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Updated: May 8, 2026
07:46
Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus (MRSA) in Rat
Published on: June 4, 2012
Sortase A promotes virulence in experimental Staphylococcus lugdunensis endocarditis
Simon Heilbronner1, Frank Hanses2, Ian R Monk1
1Department of Microbiology, School of Genetics and Microbiology, Trinity College Dublin, Dublin 2, Ireland.
Microbiology (Reading, England)
|August 15, 2013
Summary
Staphylococcus lugdunensis causes milder endocarditis than Staphylococcus aureus, but its genetic manipulation was hindered by a restriction-modification system. Overcoming this allows for better study of S. lugdunensis virulence factors.
Area of Science:
- Microbiology
- Infectious Diseases
- Bacterial Pathogenesis
Background:
- Staphylococcus lugdunensis is a human commensal and opportunistic pathogen causing aggressive infective endocarditis, similar to Staphylococcus aureus.
- Limited genetic tools hinder the study of S. lugdunensis virulence factors.
Purpose of the Study:
- Compare the virulence of S. lugdunensis strain N920143 to S. aureus in a rat endocarditis model.
- Develop a genetic manipulation method for S. lugdunensis to investigate its virulence factors.
Main Methods:
- Experimental rat endocarditis model comparing S. lugdunensis N920143 with S. aureus strains Newman and COL.
- Identification and characterization of a type I restriction-modification system limiting S. lugdunensis transformation.
- Construction of an E. coli strain (SL01B) for producing modified plasmid DNA to enhance S. lugdunensis transformation.
- Generation of sortase A, Fbl, and vWbl deletion mutants of S. lugdunensis N920143.
Main Results:
- S. lugdunensis N920143 induced a less severe disease course than S. aureus Newman but was comparable to MRSA strain COL.
- A type I restriction-modification system in S. lugdunensis was identified as the cause of low transformation efficiency.
- Efficient transformation of S. lugdunensis was achieved using plasmid DNA isolated from E. coli SL01B.
- A sortase A deletion mutant showed significantly reduced virulence, while Fbl and vWbl mutants displayed trends towards reduced virulence.
Conclusions:
- S. lugdunensis exhibits lower virulence than S. aureus in experimental endocarditis.
- A novel method for efficient genetic manipulation of S. lugdunensis was established by overcoming its restriction-modification system.
- Sortase A is a key virulence factor in S. lugdunensis endocarditis.
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