The pathogenic potential of Helicobacter pullorum: possible role for the type VI secretion system
Andrea Sirianni1, Nadeem O Kaakoush, Mark J Raftery
1School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia.
Helicobacter
|October 17, 2012
Summary
Helicobacter pullorum adheres to and invades human intestinal cells, secreting potential virulence factors. This study investigates its pathogenic mechanisms in vitro, revealing key interactions and secreted proteins.
Area of Science:
- Microbiology
- Pathogen Research
- Cell Biology
Background:
- Helicobacter pullorum is implicated in avian and human hepatobiliary and gastrointestinal diseases.
- The pathogenic potential of H. pullorum NCTC 12826 requires further investigation.
Purpose of the Study:
- To investigate the pathogenic potential of Helicobacter pullorum NCTC 12826.
- To characterize the adherence, invasion, and secretome of H. pullorum in vitro.
Main Methods:
- Utilized adherence and gentamicin protection assays to quantify bacterial interaction with Caco-2 cells.
- Employed scanning electron microscopy for visualizing adherence and invasion mechanisms.
- Applied proteomics and mass spectrometry to characterize the H. pullorum secretome.
Main Results:
- H. pullorum demonstrated adherence (1.98 ± 0.16%) and invasion (0.25 ± 0.02%) of Caco-2 intestinal epithelial cells.
- Scanning electron microscopy revealed flagellum-microvillus interaction and membrane ruffling during invasion.
- Identified 137 proteins, including 33 predicted secreted proteins, with six putative virulence factors like flagellin and Hcp.
Conclusions:
- Helicobacter pullorum possesses the capability to adhere to and invade human intestinal cells.
- Secreted factors identified in this study may contribute to the pathogenicity of H. pullorum.
- Structural analysis suggests the type VI secretion system may interact with host endocytic vesicles.
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