When Gautam Dantas first observed bacteria eating antibiotics, he was sure there had to be some mistake. The year was 2007, and he was trying to coax microbes to turn plant waste into biofuels. Dantas was a postdoctoral researcher in the Harvard University lab of George Church, a pioneer in genetics research. As part of his investigation, Dantas had exposed one group of soil microbes to a dose of antibiotic, which he figured the bacteria wouldn’t eat. A week later, a group grown on a diet of plant matter — and exposed to no antibiotics — had grown only a little. In the dishes filled with antibiotic, however, most of the microbes were having a picnic. Instead of proving deadly, the antibiotics were providing sustenance.
“We figured we’d probably made a mistake,” Dantas recalls a decade later. He’s now a professor of pathology, immunology and biomedical engineering at Washington University, managing a lab with more than a dozen researchers studying everything from biofuel production to the human microbiome. But the mystery of those antibiotic-eating bacteria has remained a personal obsession.
Earlier this year, after hundreds of experiments, Dantas finally published his solution in Nature Chemical Biology. What he discovered provides important insights into antibiotic resistance, the precipitous increase in bacterial immunity to what should be killer drug doses. Public health officials now consider it a medical crisis. Every year, some 700,000 deaths are attributed to pathogens that are resistant to penicillin and other drugs designed to kill them — largely in response to overprescription and careless disposal. With any luck, Dantas’ hungry bacteria will help, by preventing resistance from evolving in the first place.
