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Characterization of a novel porin involved in systemic Yersinia enterocolitica infection

Shirly Mildiner-Earley1, Virginia L Miller

  • 1Department of Molecular Microbiology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, MO 63110, USA.

Infection and Immunity
|June 23, 2006
PubMed

Insights

Researchers discovered a new protein, systemic factor protein A (SfpA), in Yersinia enterocolitica. This protein is crucial for bacterial colonization of lymph nodes during systemic infection.

Area of Science:

  • Microbiology
  • Bacterial Pathogenesis
  • Molecular Biology

Background:

  • Yersinia enterocolitica is a significant enteric pathogen.
  • It can cause systemic infections, particularly in a murine model.
  • Understanding virulence factors is key to combating bacterial diseases.

Purpose of the Study:

  • To identify novel proteins involved in Yersinia enterocolitica systemic disease.
  • To characterize the role of the newly identified protein, SfpA, in bacterial pathogenesis.
  • To investigate the function and conservation of SfpA in pathogenic bacteria.

Main Methods:

  • Genetic analysis of Yersinia enterocolitica strains, including a DeltasfpA mutant.
  • Bacterial colonization assays in a murine model, focusing on mesenteric lymph nodes.
  • Bioinformatic analysis to predict protein function.
  • Functional studies to confirm the role of SfpA.

Main Results:

  • A novel protein, systemic factor protein A (SfpA), was identified in Yersinia enterocolitica.
  • A DeltasfpA mutant showed significant defects in mesenteric lymph node colonization.
  • Bioinformatic and functional data suggest SfpA functions as a porin.
  • SfpA is conserved in other pathogenic bacterial species.

Conclusions:

  • Systemic factor protein A (SfpA) plays a critical role in the systemic infection mechanism of Yersinia enterocolitica.
  • SfpA is essential for bacterial colonization of host tissues, specifically mesenteric lymph nodes.
  • The identification of SfpA as a porin provides insights into its mechanism of action and potential as a therapeutic target.

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