MacLean Lab

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MacLean Lab

About the Group

Research in the MacLean lab is focused on understanding the evolutionary biology of antibiotic resistance in pathogenic bacteria. Bacteria have evolved a wide diversity of mechanisms for combating antibiotics, and the spread of resistance depends on processes that occur across a broad range of biological scales ranging from individual molecules to bacterial communities. We try and embrace this diversity by working on resistance evolution from a variety of different perspectives, and the main themes of our research are outlined below.  

Fitness costs and compensatory evolution

Antibiotic resistance usually reduces bacterial competitive ability, and this fitness cost is thought to represent a key obstacle to the spread of resistance at an epidemiological scale. We are interested in understanding why resistance carries a cost, and when this cost will cause resistance to decline after antibiotic use is reduced.

Evolutionary consequences of intervention strategies

How should we use antibiotics? This theme explores the evolutionary consequences of different intervention strategies, such as altering the frequency and intensity of antibiotic use, and how this impacts the dynamics of resistance at a population level.

Mobile resistance

Many of the most important antibiotic resistance genes in clinical pathogens are found on plasmids, autonomously replicating circles of DNA that can jump between bacteria. We are interested in understanding why resistance genes are on plasmids, and on how plasmids can persist in bacterial populations when antibiotic use declines.

Genomic drivers of resistance

Bacteria show extensive diversity in genome content and sequence. We are interested in understanding how genomic background shapes the rate and mechanisms of resistance evolution.

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Craig MacLean, Wellcome Trust Senior Research Fellow and Associate Professor

Andrei Papkou, Postdoc
Jessica Hedge, Postdoc
Natalia Kapel, Research Assistant
Helen Alexander, Swiss National Science Foundation Postdoctoral Fellow
Isuru Goonatilake, DPhil Student 
Celia Souque, DPhil Student
Jacqueline Gill, DPhil Student

Recent Publications

A. San Millan, J.A Escudero*, D.Gifford*, D. Mazel and R.C MacLean. Multicopy plasmids potentiate the evolution of antibiotic resistance in bacteria. Nature Ecology and Evolution (2016) DOI:10.1038/s41559-016-0010  [Link] [Nature Microbiology Comment][Faculty of 1000][Behind the paper]

M.Toll-Riera, A. San Millan, A. Wagner and R. C MacLean. The genomic basis of evolutionary innovation in Pseudomonas aeruginosa. PLOS Genetics (2016) doi:10.1371/journal.pgen.1006005 [Link]

A. San Millan, M. Toll-Riera, Q. Qi and R.C. MacLean. Interactions between horizontally acquired genes create a fitness cost in Pseudomonas aeruginosa. Nature Communications (2015) 6, doi:10.1038/ncomms7845 [Link]

A. San Millan*, R.Peña-Miller*, M. Toll-Riera, Z.Halbert, A.McLean, B.Cooper and R.C MacLean. Positive selection and compensatory adaptation interact to stabilize non-transmissible plasmids. Nature Communications (2014) 5, doi:10.1038/ncomms6208. [Link]

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