Coupling between switching regulation and torque generation in bacterial flagellar motor.

ABSTRACT: The bacterial flagellar motor plays a crucial role in both bacterial locomotion and chemotaxis. Recent experiments reveal that the switching dynamics of the motor depend on the rotation speed of the motor, and thus the motor torque, nonmonotonically. Here we present a unified mathematical model which treats motor torque generation based on experimental torque-speed curves and the torque-dependent switching based on the conformational spread model. The model successfully reproduces the observed switching rate as a function of the rotation speed, and provides a generic physical explanation independent of most details. A stator affects the switching dynamics through two mechanisms: accelerating the conformational flipping rate of individual rotor-switching units, which contributes most when t

SUBMITTER: Bai F 

PROVIDER: S-EPMC3558881 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature