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Development and Assessment of Intracellular Infection Models for Staphylococcus aureus
Published on: January 17, 2025
Prevalence of agr dysfunction among colonizing Staphylococcus aureus strains
Bo Shopsin1, Alex Drlica-Wagner, Barun Mathema
1Department of Medicine, New York University School of Medicine, New York, NY, USA. shopsin@saturn.med.nyu.edu
The Journal of Infectious Diseases
|August 30, 2008
Summary
Agr-defective Staphylococcus aureus strains can colonize healthy individuals, suggesting they are fit for survival. These strains may be transmitted within families and selected in hospitals.
Area of Science:
- Microbiology
- Infectious Diseases
- Genetics
Background:
- The accessory gene regulator (agr) is a key virulence regulator in Staphylococcus aureus.
- Agr mutations are common during S. aureus infections, but their role in colonization is unclear.
Purpose of the Study:
- To investigate the colonization fitness of agr-defective Staphylococcus aureus strains in healthy humans.
- To determine the transmissibility and potential selection pressures for agr-defective S. aureus.
Main Methods:
- Screening of 160 healthy subjects for S. aureus colonization.
- Assays to detect delta-hemolysin activity and agr autoinducing peptide production to identify agr-defective strains.
- Analysis of strain identity in family members and association with hospitalization.
Main Results:
- Approximately 9% of healthy subjects were colonized with agr-defective S. aureus or mixed strains.
- Identical agr-defective strains were found in family members, indicating transmissibility.
- Carriage of agr-defective strains was associated with hospitalization, suggesting nosocomial selection.
Conclusions:
- Agr-defective Staphylococcus aureus strains possess colonization fitness in the human population.
- Agr-defective strains are transmissible and may be selected for in healthcare settings.
- Further research is needed to understand the clinical implications of agr-defective S. aureus colonization.
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