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Updated: Jul 19, 2026
11:33
Monitoring the Assembly of a Secreted Bacterial Virulence Factor Using Site-specific Crosslinking
Published on: December 17, 2013
A simple model host for identifying Gram-positive virulence factors.
D A Garsin1, C D Sifri, E Mylonakis
1Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.
Summary
The nematode Caenorhabditis elegans serves as a model for studying Gram-positive bacterial pathogens. This research identifies E. faecalis virulence factors relevant to both nematode and mammalian infections.
Area of Science:
- Microbiology
- Infectious Diseases
- Model Organisms
Background:
- Gram-positive bacterial pathogens pose significant threats to human health.
- Caenorhabditis elegans (C. elegans) is a versatile model organism for studying host-pathogen interactions.
Purpose of the Study:
- To evaluate C. elegans as a model host for human Gram-positive bacterial pathogens.
- To investigate the virulence factors of Enterococcus species in a nematode model.
- To identify novel virulence factors relevant to mammalian pathogenesis.
Main Methods:
- Infection of adult C. elegans and its developmental stages with various Gram-positive bacteria.
- Quantification of bacterial growth and nematode survival.
- Genetic manipulation of bacterial virulence factors (fsr, cytolysin, ScrB).
Main Results:
- Enterococcus faecalis, Streptococcus pneumoniae, and Staphylococcus aureus were found to be lethal to adult C. elegans.
- E. faecalis and Enterococcus faecium caused mortality in C. elegans eggs and hatchlings.
- E. faecalis established persistent intestinal infections in adult worms.
- The E. faecalis fsr system and cytolysin were crucial for nematode killing.
- The nematode model facilitated the identification of E. faecalis ScrB as a virulence factor relevant to mammalian pathogenesis.
Conclusions:
- C. elegans is a facile and inexpensive model for studying Gram-positive bacterial infections.
- Nematode infection models can reveal conserved virulence mechanisms applicable to mammalian pathogenesis.
- This study identified E. faecalis ScrB as a potential target for therapeutic intervention.
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