New Understanding of Persistent Bacteria Could Lead to More Effective Antibiotics

Hebrew University researchers say they've discovered the mechanism by which some bacteria are able to withstand antibacterial treatment, arguing that their study could lead to new ways to control the bull-headed pests.

Some bacteria are able to withstand antibiotics via mutation, while others, known as "persistent bacteria" aren't so much resistant to treatment as they are able to avoid it by slipping into a dormant state until the antibiotics are gone, at which point they reemerge.

Such bacteria have long posed a problem to researchers who knew there was some kind of link between them and a naturally occurring toxin in the bacteria known as HipA. The toxin's cellular toxin and how its activity causes the bacteria to play dead have both been less clear, however.

A new study led by Gadi Glaser of Hebrew University's Faculty of Medicine and Nathalie Balaban of the Racah Institute of Physics offers a solution to both of these.

According to their research, when antibiotics first mount their attack on the bacteria, the HipA toxin disrupts the chemical messaging process that nutrients need in order to build proteins. The bacteria interpret this as a hunger signal, prompting them to switch into a dormant state. They then remain in this state until the antibiotics are gone, at which point they begin wreaking havoc again.

The study is not the first on persistent bacteria, or "persisters," to come out of Balaban's lab, which has focused on developing a better understanding of the phenomenon for several years now. By combining the latest study with another currently carried out by Glaser on combating the bacteria, the researchers hope to develop a more effective treatment for bacterial infections.

"When you treat using antibiotics, there will always be some bacteria that survive," Glaser told Haaretz. "If we manage in the future to introduce a substance that deals with the biological mechanism that the study uncovered, antibiotics will be more effective."

Published in the journal Nature, the study included contributions from Dr. Irine Ronin and doctoral students Ilana Kaspy, Eitan Rotem and Noga Weiss.