Stress and Alignment Response to Curved Obstacles in Growing Bacterial Monolayers
arXiv:2401.17222 · doi:10.1103/PhysRevE.109.054608
Abstract
Monolayers of growing bacteria, confined within channel geometries, exhibit self-organization into a highly aligned laminar state along the axis of the channel. Although this phenomenon has been observed in experiments and simulations under various boundary conditions, the underlying physical mechanism driving this alignment remains unclear. In this study, we conduct simulations of growing bacteria in 2D channel geometries perturbed by fixed obstacles, either circular or arc-shaped, placed at the channel's center. Our findings reveal that even sizable obstacles cause only short-ranged disruptions to the baseline laminar state. These disruptions arise from a competition between local planar anchoring and bulk laminar alignment. At smaller obstacle sizes, bulk alignment fully dominates, while at larger sizes, planar anchoring induces increasing local disruptions. Furthermore, our analysis indicates that the resulting configurations of the bacterial system display a striking resemblance to the arrangement of hard-rod smectic liquid crystals around circular obstacles. This suggests that modeling hard-rod bacterial monolayers as smectic, rather than nematic, liquid crystals may yield successful outcomes. The insights gained from our study contribute to the expanding body of research on bacterial growth in channels. Our work provides new perspectives on the stability of the laminar state and extends our understanding to encompass more intricate confinement schemes.
References in corpus (17)
- Spontaneous motion in hierarchically assembled active matter
- Fluid dynamics of bacterial turbulence
- Topological defect launches 3D mound in the active nematic sheet of neural progenitors
- Defect dynamics in active nematics
- Topological defects promote layer formation in Myxococcus xanthus colonies
- Mechanically driven growth of quasi-two dimensional microbial colonies
- Nonequilibrium steady states in a vibrated-rod monolayer: tetratic, nematic and smectic correlations
- Cell division: a source of active stress in cellular monolayers
- Emergence of active nematics in bacterial biofilms
- Optimal Control of Active Nematics
- Submersed Micropatterned Structures Control Active Nematic Flow, Topology and Concentration
- Confinement-induced self-organization in growing bacterial colonies
- Particle-resolved topological defects of smectic colloidal liquid crystals in extreme confinement
- Large-scale orientational order in bacterial colonies during inward growth
- Microdomains and Stress Distributions in Bacterial Monolayers on Curved Interfaces
- Tubulation and dispersion of oil by bacterial growth on droplets
- Colloidal smectics in button-like confinements: experiment and theory