Designing Microbes for Executive Function

Signal molecules play an important role in determining biological function. Signaling among bacteria is mediated by small molecules that are produced, secreted, accumulated, perceived and transduced in a variety of manners that span biophysical and genetic regulatory domains. Often the signal molecule’s structure is determinant in defining function. Self-reporting number density is referred to as quorum sensing is such an example; its use enables phenotypic noise reduction for specific cell subpopulations in natural environments.   Sometimes, the signal transduction process confers bacteria with the ability to establish their own virulence. Our studies have contributed to the discovery of QS, its components, and its utility as a source for genetic “cassettes” that can be imparted to cells to reprogram their function. Quorum sensing is also an outstanding “testbed” for connecting biological signaling phenomena with microfabricated devices. The communication systems are divergent: biology “communicates” with small molecules and ions, whereas devices communicate with electrons. Understanding the connectivity and translating the systems for two way communication will open many new avenues for understanding biological systems and manipulating their function. That is, a second focus of our work is on the “biofabrication” of devices that enable recapitulation and recording of biological signaling events by transducing them to electrical signals read via microfabricated chips.  We are developing an entirely new toolbox for device fabrication that builds on simple, low-cost, and reagentless assembly techniques.

Our presentation will discuss new concepts that build on synthetic biology and biofabrication as a means to interrogate information embedded in collections of small molecules. Cell constructs serve as filters, interpreters, and information amplifiers for transmission of information to abiotic signal amplifiers and finally to end users. The synergy between synthetic biology and nanomaterials will be discussed as a means for transmitting and receiving information via molecular networks.