Retired USU biology professor Randy Lewis garnered international attention a decade ago for his development of “Spider-Goats,” whose milk produces two key proteins used for making large quantities of spider silk.
His synthetic biomaterials lab is now lead by Assistant Professor Justin Jones, who is taking it in a new direction, one without the famous spider goat.
“Even when you think about satisfying some of the smallest applications for spider silk, you would have to have a tremendously large goat herd in order to satisfy those applications. It just became too inefficient to continue,” said Jones.
Because it’s so strong and light, spider silk has many applications, from military defense to medicine. So there is a big interest in mass producing it in a simpler way. One of the most promising methods Jones and his colleagues have explored is production in silkworms.
“When you ask a goat, or you ask a bacteria to produce spider silk for you, all you get is the raw protein powder, then you have to formulate it into a fiber or some other material form. Whereas silkworms have very similar systems of spinning silk, and an industry exists and has existed for 1000s of years to raise silkworms,” said Jones.
Silkworms offer a replacement to “Spider-Goats” but in terms of yield they’re still limited. Therefore, Jones says they have turned to investigating the slime of hagfish and the proteins they contain.
“They're called intermediate filaments. And when you isolate them from the slime, you stretch them and allow them to dry, they have very nearly the mechanical properties of spider silk. So they're very, very strong,” said Jones.
Hagfish proteins can also replicate faster in bacteria. For example, E.coli expressing hagfish DNA can produce four to eight times the amount of protein than has ever been recovered in spider silk production.
Jones’ team is also looking at the biomaterials of other aquatic animals called ctenophores, known as Comb jellyfish.
“And while we still do spider silk research, right now, that's a fairly minor part of our portfolio,” said Jones.
He adds that the focus of his research currently is on the biomaterials of these aquatic creatures.
