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Using Mycobacterium smegmatis as a Bioindicator for Zinc-Limited Growth Conditions in Mycobacteria
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Using Mycobacterium smegmatis as a Bioindicator for Zinc-Limited Growth Conditions in Mycobacteria

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Porins limit the intracellular persistence of Mycobacterium smegmatis

Soroush Sharbati-Tehrani1, Joachim Stephan2, Gudrun Holland1

  • 1Robert Koch-Institut, Nordufer 20, 13353 Berlin, Germany.

Microbiology (Reading, England)
|July 8, 2005
PubMed

Insights

Deleting porin genes in Mycobacterium smegmatis enhances its ability to survive inside host cells. This suggests that the outer membrane

Area of Science:

  • Microbiology
  • Cell Biology
  • Immunology

Background:

  • Mycobacterium species display varied abilities to persist within host cells.
  • The mycobacterial outer membrane's role in intracellular survival is not fully understood.

Purpose of the Study:

  • To investigate the impact of outer membrane permeability on intracellular persistence of Mycobacterium smegmatis.
  • To determine if porin deletions affect mycobacterial survival in eukaryotic cells.

Main Methods:

  • Generated Mycobacterium smegmatis mutants with deletions in porin genes mspA and mspC.
  • Assessed intracellular persistence of wild-type and mutant strains in murine macrophages and Acanthamoeba castellanii.
  • Complemented the mspA deletion to confirm gene function.

Main Results:

  • Deletion of both mspA and mspC significantly enhanced intracellular persistence.
  • Complementation restored wild-type levels of persistence.
  • Outer membrane permeability is critical for M. smegmatis intracellular survival.

Conclusions:

  • Porin-mediated permeability of the mycobacterial outer membrane is essential for limiting intracellular persistence.
  • Targeting porins could be a strategy to control mycobacterial infections.

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