University of Dundee

“All the World’s a Phage” – Exploring phage-host interactions

Event Date: 
Wednesday, November 20, 2019 - 12:30
Event Location: 
School of Life Sciences, Sir Kenneth and Lady Noreen Murray Seminar Room
Professor Nicola Stanley-Wall FRSE FRSB FEAM
Event Speaker: 
Dr Tim Blower
Durham University
Event Type: 

Bacteriophages (phages) outnumber bacteria by ten to one, with an estimated 1030 phages causing infections at a rate of 1025 a second. This huge selection pressure drives diversity of the global microbiome, and phage-mediated horizontal gene transfer disseminates traits such as antimicrobial resistance between hosts. This pressure has also led to the development of bacterial systems that protect from phage predation. Many of these phage-resistance systems have already proved useful to biochemists: the restriction-modification, abortive infection and CRISPR-Cas systems underpinned the recombinant DNA and genome editing revolutions. Exploring new phage-resistance mechanisms may uncover novel tools for biomedical research, and will improve our understanding of phage-bacteria interactions. This may prove increasingly important as phage therapy becomes a more viable strategy to treat antibiotic-resistant infections. We have isolated a ten-gene phage-defence island from a multidrug-resistant plasmid of Escherichia fergusonii and demonstrated that it encodes an active BacteRiophage EXclusion (BREX) locus and a single-chain type IV restriction enzyme, active against a wide-range of tested coliphages. We are exploring the biochemistry and structure of the BREX and restriction enzyme components.