Biologists from the Massachusetts Institute of Technology (MIT) have modified gut bacteria to render them “more useful”: they have succeeded in turning the microorganisms into intestinal health monitors which can even alert of any anomaly.
MIT researchers have managed to switch on and off the genes of the abundant gut microorganism known as Bacteroides thetaiotaomicron. The latter were re-engineered to perform certain functions when they were administered into the gut of a mouse.
“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,” said Christopher Voigt, an MIT biological engineer and study senior author, in a statement.
The bacteria in question has properties that make of them ideal for long-term treatments: they are stable in the gut and will not get destroyed by the immune system; they interact with human cells as well as other microbes for long time periods; furthermore, they are found in great numbers to be able to use them for science.
The bacteria were made to sense and report certain conditions in the gut like bleeding and inflammation. Upon detecting the anomalies, the bacteria glow as a way of “alerting” of the problem.
Furthermore, the new bacteria as per their new functions can be controlled based on the food consumed by the individual.
“The culmination of the work is not only do you have an engineered bacterium that’s colonized the mouse gut, but you can turn on which genes in the bacterium are active based on what you feed the mouse,” explained Voigt. “That’s really something new. It allows you to control what the bacterium is doing at the site of where it’s operating.”
The treatment cannot as yet be translated in the human gut. For now, the biologists have only managed to experiment on mice guts. More research needs to be done to make the transition from animal alimentary system to ours.
“The big picture is that the bacteria that live in us or on us impact human health in very significant ways and the existing techniques we have to modulate the microbiome – taking antibiotics or changing our diet – are relatively limited,” said Timothy Lu, the second senior author. “We’re hoping that with these tools to precisely engineer the intimate interface between bacteria and humans we’re going to be able to tackle some major health-related problems.”