway in gut bacteria.

Short Bio:

Nathalie is a Group Leader at the Quadram Institute Bioscience (QIB) in Norwich (UK),  Deputy Chief Scientific Officer of the Institute, and honorary Professor at the University of East Anglia (UEA), Norwich, UK). NJ started her career working on plant and microbial carbohydrate-active enzymes, especially starch-degrading enzymes (from her PhD thesis in Marseille-France and successive post-docs at Carlsberg Institute -Copenhagen Denmark- and Institute of Food Research (FR)-Norwich UK on barley-a-amylases and fungal  glucoamylases), she then moved back to Marseille where she was appointed as lecturer and developed her Group on glycosidases and inhibitors of glycosidases. She then spent 9 years at IFR on secondment where she led a research group on plant cell degrading enzymes, working in particular on xylanases and inhibitor of xylanases (coordination of EU project on glycosidase inhibitors).  Since joining IFR (now QIB) as a Group Leader, NJ leads a Research Team that investigates glycobiology of gut microbiota-host interactions in human health and disease. The main activity of her group is on defining how gut bacteria adapt to the intestinal mucosal environment and the role of host (mucin), dietary or microbial glycans in this process.