A U.S. biotechnology firm has spun the first batch of "Dragon Silk," a genetically modified spider silk fiber, as part of a supplier agreement with the U.S. Army.
The fiber was created by Kraig Biocraft Laboratories at its production site in Indiana, and is now headed to a reeling facility to be prepared for delivery to partner firm Warwick Mills, which will incorporate the fiber into military gear.
Kraig says its Dragon Silk is the strongest and most elastic recombinant spider silk it has created among more than a dozen genetically engineered spider silk fibers based on the company’s genetic designs. Both Dragon Silk and Monster Silk, a sister product, are spun by lines of transgenic silkworms. They are composed of a combination of spider silk protein and silkworm silk protein.
These genetically engineered spider silks are significantly stronger and more flexible than commercial grade silk, according to Kraig, and have applications in both technical textile and apparel markets. For the Army work, Kraig has contracted with Warwick Mills to produce ballistic shoot packs using the fiber.
Kraig’s genetic engineering technology is applied principally to the domesticated silkworm. The silkworm is suited to produce genetically engineered spider silk, the company says, because the silkworm already is an efficient producer of silk, with 40% of the caterpillar’s weight devoted to the silk glands. These glands produce large volumes of protein, called fibroin, which are then spun into a composite protein silk thread.
Kraig says that genetically engineered spider silk, with its mechanical characteristics, eventually can surpass the current generation of high-performance fibers used in a variety of military, industrial, and consumer applications where strength, toughness and flexibility are required.