Start Date
April 2026
Location
2nd floor - Library
Abstract
Escherichia coli is a type of bacteria which lives within the intestines of warm-bloodedanimals and is often used as a biological marker to show fecal contamination within water.Numerous health issues can arise from drinking or swimming in water contaminated withE. coli, especially Shiga-toxin producing strains. Traditional methods used for detecting E.coli include culturing on differential and selective media. However, culturing is time-consuming and has low sample throughput. Alternatively, traditional PCR can be used to quickly identify bacterial species by detecting specific subsets of genes. Quantitative PCR(qPCR) is a more sensitive version of PCR, which can also provide an accurate quantification of bacteria present in the sample. In this project, regular and SYBR Green qPCR have been used to verify primers and test for the CydA, lacY, and yDiv genes,which are present in all E. coli strains. Additionally, primers for Stx1 and Stx2 were designed and tested to differentiate Shiga-toxin producing E. coli (STEC) from control strains. Currently, TaqMan probes have been designed and are being used to produce more sensitive qPCR results. Once the method for the TaqMan probe is finalized and results are successful, the environmental water samples can be tested using either of the qPCR methods.
A qPCR method to detect various strains of Escherichia coli in environmental samples
2nd floor - Library
Escherichia coli is a type of bacteria which lives within the intestines of warm-bloodedanimals and is often used as a biological marker to show fecal contamination within water.Numerous health issues can arise from drinking or swimming in water contaminated withE. coli, especially Shiga-toxin producing strains. Traditional methods used for detecting E.coli include culturing on differential and selective media. However, culturing is time-consuming and has low sample throughput. Alternatively, traditional PCR can be used to quickly identify bacterial species by detecting specific subsets of genes. Quantitative PCR(qPCR) is a more sensitive version of PCR, which can also provide an accurate quantification of bacteria present in the sample. In this project, regular and SYBR Green qPCR have been used to verify primers and test for the CydA, lacY, and yDiv genes,which are present in all E. coli strains. Additionally, primers for Stx1 and Stx2 were designed and tested to differentiate Shiga-toxin producing E. coli (STEC) from control strains. Currently, TaqMan probes have been designed and are being used to produce more sensitive qPCR results. Once the method for the TaqMan probe is finalized and results are successful, the environmental water samples can be tested using either of the qPCR methods.
