In many natural environments, bacteria collectively aggregate to exist in densely populated and structurally diverse communities called biofilms. In our lab, we work with Bacillus subtilis as a model system to study biofilm formation. Within these biofilm communities, B. Subtilis cells can exhibit a multiplicity of phenotypic cell types, with diverse subpopulations that are involved in motility, spore formation and matrix production. Consequently, biofilms exhibit properties that far exceed their capabilities as individual bacteria. For example, microbial biofilms are roughly 10,000x more antibiotic resistant that individual cells. Despite being found nearly everywhere - from lakes to hot springs to our own teeth – biofilms still present several unanswered questions.
A key feature of biofilms is the ability of the constituent bacteria, which are genetically identical, to exhibit a range of phenotypes according to a variety of cues. The spatiotemporal variations in the expression of these different phenotypes (swimming, matrix production, and sporulation) and how the biofilm regulates these behaviors across millions of individual members is the focus of our research. In other words: 1) How does a bacteria decide what it should do with its life, 2) how does it know how old it is andwhere it is, and 3) how does it decide who are its friends and who are its enemies. The results of this work could provide insight into how to control biofilm formation and provide new ways to tackle the deadly diseases associated with biofilm infections or alternatively provide ways to harness bacteria to produce clean energy.
Time-lapse progression of an edge of a biofilm.