A novel biomarker for detection of Listeria species in food processing factory

摘要

A biomarker-based PCR amplification method has been proved to be an effective tool for rapid and accurate detection of Listeria contamination in food factories. However, the current biomarkers (such as iap, hly genes) used for the detection of Listeria have a problem of detection efficiency for some Listeria species, including 7 recently recognized species. Therefore, in this study, a new comprehensive biomarker was developed for the effective detection of all Listeria species. The study employed a novel in-silico scheme to explore and characterize the alternative biomarkers. Biomarker BE-LisAll was identified against 34 Listeria and over 2700 other bacterial complete genomes by in-silico scheme. Specificity of biomarker BE-LisAll was then evaluated with 17 different Listeria species and 58 non-Listeria bacteria isolates. The result showed 100% specificity to Listeria species, and the biomarker could differentiate Listeria species from a variety of non-Listeria bacteria. Finally, the PCR amplification with BE-LisAll was compared with the conventional culture method for detection of Listeria spp. using 60 swab samples collected from a food-processing factory to verify the biomarker's applicability. The result demonstrated 100% correspondence to the results of the conventional culture method. The BE-LisAll biomarker-based PCR amplification is presented for rapid and comprehensive detection of all Listeria species with a high degree of accuracy and sensitivity. It is hoped that commercial food processing industries are able to employ this developed biomarker as a Listeria-detection tool in their factories to prevent or reduce economic losses due to Listeria contamination. (C) 2016 Elsevier Ltd. All rights reserved.