With this award, the NSF Chemistry of Life Processes program is supporting the research of Professor Helen E. Blackwell at the University of Wisconsin-Madison. Professor Blackwell seeks to interrogate the mechanisms by which eukaryotes intercept bacterial communication pathways at the host-bacteria interface. Bacteria use a chemical language of small molecules to assess local population densities in a process known as "quorum sensing" (QS). Plant-associated bacteria use QS to regulate critical processes both harmful and beneficial to their plant host. It is now evident that many plant hosts, in turn, "listen" to these bacterial signals and can respond with their own chemical signals that influence bacterial pathogenesis and symbiosis. The reliance of both bacteria and plants on a language of small molecules places organic chemists in a unique position to uncover the fundamental principles underlying this communication network and design new tools to modulate it at the molecular level. Blackwell and her team propose to (1) identify non-native small molecules capable of intercepting bacterial QS at the plant-bacteria interface, (2) delineate the mechanisms by which plants sense and respond to native and non-native QS signals, and (3) characterize the native small molecule signals used by plants to intercept bacterial QS.
The Broader Impacts of this research project are potentially wide-ranging. Prof. Blackwell's discoveries should be applicable to host organisms beyond plants, and will likely shed light upon the mechanisms by which QS occurs in host eukaryotes, in general. As such, the CLP program sees this project as having elements of high risk/high reward in interrogating front-line questions in the growing fields of QS and sociomicrobiology. Students involved in this project will be exposed to multidisciplinary research involving organic synthesis, bacteriology, protein biochemistry, molecular biology, plant science and bio-analytical chemistry. This is expected to provide an excellent training environment at the chemistry-biology interface.