Biophysical Society Thematic Meeting | Ascona 2026

Mechanobiology of Infection

Sunday Speaker Abstracts

BACTERIA TUNE COLLECTIVE NAVIGATION BY MECHANOSENSING COLLISIONS Laure Le Blanc 1,2 ; Giona Cattaneo 1,2 ; Nathel Heraud 1,2 ; Einollah Sarikhani 3 ; Dhivya Pushpa Meganathan 3 ; Chia-Ni Tsai 1,2 ; Anum Tahir 3 ; Marco Kühn 1,2 ; Zeinab Jahed 3 ; Sangwoo Kim 4 ; Alexandre Persat 1,2 ; 1 École Polytechnique Fédérale de Lausanne, Global Health Institute, School of Life Sciences, Lausanne, Switzerland 2 École Polytechnique Fédérale de Lausanne, Institute of Bioengineering, School of Life Sciences, Lausanne, Switzerland 3 University of California San Diego, Department of Chemical and Nano Engineering, La Jolla, CA, USA 4 École Polytechnique Fédérale de Lausanne, Institute of Mechanical Engineering, Lausanne, Switzerland Navigating complex environments is a fundamental challenge shared across the tree of life, requiring organisms to balance individual and collective locomotion. Here, we show that the bacterial pathogen Pseudomonas aeruginosa balance individual and group motility using mechanosensation to enhance surface exploration. During twitching motility, P. aeruginosa reverses direction when colliding with neighboring cells, which suppresses the spontaneous group formation characteristic of collective locomotion. Unlike non-reversing mechanosensing mutants that move in cohesive, quasi-ballistic groups, wild-type cells adjust their trajectories with local cell density, transitioning from superdiffusive motion in crowds to quasi-ballistic movement toward new territory. Using microfabricated mazes, we demonstrate that this adaptive behavior enables bacteria to navigate spatially structured environments. We propose that the same principle extends to the colony scale: by continuously reorienting away from the crowd, wild-type cells spread faster than mechanosensing-deficient mutants. Together, these findings establish mechanosensation as a primary driver of the spreading capacity of P. aeruginosa. Given that bacteria must navigate the spatially complex architecture of the lung to establish infection, this mechanosensory strategy may shape early infection dynamics and pathogenesis.

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