From molecules to behavior in bacterial chemotaxis
Institute for Biophysical Dynamics, University of Chicago
James Franck Institute, University of Chicago
Last modified: June 22, 2006
The chemotaxis system in Escherichia coli, one of the simplest sensory systems in biology, exhibits robust properties at the population level, as well as high behavioral variability at the single cell level. The fluctuation-dissipation theorem provides a standard framework to clarify the relationship between molecular noise within signal transduction networks and the timing of the cellular response to small stimuli. Using this approach we built a stochastic model of the bacterial chemotaxis signaling pathway. Our model predicts a relationship between the time scale of adaptation and the behavioral variability of a single bacterium. We illustrate our predictions using the agent-based simulator AgentCell to model the behavior of more than 1000 independent digital bacteria, where each bacterium had its own chemotaxis locomotion system.