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Title: Stochastic motion of microorganisms
Author: King, A. J.
Awarding Body: University College of Swansea
Current Institution: Swansea University
Date of Award: 1980
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Studies of bacterial motion and the apparatus used in such studies are reviewed. The problems of two and three dimensional tracking systems are considered. A system for tracking bacteria has been constructed using a dark field illumination microscope with a modified optical system. The main features of this system are: a) The depth of field is 0.1 millimetre. b) The field of view is nearly 2 millimetres. c) The contrast of bacteria to their surroundings is made an optimum by using small angle scattering techniques. These features enable the two dimensional motions of bacteria to be recorded on video tape for times greater than five minutes. Smooth and jagged bacterial tracks have been recorded and digitised to within a position accuracy of one micron. The tracks are analysed by a computer. It is shown that with slight modifications to the system three dimensional tracking can be accomplished. The results obtained suggest that for the strain of Escherichia coli tracked: 1) Each bacterium swam at a preferred speed and in a smooth trajectory, except for an occasional and sudden change in direction. 2) The bacteria swim in circles close to a glass surface. Future work on the tracking system and on bacterial motion is suggested.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available