DNA From This Ugly Fish Is Being Used to Synthesize Bulletproof Slime

If you have ever seen a picture or a video of a hagfish, it's probably been on some roundup of the ocean's most horrifying creatures. But the DNA within that very creature, often known as a "slime eel," just might be the key to creating sustainable, biodegradable plastic and lighter bulletproof clothing.

The hagfish has a skull but no vertebrae or spinal chord, so scientists aren't totally sure whether to classify it as a vertebrate or not. It hasn't really changed in roughly 300 million years, which makes it a "living fossil." But this primitive sort of design is a boon for researchers who see potential in the hagfish's trademark, and arguably grossest, trait.

You see, when a hagfish is threatened, it often slimes predators—and within that slime are tiny filaments that are 100 times thinner than a human hair, yet stronger than nylon and kevlar.

Its filaments have many of the same properties as spider silk, but, genetically, it's much simpler. That made it that much easier for a synthetic biology startup in Ireland to bioengineer e. coli into making the filaments within the slime, no hagfish required.

"It's 300 million years old and hasn't really changed its design since—we think it stopped evolving, and that's why we think it's easier to get a bacteria to make it than it is to get a bacteria to make spider silk," Russel Banta, founder of the company, called  Benthic Labs, told me. "I proposed trying to synthesize spider silk, but it's just too complex to do in a cell right now and mass produce it."

He's not the first one who has had the idea—in a paper published earlier this year in Nature Communications, a researcher described how the slime is made within the hagfish, which was thought to be a breakthrough in potentially making its silk in the lab. But Banta is just having e. coli do it for him, instead.

"We found a company that synthesized the DNA for us from a genome sequence that was online, made some modifications to it so the bacteria could read it better, and put it into the e. coli," Banta told me.

The bacteria are now synthesizing two separate parts of the threads made within the slime, while Banta and his team are looking at ways to put them together, either outside the cell or within the cell itself. He says he hopes to have a breakthrough within the next week or two. From there, it's a matter of scaling it up and mass producing it.

"The gene is so simple that we can take it, put it in the bacteria 100 more times and just make the bacteria make more of it," he said. "If you can make enough of it, the things you can use it for are really endless."