Anisotropic random walks reveal chemotaxis signaling output in run-reversing bacteria
Institutional Repository Document
Overview
Research
Identity
Other
View All
Overview
abstract
AbstractThe bias for a particular direction of rotation of the flagellar motor is a sensitive readout of chemotaxis signaling, which mediates bacterial migration towards favorable chemical environments. The rotational bias has not been characterized inHelicobacter pylori, which limits our understanding of the signaling dynamics. Here, we determined thatH. pyloriswim faster (slower) whenever their flagella rotate counterclockwise (clockwise) by analyzing their hydrodynamic interactions with bounding surfaces. The anisotropy in swimming speeds helped quantify the fraction of the time that the cells swam slower to report the first measurements of the bias. A stochastic model of run-reversals indicated that the anisotropy promotes faster spread compared to isotropic swimmers. The approach further revealed that the diffuse spread ofH. pyloriis likely limited at the physiological temperature due to increased reversal frequencies. Thus, anisotropic run-reversals make it feasible to study signal-response relations in the chemotaxis network in non-model bacterial species.Impact StatementAnisotropy in run and reversal swimming speeds promotes the spread ofH. pyloriand reveals temperature-dependent behavior of the flagellar switch.
