Sensors, memory switches, and circuits can be encoded in a common gut bacterium.
(July 9, 2015) The “friendly” bacteria inside our digestive systems are being given an upgrade, which may one day allow them to be programmed to detect and ultimately treat diseases such as colon cancer and immune disorders.
In a paper published today in the journal Cell Systems, researchers at MIT unveil a series of sensors, memory switches, and circuits that can be encoded in the common human gut bacterium Bacteroides thetaiotaomicron.
These basic computing elements will allow the bacteria to sense, memorize, and respond to signals in the gut, with future applications that might include the early detection and treatment of inflammatory bowel disease or colon cancer.
Researchers have previously built genetic circuits inside model organisms such as E. coli. However, such strains are only found at low levels within the human gut, according to Timothy Lu, an associate professor of biological engineering and of electrical engineering and computer science, who led the research alongside Christopher Voigt, a professor of biological engineering at MIT.
“We wanted to work with strains like B. thetaiotaomicron that are present in many people in abundant levels, and can stably colonize the gut for long periods of time,” Lu says.
The team developed a series of genetic parts that can be used to precisely program gene expression within the bacteria. “Using these parts, we built four sensors that can be encoded in the bacterium’s DNA that respond to a signal to switch genes on and off inside B. thetaiotaomicron,” Voigt says.