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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
Published on: May 8, 2013
Bacitracin sensing and resistance in Staphylococcus aureus
Yuuma Yoshida1, Miki Matsuo, Yuichi Oogai
1Department of Oral Microbiology, Kagoshima University Graduate School of Medical and Dental Sciences, Japan.
FEMS Microbiology Letters
|April 27, 2011
Summary
The BceRS two-component system (TCS) in Staphylococcus aureus senses bacitracin and regulates ABC transporters, influencing bacterial susceptibility to this antibiotic. This TCS controls bacitracin resistance by managing transporter expression.
Area of Science:
- Microbiology
- Bacterial genetics
- Antibiotic resistance mechanisms
Background:
- Bacterial two-component systems (TCSs) regulate gene expression, impacting virulence and antibiotic susceptibility.
- Staphylococcus aureus possesses 16 identified TCSs, some linked to antibiotic resistance.
- Previous work identified a TCS (BceRS) involved in bacitracin susceptibility.
Purpose of the Study:
- To identify factors controlled by the BceRS TCS that affect Staphylococcus aureus susceptibility to bacitracin.
- To elucidate the regulatory role of BceRS in response to bacitracin exposure.
Main Methods:
- Genetic inactivation of the BceRS TCS and identified ABC transporters.
- Analysis of bacterial susceptibility to bacitracin.
- Gene expression analysis of transporter genes under varying conditions.
Main Results:
- Two ABC transporters, BceAB and VraDE, were identified as key factors in bacitracin susceptibility.
- Inactivation of either BceRS, BceAB, or VraDE increased susceptibility to bacitracin.
- Bacitracin induced the expression of BceAB and VraDE, an effect dependent on the BceRS TCS.
Conclusions:
- The BceRS TCS acts as a sensor for bacitracin in Staphylococcus aureus.
- BceRS positively regulates the expression of the BceAB and VraDE ABC transporters.
- This regulatory pathway is crucial for mediating bacitracin resistance in Staphylococcus aureus.
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