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DY: Dynamik und Statistische Physik
DY 41: Dynamical Physics in Biological Systems
DY 41.5: Vortrag
Donnerstag, 30. März 2006, 11:00–11:15, SCH 251
Discrete Model for Pattern Formation in Bacterial Colonies — •Pawel Romanczuk1, Udo Erdmann2, Harald Engel1, and Lutz Schimansky-Geier2 — 1Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin, Germany — 2Institute für Physik, Humboldt Universität zu Berlin, Newtonstr. 15, 12489 Berlin, Germany
Bacterial colonies of Escherichia coli and Salmonella typhimurium show complex patterns of high density cell aggregates when exposed to certain nutrients. Decisive for this pattern formation is the production of a potent chemoattractor by the bacteria as a reaction to the nutrient [1]. The observed bacterial patterns range from temporary spots formed in liquid medium to “sunflower like” spot arrangements of striking complexity in a semi-solid medium. Motivated by this observations we suggest a simple model for the description of bacterial colonies based on the concept of Active Brownian motion [2]. Our model represents an interesting alternative to the usually employed “pure” reaction-diffusion equations as it allows us to study the macroscopic pattern formation of the colony, the mesoscopic dynamics of bacterial ensembles (swarming), as well as the microscopic dynamics of single cells. Here we will present the obtained qualitative and quantitative numerical results of our model and compare them with the experimentally observed bacterial dynamics.
[1] Budrene, E. O. und H. C. Berg: Dynamics of formation of symmetrical patterns by chemotactic bacteria. Nature, 376:49-53, 1995.
[2] Erdmann, U.,Kollektive Bewegung, Logos Verlag, Berlin, 2004.