Four Chromosomal Type IV Secretion Systems in Helicobacter pylori: Composition, Structure and Function

Bacterial type IV secretion systems (T4SS) perform two fundamental functions related to pathogenesis: the delivery of effector molecules to eukaryotic target cells, and genetic exchange. Two T4SSs have been identified in Burkholderia cenocepacia K56-2, a representative of the ET12 lineage of the B. cepacia complex (Bcc). The plant tissue watersoaking (Ptw) T4SS encoded on a resident 92 kb plasmid is a chimera composed of VirB/D4 and F-specific subunits, and is responsible for the translocation of effector(s) that have been linked to the Ptw phenotype. The bc-VirB/D4 system located on chromosome II displays homology to the VirB/D4 T4SS of Agrobacterium tumefaciens. In contrast to the Ptw T4SS, the bc-VirB/D4 T4SS was found to be dispensable for Ptw effector(s) secretion, but was found to be involved in plasmid mobilization. The fertility inhibitor Osa did not affect the secretion of Ptw effector(s) via the Ptw system, but did disrupt the mobilization of a RSF1010 derivative plasmid.

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The structural biology of type IV secretion systems

Nature Reviews Microbiology ◽

10.1038/nrmicro2218 ◽

2009 ◽

Vol 7 (10) ◽

pp. 703-714 ◽

Cited By ~ 231

Author(s):

Rémi Fronzes ◽

Peter J. Christie ◽

Gabriel Waksman

Keyword(s):

Structural Biology ◽

Type Iv Secretion ◽

Secretion Systems ◽

Type Iv ◽

Type Iv Secretion Systems

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Export von Gefahrgut: Helicobacter pylori und sein CagA-Protein

BIOspektrum ◽

10.1007/s12268-020-1454-7 ◽

2020 ◽

Vol 26 (6) ◽

pp. 597-599

Author(s):

Clara Lettl ◽

Wolfgang Fischer

Keyword(s):

Helicobacter Pylori ◽

Pathogenic Bacteria ◽

Type Iv Secretion ◽

Host Cells ◽

Bacterial Protein ◽

Secretion Systems ◽

Unusual Structure ◽

Type Iv ◽

Single Protein ◽

Protein Transporters

Abstract Pathogenic bacteria often utilize type IV secretion systems to interact with host cells and to modify their microenvironment in a favourable way. The human pathogen Helicobacter pylori produces such a system to inject only a single protein, CagA, into gastric cells, but this injection represents a major risk factor for gastric cancer development. Here, we discuss the unusual structure of the Cag secretion nanomachine and other features that make it unique among bacterial protein transporters.

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T4SP Database 2.0: An Improved Database for Type IV Secretion Systems in Bacterial Genomes with New Online Analysis Tools

Computational and Mathematical Methods in Medicine ◽

10.1155/2016/9415459 ◽

2016 ◽

Vol 2016 ◽

pp. 1-4 ◽

Cited By ~ 3

Author(s):

Na Han ◽

Weiwen Yu ◽

Yujun Qiang ◽

Wen Zhang

Keyword(s):

Recipient Cell ◽

Bacterial Species ◽

Genetic Material ◽

Type Iv Secretion ◽

Bacterial Strains ◽

Secretion Systems ◽

Bacterial Genomes ◽

Type Iv ◽

Type Iv Secretion Systems ◽

User Friendly

Type IV secretion system (T4SS) can mediate the passage of macromolecules across cellular membranes and is essential for virulent and genetic material exchange among bacterial species. The Type IV Secretion Project 2.0 (T4SP 2.0) database is an improved and extended version of the platform released in 2013 aimed at assisting with the detection of Type IV secretion systems (T4SS) in bacterial genomes. This advanced version provides users with web server tools for detecting the existence and variations of T4SS genes online. The new interface for the genome browser provides a user-friendly access to the most complete and accurate resource of T4SS gene information (e.g., gene number, name, type, position, sequence, related articles, and quick links to other webs). Currently, this online database includes T4SS information of 5239 bacterial strains.Conclusions. T4SS is one of the most versatile secretion systems necessary for the virulence and survival of bacteria and the secretion of protein and/or DNA substrates from a donor to a recipient cell. This database on virB/D genes of the T4SS system will help scientists worldwide to improve their knowledge on secretion systems and also identify potential pathogenic mechanisms of various microbial species.

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