Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Biological Engineering

Committee Chair(s)

H. Scott Hinton


H. Scott Hinton


Ronald C. Sims


Randy Lewis


Charles Miller


Spider silk has the potential to be a useful biomaterial due to its high tensile strength and elasticity. It is also biocompatible and biodegradable, making it useful for wound dressings and sutures, tissue and bone scaffolds, vessels for drug delivery, and ligament and tendon replacements. In some studies where spider silk has been used to grow cells, the silk has promoted more cell growth than the control. However, it is difficult to obtain the high volume of silk needed for these undertakings on a large scale. Spiders are territorial and cannibalistic, so they cannot be easily farmed. Therefore, spider silk proteins are frequently produced in other organisms. E. coli is often used for spider silk production due to the relative ease of gene manipulation and the cost effectiveness of large-scale fermentation. However, due to the large protein size of the spider silk and the repeating amino acid motifs, there are some challenges with production in E. coli.

Metabolic modeling is a way to model the metabolism of an organism and can help overcome some of the difficulties of spider silk production in E. coli by predicting metabolic engineering strategies. In this study, a metabolic modeling tool known as dynamic FBA predicted that ammonium is depleted during cell growth. Laboratory results confirmed that by adding additional ammonium to the medium, the E. coli cells experienced more cell growth and were able to produce more spider silk protein