Listeria monocytogenes is a major foodborne pathogen responsible for human listeriosis, one of the most severe infections under EU surveillance. In 2024, EFSA and ECDC reported 2,952 confirmed cases, including 1,497 hospitalizations, with a significant upward trend from 2019 to 2023, confirming its status as the fifth most reported zoonoses in the EU [1]. The pathogen primarily affects vulnerable populations such as pregnant women, individuals aged 65 years or older, and immunocompromised individuals, often leading to severe or life-threatening infections [3]. Its control is challenging due to persistence on food-associated surfaces and the ability to survive harsh conditions, including low temperature, high salt, and mild acidity, which increases the risk of contamination, particularly in meat products [2]. In this study, we investigated the adaptive responses of an L. monocytogenes serotype 1/2a strain associated with a 2022 outbreak in Italy linked to frankfurter consumption. Label-free quantitative proteomics combined with bioinformatics identified 421 proteins, of which 212 were unique to control cells (A, optimal growth conditions: NaCl 0.5%, pH 7, 37°C) and 29 uniquely expressed under stress conditions (B: NaCl 2.4%, pH 6.2, 12°C), mimicking pork product environments. Proteins in A were mainly involved in binding ions, small molecules, nucleotides, organic cyclic compounds, and ATP (FDR ranging from 1.55e-08 to 0.0016), reflecting essential metabolic and housekeeping functions. Proteins specific to B were associated with flagellar assembly, stress response, and virulence, highlighting adaptive mechanisms under environmental stress [4]. Several key proteins emerged as potential immunogenic candidates, with roles in adhesion, motility, and host interaction. These findings provide insights into L. monocytogenes adaptation to food-related stressors and identify promising targets for diagnostics and vaccine development. This knowledge can inform improved surveillance, risk mitigation, and control strategies in meat products, enhancing food safety and public health.
Unveiling stress adaptation mechanisms of Listeria monocytogenes through proteomic analysis: towards improved outbreak prevention
Luciani M.;Paparella A.;Schirone M.
2025-01-01
Abstract
Listeria monocytogenes is a major foodborne pathogen responsible for human listeriosis, one of the most severe infections under EU surveillance. In 2024, EFSA and ECDC reported 2,952 confirmed cases, including 1,497 hospitalizations, with a significant upward trend from 2019 to 2023, confirming its status as the fifth most reported zoonoses in the EU [1]. The pathogen primarily affects vulnerable populations such as pregnant women, individuals aged 65 years or older, and immunocompromised individuals, often leading to severe or life-threatening infections [3]. Its control is challenging due to persistence on food-associated surfaces and the ability to survive harsh conditions, including low temperature, high salt, and mild acidity, which increases the risk of contamination, particularly in meat products [2]. In this study, we investigated the adaptive responses of an L. monocytogenes serotype 1/2a strain associated with a 2022 outbreak in Italy linked to frankfurter consumption. Label-free quantitative proteomics combined with bioinformatics identified 421 proteins, of which 212 were unique to control cells (A, optimal growth conditions: NaCl 0.5%, pH 7, 37°C) and 29 uniquely expressed under stress conditions (B: NaCl 2.4%, pH 6.2, 12°C), mimicking pork product environments. Proteins in A were mainly involved in binding ions, small molecules, nucleotides, organic cyclic compounds, and ATP (FDR ranging from 1.55e-08 to 0.0016), reflecting essential metabolic and housekeeping functions. Proteins specific to B were associated with flagellar assembly, stress response, and virulence, highlighting adaptive mechanisms under environmental stress [4]. Several key proteins emerged as potential immunogenic candidates, with roles in adhesion, motility, and host interaction. These findings provide insights into L. monocytogenes adaptation to food-related stressors and identify promising targets for diagnostics and vaccine development. This knowledge can inform improved surveillance, risk mitigation, and control strategies in meat products, enhancing food safety and public health.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
