Four Chromosomal Type IV Secretion Systems in Helicobacter pylori: Composition, Structure and Function.
Wolfgang Fischer1, Nicole Tegtmeyer2, Kerstin Stingl3
1Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie, Medizinische Fakultät, LMU München, Munich, Germany.
Frontiers in Microbiology
|August 6, 2020
Summary
Helicobacter pylori utilizes four distinct type IV secretion systems (T4SSs) for DNA exchange and effector delivery, driving its genetic diversity and adaptation. These T4SSs are crucial for H. pylori
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Helicobacter pylori is a pathogenic bacterium responsible for peptic ulcers and gastric cancer.
- H. pylori exhibits significant genetic diversity, influenced by acquired type IV secretion systems (T4SSs).
- T4SSs are versatile molecular machines involved in DNA transfer and effector secretion.
Purpose of the Study:
- To review the current knowledge on the four T4SSs in H. pylori.
- To elucidate the mechanisms and functions of these T4SSs.
- To understand the role of T4SSs in H. pylori adaptation.
Main Methods:
- Review of existing literature on H. pylori T4SSs.
- Analysis of the genetic organization and functional domains of T4SSs.
- Comparison of T4SS functions in DNA transfer and effector secretion.
Main Results:
- H. pylori possesses four T4SSs: Cag T4SS, ComB, Tfs3, and Tfs4.
- Cag T4SS delivers CagA and other effectors; ComB imports extracellular DNA.
- Tfs3 and Tfs4 are implicated in DNA conjugation and effector secretion (CtkA).
Conclusions:
- The four T4SSs contribute significantly to H. pylori's genetic exchange and diversity.
- T4SSs play a critical role in H. pylori's adaptation to the human stomach environment.
- Understanding T4SSs is key to comprehending H. pylori pathogenesis and evolution.
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