Researchers discover a toxin that kills bacteria in unprecedented ways

By on September 17, 2022 0

McMaster researchers have discovered a previously unknown bacteria-killing toxin that could pave the way for a new generation of antibiotics.

The study, led by John Whitney of the Michael G. DeGroote Institute for Infectious Disease Research, shows that the bacterial pathogen Pseudomonas aeruginosa, known to cause hospital-acquired infections such as pneumonia, secretes a toxin that has evolved to kill other species of bacteria. .

Courtesy of Blake Dillon/McMaster University

John Whitney (right) and Nathan Bullen have studied this toxin for almost three years.

For Whitney, the key aspect of his discovery is not just that this toxin kills bacteria, but how it does it.

“This research is important because it shows that the toxin targets essential RNA molecules from other bacteria, effectively rendering them non-functional,” says Whitney, an associate professor in the department of biochemistry and biomedical sciences.

“Like humans, bacteria need properly functioning RNA to live.”

The author of the first study, Nathan Bullen, a graduate student in biochemistry and biomedical sciences, describes it as “a total attack on the cell” because of the number of essential pathways that depend on functional RNAs.

Whitney and Bullen, together with colleagues from Imperial College London and the University of Manitoba, studied this toxin for almost three years to understand exactly how it works at the molecular level.

This is the graphic summary of the team’s paper, “An ADP-ribosyltransferase toxin kills bacterial cells by altering structured non-coding RNAs.”

Discovery, published in the journal Molecular Cellwas made by Bullen after rigorous experimentation on common toxin targets, such as proteins and DNA molecules, before finally testing the toxin against RNA.

This finding breaks well-established precedents set by toxins targeting proteins secreted by other bacteria, such as those that cause cholera and diphtheria.

The researchers say this development holds great potential for future research that could eventually lead to new innovations that fight infection-causing bacteria.

Whitney says future antibiotic development can build on the newly discovered vulnerability.

This article has been republished with permission from the Institute for Infectious Disease Research at McMaster University. Read the original.