Torque, but not FliL, regulates mechanosensitive flagellar motor-function

Abstract The stator-complex in the bacterial flagellar motor is responsible for surface-sensing. It remodels in response to perturbations in viscous loads, recruiting additional stator-units as the load increases. Here, we tested a hypothesis that the amount of torque generated by each stator-unit m...

Description complète

Enregistré dans:
Détails bibliographiques
Auteurs principaux: Ravi Chawla, Katie M. Ford, Pushkar P. Lele
Format: article
Langue:EN
Publié: Nature Portfolio 2017
Sujets:
R
Q
Accès en ligne:https://doaj.org/article/d5b89c12869d4a4882eb491dd6fe1569
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
id oai:doaj.org-article:d5b89c12869d4a4882eb491dd6fe1569
record_format dspace
spelling oai:doaj.org-article:d5b89c12869d4a4882eb491dd6fe15692021-12-02T15:06:16ZTorque, but not FliL, regulates mechanosensitive flagellar motor-function10.1038/s41598-017-05521-82045-2322https://doaj.org/article/d5b89c12869d4a4882eb491dd6fe15692017-07-01T00:00:00Zhttps://doi.org/10.1038/s41598-017-05521-8https://doaj.org/toc/2045-2322Abstract The stator-complex in the bacterial flagellar motor is responsible for surface-sensing. It remodels in response to perturbations in viscous loads, recruiting additional stator-units as the load increases. Here, we tested a hypothesis that the amount of torque generated by each stator-unit modulates its association with the rotor. To do this, we measured stator-binding to the rotor in mutants in which motors reportedly develop lower torque compared to wildtype motors. First, we employed a strain lacking fliL. Contrary to earlier reports, measurements indicated that the torque generated by motors in the fliL strain was similar to that in the wildtype, at high loads. In these motors, stator-binding was unchanged. Next, experiments with a paralyzed strain indicated that the stator-binding was measurably weaker when motors were unable to generate torque. An analytical model was developed that incorporated an exponential dependence of the unit’s dissociation rate on the force delivered to the rotor. The model provided accurate fits to measurements of stator-rotor binding over a wide range of loads. Based on these results, we propose that the binding of each stator-unit is enhanced by the force it develops. Furthermore, FliL does not play a significant role in motor function in E. coli.Ravi ChawlaKatie M. FordPushkar P. LeleNature PortfolioarticleMedicineRScienceQENScientific Reports, Vol 7, Iss 1, Pp 1-9 (2017)
institution DOAJ
collection DOAJ
language EN
topic Medicine
R
Science
Q
spellingShingle Medicine
R
Science
Q
Ravi Chawla
Katie M. Ford
Pushkar P. Lele
Torque, but not FliL, regulates mechanosensitive flagellar motor-function
description Abstract The stator-complex in the bacterial flagellar motor is responsible for surface-sensing. It remodels in response to perturbations in viscous loads, recruiting additional stator-units as the load increases. Here, we tested a hypothesis that the amount of torque generated by each stator-unit modulates its association with the rotor. To do this, we measured stator-binding to the rotor in mutants in which motors reportedly develop lower torque compared to wildtype motors. First, we employed a strain lacking fliL. Contrary to earlier reports, measurements indicated that the torque generated by motors in the fliL strain was similar to that in the wildtype, at high loads. In these motors, stator-binding was unchanged. Next, experiments with a paralyzed strain indicated that the stator-binding was measurably weaker when motors were unable to generate torque. An analytical model was developed that incorporated an exponential dependence of the unit’s dissociation rate on the force delivered to the rotor. The model provided accurate fits to measurements of stator-rotor binding over a wide range of loads. Based on these results, we propose that the binding of each stator-unit is enhanced by the force it develops. Furthermore, FliL does not play a significant role in motor function in E. coli.
format article
author Ravi Chawla
Katie M. Ford
Pushkar P. Lele
author_facet Ravi Chawla
Katie M. Ford
Pushkar P. Lele
author_sort Ravi Chawla
title Torque, but not FliL, regulates mechanosensitive flagellar motor-function
title_short Torque, but not FliL, regulates mechanosensitive flagellar motor-function
title_full Torque, but not FliL, regulates mechanosensitive flagellar motor-function
title_fullStr Torque, but not FliL, regulates mechanosensitive flagellar motor-function
title_full_unstemmed Torque, but not FliL, regulates mechanosensitive flagellar motor-function
title_sort torque, but not flil, regulates mechanosensitive flagellar motor-function
publisher Nature Portfolio
publishDate 2017
url https://doaj.org/article/d5b89c12869d4a4882eb491dd6fe1569
work_keys_str_mv AT ravichawla torquebutnotflilregulatesmechanosensitiveflagellarmotorfunction
AT katiemford torquebutnotflilregulatesmechanosensitiveflagellarmotorfunction
AT pushkarplele torquebutnotflilregulatesmechanosensitiveflagellarmotorfunction
_version_ 1718388545053261824