Systems Biology of Bacterial Chemotaxis: A Story of Macromolecular Complexes

Robert G. Endres

The chemotaxis network in the bacterium Escherichia coli is the best characterized signal-transduction network of any living organism. The system integrates signals from different chemical cues using membrane- bound chemoreceptors and transduces the signal to molecular motors, allowing taxis toward any of multiple attractants, and away from repellents. The chemotaxis sensory system exhibits remarkable properties, such as high sensitivity over a wide range of chemical concentrations and precise adaptation to constant background concentrations. The chemotaxis system of E. coli is sufficiently complex that understanding its signaling properties requires computational modeling. In this talk, I will provide new understanding of signal integration and precise adaptation by clusters of chemoreceptors. Currently, the model is being extended to address the assembly of clusters in the membrane, as well as the engineering principals of the network.