Lucas Le Nagard
15 March 2023
11:00, PJ
I will present the results of a recent study of motile Escherichia coli bacteria encapsulated in lipid vesicles. For slightly deflated vesicles, swimming bacteria deform the vesicles and extrude membrane tubes reminiscent of those seen in eukaryotic cells infected by Listeria monocytogenes. These membrane tubes couple with the flagella of the enclosed bacteria to generate a propulsive force, turning the initially passive vesicles into swimmers. A simple theoretical model used to estimate the magnitude of the propulsive force demonstrates the efficiency of this physical coupling. Interestingly, such vesicle propulsion was not seen in recent studies of swimmers encapsulated in vesicles. While pointing to new design principles for conferring motility to artificial cells, our results illustrate how small differences often matter in active matter physics.