Scientists produce synthesized materials from spider genes and E. coli
Spiders and Escherichia coli are hardly likely candidates for improving human health, but companies are now on the cusp of manufacturing spider silk commercially, with the help of E. coli. The silk is not exactly a panacea, but has a number of curious properties that make it ideal for use as artificial tendons, a substitute for copper and steel, or even as a component of bulletproof vests.
The fine strands spun by arachnids are actually a protein with an amino acid sequence comprised primarily of glycine and alanine blocks. They are antimicrobial and won’t be rejected by the human body. These qualities, according to Central Science magazine, a publication of the American Chemical Society, have led scientists to envision mass manufacture of quality wound patches, artificial tendons and coatings for implants.
Central Science also cites the silk’s potential for use as wire with conductivity comparable to copper, or a cable five times stronger than steel by weight. It has been suggested as a lifesaver not only in hospitals, but also in combat as a component in bulletproof vests.
Little wonder then that synthesizing spider silk has been Randy Lewis’ dream for the past quarter-century. Lewis is a professor of biology and biological engineering at Utah State University, where he studies the materials science, molecular biology and chemistry behind the modern-day equivalent of spinning straw into gold.
Spiders, perhaps unsurprisingly, make poor co-workers. Their cannibalistic and territorial tendencies make them impractical to farm conventionally, so scientists have been employing their genes instead. That’s where the E. coli comes in.
The term “E. coli,” though customarily coupled with “infection,” actually refers to a common bacterium native to the warm-blooded intestinal tract. According to Medical News Today, they perform a number of functions, most notably producing the vitamin K2 and protecting the intestine from other bacteria.
E. coli is now being put to use as an artificial carrier of copied spider DNA. According to Central Science, specific gene sequences are injected into E. coli cells, which are able to then synthesize the silk. It’s an imprecise art: the manufactured silk is demonstrably weaker than the spider silk it mimics.
But scientists and manufacturers haven’t given up on the tenuous technology. Currently, artificial spider silk is already in commercial production, albeit for less ambitious applications than cables and artificial tendons. AMSilk is a German company that already produces artificial spider silk proteins. According to AMSilk’s website, these are used in their cosmetic line as a component of “Spidersilk powder,” a facial cream produced by the company.
Lewis has also been working with E. coli, along with several other transgenic animals, in an attempt to make commercial spider silk production viable. According to Central Science, he’s been able to isolate silk strands from his transgenic goats’ milk, and has enabled silkworms to artificially produce superior silk, thanks to spider genes.
This wouldn’t be the first time science has turned to spiders for innovation — or even health care, as the use of antivenoms daily attests, and it may not be the last. According to Lewis, the medical field is ripe for genetic engineering. “Transgenic animals,” he says in his article in Central Science, “have already been used to make health care products.”