title: Differential gene expression profiling of Listeria monocytogenes in Cacciatore and Felino salami to reveal potential stress resistance biomarkers.
abstract: The current study reports a) the in situ transcriptional profiles of Listeria monocytogenes in response to fermented sausage stress and b) an approach in which in situ RT-qPCR data have been combined with advanced statistical techniques to discover potential stress resistance or cell viability biomarkers. Gene expression profiling of the pathogen has been investigated using RT-qPCR to understand how L. monocytogenes responds to the conditions encountered during the fermentation and ripening of sausages. A cocktail of five L. monocytogenes strains was inoculated into the batter of Cacciatore and Felino sausages. The RT-qPCR data showed that the acidic and osmotic stress-related genes were up-regulated. The transcripts of the lmo0669 gene increased during the fermentation and ripening of Cacciatore, whereas gbuA and lmo1421 were up-regulated during the ripening of Felino and Cacciatore, respectively. sigB expression was induced in both sausages throughout the whole process. Finally, the virulence-related gene prfA was down-regulated during the fermentation of Cacciatore. The multivariate gene expression profiling analysis suggested that sigB and lmo1421 or sigB and gbuA could be used as different types of stress resistance biomarkers to track, for example, stress resistance or cell viability in fermented sausages with short (Cacciatore) or long (Felino) maturation times, respectively.
authors.affiliation: Università di Torino, Dipartimento di Scienze Agrarie, Forestali e Alimentari, Torino, Italy; Agriculture University of Athens, Department of Food Science and Technology, Laboratory of Food Quality Control and Hygiene, Athens, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Mataragas
authors.affiliation: Università di Torino, Dipartimento di Scienze Agrarie, Forestali e Alimentari, Torino, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Rovetto
authors.affiliation: Istituto Zooprofilattico Sperimentale del Pimonte, Liguria e Valle d'Aosta. - S.C. Controllo Alimenti e Igiene delle Produzioni, Torino, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Bellio
authors.affiliation: Università di Torino, Dipartimento di Scienze Agrarie, Forestali e Alimentari, Torino, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Alessandria
authors.affiliation: Università di Torino, Dipartimento di Scienze Agrarie, Forestali e Alimentari, Torino, Italy.
authors.forename: K
authors.initials: K
authors.lastname: Rantsiou
authors.affiliation: Istituto Zooprofilattico Sperimentale del Pimonte, Liguria e Valle d'Aosta. - S.C. Controllo Alimenti e Igiene delle Produzioni, Torino, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Decastelli
authors.affiliation: Università di Torino, Dipartimento di Scienze Agrarie, Forestali e Alimentari, Torino, Italy. Electronic address: lucasimone.cocolin@unito.it.
authors.forename: L
authors.initials: L
authors.lastname: Cocolin
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D005285:Fermentation; D005506:Food Contamination / Q000032:analysis*; D020869:Gene Expression Profiling; D008089:Listeria monocytogenes / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D008461:Meat Products / Q000382:microbiology*; D013312:Stress, Physiological; D013552:Swine
chemical_list: D001426:Bacterial Proteins
keywords: Fermented sausages; Gene expression; Listeria monocytogenes; RT-qPCR; Stress resistance biomarkers