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Updated: Jun 16, 2026
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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
cwrA, a gene that specifically responds to cell wall damage in Staphylococcus aureus
Carl J Balibar1, Xiaoyu Shen1, Dorothy McGuire1
1Department of Infectious Diseases, Novartis Institutes for BioMedical Research, 500 Technology Square, Cambridge, MA 02139, USA.
Microbiology (Reading, England)
|February 20, 2010
Summary
The Staphylococcus aureus gene cwrA is upregulated during cell wall stress and, while not affecting antibiotic resistance, is crucial for maintaining cell wall integrity and virulence in infection models.
Area of Science:
- Microbiology
- Molecular Biology
- Pathogen Research
Background:
- Staphylococcus aureus is a significant pathogen.
- A cell wall stress stimulon is known in S. aureus.
- The gene cwrA's function is largely unknown.
Purpose of the Study:
- To elucidate the biological role of cwrA in S. aureus.
- To investigate cwrA's response to cell wall stress.
Main Methods:
- Transcriptional profiling to identify stress-responsive genes.
- Antibiotic susceptibility testing (MICs).
- Phenotypic assays for cell wall integrity.
- In vivo virulence studies in a mouse sepsis model.
Main Results:
- cwrA expression increased over 100-fold upon cell wall biogenesis inhibition.
- cwrA was specifically induced by cell wall-targeting antibiotics.
- A DeltacwrA mutant showed no change in antibiotic MICs but had reduced cell wall integrity.
- The DeltacwrA mutant exhibited decreased virulence in a mouse sepsis model.
Conclusions:
- cwrA is a key component of the S. aureus cell wall stress response.
- cwrA plays a vital role in maintaining cell wall integrity.
- cwrA is important for S. aureus virulence during infection.
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