Confinement-induced self-organization in growing bacterial colonies

Science Advances, vol. 7

Abstract

We investigate the emergence of global alignment in colonies of dividing rod-shaped cells under confinement. Using molecular dynamics simulations and continuous modeling, we demonstrate that geometrical anisotropies in the confining environment give rise to an imbalance in the normal stresses, which, in turn, drives a collective rearrangement of the cells. This behavior crucially relies on the colony's solid-like mechanical response at short time scales and can be recovered within the framework of active hydrodynamics upon modeling bacterial colonies as growing viscoelastic gels characterized by Maxwell-like stress relaxation.

Authors 2

1. Zhihong You Aachen Instituut-Lorentz

   Leiden University · University of California, Santa Barbara

   Affiliation as printed

   Department of Physics, University of California, Santa Barbara, Santa Barbara, CA 93106, USA

   Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, Netherlands

2. Luca Giomi corresponding Aachen Instituut-Lorentz

   Leiden University

   Affiliation as printed

   Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, Netherlands