Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Biological Engineering

Committee Chair(s)

Randy Lewis


Randy Lewis


Ron Sims


Jon Takemoto


Spider silk has received significant attention due to its fascinating mechanical properties. Given the solitary and cannibalistic behavior of spiders, spider silk farming is impractical. Unlike spiders, silkworms are capable of producing large quantities of a fibrous product in a manner mimetic to spiders, and there already exists an industry to process cocoons into threads and textiles for many applications. The combination of silk farming (sericulture), a millennia old practice, and modern advancements in genetic engineering has given rise to an innovative biomaterial inspired by nature; transgenic silkworm silk.

This project focuses on the creation of chimeric silkworm-spider silk fibers through the genetic modification of silkworms. Advanced genetic engineering techniques were used to introduce the minor ampullate spider silk (MiSp) genes into the silkworm genome. A subset of these transgenic silkworms was cross-bred with other transgenic silkworms containing the same spider silk gene in a different section of the silkworm genome to create hybrid, dual-transgenic silkworms. The transgenic silk samples showed increased mechanical properties compared to native silkworm fibers, with the strongest fibers approaching or surpassing the mechanical properties of native spider silk. The transgenic silk retained the elasticity of the native silkworm silk and gained the strength of the spider silk. Ultimately, genetic engineering opens the door to mass produce synthetic spider silk in an established organism and industry, and the results of this project demonstrate that the properties of silkworm silk can be predictably altered through this technology.