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Updated: May 23, 2026
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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
Staphylococcus aureus isolates belonging to different multilocus sequence types present specific virulence gene
Ricardo Pinto Schuenck1, Fernanda Sampaio Cavalcante, Eduardo Emery
1Departamento de Patologia, Universidade Federal do Espirito Santo, Vitória, Espirito Santo, Brazil.
FEMS Immunology and Medical Microbiology
|March 27, 2012
Summary
This study characterized Staphylococcus aureus isolates from a Rio de Janeiro hospital, finding specific lineages and virulence genes linked to infections. Methicillin resistance was common in certain sequence types (STs).
Area of Science:
- Microbiology
- Infectious Diseases
- Genetics
Background:
- Staphylococcus aureus is a significant cause of hospital-acquired infections.
- Understanding the genetic diversity and virulence factors of S. aureus is crucial for infection control.
Purpose of the Study:
- To characterize Staphylococcus aureus isolates from orthopedic infections in Rio de Janeiro.
- To investigate SCCmec types, clonality, and virulence genes.
- To correlate genetic profiles with methicillin resistance and specific sequence types (STs).
Main Methods:
- Pulsed field gel electrophoresis (PFGE) for clonality assessment.
- Multilocus sequence typing (MLST) to determine sequence types (STs).
- Detection of SCCmec types and specific virulence genes (e.g., fnbB, bbp, pvl).
Main Results:
- Twenty-eight percent of isolates were methicillin-resistant, with SCCmec types IV and III being most common.
- Five major lineages (STs 239, 1, 5, 30, and 1462) comprised 83.5% of isolates.
- Specific virulence genes (fnbB, bbp, pvl) were associated with STs 239, 30, and 30/1462.
- STs 1, 5, and 30 exhibited distinct virulence profiles regardless of methicillin resistance.
Conclusions:
- Dominant S. aureus lineages and virulence factors were identified in orthopedic infections.
- Methicillin resistance is associated with specific STs and SCCmec types.
- Understanding these genetic characteristics aids in targeted infection control strategies.
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