Israeli scientists have developed tiny “tweezers” capable of breaking down defenses that bacteria build to survive the human immune system.
In a bid to stay alive and reproduce in humans, bacteria construct biofilms — shields to protect themselves against the immune system that is programmed to try to destroy them.
Such protection helps many infection-causing bacteria survive. It’s also the mechanism that bacteria use to live in our mouths — part of dental plaque is a biofilm that helps bacteria survive underneath despite our toothbrushing. Biofilms are also grown by bacteria in plants, animals and other environments.
Researchers at Ben Gurion University of the Negev, with collaborators from the US and Germany, now say they have built “molecular tweezers” that pull the biofilm apart, breaching the bacteria-built defenses.
“The tweezers are just like your home tweezers but a million times smaller, and instead of plucking hairs they attack fibers of the bacteria’s biofilm,” Prof. Raz Jelinek of Ben Gurion’s chemistry department told The Times of Israel. “By doing that they break the biofilm, making it more vulnerable to human immune defenses and external substances that are used against bacteria like antibiotics.”
Together with his PhD student Ravit Malishev, he tested the tweezers, made from small organic molecules, in an in-vitro lab experiment on Staphylococcus aureus (staph) bacteria. The study was is reported upon in a newly peer-reviewed article in the journal Cell Chemical Biology.
Jelinek said the tweezers successfully breached more than 80% of biofilms they were tested on.
He observed that fighting staph infections could save many lives, as they have an estimated mortality rate in the US of over 25 percent, and as much as 40% for drug-resistant strains.
If further tests pan out, Jelinek said that the tweezers could be packaged in pills. The pills would release the tweezers once in the body. “You would swallow a pill that contains millions of sets of these molecular tweezers, which would look around for biofilms and break them apart.”
This could then allow the immune system to more easily eliminate illness-inducing bacteria as well as enable drugs to more effectively tackle the invaders.
Molecular tweezers, molecules programmed with a grabbing function, aren’t a new invention. They have shown promise in inhibiting various harmful substances including proteins that are believed to cause Alzheimer’s, and are used in drugs that are in development.
“We did not invent molecular tweezers. The novelty here is we have shown they can be used as an antibacterial substance,” said Jelinek.
He added that the ability to allow the immune system to better do its job could reduce reliance on antibiotics and the problems that creates. “The important thing about creating antibacterials that attack the biofilm rather than the bacteria is that they eliminate the risk of the bacteria developing antibiotic resistance, as the bacteria aren’t being directly attacked,” he said.
“Because of this, we’re using a really good strategy in terms of challenging antibiotic resistance.”