An essential role of a ferritin-like protein in acid stress tolerance of Listeria monocytogenes

Abstract

The expression of ten genes of Listeria monocytogenes previously identified as penicillin G-inducible was transcriptionally analyzed in the presence of 0.5 M KCl, pH 5.0 and 42 °C. This study revealed that all the genes are upregulated by osmotic stress, seven by acid stress and four by temperature stress conditions. The contribution of a gene encoding a ferritin-like protein (fri), a two-component phosphate-response regulator (phoP) and an AraC/XylS family transcription regulator (axyR) to temperature, acid and osmotic stress tolerance was further examined by analysis of nonpolar deletion mutants. This revealed that a lack of PhoP or AxyR does not affect the ability to grow under the tested stress conditions. However, the Δfri strain showed slightly delayed growth under osmotic and clearly impaired growth under acid stress conditions, indicating an important role of the ferritin-like protein in acid stress tolerance.

Comparative transcriptomic analysis of Listeria monocytogenes reveals upregulation of stress genes and downregulation of virulence genes in response to essential oil extracted from Baccharis psiadioides

“…The results obtained in the present study confirm this, since the fur gene was downregulated, and, consequently, the fri gene was upregulated in the presence of EOBp. A recent study demonstrated that the cell-envelope stress response in L. monocytogenes is linked to the osmotic stress response, confirming the results obtained in the present work, because active terpenes compounds present in EOBp act by binding the cell membrane of microorganisms (Milecka et al 2015). Several studies suggest that Fri has a global impact on the L. monocytogenes regulatory network (Dussurget et al 2005;Olsen et al 2005), and this protein is also a mediator of beta-lactam tolerance and resistance to antibiotics such as cephalosporins (Krawczyk-Balska et al 2012).…”

The intrinsic cephalosporin resistome of Listeria monocytogenes in the context of stress response, gene regulation, pathogenesis and therapeutics

“…; Milecka et al . ). Susceptibility studies revealed that a knockout of gene fri resulted in a two‐fold increase in sensitivity to cephradine and cefalotin and further analysis demonstrated that under β ‐lactam pressure Fri is required to maintain proper level of expression of the dlt operon, which is responsible for d ‐alanylation of cell wall teichoic acids, thus providing an appropriate net charge of the cell wall (Krawczyk‐Balska et al .…”

“…Fri of L. monocytogenes is not a sensu stricto regulator protein; however, in the fri mutant strain significant changes in the content of the global regulators anti-sigma B factor (RsbW) and catabolite control protein A (CcpA) were observed, thus suggesting that Fri has a global impact on the L. monocytogenes regulatory network . Fri was shown to contribute to virulence, and mediate the resistance of L. monocytogenes to iron-starvation, cold-and heat-shock, oxidative and low pH stress Olsen et al 2005;Milecka et al 2015). Susceptibility studies revealed that a knockout of gene fri resulted in a two-fold increase in sensitivity to cephradine and cefalotin and further analysis demonstrated that under b-lactam pressure Fri is required to maintain proper level of expression of the dlt operon, which is responsible for D-alanylation of cell wall teichoic acids, thus providing an appropriate net charge of the cell wall (Krawczyk-Balska et al 2012a; Krawczyk-Balska and Lipiak 2013).…”

Comparative Proteomics of Schistosoma Japonicum Developed From Different Oncomelania Snails Permissive Areas

“…Increased expression of mitochondrial ferritin provides new insights into the antioxidant role of ferritin in the brains of Alzheimer's disease (AD) patients [45]. A Listeria monocytogenes ferritin-like protein plays an essential role in acid stress tolerance [46][47]. Our study showed that ferritin plays an important role in the iron metabolic pathway of S. japonicum (Sup Figure 8).…”