Zhang, Yulan (2012-02). Salmonella Infection on Arabidopsis Seedlings Requires Both Host and Pathogen Factors. Master's Thesis. Thesis uri icon

abstract

  • Human enteric pathogen Salmonella contaminates raw produce and triggers significant economic loss and illness. Under a natural environment, Salmonella resides in soil and enters the interior of plants without causing disease or eliciting symbiotic growth. Upon being consumed by humans, complex virulence mechanisms are elicited by the specific intestine conditions, such as high temperature and humidity and lead to profound infection. The lack of effective prevention and drug treatment are largely attributed to the unclear mechanistic understanding on Salmonella association with environmental media, and in vivo host and pathogen factors required for persistent infection. We have explored the potential of deploying the model plant organism Arabidopsis thaliana to tackle this fundamental yet clinically challenging question, as Arabidopsis possesses many advantages as a model system, including enriched genomic resources, powerful genetic tools, low maintenance cost and a large collection of individual gene deletion mutants. Our preliminary data demonstrated Arabidopsis seedlings under liquid culture conditions mimicking the intestine environment were infected and killed by salmonella within 2 days upon inoculation. The Arabidopsis system possesses well-developed genetic information and the resources to study host factors required for infection on very short time scales, thus complementing traditional animal genetic studies. We aim to define the pathogen factors required for this infection. By merging the fields of extremely powerful Arabidopsis genetics and bacterial genetics/genomics, we hope to provide insight into possible new paradigms for addressing salmonella-mediated food born infection.

publication date

  • December 2010