# Modeling mechanical interactions in growing populations of rod-shaped bacteria

## TL;DR

This paper introduces an agent-based model that simulates how mechanical interactions influence the growth and behavior of bacterial populations, providing insights into their complex emergent dynamics in confined environments.

## Contribution

The paper presents a novel computational model coupling cell growth dynamics with mechanical interactions, enabling the study of emergent behaviors in bacterial collectives.

## Key findings

- Mechanical interactions significantly influence bacterial growth patterns.
- The model predicts how constraints affect collective dynamics.
- Mechanical feedback alters cell behavior in confined environments.

## Abstract

Advances in synthetic biology allow us to engineer bacterial collectives with pre-specified characteristics. However, the behavior of these collectives is difficult to understand, as cellular growth and division as well as extra-cellular fluid flow lead to complex, changing arrangements of cells within the population. To rationally engineer and control the behavior of cell collectives we need theoretical and computational tools to understand their emergent spatiotemporal dynamics. Here, we present an agent-based model that allows growing cells to detect and respond to mechanical interactions. Crucially, our model couples the dynamics of cell growth to the cell's environment: Mechanical constraints can affect cellular growth rate and a cell may alter its behavior in response to these constraints. This coupling links the mechanical forces that influence cell growth and emergent behaviors in cell assemblies. We illustrate our approach by showing how mechanical interactions can impact the dynamics of bacterial collectives growing in microfluidic traps.