A new study finds that bacteria can actively block the transfer of beneficial genes to neighboring cells by using special proteins to specifically destroy shared DNA before it can spread. This challenges the long-held view that bacteria freely exchange genetic material and reveals a more competitive system in which microbes tightly control who has access to valuable traits, an insight that will help scientists better understand and potentially limit the spread of antibiotic resistance.
A new study reveals that bacteria can actively limit the spread of antibiotic resistance genes using a newly characterized mechanism that blocks DNA transfer between cells. The study, led by Professors Shigal Ben Yehuda and Ilan Rosenschein of the Hebrew University Hadassah Medical Center and published in Nature Microbiology, focused on how bacteria exchange genetic material through tiny intercellular bridges known as nanotubes, a pathway the research team had previously identified as a mode of horizontal gene transfer.
These nanotubes allow bacteria to pass plasmids, small DNA molecules that often carry antibiotic resistance genes, directly from one cell to another. Unlike classical mechanisms such as transformation and conjugation, this nanotube-mediated exchange enables close contact-dependent sharing of genetic traits in a bidirectional manner, allowing both the donor to deliver DNA and the recipient to actively acquire DNA.
New research shows that this process is not unlimited. The researchers discovered that a protein called YokF acts as a molecular “gatekeeper,” specifically blocking the movement of plasmids through nanotubes. YokF functions as an enzyme that degrades DNA during transfer, effectively preventing neighboring bacteria from acquiring potentially beneficial traits.
This mechanism allows bacteria to retain valuable genes to themselves, giving them a competitive advantage in dense microbial communities. Importantly, this study demonstrates that this nanotube-based gene transfer and its inhibition plays an important role in the spread of small plasmids with antibiotic resistance. By restricting this movement, YokF reduces the rate at which these traits move through the bacterial population.
Further analysis revealed that YokF-like proteins are widely distributed in many Gram-positive bacteria, suggesting that this is not an isolated phenomenon but a common strategy used to regulate gene flow.
The discovery highlights a previously underappreciated layer of control in bacterial evolution. Microorganisms not only share genes, but also actively control their distribution. Understanding this process could open new avenues to tackle antibiotic resistance by targeting the mechanisms that enable or limit the spread of resistance genes.
sauce:
Hebrew University of Jerusalem
Reference magazines:
Gopu, V., Others. (2026). A family of endonucleases blocks nanotube-mediated plasmid exchange. natural microbiology. DOI: 10.1038/s41564-026-02293-8. https://www.nature.com/articles/s41564-026-02293-8
