Controlling Organisms Electrically with Synthetic Biology

Since both organisms and devices use electrons as information and energy carriers, interfacing living cells with electrodes offers the opportunity to control key biological processes electronically. I will describe our efforts to engineer bi-directional electronic communication between living cells and non-living systems by installing electron nanoconduits into cell membranes. We have recently demonstrated that by transplanting synthetic genes into the model organism Escherichia coli we can express these electron nanoconduits and confer upon these cells the ability to reduce metal ions, solid metal oxides, and electrodes. Additionally, current production by engineered E. coli causes these cells to shift their metabolism towards more oxidized products, demonstrating that this electronic interface can control intracellular state. Lastly, we have shown that these E. coli can accept, as well as donate, electrons from an electrode. Thus, this work provides a blueprint for electron conduits which bi-directionally move energy and information between living cells and non-living systems, and has direct applications in bioenergy, bioremediation, biosynthesis, biosensing, and biocomputing.