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Secreted bacterial phospholipase A2 enzymes: better living through phospholipolysis

Izabela Sitkiewicz1, Kathryn E Stockbauer, James M Musser

  • 1Center for Molecular and Translational Human Infectious Diseases Research, The Methodist Hospital Research Institute, Houston, TX 77030, USA.

Trends in Microbiology
|December 30, 2006
PubMed

Insights

Certain bacterial phospholipase A2 (PLA2) enzymes, like ExoU and SlaA, enhance pathogen fitness and spread by modulating host responses. This increases the population of PLA2-positive strains, improving their chances of infecting vulnerable hosts.

Area of Science:

  • Microbiology
  • Enzymology
  • Pathogen Biology

Background:

  • Phospholipases are enzymes that modify cell membranes, inflammation, and signaling.
  • Bacterial pathogens can acquire genes for secreted phospholipase A2 (PLA2) enzymes via lateral gene transfer.
  • ExoU from Pseudomonas aeruginosa and SlaA from Streptococcus pyogenes are key examples.

Purpose of the Study:

  • To investigate the role of bacterial secreted PLA2 enzymes in host-pathogen interactions.
  • To understand how enzymes like ExoU and SlaA influence disease severity and host responses.
  • To propose a function for these enzymes in enhancing bacterial strain fitness.

Main Methods:

  • Literature review of studies on bacterial PLA2 enzymes.
  • Analysis of known functions of ExoU and SlaA in pathogenesis.
  • Hypothesizing the evolutionary advantage conferred by these enzymes.

Main Results:

  • Secreted PLA2 enzymes modulate host inflammatory and signaling pathways.
  • ExoU and SlaA contribute to increased disease severity.
  • These enzymes alter host-pathogen interactions in favor of the pathogen.

Conclusions:

  • ExoU and SlaA enhance the fitness of bacterial subclones expressing them.
  • Increased enzyme expression boosts the population of PLA2-positive strains.
  • This provides an advantage for pathogen transmission to susceptible hosts.

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