Bacterial chemotaxis in confining geometries
Elliot Marsden, University of Edinburgh
Many bacteria have evolved the ability to move actively through their environment, and also to direct this motion towards beneficial substances or away from harmful ones -- chemotaxis. It has been suggested that in stressful conditions such chemicals may be secreted by bacteria themselves, introducing the potential for chemotaxis to be used for inter-bacterial signalling and collective motion. It has also been shown that non-uniform distributions of bacteria can be produced through control of the environmental topology. Here I will address the behaviour arising from the interplay of these two phenomena. I will introduce a theoretical model of chemotaxis, and show results of simulations with the aim of reproducing experiments. These suggest that the interaction of bacteria with planar surfaces, coupled with chemotaxis towards a self-secreted chemoattractant, may explain spontaneous clustering in chemically uniform environments. This has implications for control of bacterial populations via shaping of the environment, and may provide insight into how bacteria can achieve a critical density for virulence through chemical signalling.