Micro-organisms biophysics

We investigate bacteria from single cell to population level. We take advantage of their appropriate reproduction time scale to address fundamental and general questions such as mutation processes, community expansion physical mechanisms and causal relationships linking physico-chemical parameters of the environment and biological responses. To this end, we design and implement microfluidic devices aimed at real time monitoring of living bacterial models such as Escherichia coliPseudomonas aeruginosaBacillus subtilis using video microscopy and image analysis. Our approach relies on implementing concepts from mathematics, physics and physico-chemistry to achieve quantitative analyses of the targeted processes.

Our activities cover different projects:

Future directions

  • Local imaging of oxygen in bacterial biofilms based on FLIM monitoring of fluorescent tracers and laser sheet illumination.
  • Characterization of internal structure of swarming colonies by contrast imaging.
  • Effect of age, stress and infection on the mutation dynamics in E. coli mutations at the single cell level in controlled conditions and on large timescales.
  • Distribution of fitness effects of mutations (DFE) changes with the environmental conditions. "Microfluidic Mutation Accumulation" experiments (?MA) in the "mother machine" microfluidic chip, and accumulation of mutations in the complete absence of natural selection.