7.1 Back to the soil

This is a very old problem in microbiology on cultured microorganisms. It's more than 100 years old. And people have tried to replicate the natural environment in the laboratory, and that actually didn't work very well. So we decided to do the exact opposite and simply grow them in their natural environment. And so the way we do that is we have a simple gadget, which we call a diffusion chamber. So we take a sample from soil, for example, dilute it, mix it up with agar, and instead of pouring it in a Petri dish, we sandwiched it between two semi-permeable membranes. And then this contraption, which we call diffusion chamber, that goes back into the soil where we took bacteria from. And so essentially, what that does, that tricks bacteria. Now, they don't know that something happened to them. Everything diffuses through that chamber. They get all the nutrients or growth factors from soil. And once they grow into colonies, then what we found is that with a high probability, they will then grow in a Petri dish. And now you can screen these organisms for their ability to make antibiotics.

We've been collaborating with NovoBiotic, a startup company that does a fairly massive screening using our methods. And one of their typical sources for soil is the backyard of Lucy Ling, VP of biology. And she lives in Lexington, Massachusetts. We got a very large number of anti-microbial compounds, about 30% of soil bacteria will make anti-microbials. And so the next important step is to try to figure out which are the ones that are potentially interesting and useful. And so this new compound, teixobactin, came out of that effort.