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Measuring Bacterial Load and Immune Responses in Mice Infected with Listeria monocytogenes
Published on: August 9, 2011
Listeria monocytogenes protein p60 affects hemolytic activity and uptake of bacteria by macrophages
A Krawczyk-Balska1, Z Markiewicz, J Bielecki
1Department of General Microbiology, Faculty of Biology, University of Warsaw, Poland. akra@biol.uw.edu.pl
Abstract:
Bacillus subtilis strains expressing listeriolysin O (LLO) and simultaneously LLO and p60 protein were constructed. The effect of p60 protein on hemolytic activity and on the invasion of professional phagocytes was demonstrated in the absence of other virulence factors of L. monocytogenes. The hemolytic activity of LLO in the presence of p60 protein decreased which indicates that p60 promoted adhesion and subsequent invasion of professional phagocytes.
Insights
The p60 protein in Bacillus subtilis reduces listeriolysin O (LLO) hemolytic activity. This suggests p60 enhances bacterial adhesion and invasion of phagocytic cells, independent of other L. monocytogenes virulence factors.
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Molecular Biology
Background:
- Listeria monocytogenes virulence factors are crucial for infection.
- Listeriolysin O (LLO) is a key hemolytic toxin contributing to L. monocytogenes pathogenesis.
- The role of other L. monocytogenes proteins in modulating LLO activity requires further investigation.
Purpose of the Study:
- To investigate the effect of the p60 protein on the hemolytic activity of LLO.
- To determine if p60 influences the invasion of professional phagocytes by Bacillus subtilis.
- To elucidate the role of p60 in bacterial adhesion and invasion in the absence of other L. monocytogenes virulence factors.
Main Methods:
- Construction of Bacillus subtilis strains expressing listeriolysin O (LLO).
- Co-expression of LLO and p60 protein in Bacillus subtilis.
- Assessment of hemolytic activity in the presence and absence of p60.
- Evaluation of bacterial invasion into professional phagocytes.
Main Results:
- Hemolytic activity of LLO was decreased in the presence of p60 protein.
- p60 protein promoted adhesion of Bacillus subtilis to professional phagocytes.
- p60 facilitated the subsequent invasion of professional phagocytes by Bacillus subtilis.
Conclusions:
- The p60 protein modulates the hemolytic activity of LLO.
- p60 plays a role in enhancing bacterial adhesion and invasion of phagocytes.
- These findings highlight a novel function of p60 in bacterial pathogenesis, independent of other L. monocytogenes virulence factors.
