title: Novel PCR Assays Complement Laser Biosensor-Based Method and Facilitate Listeria Species Detection from Food.
abstract: The goal of this study was to develop the Listeria species-specific PCR assays based on a house-keeping gene (lmo1634) encoding alcohol acetaldehyde dehydrogenase (Aad), previously designated as Listeria adhesion protein (LAP), and compare results with a label-free light scattering sensor, BARDOT (bacterial rapid detection using optical scattering technology). PCR primer sets targeting the lap genes from the species of Listeria sensu stricto were designed and tested with 47 Listeria and 8 non-Listeria strains. The resulting PCR primer sets detected either all species of Listeria sensu stricto or individual L. innocua, L. ivanovii and L. seeligeri, L. welshimeri, and L. marthii without producing any amplified products from other bacteria tested. The PCR assays with Listeria sensu stricto-specific primers also successfully detected all species of Listeria sensu stricto and/or Listeria innocua from mixed culture-inoculated food samples, and each bacterium in food was verified by using the light scattering sensor that generated unique scatter signature for each species of Listeria tested. The PCR assays based on the house-keeping gene aad (lap) can be used for detection of either all species of Listeria sensu stricto or certain individual Listeria species in a mixture from food with a detection limit of about 10⁴ CFU/mL.
authors.affiliation: Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA. kpkim@jbnu.ac.kr.|Department of Food Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonbuk 561756, Korea. kpkim@jbnu.ac.kr.
authors.forename: Kwang-Pyo
authors.initials: KP
authors.lastname: Kim
authors.affiliation: Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA. aksingh@purdue.edu.
authors.forename: Atul K
authors.initials: AK
authors.lastname: Singh
authors.affiliation: Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA. bai16@purdue.edu.
authors.forename: Xingjian
authors.initials: X
authors.lastname: Bai
authors.affiliation: Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA. l.leprun@laposte.net.
authors.forename: Lena
authors.initials: L
authors.lastname: Leprun
authors.affiliation: Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA. bhunia@purdue.edu.|Department of Comparative Pathobiology, Purdue University, West Lafayette, IN 47907, USA. bhunia@purdue.edu.
authors.forename: Arun K
authors.initials: AK
authors.lastname: Bhunia
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D005516:Food Microbiology / Q000379:methods*; D057230:Limit of Detection; D008087:Listeria / Q000235:genetics* / Q000302:isolation & purification*; D058889:Molecular Typing / Q000379:methods*; D016133:Polymerase Chain Reaction / Q000379:methods*; D025341:Principal Component Analysis
chemical_list: D004269:DNA, Bacterial
keywords: BARDOT; Listeria adhesion protein; Listeria species; PCR; alcohol acetaldehyde dehydrogenase; detection