2026 Undergraduate Research Showcase

Molecular Cloning, Protein Purification, and Mutagenesis of Salmonella AB5 Toxins

Document Type

Student Presentation

Presentation Date

4-24-2026

Faculty Sponsor

Dr. Juliette Tinker

Abstract

A significant contributor to intestinal disease in bovine populations is salmonellosis. This poses considerable biological and economical challenges to the dairy industry, which can be alleviated through effective vaccine formulations. Detoxified bacterial toxins are often strong vaccine candidates and some Salmonella types such as Salmonella enterica Montevideo, Diarizonae and Typhimurium produce AB5 toxins. These proteins warrant further examination of their functional roles to determine if they can act as vaccine antigens. To initiate a deeper understanding of the toxicity and mechanisms of these proteins, we applied techniques such as molecular cloning and protein purification to isolate and purify the toxin subunits for future cellular studies. In addition to this, we performed site-directed mutagenesis of the ArtAB subunit of Salmonella enterica Typhimurium to establish the most significant active site in the sequence. The molecular cloning of S. Diarizonae B subunit and the protein purification of PltC from S. Montevideo have been successful. Mutagenesis of ArtAB is still undergoing PCR protocol optimization, but we expect to see an increase in mutant DNA that can be transformed into E. coli for purification. This mutant toxin will be used in cellular assays to help determine toxin mechanism of action. Ultimately, a safe vaccine that enhances the host’s immune response to these toxins could help mitigate drug resistance in Salmonella serovars while providing significant economical and health advantages to the dairy industry.

This document is currently not available here.

Share

COinS