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Regulatory Requirements for Staphylococcus aureus Nitric Oxide Resistance
Melinda R Grosser1, Andy Weiss2, Lindsey N Shaw2
1Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
Journal of Bacteriology
|May 18, 2016
Summary
Staphylococcus aureus resists nitric oxide (NO˙) using SarA, CodY, and Rot regulators, enabling pathogen survival. This study reveals key factors in NO˙ resistance and its link to virulence.
Area of Science:
- Microbiology
- Infectious Diseases
- Molecular Biology
Background:
- Staphylococcus aureus is a significant human pathogen.
- Nitric oxide (NO˙) is a key innate immune molecule for pathogen clearance.
- S. aureus uniquely resists NO˙, allowing its survival and pathogenesis.
Purpose of the Study:
- To identify regulatory factors enabling S. aureus resistance to nitric oxide (NO˙).
- To understand the overlap between NO˙ resistance and virulence regulation in S. aureus.
- To elucidate the mechanisms by which S. aureus survives NO˙ exposure.
Main Methods:
- Utilized a targeted transposon screen to identify genes involved in NO˙ resistance.
- Employed transcriptomics to analyze the global transcriptional response to NO˙.
- Investigated the roles of specific regulators including SarA, CodY, Rot, Fur, and SrrAB.
Main Results:
- Identified five essential regulons for NO˙ resistance: SarA, CodY, Rot, Fur, and SrrAB.
- Demonstrated that SarA, CodY, and Rot, previously unlinked to NO˙ resistance, are critical.
- Showed that S. aureus mutants lacking SarA exhibit metabolic dysfunction and transcriptional dysregulation under NO˙ stress.
Conclusions:
- Characterized the key regulatory network governing NO˙ resistance in S. aureus.
- Revealed a significant overlap between the regulation of NO˙ resistance and virulence.
- Highlighted the pleiotropic nature of S. aureus's transcriptional response to NO˙, involving metabolism and virulence.
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