Genetic competence switching in Streptococcus mutans:  Bacterial circuitry for exploiting internal and external heterogeneity

Bacteria probe their environment and exchange information through a chemical signaling mechanism known as quorum sensing.  Quorum sensing systems can be very complicated, involving multiple signals that can be tuned to respond to, or even exploit, physical and chemical heterogeneity in the environment as well as statistical noise and heterogeneity inside the cell.  I will describe how we are using single cell imaging and microfluidics methods to unravel a stochastically driven, bistable signaling system in Streptococcus mutans, a common human pathogen.