Controlling confined collective organisation with taxis

Thery, A.; Chamolly, A.; Lauga, E.

doi:10.1101/2023.12.05.570159

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bioRxiv · 10.1101/2023.12.05.570159

Controlling confined collective organisation with taxis

Thery, A.·Chamolly, A.·Lauga, E.

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Abstract

Biased locomotion is a common feature of microorganisms, but little is known about its impact on self-organisation. Inspired by recent experiments showing a transition to large-scale flows, we study theoretically the dynamics of magnetotactic bacteria confined to a drop. We reveal two symmetry-breaking mechanisms (one local chiral and one global achiral) leading to self-organisation into global vortices and a net torque exerted on the drop. The collective behaviour is ultimately controlled by the swimmers microscopic chirality and, strikingly, the system can exhibit oscillations and memory-like features.

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Thery, A., Chamolly, A., Lauga, E.. 2023-12-07. Controlling confined collective organisation with taxis. https://doi.org/10.1101/2023.12.05.570159

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