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Self Trapping of a Single Bacterium in its Own Chemoattractant

Yoav Tsori·Pierre-Gilles de Gennes
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Abstract

Bacteria (e.g. E. Coli) are very sensitive to certain chemoattractants (e.g. asparate) which they themselves produce. This leads to chemical instabilities in a uniform population. We discuss here the different case of a single bacterium, following the general scheme of Brenner, Levitov and Budrene. We show that in one and two dimensions (in a capillary or in a thin film) the bacterium can become self-trapped in its cloud of attractant. This should occur if a certain coupling constant $g$ is larger than unity. We then estimate the reduced diffusion D_eff of the bacterium in the strong coupling limit, and find D_eff ~ 1/g.

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Yoav Tsori, Pierre-Gilles de Gennes. 2004-05-05. Self Trapping of a Single Bacterium in its Own Chemoattractant. https://doi.org/10.1209/epl%2Fi2003-10237-5

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