Disputation: Chris Hadjineophytou
PhD candidate Chris Hadjineophytou at the Department of Biosciences will be defending the thesis "Protein glycosylation in the genus Neisseria: coordinated evolution of glycan biosynthesis and substrate targeting" for the degree of Philosophiae Doctor.
The disputation will be live streamed using Zoom. The host of the session will moderate the technicalities while the chair of the defence will moderate the disputation.
Ex auditorio questions: The chair of the defence will invite the audience to ask ex auditorio questions either written or oral. This can be requested by clicking "Participants" followed by clicking "Raise hand".
The meeting opens for participation just before 1.15 PM, and closes for new participants approximately 15 minutes after the defense has begun.
Post translational modification of proteins in bacteria and its relevance to virulence
Main research findings
Cells from all life forms produce many proteins that are decorated with various sugars (i.e., glycans) in a process called protein glycosylation. Despite its universal nature, the biological significance of protein glycosylation in bacteria is poorly understood. In many bacterial species, the majority of the glycosylated proteins (i.e., glycoproteins) are located at the cell surface. This suggests that glycans may influence how disease-causing bacteria interact with their hosts, and therefore can be exploited as targets for the development of therapeutics.
In this thesis, Chris Hadjineophytou studies bacterial protein glycosylation using species from the genus Neisseria as a model system. Comparative studies in the genus showed that a subset of neisserial species have undergone a dramatic shift in protein glycosylation genes to utilize phase variable galactose glycans. This shift was strictly associated with species that can glycosylate their Type IV pilin subunits, which are abundant surface-exposed proteins required for colonization. Furthermore, this work identified the underlying factors that determine pilin glycosylation in the genus. Overall, the findings presented in this thesis provide an insight into the evolution and function of protein glycosylation in Neisseria, as well as other bacterial systems in general.