Photo by carmenn
Five times stronger than steel, three times tougher than Kevlar, yet thinner than a human hair, spider dragline silk has long been a highly prized textile—more so than silkworm silk, even. Farming the territorial beasties, which have a proclivity for cannibalism, however, is a challenge. Although a bunch of geneticists have enlisted the aid of transgenic spider-goat hybrids to produce economically scalable amounts of the coveted fiber, researchers are recruiting a much tinier (and perhaps less controversial) host: Escherichia coli, an industrially safe bacterium commonly found in our gut.
ALONG CAME A MICROBE
Sang Yup Lee from the Korea Advanced Institute of Science and Technology, along with Young Hwan Park from Seoul National University and David Kaplan at Tufts University, turned E. coli into ersatz spiders by chemically synthesizing the silk gene and inserting it into the microbe. Once expressed, the water-soluble silk proteins are turned into insoluble fibers through spinning, much like a spider would. After culturing the hybrid spider-silk protein for mass production, the KAIST team purifies it and then spins it into lustrous silk fiber.
Researchers chemically synthesized the silk gene and inserted it intoE. coli.
Next, the KAIST team cultured the hybrid spider-silk protein for mass production, purified it, and then spun it into silk fiber. The results, according to the researchers, are virtually indistinguishable from native dragline silk, although the process is still far away from being rolled out in a factory.
The implications, though, are significant. Mass-produced silk could result in broader applications in the fields of textiles, mechanical engineering, photonics and optics, nanotechnology, and medicine. Bonus: The technique can be replicated to produce any other silk-like biomaterials, including elastin, collagen, byssus, and resilin. Who knows, maybe E. coli will someday be the new Botox.