Less Harmful Strains of E. Coli Help Kill off Biofilms

Escherichia coli (E. coli) bacteria commonly lives in the intestines of healthy individuals, and though most varieties of the bacteria are harmless, a few particularly nasty strains can cause especially unpleasant symptoms ranging from severe abdominal cramps to vomiting or bloody diarrhea.

Yet a recent study looks at less harmful strains of E. coli that can help fight off more deadly bacterial infections. Scientists worked to reprogram the microbe that comes from the strain in order to fight off biofilms that are responsible for many hard-to-treat infections that may actually take root in the lungs, bladder or even implanted medical devices. 

According to study author Matthew Wook Chang and colleagues, the biofilm infections are difficult to treat as the bacteria can hide under protective barriers of sugars, DNA or even proteins. This creates a shield for the bacteria that may be particularly resistant to conventional therapy, and overuse of various antibiotics can cause resistance to certain drugs.

This problem has motivated many scientists to look for alternative treatments that do not involve antibiotics and the possibility of repeat infections. For instance, in the past, researchers made bacteria that fight off other microbes, but they had limitations. Chang's team worked to address various limitations by making a new kind of bacterial component to help ward off the disease.

The researchers conclude with the following, via a press release: "They reprogrammed E. coli to sense Pseudomonas aeruginosa - a bacteria that can form biofilms and causes hospital-acquired infections in the lungs and the gut. The new E. coli then swims directly toward P. aeruginosa and launches an attack with an antimicrobial peptide and an enzyme that breaks down biofilms. Though the researchers successfully tested their engineered microbe on P. aeruginosa, they say that their engineering strategy could be used to combat other pathogens as well."

More information regarding the study can be found via the journal ACS Synthetic Biology.