Professor Bruce Turnbull

Talk: Re-engineering bacterial toxins for new activities

Cell surface glycans are exploited by many bacteria and viruses as receptors for cell targeting and entry. Bacterial toxins such as cholera toxin have evolved architectures that enable them to cluster membrane glycolipids, generating curvature that drives endocytosis. In this talk, I will describe our strategies for re-engineering the architecture and composition of the cholera toxin to create non-toxic analogues with new functionalities. We show that simple architectural changes — achieved through site-specific chemical functionalisation or genetic fusion of coiled coil motifs — can transform a membrane bending protein into a membrane fusogen. Using a wide range of biophysical techniques, we probe how these structural modifications give rise to emergent behaviours such as vesicle fusion and nanoscale assembly. I will also discuss repurposing CTB as a neuronal tracer and protein delivery platform, and present our development of hybrid toxin constructs as potential therapeutics for chronic pain.

About this speaker

Professor Bruce Turnbull is a chemist whose research focuses on re-engineering biological systems for novel applications at the interface of chemistry and biology. After gaining his BSc in Chemistry (1995) from the University of St Andrews and PhD in carbohydrate chemistry (1998), working with Professor Rob Field, Bruce undertook postdoctoral research as a Wellcome Trust International Prize Travelling Research Fellow at UCLA with Sir Fraser Stoddart. He used the return leg of his Wellcome fellowship to join Prof Steve Homans in the Astbury Centre at the University of Leeds, where he has now worked for the past 25 years. He joined the School of Chemistry as a Lecturer in 2004, held a Royal Society University Research Fellowship from 2005 to 2013, and became Professor of Biomolecular Chemistry in 2016.

Bruce’s research develops chemical and enzymatic methods to modify carbohydrates and proteins for applications in targeted delivery and engineering biology. He has led two European networks and a Royal Society conference on Synthetic Glycobiology. His current work includes re-engineering bacterial toxins for intracellular delivery, designing glycopolymers for wrapping biological surfaces, creating superselective probes for neurons and cancer cells, and developing glycan microarrays with fluorinated glycans to dissect protein-glycan interactions. His interdisciplinary research has been recognised through the Royal Society of Chemistry Carbohydrate Award (2013) and the Bader Award (2024). He represents the UK on the EuChemS Division of Glycoscience and the European Carbohydrate Organisation, and will host EUROCARB XXIII at the University of Leeds in 2027.