While many people may envision a desktop, laptop, tablet, or even a smartphone when thinking about what a computer is, the truth is that anything that performs a computation is a computer. People can be computers, mechanical machines can be computers, and genetic material can be computers too. Now researchers at Washington University in St. Louis have created the largest genetic circuit yet out of different kinds of bacteria.
The circuit itself behaves like an AND gate as it responds to different molecules with it in a solution. With enough of the correct molecules present, the circuit is activated and a protein is released to trigger some response. This response could be to release a medicine in the body, or start a reaction to break down chemical waste, or something else altogether. The circuit itself is made of pieces from three different bacteria, specifically Shigella flexneri, Pseudomonas aeruginosa and Salmonella typhimurium. The reason for the three bacteria is to minimize crosstalk when molecules bind to more than just the intended logic gate.
Though this may not lead to a biological computer you could play Crysis on, it could enable extraordinary biological tools. The ability to program when specific actions occur within cells could revolutionize many kinds of biotechnology.