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Methods to Inhibit Bacterial Pyomelanin Production and Determine the Corresponding Increase in Sensitivity to Oxidative Stress
Published on: August 31, 2015
YhgC protects Bacillus anthracis from oxidative stress
Madanahally D Kiran1, Shashi Bala, Miriam Hirshberg
1Tufts University, Cummings School of Veterinary Medicine, North Grafton, MA - USA.
The International Journal of Artificial Organs
|October 7, 2010
Summary
Bacillus anthracis YhgC protein is crucial for bacterial survival under oxidative stress and macrophage infection. Inhibiting YhgC may reduce anthrax
Area of Science:
- Microbiology
- Molecular Biology
- Pathogenesis
Background:
- Bacillus anthracis causes lethal inhalational anthrax and is a potential bioweapon.
- YhgC in bacilli is structurally similar to TRAP, a stress response protein in staphylococci.
Purpose of the Study:
- To investigate the role of YhgC in Bacillus anthracis stress tolerance and virulence.
- To understand the regulatory mechanisms influenced by YhgC.
Main Methods:
- Gene deletion of yhgC in B. anthracis Sterne strain.
- Immunolocalization, phenotypic analysis, transcriptomics, and proteomics studies.
Main Results:
- YhgC localizes to the cell surface and cytoplasm.
- YhgC enhances oxidative stress tolerance and in vitro macrophage infection.
- YhgC negatively regulates Class I and III stress response genes (hrcA and ctsR regulons).
- YhgC positively regulates ClpP-2 and camelysin expression.
Conclusions:
- YhgC is vital for B. anthracis survival under oxidative stress.
- Targeting YhgC could impair B. anthracis survival within the host.
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