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\textbf{\LARGE A\Large BSTRACT}
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\large \sc Control of the Unidirectional Motor in \\
\large \sc \emph{Rhodobacter sphaeroides} \\
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{\sc Mostyn T. Brown}\\
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{\small Thesis submitted for the degree of Doctor of Philosophy, \\ 
University of Oxford, Trinity Term 2009\\}
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Complementation studies revealed that \yiii{}, \yiv{}, and \yv{} are functionally equivalent. The copy numbers per cell of important CheYs were found to vary greatly under the conditions tested ($<$1,000, $\sim$3,000, $\sim$60,000 for \yiii{}, \yiv{}, and \yvi{} respectively).
