Noah Souza

Using a Salmonella Protein to Reduce Foodborne Illness

Abstract

In the U.S., non-typhoidal Salmonella (NTS) is a major cause of foodborne illness, hospitalization, and death. NTS infects both humans and animals and largely causes gastroenteritis or inflammation of the stomach and intestines. Despite increased efforts to control Salmonella infection through government-backed programs, including the development of vaccines for specific animals, NTS incidence rates have not significantly declined. Part of this is due to the high virulence and antibiotic resistance of some NTS strains. Therefore, there is a major need to create a broadly cross-protective vaccine for NTS. Our lab has recently purified a Salmonella AB5 protein, called ‘ArtAB’, and tested it on epithelial cells, which serve as a barrier function in your body. We observed similar characteristics and activity of ArtAB to other well-researched AB5 proteins. The family of AB5 proteins are promising vaccine components that are secreted by gram-negative bacteria. These proteins are characterized by an enzymatically active A-subunit and a pentameric binding B-subunit. In a typical infection, the B-subunit will undergo binding to specific receptors on host cells, allowing for the A-subunit to alter cell signaling and ultimately trigger cell death. AB5 proteins have well-described adjuvant activity or ability to stimulate the immune system. Due to the toxicity of the A-subunit, B5 subunits are of great interest. We hypothesize that ArtB, the B-subunit of ArtAB, can act as an immune-stimulatory agent in future vaccines to combat NTS. We plan to use a variety of experimental techniques to see how ArtAB (contains both subunits) and ArtB (B-subunit alone), will comparatively stimulate the immune system.