Stress Adaptation Responses of a Listeria monocytogenes 1/2a Strain via Proteome Profiling

Abstract

Listeria monocytogenes is a foodborne pathogen that is ubiquitous and largely distributed in food manufacturing environments. It is responsible for listeriosis, a disease that can lead to significant morbidity and fatality in immunocompromised patients, pregnant women, and newborns. Few reports have been published about proteome adaptation when L. monocytogenes is cultivated in stress conditions. In this study, we applied one-dimensional electrophoresis and 2D-PAGE combined with tandem mass spectrometry to evaluate proteome profiling in the following conditions: mild acid, low temperature, and high NaCl concentration. The total proteome was analyzed, also considering the case of normal growth-supporting conditions. A total of 1,160 proteins were identified and those related to pathogenesis and stress response pathways were analyzed. The proteins involved in the expression of virulent pathways when L. monocytogenes ST7 strain was grown under different stress conditions were described. Certain proteins, particularly those involved in the pathogenesis pathway, such as Listeriolysin regulatory protein and Internalin A, were only found when the strain was grown under specific stress conditions. Studying how L. monocytogenes adapts to stress can help to control its growth in food, reducing the risk for consumers.

Keywords: Listeria monocytogenes; foodborne disease; protein pathogenic; whole proteome.

Figure 1

List of proteins summarized by Venn diagram.

Figure 2

A network diagram created using STRING v11.05 to show the protein–protein interactions of upregulated proteins in L. monocytogenes after exposure to C2, C3, and C4 environmental stress conditions. Nodes represent proteins, while edges indicate their interactions. The edges are color-coded to represent different types of interactions, including known (pink and light blue), predicted (green, red, and blue), and other (yellow, black, and grey) interactions.