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Updated: May 14, 2026
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A Non-Coding Small RNA MicC Contributes to Virulence in Outer Membrane Proteins in Salmonella Enteritidis
Published on: January 27, 2021
ROS-sensing transcription factor YchJ regulates RssB-RpoS pathway to protect Salmonella against oxidative attack by
Weiwei Wang1,2,3, Xilu Yuan1,3, Yumeng Xiao4
1Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.
Nature Communications
|May 12, 2026
Summary
Salmonella uses a novel protein, YchJ, to manage oxidative stress and survive inside host cells. YchJ activates antioxidant defenses by controlling RpoS stability, independent of the known OxyR system.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Bacterial pathogens face oxidative stress within host phagocytes.
- Canonical antioxidant systems like OxyR are known, but alternative pathways are poorly understood.
Purpose of the Study:
- To identify and characterize novel redox-sensitive regulators in bacterial oxidative stress response.
- To elucidate the mechanism by which Salmonella survives oxidative stress independently of OxyR.
Main Methods:
- Genetic deletion of ychJ in Salmonella.
- Proteomic analysis to identify downstream targets.
- Electrophoretic mobility shift assays (EMSAs) to confirm DNA binding.
- Structural analysis of YchJ.
- Dual-transcriptome analysis.
Main Results:
- YchJ is a redox-sensitive transcription factor coordinating an antioxidant defense system.
- YchJ represses rssB, leading to RpoS accumulation and upregulation of antioxidant enzymes (SodC, KatE).
- YchJ directly binds the rssB promoter; ROS sensing involves reversible dimerization via a disulfide bond.
- YchJ activates Salmonella's antioxidant defenses and disrupts host pathways during infection.
Conclusions:
- YchJ represents a previously unrecognized redox-sensing pathway crucial for bacterial virulence.
- This study uncovers a novel transcriptional mechanism controlling RpoS stability and bacterial stress response.
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