If you’ve ever felt your teeth feel blurry after skipping a brushing, you’ve encountered biofilm, a slimy bacterial film that clings to surfaces. In medical settings, biofilms make infections more difficult to treat when they form protective shields for bacteria on devices such as catheters and implants.
UC Riverside scientists have discovered that a chemical that plants produce when they are stressed prevents the formation of biofilms. The breakthrough offers potential advances in healthcare, as well as preventing corrosion of equipment in industrial settings.
“In simple terms, biofilms are communities of microorganisms, such as bacteria or fungi, that stick together and form a protective layer on surfaces,” said Katayoon Dehesh, distinguished professor of molecular biochemistry at UCR and corresponding author of a study on the discovery.
“You’ve probably seen them as the slimy coating on river rocks or plaque on your teeth. While they are a natural part of many ecosystems, biofilms can cause big problems.”
The study, published in the journal Nature Communicationshighlights the importance of one particular metabolite, which is a molecule produced during chemical reactions that support life within plants, as well as bacteria and even some parasites, such as the one that causes malaria.
In plants, this metabolite, MEcPP, plays a critical role not only in the production of essential compounds but also in stress signaling. For example, when a plant suffers damage and too much oxygen enters its cells, it accumulates MEcPP. This molecule then triggers protective responses within the plant. The researchers discovered that this same molecule has a surprising effect on bacteria like E. coli: It disrupts the development of biofilms by interfering with their ability to adhere to surfaces.
In medical settings, biofilms grow on devices such as catheters, stents or implants, making infections more difficult to treat because the microbes in biofilms are highly resistant to antibiotics. In industrial settings, they clog pipes, contaminate food processing equipment, and cause corrosion.
“By preventing the early stages of biofilm development, this molecule offers real potential to improve outcomes in any industry that relies on clean surfaces,” Dehesh said.
Bacteria rely on hair-like structures called fimbriae to anchor themselves to surfaces, a critical step in biofilm initiation. Fimbriae help bacteria adhere to medical implants, pipes or even teeth, where they secrete a protective matrix that protects them from antibiotics and cleaning agents. Without fimbriae, biofilm formation cannot begin.
“Biofilms are like fortresses for bacteria,” said Jingzhe Guo, a UCR project scientist and first author of the paper. “By disrupting the initial binding phase, MEcPP essentially disarms the bacteria’s ability to establish these strongholds.”
Through genetic screening of more than 9,000 bacterial mutants, the research team identified a key gene called fimewhich acts as an “off switch” for fimbriae production. MEcPP improves the activity of this gene and increases the expression of fime. This, in turn, prevents bacteria from producing fimbriae and forming biofilms.
“Our discovery could inspire biofilm prevention strategies in a wide range of industries,” Guo said. “From cleaner water systems to better dental care products, the possibilities are immense.”
Biofilms are not only a medical concern but also a costly problem in industrial settings. They contribute to clogged pipes, corroded machinery, and contamination in food processing facilities. Traditional methods for managing biofilms often rely on harsh chemicals or expensive treatments, which can be harmful to the environment or ineffective over time as bacteria adapt.
“This study is a testament to the unexpected connections between plant biology and microbiology,” Guo said. “It’s exciting to think that a molecule that plants use to signal stress could one day help humans combat bacterial threats.”