Structure and function of bacterial transporters

The catalysed movement of chemicals across bacterial cell membranes is essential for their growth and competitiveness  in vivo in the human host. For bacteria that colonise mucosal surfaces the ability to acquire host-derived nutrients is both important for bacterial growth and also immune evasion in some cases.

One theme of Professor Thomas’s research focuses on how bacteria acquire sialic acids from the host, which are normally the terminal sugars on host glycans and hence readily accessible to pathogenic bacteria. Within some pathogens like Haemophilus influenzae and Vibrio cholerae a particular transporter called a tripartite ATP-independent periplasmic (TRAP) transporter is essential for this process, which has been discovered and studied heavily in the lab, while in other pathogens like Salmonella enterica subsp. Enterica Serovar Typhimurium a different transporter is used. In contrast commensal bacteria in the gut like the Ruminococcus sp. use different transporters again, work done in collaboration with Professor Nathalie Juge at the Quadram Institute, Norwich, UK. One main theme of the lab is to study the diversity of sialic acid acquisition in human pathogens and commensals and in collaboration with Professor Gregor Hageluekenat the University of Bonn, to continue to study the structure and function of TRAP transporters.