Stephen Techtmann, a microbiologist at Michigan Technological University, and collaborators from Michigan Tech and the University of Illinois, are in the midst of a project that seems half-miraculous: turning plastic waste into edible protein. "It does kind of seem sci fi to be able to say that we're going to convert plastic into something that you can eat," Techtmann said. The secret ingredient is microbes that can feed on plastic's component parts, including a substance that resembles synthetic crude oil.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   "We would never want to feed plastic to people," Techtmann said, "but we can use microorganisms to produce biomass or proteins using plastic as an input. And so what we're trying to do with this is to take plastic, break it down, feed it to microorganisms and then recover those microbial cells as a food product."  The organization interested in the technology is the U.S. military. Most of the funding, some $7.2 million, comes from the Defense Advanced Research Projects Agency, better known as DARPA, whose past endevours are at least partly responsible for the existence of the Internet, GPS technology, self-driving cars and, on a less victorious note, the chemical defoliant Agent Orange.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     Microbes are Techtmann's specialty. Five years ago, he received a DARPA Young Faculty Award for devising a way to track the past movements of ships based on the microbes found in their bilge water. But it was his work on oil spills, begun in 2010 after the Deepwater Horizon spill in the Gulf of Mexico, that laid the groundwork for the plastics project. The first step, Techtmann said, was "looking at samples from relatively mundane places like mud from streams or compost from a nearby farm to see if there were any of these bacteria in these natural places that could do this."                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       Microbes mostly don't feed on plastic, but some do feed on the components of plastic. So part of the work is of making plastics into something microbes can eat. David Shonnard's focus is on the plastics used in the bags that contain the meals ready to eat (MRE). With a heating process called pyrolysis, the Michigan Tech chemical engineer can reduce polypropylene into a wax, a gas and an amber liquid that's something like synthetic crude oil. Rebecca Ong is also working on breaking down plastics, though she's using a chemical process not entirely dissimilar from what microbes use to break down plastics in nature. Her process is faster.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   The microbes will be both the consumers and the consumed. After they eat the deconstructed plastic, grow and multiply, they'll become the food. The idea is that they'll be dried into a powder that could be mixed into smoothies, added to animal feed, maybe someday even 3D printed into something that looks like a steak. What makes the project compelling, Techtmann said, is that it has the potential to address two big challenges, plastic waste and food insecurity, all at once. "I think what we're doing is really cool, and we're potentially going to contribute to helping to solve some of these problems," he said, "but it's going to take a lot of other people and a lot of energy and a lot of expertise."