Submitted to: Journal of Microbiological Methods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/20/2002
Publication Date: 5/2/2003
Citation: Call, D.R., Borucki, M.K., Loge, F.J. Detection of bacterial pathogens in environmental samples using DNA microarrays. Journal of Microbiological Methods. 2003. v. 53. p. 235-243. Interpretive Summary: This manuscript gives a brief overview of microarray technology and summarizes the various ways microarray technology can be used to detect bacterial pathogens from environmental samples. Additionally, data from a Listeria monocytogenes subtyping microarray is used to illustrate the potential of microarrays for bacterial subtyping and identification of diagnostic markers.
Technical Abstract: Polymerase chain reaction (PCR) is an important tool for pathogen detection, but historically it has not been possible to accurately identify PCR products without sequencing, Southern blots, or dot-blots. Microarrays can be coupled with PCR where they serve as a set of parallel dot-blots to enhance product detection and identification. Microarrays are composed of many discretely located probes on a solid substrate such as glass. Each probe is composed of a sequence that is complimentary to a pathogen specific gene sequence. PCR is used to amplify one or more genes and the products are then hybridized to the array to identify species-specific polymorphism within one or more genes. We illustrate this type of array using 16S rDNA probes suitable for distinguishing between several salmonid pathogens. We also describe the use of microarrays for direct detection of either RNA or DNA without the aid of PCR, although the sensitivity of these systems currently limits their application for pathogen detection. Finally, microarrays can also be used to "fingerprint" bacterial isolates and they can be used to identify diagnostic markers suitable for developing new PCR-based detection assays. We illustrate this type of array for subtyping an important food-borne pathogen, Listeria monocytogenes.