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A sigma28-regulated nonflagella gene contributes to virulence of Campylobacter jejuni 81-176

Scarlett Goon1, Cheryl P Ewing, Maria Lorenzo

  • 1Enteric Diseases Dept., Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.

Infection and Immunity
|December 22, 2005
PubMed

Insights

A mutant Campylobacter jejuni lacking Cj0977 showed reduced intestinal cell invasion and disease in ferrets. Cj0977 protein expression requires a basic flagella structure for full function.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Bacterial Pathogenesis

Background:

  • Campylobacter jejuni is a leading cause of bacterial gastroenteritis worldwide.
  • Understanding the virulence factors of C. jejuni is crucial for developing effective treatments and prevention strategies.

Purpose of the Study:

  • To investigate the role of the Cj0977 protein in the pathogenesis of Campylobacter jejuni.
  • To determine the relationship between Cj0977 expression and flagellar structure.

Main Methods:

  • Construction and characterization of a Cj0977 deletion mutant of Campylobacter jejuni 81-176.
  • In vitro invasion assays using intestinal epithelial cells.
  • In vivo virulence studies in a ferret diarrheal disease model.

Main Results:

  • The Cj0977 mutant exhibited full motility but a >3 log reduction in intestinal epithelial cell invasion compared to the wild-type parent strain.
  • The mutant strain was significantly attenuated in the ferret diarrheal disease model.
  • Expression of the Cj0977 protein was found to be dependent on the presence of a minimal flagellar structure.

Conclusions:

  • Cj0977 is a significant virulence factor for Campylobacter jejuni, contributing to intestinal cell invasion and disease development.
  • The function of Cj0977 is linked to flagellar assembly, suggesting a role in host-pathogen interactions at the epithelial surface.

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