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Involvement of B. pseudomallei RpoS in apoptotic cell death in mouse macrophages

I Lengwehasatit1, A Nuchtas, S Tungpradabkul

  • 1MU-OU:CRC and Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand. scilw@mahidol.ac.th

Microbial Pathogenesis
|November 21, 2007
PubMed

Insights

The RpoS protein of Burkholderia pseudomallei is crucial for inducing cell death in mouse macrophages. A mutant lacking RpoS failed to cause cytotoxicity, indicating RpoS

Area of Science:

  • Microbiology
  • Cell Biology
  • Immunology

Background:

  • Burkholderia pseudomallei causes melioidosis and can survive within host cells.
  • This bacterium is known to induce apoptosis in various cell types.

Purpose of the Study:

  • To investigate the role of the RpoS protein in Burkholderia pseudomallei-induced apoptosis.
  • To determine if RpoS is essential for the bacterium's cytotoxic effects on macrophages.

Main Methods:

  • Comparison of wild-type B. pseudomallei and an rpoS mutant strain.
  • Assessment of cytotoxicity in mouse macrophage cell lines (RAW264.7).
  • Measurement of mitochondrial membrane potential and caspase-3 activation.

Main Results:

  • The B. pseudomallei rpoS mutant strain showed significantly reduced cytotoxicity compared to the wild-type.
  • The mutant induced less pronounced changes in mitochondrial membrane potential.
  • Caspase-3 activation was lower in macrophages exposed to the rpoS mutant.

Conclusions:

  • RpoS plays a critical role in Burkholderia pseudomallei's ability to induce apoptosis in mouse macrophages.
  • The RpoS protein is essential for the bacterium's cytotoxic effects and regulation of cell death pathways.

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