Brazil’s Atlantic coast could be a hotspot for novel antibiotics (Image: Radius Images/Getty)

A global grassroots effort to map the genetic riches of soil is under way. It may sound mundane, but the aims are lofty: to turn up bacteria that yield new types of antibiotics. Already, the hard work is paying off. Participants have identified an area in New Mexico and an Atlantic forest region in Brazil as being particularly rich in potentially useful bacterial genes.

Scientists and volunteers from five continents are helping Sean Brady of the Rockefeller University in New York and his colleagues with their Drugs from Dirt project. So far, they have collected 185 soil samples and extracted DNA from them. To work out which samples are the most biochemically diverse, they compared the DNA with that from lab-grown bacteria known to produce a wide range of important and interesting chemicals.

Bacterial hotspots

The project forms part of Brady’s mission to map interesting microbial DNA worldwide, so that the search for much-needed new antibiotics can home in on the most promising regions. “We’d like to use this info to target the best sites,” says Brady.


Brady says around a quarter of their samples so far have been contributed by citizen scientists, without which the project would be too expensive to run. Volunteers are asked to take a couple of spoonfuls of earth, bag them and send them to Brady’s lab.

The collection of samples currently numbers a few hundred – far fewer than the thousands Brady aims to collect – but they have already yielded some interesting results. Genes found in samples from both New Mexico and Brazil may encode alternative versions of known anti-cancer molecules, including bleomycin, an important antibiotic used to kill cancerous cells.

Hunt for the best

The preliminary map of bacterial biodiversity follows the discovery of teixobactin, a new antibiotic discovered in a soil bacterium by Kim Lewis at Northeastern University in Boston, Massachusetts, and his colleagues. They identified the substance after developing a method that coaxes bacteria previously thought to be unculturable to grow in the lab.

Brady says his microbial map can help researchers like Lewis find the best versions of new antibiotic compounds. “They found a rare compound that does a really neat thing – but maybe it’s not the best one that nature made,” says Brady.

To get involved with the project, sign up at drugsfromdirt.org

Journal reference: eLife, DOI: 10.7554/eLife.05048