Wow of the week: With a little bioengineering, E. coli becomes a pathogen-fighting superhero

E. coliScientists in Singapore think there might be a way to fight microorganisms that cause infection with, well, other microorganisms that cause infection.

Synthetic biologist Matthew Chang and his colleagues at Nanyang Technological University in Singapore bioengineered E. coli bacteria in a way that causes them to hunt down and kill the gram negative bacterium Pseudomonas aeruginosa. It’s a frequent cause of hospital-acquired infections like pneumonia and bloodstream infections.

In a paper published in the latest issue of ACS Synthetic Biology, the group fed their pumped-up E. coli to mice infected with P. aeruginosa and, a few hours later, found fewer pathogens in their feces.

According to an article in Nature this week, Chang sees potential for eventual use in humans as a preventative measure for people at risk of infection. The E. coli would remain dormant in the gut, only to be activated by the presence of P. aeruginosa.


Here’s how it works. The scientists inserted genes into E. coli that would make it secrete a killing peptide called microcin S. Then they loaded it with genes that make a nuclease that can slice through to protective film that envelops colonies of the bacteria. Finally, they programmed the E. coli so that it’s activated by the presence of a certain P. aeruginosa messenger molecule.

While similar methods have been studied and developed in the past, University of Maryland synthetic biologist Wiliam Bentley is quoted by Nature as saying that this approach is “really innovative” and unique in that no one has ever put all of these mechanisms together.

[Image credit: Rocky Mountain Laboratories, NIAID, NIH]