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Measurement of the Internal Frictional Drag of the Bacterial Flagellar Motor by Fluctuation Analysis.

ABSTRACT: The bacterial flagellar motor generates the torque that drives the rotation of bacterial flagellar filaments. The torque it generates depends sensitively on the frictional viscous drag on the motor, which includes the frictional viscous drag on the filaments (external load) and the internal frictional viscous drag on the rotor (internal load). The internal load was roughly estimated previously by modeling it as a sphere of a radius of 20 nm rotating in a lipid of viscosity of 100 cp but was never measured experimentally. Here, we measured the internal load by fluctuation analysis of the motor velocity traces. A similar approach should be applicable to other molecular motors.

SUBMITTER: Wang R

PROVIDER: S-EPMC7264847 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Measurement of the Internal Frictional Drag of the Bacterial Flagellar Motor by Fluctuation Analysis.

Wang Renjie R Chen Qiaopeng Q Zhang Rongjing R Yuan Junhua J

Biophysical journal 20200429 11

The bacterial flagellar motor generates the torque that drives the rotation of bacterial flagellar filaments. The torque it generates depends sensitively on the frictional viscous drag on the motor, which includes the frictional viscous drag on the filaments (external load) and the internal frictional viscous drag on the rotor (internal load). The internal load was roughly estimated previously by modeling it as a sphere of a radius of 20 nm rotating in a lipid of viscosity of 100 cp but was neve ...[more]

PMID: 32392462

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