Composition, structure and function of the Helicobacter pylori cag pathogenicity island encoded type IV secretion
Steffen Backert1, Nicole Tegtmeyer1, Wolfgang Fischer2
1Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen-Nuremberg, Staudtstr. 5, D-91058 Erlangen, Germany.
Future Microbiology
|June 11, 2015
Summary
Helicobacter pylori uses a type IV secretion system (T4SS) to inject the CagA oncoprotein into gastric cells, driving disease. Pilus assembly and function are influenced by metal ions and protein interactions.
Area of Science:
- Microbiology
- Cell Biology
- Pathogenesis
Background:
- Gram-negative pathogens utilize type IV secretion systems (T4SS) to deliver virulence factors into host cells.
- The gastric pathogen Helicobacter pylori relies heavily on its cag pathogenicity island-encoded T4SS for disease progression.
Purpose of the Study:
- To discuss recent advancements in understanding the structure, assembly, and function of the Helicobacter pylori T4SS.
- To highlight the role of T4SS interactions in host cell signaling and pathogenesis.
Main Methods:
- Analysis of crystal structures of T4SS proteins.
- Investigation of pilus formation modulation by iron and zinc availability.
- Review of protein-protein interactions and pilus-associated factors.
Main Results:
- Six T4SS protein crystal structures have been elucidated.
- Pilus assembly is modulated by iron and zinc.
- T4SS interactions are critical for CagA delivery and host signaling deregulation.
Conclusions:
- The T4SS is a key virulence factor for Helicobacter pylori.
- Understanding T4SS mechanisms provides insights into bacterial pathogenesis and host-pathogen interactions.
Keywords:
CagACagLCagYEGF receptorGTPaseHelicobacter pyloriMARK2/PAR1b kinaseT4SSVirB proteinsc-MetcagPAIcortactingastric diseaseintegrinsignalingtype IV secretiontyrosine kinasesβ-cateninMore Related Videos
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