On July 7, 2026, scientists at the University of California, San Diego revealed a remarkable survival mechanism in bacteria, demonstrating that biofilms can eject cells to ensure their survival. This groundbreaking study, published in Nature Microbiology, was conducted by Professor Gürol Süel and his team, highlighting a previously unknown behavior in microbial communities.
Understanding Biofilm Ejection Mechanism
Biofilms, which are clusters of bacteria that adhere to surfaces, are commonly found in aquatic environments and various parts of the human body. The research team documented for the first time how communities of Bacillus subtilis, also known as hay bacillus, can forcefully eject specific cells when facing threats. “The biofilm senses that it is in trouble so it shoots cells out of the community like an escape pod,” said Professor Süel.
The ejection process is facilitated by a self-generated network of polymers called hydrogels. A key component, poly-y-glutamic acid (y-PGA), swells and propels interior cells through the outer layers of the biofilm, allowing them to swim away and colonize new locations. This discovery challenges the previous understanding that biofilms simply dissolve when facing death.
Significance of the Discovery
The ability of bacteria to eject cells serves as a survival strategy in adverse conditions, such as nutrient starvation. By releasing mobile cells, the biofilm ensures that at least some of its members have the potential to survive and thrive elsewhere. The researchers emphasized that this mechanism could have broader implications, particularly in understanding how tumors operate, as they share similarities with bacterial biofilms in terms of metastasis.
