title: Phage receptor binding protein-based magnetic enrichment method as an aid for real time PCR detection of foodborne bacteria.
abstract: We present a novel phage receptor binding protein-based magnetic separation and pre-enrichment method as an alternative to the immunomagnetic separation methods by replacing antibodies with bacteriophage receptor binding proteins (RBPs). We couple the proposed RBP-based magnetic separation with real time PCR for rapid, sensitive and specific detection of Campylobacter jejuni cells in artificially contaminated skim milk, milk with 2% fat and chicken broth. Recovery rates, assessed by real time PCR, were greater than 80% for the samples spiked with as low as 100 cfu mL(-1) of C. jejuni cells. The specificity of capture was confirmed using Salmonella Typhimurium as a negative control where no bacteria were captured on the RBP-derivatized magnetic beads. The combination of RBP-based magnetic separation and real time PCR improved PCR sensitivity and allowed the detection of C. jejuni cells in milk and chicken broth samples without a time consuming pre-enrichment step through culturing. The total sample preparation and analysis time in the proposed RBP-based enrichment method coupled with real time PCR was less than 3 h.
authors.affiliation: Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, Canada T6G 2V4. sevoy@ualberta.ca.
authors.forename: Somayyeh
authors.initials: S
authors.lastname: Poshtiban
authors.forename: Muhammad Afzal
authors.initials: MA
authors.lastname: Javed
authors.forename: Denis
authors.initials: D
authors.lastname: Arutyunov
authors.forename: Amit
authors.initials: A
authors.lastname: Singh
authors.forename: Graham
authors.initials: G
authors.lastname: Banting
authors.forename: Christine M
authors.initials: CM
authors.lastname: Szymanski
authors.forename: Stephane
authors.initials: S
authors.lastname: Evoy
mesh_terms: D000818:Animals; D016123:Campylobacter jejuni / Q000302:isolation & purification* / Q000378:metabolism; D002417:Cattle; D002645:Chickens; D005516:Food Microbiology / Q000379:methods*; D060526:Magnetic Fields; D008892:Milk / Q000382:microbiology*; D011485:Protein Binding / Q000502:physiology; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D011991:Receptors, Virus / Q000032:analysis* / Q000378:metabolism
chemical_list: D011991:Receptors, Virus