Use this URL to cite or link to this record in EThOS:
Title: Electrorotation of the bacterial flagellar motor
Author: Saxl, Tania E.
ISNI:       0000 0001 3554 4591
Awarding Body: University of Oxford
Current Institution: University of Oxford
Date of Award: 2007
Availability of Full Text:
Full text unavailable from EThOS.
Please contact the current institution’s library for further details.
Knowledge of the relationship between the torque generated by the bacterial flagellar motor of Escherichia coli and its rotation rate provides a valuable insight into the mechanism of the motor's function. A method was devised to measure this characteristic in the high-speed, low-load regime, so that the effect of stator number could be investigated. This i~volved the electrorotation of a polarisable particle, attached to the bacterial filament, as a handle to rotate the motor. I designed and built an upright laser position detector and fabricated an electrode flow cell and optically asymmetric, polarisable particles. The particles allow a high resolution to be achieved, so that stator numbers can be distinguished. The flow cell enables positioning of the bacterium with respect to the electrodes and exchange of the medium during the experiment. Using the novel flow cell, previous torque speed measurements for the flagellar motor of E. coli, made by rotating the cell body about its tether point, were confirmed. The method was extended to measure the torque speed curve for the polarisable particle attached to the filament. I was then able to determine a torque speed curve for varying stator numbers. Results indicate that the zero-torque speed decreases for decreasing stator numbers, contrary to previous assumptions.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available