The Role of Background Bacteria in Preventing the Isolation and Detection of Shigella and STEC in Foods and Novel MuSIC ddPCR Method to Improve STEC Detection in the Presence of Background Bacteria

It appears your Web browser is not configured to display PDF files. Download adobe Acrobat or click here to download the PDF file.

Click here to download the PDF file.

Creator: 

McMahon, Tanis

Date: 

2018

Abstract: 

Foodborne illness caused by Enterohemorrhagic E. coli (EHEC) and Shigella remain a public health issue in developed countries. The current microbiological methods for detecting EHEC and Shigella typically involve an enrichment step that aims to amplify the pathogenic organisms relative to the background bacteria flora present in foods. Following enrichment, there is a screening step to identify pathogens based on presence of virulence genes (ex. stx and eae for EHEC). False-positive detection of EHEC can occur if virulence targets are present within the population of bacteria found in foods, but not in any single organism. In this study, a Multiplexed Single Intact Cell ddPCR (MuSIC ddPCR) was developed to reduce the false-positives in the EHEC method. During enrichment, EHEC and Shigella are often outcompeted by non-target bacteria. The role of microbial antagonism of non-target bacteria in preventing growth of EHEC and Shigella in enrichment culture was also investigated.

Subject: 

Microbiology
Biology - Molecular

Language: 

English

Publisher: 

Carleton University

Thesis Degree Name: 

Master of Science: 
M.Sc.

Thesis Degree Level: 

Master's

Thesis Degree Discipline: 

Biology

Parent Collection: 

Theses and Dissertations

Items in CURVE are protected by copyright, with all rights reserved, unless otherwise indicated. They are made available with permission from the author(s).