Aminoglycoside tolerance in Vibrio cholerae engages translational reprogramming associated to queuosine tRNA modification

Tgt is the enzyme modifying the guanine (G) in tRNAs with GUN anticodon to queuosine (Q). tgt is required for optimal growth of Vibrio cholerae in the presence of sub-lethal aminoglycoside concentrations. We further explored here the role of the Q in the efficiency of codon decoding upon tobramycin exposure. We characterized its impact on the overall bacterial proteome, and elucidated the molecular mechanisms underlying the effects of Q modification in antibiotic translational stress response. Using molecular reporters, we showed that Q impacts the efficiency of decoding at tyrosine TAT and TAC codons. Proteomics analyses revealed that the anti-SoxR factor RsxA is better translated in the absence of tgt. RsxA displays a codon bias towards tyrosine TAT and overabundance of RsxA leads to decreased expression of genes belonging to SoxR oxidative stress regulon. We also identified conditions that regulate tgt expression. We propose that regulation of Q modification in response to environmental cues leads to translational reprogramming of genes bearing a biased tyrosine codon usage. In silico analysis further identified candidate genes possibly subject to such translational regulation, among which DNA repair factors. Such transcripts, fitting the definition of modification tunable transcripts, are plausibly central in the bacterial response to antibiotics. Overall design: RiboSeq of three replicates of two Vibrio Cholerae strains (one WT and the other deleted for the tgt gene) in presence or absence of tobramycin, to identify which genes are impacted at the translational level by the antibiotic.

Identifier
Source https://data.blue-cloud.org/search-details?step=~0125CF58C566C5E1FA92458104E9F5AA0A49B1F4863
Metadata Access https://data.blue-cloud.org/api/collections/5CF58C566C5E1FA92458104E9F5AA0A49B1F4863
Provenance
Publisher Blue-Cloud Data Discovery & Access service; ELIXIR-ENA
Publication Year 2025
OpenAccess true
Contact blue-cloud-support(at)maris.nl
Representation
Discipline Marine Science
Temporal Point 2025-01-07T00:00:00Z