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Updated: May 16, 2026
08:13
Overexpressing and Purifying a Toxic Nuclease from Escherichia coli
Published on: August 29, 2025
Host norepinephrine biases codon-dependent virulence translation in EHEC
1Epitranscriptomic and translational responses to antibacterial stress Team, Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, Expression Génétique Microbienne, Institut Pasteur, Paris, France.
Msystems
|May 14, 2026
Summary
The host hormone norepinephrine reprograms bacterial translation by altering tRNA modifications in enterohemorrhagic Escherichia coli (EHEC). This rewiring selectively boosts the expression of virulence genes, impacting bacterial pathogenesis.
Area of Science:
- Microbiology
- Molecular Biology
- Bacterial Pathogenesis
Background:
- Bacterial pathogens utilize host signals to regulate virulence.
- The precise mechanisms by which these signals influence bacterial translation are not fully understood.
Purpose of the Study:
- To investigate how host-derived signals, specifically norepinephrine, affect the translation machinery in enterohemorrhagic Escherichia coli (EHEC).
- To elucidate the role of tRNA epitranscriptomics in mediating bacterial virulence gene expression in response to host cues.
Main Methods:
- Analysis of tRNA epitranscriptome modifications in EHEC exposed to norepinephrine.
- Multi-omic analyses (including transcriptomics and proteomics) to assess changes in gene expression and protein levels.
- Investigation of codon usage bias in virulence gene loci.
Main Results:
- Norepinephrine alters tRNA wobble-position modifications in EHEC.
- This modification shift biases decoding towards A/U-ending codons, matching the codon usage of the locus of enterocyte effacement (LEE).
- Proteome remodeling occurs without significant changes in tRNA abundance, linking tRNA chemistry to virulence.
Conclusions:
- The tRNA epitranscriptome dynamically regulates bacterial virulence in response to host hormones.
- Host hormone sensing is coupled to codon-biased translation, enabling selective expression of bacterial virulence factors.
- This study establishes a novel link between host-pathogen interactions and translational control in bacterial pathogens.
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