Bacterial Communication and Cooperation: From Understanding to Applications

Abstract

Bacteria communicate, coordinate, and cooperate as a population and this `social' behavior is key to their proliferation. Quorum sensing (QS) is the cell-cell communication mechanism by which bacteria sense their population density and modulate their target gene expression accordingly. While QS is ubiquitous among bacteria, there is tremendous diversity in terms of the sensory elements used and the biochemical and transport properties of signaling molecules. Further, the targets of QS include a wide range of cooperative actions, such as the secretion of enzymes for nutrient foraging, virulence toxins, and biofilm-forming compounds. Here I investigate what role QS and cooperation play, as universal social characteristics, in promoting bacterial proliferation.Engineered biological circuits offer the potential to test our understanding of natural systems under well-defined contexts, by focusing on the key characteristics and components of interest. In my doctoral work, I have taken advantage of this methodology to study bacterial social behavior. Combining mathematical modeling with quantitative experiments using gene circuits, my research has (1) elucidated the `core' components of cell-cell communication across bacteria, (2) explained how communication and cooperation advantage bacterial growth, and (3) opened up the important application of this research in generating novel antibacterial therapies.