Characterization and Control of the Run-and-Tumble Dynamics of {\it Escherichia Coli}

TL;DR

This paper quantitatively characterizes the swimming behavior of E. coli, demonstrating control over motility patterns and linking microscopic motility parameters to large-scale diffusion using renewal process analysis.

Contribution

It introduces a method to analyze E. coli motility using renewal processes and reports controlled transitions in swimming behavior, bridging microscopic and macroscopic dynamics.

Findings

Controlled transition from tumbling to smooth swimming.

Quantitative link between microscopic motility and diffusion.

Method for analyzing bacterial motility using renewal processes.

Abstract

We characterize the full spatiotemporal gait of populations of swimming {\it Escherichia coli} using renewal processes to analyze the measurements of intermediate scattering functions. This allows us to demonstrate quantitatively how the persistence length of an engineered strain can be controlled by a chemical inducer and to report a controlled transition from perpetual tumbling to smooth swimming. For wild-type {\it E.~coli}, we measure simultaneously the microscopic motility parameters and the large-scale effective diffusivity, hence quantitatively bridging for the first time small-scale directed swimming and macroscopic diffusion.