A new way for quantifying bacterial chemotaxis with the three channels microfluidic chip*

Chemotaxis is the ability for a bacteria to bias its swimming activity in chemical gradients and to move towards favorable environments. This is an example of a phenomenon that is essential during the pre-infection phase of roots by symbiotic soil bacteria.

In this study, we use microfluidic chip to generate a steady, shear-free chemical gradient and to track bacteria trajectories. We aim to understand the role of surfaces in the migration of bacteria towards the favorable environment.

My study shows the role of swimming pattern on chemotactic response. To do this, I used various strains of bacteria (Escherichia coli,Sinorhizobia meliloti, Burkholderia contaminans, and Caballeronia insecticola) which exhibit "run and tumble",  “run-desynchronize” or "run-reverse" swimming patterns.