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Modulation of a "CD59-like" protein in Naegleria fowleri amebae by bacteria

Angela E Fritzinger1, Francine Marciano-Cabral

  • 1Department of Microbiology and Immunology, Virginia Commonwealth University, Medical College of Virginia Campus, Richmond, Virginia 23298, USA.

The Journal of Eukaryotic Microbiology
|November 13, 2004
PubMed

Insights

Naegleria fowleri, a pathogen causing Primary Amebic Meningoencephalitis, expresses a CD59-like protein. This protein may protect the ameba from bacterial predators and toxins, as evidenced by intact amebae after co-culture.

Area of Science:

  • Microbiology
  • Parasitology
  • Immunology

Background:

  • Naegleria fowleri causes fatal Primary Amebic Meningoencephalitis in humans.
  • N. fowleri possesses a surface protein similar to mammalian CD59, a complement-regulatory protein.
  • The function of this CD59-like protein in N. fowleri is currently unknown.

Purpose of the Study:

  • To investigate the expression of the N. fowleri "CD59-like" protein in response to bacterial stimuli.
  • To elucidate the potential role of this protein in amebic survival against bacterial predation and toxins.

Main Methods:

  • Western immunoblot analysis was used to detect protein expression.
  • Co-culture experiments with N. fowleri and bacteria (Escherichia coli, Pseudomonas aeruginosa).
  • Electron microscopy was employed to examine amebae-bacteria interactions.

Main Results:

  • Differential expression of the "CD59-like" protein was observed when N. fowleri was co-cultured with E. coli or P. aeruginosa.
  • N. fowleri amebae remained intact after co-culture with bacteria, suggesting resistance.

Conclusions:

  • The "CD59-like" protein in N. fowleri may play a protective role against bacterial predators.
  • This protein could be involved in defending the ameba against bacterial toxins.
  • Further research is warranted to fully understand the function of this protein in N. fowleri pathogenesis.

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