Bacterial colonization in realistic environments: how mechanics impact biofilm formation in the wild and during infection

A variety of physical inputs acts onto bacteria in nature. However, these are most often ignored in the studies of their physiology. There is now increasing evidence indicating that bacteria respond to physical stimuli, including mechanical forces. Yet, quantitative links between environmental mechanics, bacterial colonization and physiology remains to be established. For that purpose, studying bacteria in environments integrating relevant mechanical features is necessary. The constant improvement of microfabrication technologies and tissue engineering provides us with valuable tools to mimic such environments in the laboratory. In my PhD project, I will seek to engineer such environment with the goal to understand how mechanics influence bacteria in two distinct settings: 1) I will investigate how flow intensity modulates biofilm formation and architecture of the freshwater bacterium Caulobacter crescentus. To characterize this, I will use a microfluidics approach; 2) I will characterize how mucosal mechanics influence colonization of the respiratory tract by the pathogen Pseudomonas aeruginosa. I will achieve this using a tissue engineering approach. Overall, the goal of my PhD is to develop new platforms to study microbes in a more realistic physical context, and to gain knowledge on the complex interplay between physics and microbiology that determines the fate of bacteria in natural environments.