Hirschi-Forster, Jeanallie; Mendoza, Matthew; Van Oene; Nicholas ; Payton, Jullian (Weber State University)
Faculty Advisor: Clark, Daniel (Science, Microbiology)
The purpose of this research is to obtain quantitative data about possible sources for Salmonella contamination including tributaries to the Great Salt Lake, namely, the Jordan River, Weber River, and Bear River in Utah. We will also analyze specific water and soil sources near poultry farms for possible contamination. In recent studies, there is a greater number of produce items that have been found to contribute to Salmonella outbreaks. Contaminated water used for irrigation of these crops has been implicated as the causative agent for food contamination.
Bacteria found in these waterways are enriched using selective and differential media. This means, the media provides Salmonella species with required nutrients to grow effectively while differential media inhibits the growth of non-Salmonella species. The enrichment media that is used during this process is 3 X Tryptic Soy Broth and Gram-Negative broth. Gram negative broth is used as an enrichment step, but also selective in that it inhibits growth of other organisms. The two types of differential media would be XLT4 and MSRV. Salmonella is a motile bacterium and thus branches out from its original location of inoculation. This creates a halo-like growth pattern that makes it possible to differentiate Salmonella on MSRV plates. Once Salmonella is confirmed through the MSRV and XLT4 media, sequencing of its two CRISPR loci is completed. These two chromosomal regions have been shown to be distinct in different serovars, and as such, they can be used to distinct what subspecies is present in the sample.