Host-induced spermidine production in motile Pseudomonas aeruginosa triggers phagocytic uptake
- Helmholtz Centre for Infection Research, Germany
Abstract
Exploring the complexity of host-pathogen communication is vital to understand why<br /> microbes persist within a host, while others are cleared. Here, we employed a Dual-sequencing approach to unravel conversational turn-taking of dynamic host-pathogen communications. We demonstrate that upon hitting a host cell, motile Pseudomonas aeruginosa induce a specific gene expression program. This results in the expression of spermidine on the surface, which specifically activates the PIP3-pathway to induce phagocytic uptake into primary or immortalized murine cells. Non-motile bacteria are more immunogenic due to a lower expression of arnT upon host cell contact, but do not produce spermidine and are phagocytosed less. We demonstrate that not only the presence of pathogen inherent molecular patterns induces immune responses, but that bacterial motility is linked to a host-cell induced expression of additional immune modulators. Our results emphasize on the value of integrating microbiological and immunological findings to unravel complex and dynamic host-pathogen interactions.
Data availability
Raw files and reads per gene of the RNA sequencing approaches have been deposited in the NCBI Gene Expression Omnibus (GEO) under the accession number GSE141757.
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Host-induced spermidine production in motile Pseudomonas aeruginosa triggers phagocytic uptakeNCBI Gene Expression Omnibus, GSE141757.
Article and author information
Author details
Funding
ERC Consolidator Grant COMBAT (724290)
- Susanne Häussler
DFG, Germany's Excellence Strategy - EXC 2155 RESIST (390874280)
- Susanne Häussler
SPP (1879)
- Susanne Häussler
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal experiments were performed according to guidelines of the German Law for Animal Protection and with permission of the local ethics committee and the local authority LAVES (Niedersächsisches Landesamt für Verbraucherschutz und Lebensmittelsicherheit). C57BL/6 mice derived from our own breeding.
Copyright
© 2020, Felgner et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Host-induced spermidine production in motile Pseudomonas aeruginosa triggers phagocytic uptake
eLife 9:e55744.
https://doi.org/10.7554/eLife.55744
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