title: Expression of Listeria monocytogenes key virulence genes during growth in liquid medium, on rocket and melon at 4, 10 and 30 °C.
abstract: The aim of the present study was to assess the expression of key virulence genes, during growth of a Listeria monocytogenes isolate in liquid medium, on melon and rocket at different temperatures and time. For that purpose, BHI broth, rocket and melon were inoculated at 7.0-7.5 log CFU mL(-1) or g(-1)and stored at 4, 10 and 30 °C. Sampling took place upon inoculation and after 0.5, 6 and 24 h of incubation. The RNA was stabilized and the expression of hly, plcA, plcB, sigB, inlA, inlB, inlC, inlJ, lmo2672 and lmo2470 was assessed by RT-qPCR. The results obtained were summarized into two observations; the first one referring to the interactive effect of incubation temperature and type of substrate and the second one to the effect of time on gene expression. Regarding the latter, nearly all genes were regulated upon inoculation and exhibited differential expression in the subsequent sampling times indicating the existence of additional regulatory mechanisms yet to be explored.
authors.affiliation: Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, GR-118 55 Athens, Greece.
authors.forename: Agni
authors.initials: A
authors.lastname: Hadjilouka
authors.affiliation: Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, GR-118 55 Athens, Greece.
authors.forename: Christina
authors.initials: C
authors.lastname: Molfeta
authors.affiliation: Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, GR-118 55 Athens, Greece.
authors.forename: Olga
authors.initials: O
authors.lastname: Panagiotopoulou
authors.affiliation: Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, GR-118 55 Athens, Greece.
authors.forename: Spiros
authors.initials: S
authors.lastname: Paramithiotis
authors.affiliation: Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, GR-118 55 Athens, Greece.
authors.forename: Marios
authors.initials: M
authors.lastname: Mataragas
authors.affiliation: Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, GR-118 55 Athens, Greece. Electronic address: ehd@aua.gr.
authors.forename: Eleftherios H
authors.initials: EH
authors.lastname: Drosinos
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D031216:Barbarea / Q000382:microbiology*; D019662:Cucurbitaceae / Q000382:microbiology*; D003470:Culture Media / Q000032:analysis*; D005638:Fruit / Q000382:microbiology*; D015964:Gene Expression Regulation, Bacterial; D008089:Listeria monocytogenes / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D013696:Temperature; D037521:Virulence Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D037521:Virulence Factors
keywords: Liquid medium; Listeria monocytogenes; Melon; Rocket; Virulence genes