糖心TV

Abstract: Laboratory based evolution (LBE) can be used to study evolution as a process per se, and also as a tool to provide insights (hopefully novel ones) into any organism that has the requisite characteristics of rapid growth and division under simple experimental conditions. By coupling evolution experiments with whole genome sequencing, it is fairly straightforward to identify the genetic outcome of any LBE experiment. Explaining the selected phenotype in terms of the new genotype may be more challenging. We are interested in the short and long term responses of E. coli to stresses that it may encounter during its passage through the human gut, and in this context I will describe two LBE experiments, one selecting for survival at very low pH, and one selecting for growth at moderately low pH. I'll describe how quite different consequences arise from these two experiments, and show the extent to which we can link genotype to phenotype in both cases. I'll show how we have also learned something along the way about the reproducibility of evolutionary trajectories, about the sorts of mutations that provide a selective advantage in these types of experiments, and about E. coli stress responses in general.

Biography: Peter is Reader in Molecular Microbiology and a member of the Institute of Microbiology and Infection at the University of Birmingham, where he has worked for far too long. His research focus is on microbial stress responses, with particular interests in two areas: molecular chaperone biology, and microbial responses to low pH. Current research projects include the use of high throughput methods (RNAseq, traDIS) and lab-based evolution to study stress responses, the potential of organic acids for treatment of wound infections, and understanding the roles of chaperonins in Mycobacterial infections. He also has a long-standing interest in science and ethics and has served on three of the committees that regulate GM in the UK: ACNFP, ACRE, and SACGM; this gives him an unparalleled insight into government acronyms in this area.