January 3, 2012
Scientists have created genetically-modified silkworms that can spin the much stronger silken threads of spiders in a technological breakthrough that promises to revolutionise the production and use of new materials made with spider silk.
For more than a quarter of a century scientists have been trying to find ways of producing industrial-scale quantities of spider silk because, weight for weight, it is stronger than steel and almost as tough as bulletproof Kevlar. A net weaved from pencil-thick rope spun from spider silk, for instance, could in theory catch a fighter jet in flight without breaking.
However, unlike the caterpillars of the silk moth Bombyx mori, spiders are territorial, aggressive and prone to cannibalism, making it impossible to rear them in the population densities required for commercial silk production.
Researchers have attempted to overcome this difficulty by transferring into silkworms the key spider genes responsible for making the silk threads used in the draglines of the golden orb-web spider. The result was a genetically-modified “transgenic” silkworm that produced a mixture of its own silk combined with the far tougher and stronger threads of spider silk within the mile-long threads of its cocoon.