It is known that bacterial cells exchange biological matter, but it is not clear whether bacteria can exchange functional proteins. In a recent paper published in Science on June 25, 2026, researchers from Baylor College of Medicine and their collaborators investigated horizontal protein transfer between bacteria, specifically between protein-donor Escherichia coli and protein-receiving E. coli that could turn into persister cells and tolerate lethal antibiotic doses or a stressful environment.