Title: Development of an oligonucleotide-based microarray to detect multiple foodborne pathogens Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 1, 2009
Publication Date: N/A
Technical Abstract: Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes and Campylobacter jejuni are considered important foodborne bacterial pathogens causing the most food-related human illnesses worldwide. Current methods for pathogen detection have limitations in effectively identifying multiple foodborne pathogens. In this study, a pathogen detection microarray was developed using various 70-mer oligonucleotides specifically targeting the above pathogens. To reduce the cost of detection, each microarray chip was designed and fabricated to accommodate 12 identical arrays which could be used for screening up to 12 different samples. To achieve high detection sensitivity and specificity, different DNA amplification approaches including target-specific multiplex PCR, random PCR and whole genome amplification were compared by hybridizing amplicons to the detection array. The target-specific multiplex PCR simultaneously amplified 14 targets from all of the above pathogens in a single reaction tube which significantly improved the detection efficiency and specificity. Combined with multiplex PCR amplification, the microarray unambiguously distinguished all of the pathogens with a detection sensitivity of 1x10-4 ng (approximately 20 copies) of each genomic DNA. This method greatly expands the capability to simultaneously detect multiple foodborne pathogens. Moreover, the microarray analysis also provided important information of virulence determinants of interest.