Charles and William L. Day Distinguished Professor in the Natural Sciences
Department of Biology and Department of Physics & Astronomy
University of Pennsylvania
"Hedging bets in bacterial signal transduction"
E. coli, like most bacteria, sense a wide variety of physical and chemical signals, a feature that enables them to adapt to diverse changes in their environment. The response to specific signals usually elicits a relatively uniform response among cells in a bacterial culture. In some cases, however, the response is very heterogeneous across the population. We have uncovered one example of such a signal transduction system with the unusual twist that an environmental cue—oxygen—regulates the cell-to-cell variability of the system output without affecting the mean. I will describe our work to understand the causes and consequences of this behavior.