Two Laboratory Activities Using Conventional or Real-Time PCR to Simulate Pathogenic <italic toggle="yes">E. coli</italic> Detection

Abstract

In these lab activities, students perform conventional PCR and real-time PCR to simulate pathogenic E. coli detection. The labs were designed to complement a previously published virtual PCR classroom activity in which students are asked to design a PCR-based diagnostic test for a pathogenic strain of E. coli. In the virtual PCR activity, students use bioinformatics to discover that the Shiga toxin genes (stx1 and stx2) are unique to the Enterohemorrhagic E. coli (EHEC) strain O157:H7. Thus they come to the conclusion that doing PCR with primers designed for shiga toxin should be able to differentiate O157:H7 from other strains of E. coli. In the lab activity described here, students actually perform the PCR assay. Performing PCR enhanced student understanding of the technique beyond what was accomplished through the virtual PCR classroom activity and is recommended as an addition to the case study.