We are principally interested in two topics: 1) the features and mechanisms of bacterial stress responses, using Bacillus subtilis as a model species, and 2) the metabolism and behavior of the opportunistic human pathogen Pseudomonas aeruginosa, with a special focus on its ability to produce pyocins, phage tail-like intraspecific killing complexes.
Our research uses many different techniques, from bacterial molecular genetics and traditional culture techniques to modern "omics" approaches and advanced microscopy. We benefit particularly from microfluidic technology, which permits us to observe cells under a light microscope as they grow and has several advantages over traditional analytical methods. For example, because the cells are constantly bathed in fresh growth medium, we can follow cells for tens or hundreds of generations in constant and uniform growth conditions. We can manipulate the composition of the growth medium, adding or removing stressors or other compounds, so that we can observe the immediate and long-term responses of cells to the compounds that we add. Because the growth conditions are uniform, we can examine the true responses of cells apart from self-induced changes to the local environment caused by nutrient depletion or waste produce buildup. Finally, because we observe cells under the microscope, we achieve single-cell resolution, allowing us to assess cell-to-cell variability across a population of cells. We typically use fluorescent reporters to observe the inner workings of cells as they grow and respond to changes in their environment.