How can bacteria find their way towards a source of sugar? This was the topic of the lecture 'Design Principals of a Bacterial Signalling Network' of Professor Jens Timmer of the University of Freiburg in Germany. He spoke at CWI during the first seminar in the Seminar Series Systems Biology of the Bio Centrum Amsterdam, on Monday 8 May 2006.
E. coli bacteria have sensors at their fronts and propeller tails at their backs like outboard motors. How do they know in which direction they should move when they are swimming where sugar concentrations vary widely due to local currents? Timmer studied chains of biochemical reactions - biochemical networks - in these bacteria to learn how a signal from the front sensors is being transferred to the motors in the tails.
Timmer used mathematical models in the form of differential equations. The criterion which a realistic model has to satisfy is that it allows determination of the increase or decrease of the sugar concentration for a very wide range of such concentrations. Of the four proposed models only one model met this criterion.
Timmer is a well-known theoretical physicist and one of the pioneers of German systems biology. The audience of the lecture consisted of more than 50 scientists. The Bio Centrum Amsterdam is a research school of the University of Amsterdam and of the Vrije Universiteit with which AMOLF and CWI are affiliated.
