Structural insights into flagellar stator-rotor interactions

The bacterial flagellar motor is a molecular machine that can rotate the flagellar filament at high speed. The rotation is generated by the stator-rotor interaction, coupled with an ion flux through the torque-generating stator. Here we employed cryo-electron tomography to visualize the intact flagellar motor in the Lyme disease spirochete,Borrelia burgdorferi. By analyzing the motor structures of wild-type and stator-deletion mutants, we not only localized the stator complexin situ, but also revealed the stator-rotor interaction at an unprecedented detail. Importantly, the stator-rotor interaction induces a conformational change in the flagella C-ring. Given our observation that a non-motile mutant, in which proton flux is blocked, cannot generate the similar conformational change, we propose that the proton-driven torque is responsible for the conformational change required for flagellar rotation.
Source: eLife - Category: Biomedical Science Tags: Microbiology and Infectious Disease Structural Biology and Molecular Biophysics Source Type: research