Development and application of Peptide Nucleic Acid Fluorescence in situ Hybridization for the specific detection of Listeria monocytogenes

• Type: Article in International Scientific Journal
• Date: 2019

Authors

Rui Rocha (Author) Other; José M. Sousa (Author) Other; Laura Cerqueira (Author) FEUP; Nuno F. Azevedo (Author) FEUP

Journal

Title: Food Microbiology

Vol. 80

Pages: 1-8

ISSN: 0740-0020

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 28 Citations

Associated Projects

LEPABE-2-ECO-INNOVATION - LEPABE-2-ECO-INNOVATION

LEPABE - Laboratório de Engenharia de Processos, Ambiente, Biotecnologia e Energia

Coded-FISH - Desenvolvimento de um novo método de RING FISH codificado por cores: uma ferramenta inovadora para a deteção de patogénios resistentes a antibióticos

Other information

Authenticus ID: P-00Q-59X

DOI: 10.1016/j.fm.2018.12.009

Abstract (EN): Listeria monocytogenes is one of the most important foodborne pathogens due to the high hospitalization and mortality rates associated to an outbreak. Several new molecular methods that accelerate the identification of L. monocytogenes have been developed, however conventional culture-based methods still remain the gold standard. In this work we developed a novel Peptide Nucleic Acid Fluorescence in situ Hybridization (PNA-FISH) method for the specific detection of L. monocytogenes. The method was based on an already existing PNA probe, LmPNA1253, coupled with a novel blocker probe in a 1:2 ratio. The method was optimized for the detection of L. monocytogenes in food samples through an evaluation of several rich and selective enrichment broths. The best outcome was achieved using One Broth Listeria in a two-step enrichment of 24 h plus 18 h. For validation in food samples, ground beef, ground pork, milk, lettuce and cooked shrimp were artificially contaminated with two ranges of inoculum: a low level (0.2-2 CFU/25 g or mL) and a high level (2-10 CFU/25 g or mL). The PNA-FISH method performed well in all types of food matrices, presenting an overall accuracy of 99% and a detection limit of 0.5 CFU/25 g or mL of food sample.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8