Josie’s project investigated how bacteria evolve to use and control viral defense systems that they acquire through horizontal gene transfer, and was co-supervised by Edze Westra and Tiffany Taylor (University of Bath). Josie’s model system is the transfer CRISPR-Cas systems and it is used to explore how naive hosts newly acquiring this system co-evolve with their phage and regulate CRISPR to provide a selective advantage. Twitter: @Ellijos
Iolanda Domingues –Post-doctoral Fellow
Iolanda’s PhD research (Evolutionary Biology, University of Lisbon) focused on the ecology and evolution of indirect antibiotic resistance, mediated by conjugative plasmids. In the Westra lab, Iolanda studied CRISPR-mediated choosiness of bacteria and specifically conditions in which a bacterial host can a selectively associate with certain mobile genetic elements, while resisting others.
Iolanda is currently an Experimental Officer with the Exeter Centre for Cytomics (EXCC) exploring the use of flow cytometry for microbiology.
Rafael da Silva Custodio – Post-doctoral Fellow
Rafael is interested in microbe-microbe interactions and human pathogen evolution and ecology in polymicrobial environments. In the Westra lab, he worked on the interspecific interactions between lung pathogens and how they drive the evolution of CRISPR-based immunity against bacteriophages in the pathogen Pseudomonas aeruginosa. Rafael has now joined the ISSD lab at the i3S (Portugal) and will be studying the impact of the infection environment on phage resistance evolution.
2023
Tatiana Dimitriu – Post-doctoral Fellow
Tatiana is interested in bacterial evolution, particularly coevolution with mobile genetic elements. Her PhD focused on understanding horizontal gene transfer from a social evolution perspective, using modelling and experiments using synthetic bacterial strains. She then used experimental evolution to improve the efficacy of Bacillus thuringiensis, a biocontrol species which virulence is mostly based on social behaviours. She is now investigating how antibiotics can affect bacterial coevolution with phages, and restriction-modification defences.
Alice Maestri – PhD Researcher
Alice is interested in the arms race between bacteria and their parasites, with a specific focus on the evolution and ecology of bacterial immune systems and phage counter-defences. During her PhD she discovered and characterised the MADS immune system and investigated its interaction with the Type IE CRISPR-Cas of Pseudomonas aeruginosa. Previously, her Master research project encompassed phage isolation and characterization for therapy purposes against Vibrio cholerae, under the supervison of Paul Turner and Jean-Paul Pirnay.
2022
Sean Meaden – Post-doctoral Researcher
Sean’s research aimed to understand the ecological and evolutionary drivers of CRISPR immunity in bacterial populations. He used a combination of experimental evolution and population genomics to understand the costs and benefits of CRISPR. Previous research included genomics of an insect-virus system and his PhD focused both on the role of phages in the evolution of a plant pathogen and microbiome shifts during tree disease. Sean is currently a Marie Skłodowska-Curie Actions (MSCA) Research Fellow on secondment at the University of Otago with Peter Finerran’s lab focusing on the abortive infection mechanisms. Twitter: @SeanMeaden
Matthew Chisnall Post-doctoral Fellow
Mathhew’s work was focused on understanding how prokaryotic argonaute proteins contribute to the fitness of bacteria.
Ellie Pursey – PhD Researcher
Ellie’s project focused on the removal of antimicrobial resistance genes from bacterial communities found in the human gut, using CRISPR-Cas9 gene editing. For this, she focused on clinically relevant vancomycin-resistant enterococci, as well as multidrug resistant Enterobacteriaceae. Ellie was primarily supervised by Stineke van Houte in the van Houte lab group, and co-supervised by Edze Westra and Will Gaze (University of Exeter Medical School). Twitter: @ElliePursey
Devi Whittle – Technician/Administrative Support
Devi worked part-time for Prof. Edze Westra’s research group. She assisted in lab management and administrative duties. Devi has a PhD in evolutionary biology and previously worked on a project studying human cultural evolution. She also works with Innovation, Impact and Business supporting innovative research and business development in the agri-food sector. Devi has a background in adult general nursing. Her role with this group was funded by the European Research Council (ERC). Twitter: @ExeterMicrobes
2021
John Bruce – Post-doctoral Fellow
John’s research interest is in the evolution and ecology of social behaviours. His PhD research focused on intraspecific cooperative and competitive interactions in natural bacterial populations. As part of the Westra group, he was investigating the costs and benefits to bacteriophage of using a small-peptide communication system (Arbitrium) to coordinate life history decisions.
Ellinor Opsal Alseth – PhD Researcher
Ellinor was a PhD student working under the supervision of Dr Edze Westra and Prof Angus Buckling. Her PhD thesis focused on the evolution and consequences of bacterial resistance mechanisms against bacteriophages, specifically during human lung infection. Following the successful completion of her PhD (October 2021), Ellinor has secured a prestigious CMDI Early Career Award fellowship to join the Center for Microbial Dynamics and Infection (CMDI) at Georgia Tech, Atlanta, US.
Jack Common – PhD Researcher
With CRISPR-Cas as a model system, his work focused on testing and extending long-standing hypotheses in disease ecology. Jack was particularly interested in how ecological and evolutionary variables, such as density and diversity, can influence host-pathogen dynamics. He was funded by BBSRC SWBio DTP.
2020
Anne Chevallereau – Post-doctoral Fellow
During her PhD (Institut Pasteur, France), Anne investigated how bacteriophages take over their host cell and turn it into viral factories by studying the molecular mechanisms underlying their infectious cycle. She then joined Professor Edze Westra’s research group to explore a different aspect of phage-host interactions. Her research project focused on small proteins encoded on phage genomes that inhibit CRISPR-Cas immune systems. She aimed to understand how the presence of these anti-CRISPR proteins influence the dynamics of phage/bacteria populations. Following her time with the Westra lab, Anne gained a position as a CNRS Researcher at the Cochin Institute, Paris.
Clare Rollie – Post-doctoral Fellow
Claire’s PhD (Biochemistry, University of St Andrews) focussed on understanding how the CRISPR-Cas immune system is updated to target newly encountered foreign genetic elements. In the Westra group, she investigated the importance of the type I-F CRISPR-Cas system of Pseudomonas aeruginosain protection against temperate phage and the fitness consequences of this immunity for the host and the phage parasite. Claire gained a lecturer position at Glasgow University.
Jenny Broniewski – PhD Researcher
Jenny has a background in evolutionary biology. Her work in the Westra lab focused on understanding how and why CRISPR-Cas evolves and what factors make CRISPR-Cas a more or less efficient immune defence. She also investigated the importance of cell-to-cell communication in the evolution of CRISPR and how genetic diversity plays a role in the interaction between bacteria and phage. Following successful completion of her PhD, Jenny gained a position as a Data Officer with the NHS in Truro, Cornwall.
2018
Mariann Landsberger – Postdoctoral Researcher
Mariann is an immunologist with a keen interest in virus-host interactions. During her time in the Westra lab, she focused on different aspects of bacteriophages carrying anti-CRISPR genes, which facilitate the infection of bacteria using the CRISPR-Cas system to depend against phages. Previously she investigated the function of novel orthopoxviral immunomodulators during infection of mammalian cells at Trinity College Dublin.
Dan Morley – MbyRes Student
Dan’s research focuses on the coevolutionary dynamics between bacteria with CRISPR-Cas immunity and their lytic phages. Using Streptococcus thermophilusand phage 2972 as a model system, he investigated whether the hypothesised arms race caused by CRISPR spacer acquisition and phage protospacer mutation can lead to coevolution between both species. He was supervised by Stineke van Houte, Edze Westra and Angus Buckling.
David Sünderhauf – MbyRes Student
Please visit David’s current full profile at the van Houte lab. As part of the Westra lab from 2016-2017, David worked on the interplay of Restriction-Modification and CRISPR-Cas under the supervision of Dr Edze Westra. He is looking to continue research work with Professors Will Gaze and Stineke van Houte on the Joint Programme Initiative (JPI) on Antimicrobial Resistance. Twitter: @davvi36
Olivier Fradet – Technician
Olivier was a post-doctoral fellow in designing and performing large-scale evolution experiments, molecular analyses and in daily lab work. He has an Engineering and Project Management background and previously worked in civil engineering and medico-social fields.
Environment and Sustainability Institute, Penryn Campus, University of Exeter, Penryn TR10 9FE, UK
Contacts:
Edze Westra, Principal Investigator: E.R.Westra@exeter.ac.uk
