A genetically engineered probiotic - a microorganism that may have health-promoting capacities - is shown to prevent and eliminate a bacterial infection in animal models in a study published in Nature Communications.
Bacteria can be genetically manipulated to kill specific pathogens. Researchers have previously engineered a laboratory strain of Escherichia coli in such a way that, in the presence of the pathogen Pseudomonas aeruginosa, the E. coli cells explode and release a toxin that selectively kills the pathogen. However, it is unclear whether this approach would work during an infection in an animal.
Matthew Chang and colleagues modify this genetic system and use it to engineer E. coli Nissle 1917, a probiotic shown to have beneficial effects on certain intestinal disorders. The modified system includes new features, such as a gene that allows the engineered microorganism to destabilize P. aeruginosa biofilms - surface-attached aggregates that can be difficult to break down. The researchers test the efficacy of the engineered probiotic in two animal models of P. aeruginosa gut infection (in mice and in the worm Caenorhabditis elegans), and find that it is more efficient in preventing the onset of an infection than in fighting a pre-established one.
The authors suggest that these engineered probiotic bacteria could be freely administered for their normal probiotic-associated benefits, while also potentially protecting against certain pathogens. Further studies would be needed to examine whether the findings can be translated to humans.