Evidence map›Paper›PMID 35239059›Full record

ArticleCurrent microbiology2022

Unique TLR9 Activation by Helicobacter pylori Depends on the cag T4SS, But Not on VirD2 Relaxases or VirD4 Coupling Proteins.

Nicole Tegtmeyer, Bodo Linz, Yoshio Yamaoka, Steffen Backert

Open access · hybridAbstract read
In one paragraph

Article in Current microbiology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
7citing papers in PubMed, 1 pooled it
3.1field-weighted citation impact, top 9% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

7 citing papers in PubMed, 1 synthesis or guideline pooled it, 16 citations in OpenAlex.

  1. Pooled it
  2. Article
  3. CopGBiology · 2024
    Article
  4. The immunopathogenesis ofFrontiers in microbiology · 2024
    Review
  5. Pathogenomics of Helicobacter pylori.Current topics in microbiology and immunology · 2023
    Review
  6. Immune Biology and Persistence of Helicobacter pylori in Gastric Diseases.Current topics in microbiology and immunology · 2023
    Article
  7. RecombinantAntibiotics (Basel, Switzerland) · 2022
    Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors at 2 institutions in 2 countries.

Nicole TegtmeyerDepartment of Biology, Chair of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058, Erlangen, Germany.
Bodo LinzDepartment of Biology, Chair of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058, Erlangen, Germany.
Yoshio YamaokaDepartment of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Japan.
Steffen BackertDepartment of Biology, Chair of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058, Erlangen, Germany. Steffen.Backert@fau.de.
Friedrich-Alexander-Universität Erlangen-Nürnberg · DEOita University · JP

Funding

Deutsche Forschungsgemeinschaft TE776/3 1
6 · The paper itself

Abstract

The genomes of the gastric bacterial pathogen Helicobacter pylori harbor multiple type-IV secretion systems (T4SSs). Here we analyzed components of three T4SSs, the cytotoxin-associated genes (cag) T4SS, TFS3 and TFS4. The cag T4SS delivers the effector protein CagA and the LPS-metabolite ADP-heptose into gastric epithelial cells, which plays a pivotal role in chronic infection and development of gastric disease. In addition, the cag T4SS was reported to facilitate conjugative transport of chromosomal bacterial DNA into the host cell cytoplasm, where injected DNA activates intracellular toll-like receptor 9 (TLR9) and triggers anti-inflammatory signaling. Canonical DNA-delivering T4SSs in a variety of bacteria are composed of 11 VirB proteins (VirB1-11) which assemble and engage VirD2 relaxase and VirD4 coupling proteins that mediate DNA processing and guiding of the covalently bound DNA through the T4SS channel. Nevertheless, the role of the latter components in H. pylori is unclear. Here, we utilized isogenic knockout mutants of various virB (virB9 and virB10, corresponding to cagX and cagY), virD2 (rlx1 and rlx2), virD4 (cag5, traG1/2) and xerD recombinase genes in H. pylori laboratory strain P12 and studied their role in TLR9 activation by reporter assays. While inactivation of the structural cag T4SS genes cagX and cagY abolished TLR9 activation, the deletion of rlx1, rlx2, cag5, traG or xerD genes had no effect. The latter mutants activated TLR9 similar to wild-type bacteria, suggesting the presence of a unique non-canonical T4SS-dependent mechanism of TLR9 stimulation by H. pylori that is not mediated by VirD2, VirD4 and XerD proteins. These findings were confirmed by the analysis of TLR9 activation by H. pylori strains of worldwide origin that possess different sets of T4SS genes. The exact mechanism of TLR9 activation should be explored in future studies.

Indexed as

Helicobacter InfectionsHelicobacter pyloriAntigens, BacterialBacterial ProteinsCytotoxinsHumansToll-Like Receptor 9Type IV Secretion SystemsAntigens, BacterialBacterial ProteinsCytotoxinsTLR9 protein, humanToll-Like Receptor 9Type IV Secretion Systems

Identifiers

PMID35239059
PMCPMC8894178
OpenAlexW4214819155

What OpenQuestion holds

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LicenceCC BY
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.