In vivo evolution of Ctx resistance

Description Bacteria may rapidly develop resistance to antibiotics. We have studied this process in vitro, thereby focusing on the enzyme TEM β-lactamase, which is often involved. We would also like to study this process in vivo by serially transferring populations of bacteria to medium with a steadily increasing amount of antibiotics. After multiple transfers, bacteria with increased Ctx resistance occur. Increased resistance may result from mutations in TEM, but other genes may also play a role. We would like to know the contribution of (1) TEM relative to the other genes and (2) determine the effects of population size on predictability and speed of adaptation.

Used skills: Basic molecular techniques, including PCR, cloning into expression vectors, transformation to bacterial hosts, restriction and sequence analysis; MIC assays; simple bioinformatics and statistical analysis to interpret evolved enzymes.

Requirements: Molecular and Evolutionary Ecology (GEN20304) and Genetic Analyses Tools and Concepts (GEN30306) are a good preparation.

Reference: Buckling A et al. (2009) The Beagle in a bottle. Nature 457: 824-829.