Leopold Green

DNA’s double-helical structure is so well-recognized that the image has become synonymous with the idea of science. But this structure can be coiled, squished, and folded to create all sorts of shapes. By creating synthetic DNA, scientists can twist and fold the structures like origami.

Leopold Green, 34, is specifically interested in creating tubes, which have the benefit of allowing things to pass through them. Put these tubes into cells, and proteins or other chemicals could get in or out, potentially changing the way the cells work.

Green, a synthetic biologist at Purdue University, has developed a way to create DNA nanotubes using microscopic tiles of DNA. These tiles can join together to form tubes, and can grow or shrink. “It’s a beautiful balance of art and science and engineering,” he says.

Green wants to use this approach to tackle chronic diseases, many of which are linked to atypical immune responses. What if we could harness “good” microbes that happily reside inside us to dampen those responses? Green’s lab developed a strain of E. coli Nissle, a microbe that has been used as a probiotic, that can secrete a protein that influences the way our immune cells work. If microbes like these can be developed to sense signals of disease and respond to them—through nanotubes embedded in their membranes—they could “help push the system in the right direction,” says Green.

For a condition like eczema, researchers might focus on skin microbes. But Green is also studying microbes found in the vaginal tract. And microbes could be altered to target a range of other body cells—including those in the brain. In theory, researchers could take a microbe from a person’s body, modify it, and then reintroduce it as a probiotic-like therapy. “That’s my long-term vision,” says Green.