Electronic Thesis and Dissertation Repository


Master of Science




Dr. Rima Menassa


Shiga toxin-producing Escherichia coli (STEC) are enteropathogens colonizing the digestive tracts of humans and animals worldwide. STEC are shed in the manure of cattle and frequently contaminate beef products, vegetables, and drinking water. Immunizing cattle herds against STEC is a promising strategy to reduce STEC colonization in cattle and therefore decrease contamination in the food supply. The goal of this project is to produce a plant-made vaccine to protect ruminants against STEC. Several recombinant proteins were designed as vaccine candidates and expressed transiently in Nicotiana benthamiana and transplastomically Nicotiana tabacum. One vaccine candidate, an E. coli secreted protein A (EspA) fusion, accumulated in transplastomic lines up to 220.7 mg/kg of fresh leaf weight. Leaf tissue containing the antigen was lyophilized and will be orally administered to a small ruminant model to test vaccine efficacy.

Included in

Biotechnology Commons