Dr Sean Meaden
BBSRC Discovery Fellow

Profile

Biography

My research is focused on the interactions between bacteria and their viruses, and the ecological and evolutionary processes that shape such interactions. My work uses a combination of experimental evolution and genomic approaches to address these topics.

I completed my PhD at the University of Exeter working with Professor Britt Koskella. The project focused on how the environment shapes the evolution of bacterial resistance in the plant pathogen Pseudomonas syringae.

After a brief post doctoral position at UC Berkeley I returned to Exeter (and microbiology) to work with Professor Edze Westra studying the ecology and evolution of the bacterial immune system, CRISPR, in the bacterial pathogen Pseudomonas aeruginosa.

In 2019, I was awarded a Marie-Skłodowska Curie Fellowship to join the lab of Professor Peter Fineran at the University of Otago, New Zealand. During this fellowship, and subsequent return phase at Exeter, I used metagenomic data to describe the environmental distribution of CRISPR across natural microbial communities.

This work forms the foundation of my BBSRC Discovery Fellowship, held at York. For my outreach work, I have used DNA sequencing methods to teach concepts in microbial ecology and worked with Phages for Global Health- a programme that delivers training in phage biology to scientists in developing countries.

Research

Overview

Bacteria possess a diverse array of immune systems with which to defence against their viruses, known as phages. They can exist in myriad combinations and are frequently mobilized horizontally. The resulting distribution of these defences is indicative of high rates of gain and loss, suggesting that ecological factors may determine when specific defences are most beneficial.

Our work seeks to understand these ecological and evolutionary drivers using a combination of experimental evolution and, more recently, metagenomic analysis of natural communities.

My current BBSRC Discovery fellowship aims to identify active phage infections in situ, using combinations of genomic analysis techinques (HiC sequencing and Nanopore). In parallel, we are characterizing the viral community and assessing the role of factors such as viral abundance and diversity in shaping bacterial defence.

The work is focused on soils due to their importance for ecosystem and plant health, as well as representing one of the most diverse microbial ecosystems on earth.