Researchers at Boston University have discovered that a small number of drug-resistant "Good Samaritan" bacteria may help other, more vulnerable microbes survive antibiotic treatments, even if they themselves don't, according to Scientific American's Melinda Wenner Moyer. The researchers exposed a culture of E. coli to increasing amounts of antibiotics over time and saw that, although the entire population was doing well despite the presence of the drug, only a few individual microbes were actually drug resistant, Moyer says. It turns out that the resistant bugs were secreting indole, a molecule which stunted their own growth but helped the rest of the population survive. The researchers hope that this finding could lead scientists to develop better antibiotics, perhaps by blocking indole, Moyer adds.