Certain fatty acids are not just part of a healthy diet, they can also neutralize the harmful listeria bacterium, a new study shows. This discovery could eventually lead to improved methods to combat dangerous and drug-resistant bacteria.
Professor Birgitte Kallipolitis conducts research into dangerous bacteria at University of Southern Denmark and has led a new study that provides some surprising insights into the inner workings of the listeria bacterium. It´s a discovery that can help her and other researchers in their work to reduce the risk of dangerous bacteria in our foods.
"Our study has shown that common, naturally occurring fatty acids can switch off the specific genes that make the listeria bacterium dangerous. We tested omega-3 fatty acids, and it took them about half an hour to neutralize the listeria bacteria, says Kallipolitis.
She and her research group at the Department of Biochemistry and Molecular Biology are running several studies to try to understand exactly what happens at the molecular level when fatty acids and listeria encounter each other.
"It´s interesting that naturally occurring, completely harmless and actually healthy fatty acids can be used to suppress dangerous bacteria such as listeria. The long-term perspective is that it may prove possible to develop new treatment methods - not only against listeria, but also against other dangerous bacteria that are currently resistant to antibiotics," she said.
Researchers have long known that high concentrations of certain fatty acids may have an antimicrobial effect and can kill dangerous bacteria such as listeria and salmonella.
"Now we have discovered that something happens at even low concentrations of fatty acids, and that this is something entirely different," says Kallipolitis.
During the study, researchers observed that low concentrations of omega-3 fatty acids do not kill listeria bacteria. Instead, the specific genes responsible for their virulence, that is the capacity of the bacterium to cause disease, were switched off.
"Our theory is that the fatty acids do something to the PrfA protein so that it cannot switch on the virulence genes, and we´re very interested in finding out what exactly is occurring."
At first glance, it can sound a little troubling that the bacteria are not killed but that they are "only" rendered harmless and therefore remain alive. But this is actually an advantage.
"When the growth of the bacterium is not threatened, it does not begin to develop new survival strategies that may make it resistant to attack. Bacteria can develop resistance to attacks, and we have many examples of how this merely creates new and even bigger problems for combating them. It might be a better strategy to let them live and instead aim to neutralize their capacity to cause disease," says Kallipolitis.
A listeria infection can cause the disease, listeriosis, which can be a life-threatening illness.
The researchers have published their study in the journal Research in Microbiology.
Source: University of Southern Denmark
A Helping Hand: Innovative Approaches to Expanding Hand Hygiene Programs in Acute Care Settings
July 9th 2025Who knew candy, UV lights, and a college kid in scrubs could double hand hygiene adherence? A Pennsylvania hospital’s creative shake-up of its infection prevention program shows that sometimes it takes more than soap to get hands clean—and keep them that way.
Broadening the Path: Diverse Educational Routes Into Infection Prevention Careers
July 4th 2025Once dominated by nurses, infection prevention now welcomes professionals from public health, lab science, and respiratory therapy—each bringing unique expertise that strengthens patient safety and IPC programs.
How Contaminated Is Your Stretcher? The Hidden Risks on Hospital Wheels
July 3rd 2025Despite routine disinfection, hospital surfaces, such as stretchers, remain reservoirs for harmful microbes, according to several recent studies. From high-touch areas to damaged mattresses and the effectiveness of antimicrobial coatings, researchers continue to uncover persistent risks in environmental hygiene, highlighting the critical need for innovative, continuous disinfection strategies in health care settings.