Biosecurity

Viral Soldiers

Researchers on the hunt for more-effective therapies that preserve a healthy microbiome are taking a closer look at the many different viruses that attack bacteria. Bacteriophages (literally, “bacteria eaters”) punch holes through the microbes’ outer covering and inject their own genetic material, hijacking the host’s cellular machinery to make viral copies, then burst open the cell with proteins known as lysins, releasing dozens or hundreds of new phages. The cycle continues until there are no bacteria left to slay. Phages are picky eaters that only attack specific types of bacteria, so they’re unlikely to harm the normal microbiome or any human cells. And because phages have coevolved with their bacterial victims for millennia, it’s unlikely that an arms race will lead to resistance. This simple biology has led to renewed interest in the surprisingly long-standing practice of phage therapy: infecting patients with viruses to kill their bacterial foes.