It’s well known how bacteria exposed to antibiotics for long periods will find ways to resist the drugs—by quickly pumping them out of their cells, for instance, or modifying the compounds so they’re no longer toxic.
Now new research has uncovered another possible mechanism of antibiotic “resistance” in soil. In a paper published on Dec. 6 in the Journal of Environmental Quality, a group of Canadian and French scientists report on a soil bacterium that breaks down the common veterinary antibiotic, sulfamethazine, and uses it for growth.
Certain soil bacteria are already known to live off, or “eat,” agricultural pesticides and herbicides, says the study’s leader, Ed Topp, a soil microbiologist with Agriculture and Agri-Food Canada in London, Ontario. In fact, the microbes’ presence in farm fields can cause these agrichemicals to fail.