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dc.contributor.advisor Gallegos, Dr. Maria
dc.contributor.advisor Lauzon, Dr. Carol
dc.creator Teuscher, Kristen
dc.date 2016-12-01
dc.date.accessioned 2019-01-26T00:48:14Z
dc.date.available 2019-01-26T00:48:14Z
dc.date.issued 2016-12-01
dc.identifier.uri http://hdl.handle.net/10211.3/207807
dc.description.abstract For my thesis research, I analyzed three different possible capabilities of certain STECs (Shiga toxin-producing Escherichia coli) to determine if any or all of these capabilities might be used for improved detection protocols. All of these capabilities can be easily visualized on bacteriological media rather quickly, i.e, within 24 h. The first capability involved the potential susceptibility of certain STECs to a bacteriophage. I refer to this examination as a “biological detection method. ” Bacteriophages are viruses that infect bacteria. I tested the ability of a bacteriophage to infect certain STECs known to infect non-pathogenic E. coli. I want to see if STECs have a defense mechanism against predators such as a bacteriophage, which may add to their virulence or if they can be destroyed in a phage assay. I also surveyed certain STECs for the ability to produce products associated with biochemical pathways, such as siderophore and quorum sensing compound production and to see if these abilities are correlated with toxin production. Siderophores are ironchelating compounds that sequester iron from the environment and bring them into the bacterial cell (Garénaux et al., 2011). Iron is used in bacterial cells for functions such as cell growth, enzyme production (peroxidase and superoxide dismutase), and metabolism (toxins, vitamins, tricarboxylic acid cycle, and electron transport) (Messenger & Barclay, 1983). I aim to determine if siderophore detection could be used to differentiate stains of STEC from each other O157:H7 E. coli. Finally, I tested for the production of quorum sensing compounds. Gram-negative bacteria communicate with each other through quorum sensing compounds, particularly acyl-homoserine lactones (Shaw et al., 1997). Studies have shown that quorum sensing compounds influence the expression of virulence factors (Natrah et al., 2011; Le Berre et al., 2008) including toxin production. My research similarly aimed to determine if certain STECs produce quorum-sensing compounds and if their production can be used to differentiate strains of STEC from each other and from O157:H7 E. coli. en_US
dc.language English en_US
dc.subject Escherichia coli en_US
dc.title Novel Approaches to Detect and Differentiate Pathogenic E. coli en_US
dc.type Thesis en_US
dc.contributor.primaryAdvisor Curr, Dr. Kenneth
thesis.degree.name Master of Science in Biological Science en_US

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