Andrew Farr

Evolutionary processes can provide organisms with striking innovative solutions to near-endless environmental challenges. I find these innovations fascinating and our ability to identify and understand their molecular basis deeply rewarding. I performed my PhD studies at Massey University in New Zealand, studying the molecular basis of adaptation in experimental populations of Pseudomonas fluorescens. Along the way I characterized the experimental occurrence of a gene-fusion event, identified a putative contingency locus and explored how genetic architecture biases the production of adaptive mutants. I then studied for 2.5 years in the lab of Arjan de Visser at Wageningen University, working within a HFSP-funded consortium. I developed a strong interest in the adaptive response of bacteria to a challenge by antibiotics. Using flow cytometry and amplicon sequencing, we measured the consequence of cross-protection (the protection of sensitive strains by antibiotic-resistant strains) on the growth advantage of antibiotic resistant beta-lactamase mutants. I’m now unifying my interests in the evolution of antibiotic resistance with the molecular basis of adaptive evolution. We are developing an ambitious experimental design where we try to measure the impact of horizontal gene transfer on the adaptation of Pseudomonas – grown in a complex community of organisms – to environments containing antibiotics.