The ability of bacteria to communicate using diffusible chemical signals is required for a variety of functions, including virulence and biofilm formation. Our lab is studying cell-to-cell signaling in the human pathogen Acinetobacter baumannii with the goal of understanding the role of this process in virulence. These studies involve: (i) purification and structural characterization of extracellular signaling molecules, (ii) identification of genes involved in signal response, (iii) identification of genes involved in signal production, and (iv) the use of RNA-Seq to identify genes activated/repressed by extracellular signals.
A second area of study addresses the mechanisms that allow the urinary tract pathogen Proteus mirabilis to differentiate to swarmer cells. The role of a regulatory molecule, phenethylamine, in controlling the activity of a key transcriptional regulator (FlhDC) is being investigated. In addition, we are investigating the mechanisms that allow P. mirabilis to sense surfaces and transmit these signals to the regulation of gene expression.