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Intracellular parasitism and molecular determinants of Legionella virulence

Y Belyi1

  • 1Gamaleya Research Institute of Epidemiology and Microbiology, Moscow, Russia. bel@gamem.msk.su

International Microbiology : the Official Journal of the Spanish Society for Microbiology
|December 8, 2000
PubMed

Insights

Legionella bacteria are pathogens that invade host cells, disrupting normal cell functions to survive and replicate. Understanding Legionella

Area of Science:

  • Microbiology
  • Cell Biology
  • Pathogenesis

Background:

  • Legionella are significant human pathogens that exhibit intracellular parasitic behavior.
  • These bacteria infect host cells, interfering with crucial cellular processes like phagocytosis.

Purpose of the Study:

  • To elucidate the molecular mechanisms by which Legionella establishes intracellular parasitism.
  • To identify bacterial factors contributing to Legionella virulence.

Main Methods:

  • Utilized biological, biochemical, and molecular-genetic approaches.
  • Investigated bacterial products potentially involved in virulence.
  • Examined effects on host cell processes such as oxidative burst, phagosome acidification, maturation, and organelle trafficking.

Main Results:

  • Legionella binding to host cells triggers complex disruptions in phagocytosis.
  • Identified potential virulence factors including cytotoxins, enzymes, and export machinery proteins.
  • Observed inhibition of oxidative burst, reduced phagosome acidification, blocked maturation, and altered organelle trafficking.

Conclusions:

  • Legionella actively manipulates host cell machinery to evade destruction and create a replicative niche.
  • Despite progress, the precise molecular mechanisms of Legionella intracellular parasitism remain incompletely understood.

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