I'm thrilled this story on accessory PDFs is joined by two companion studies!

🧬 Julie Chen, Paul Blainey and Martin Polz → doi.org/10.1101/2025...

🧬 Alexander Rill, Eva Huber, Helge Bode → Coming soon!

Congrats to all the authors! 🎉🧬

5/5

This reveals a cryptic resistance reservoir within the bacterial mobilome 🧪🦠

PDF-targeting antibiotics face a serious challenge 🚨:
Resistance may not only emerge,
but is already encoded, mobile, and ready to spread!
4/5

Looking at mobile accessory PDF, we identified a highly recombinant integron cassette from Pseudoxanthomonas, encoding an active PDF 💥
When expressed under a native mobile integron promoter in V. cholerae, it confers high-level resistance to PDF inhibitors !
3/5

We uncovered an unexpected pattern:
➡️ ~50% of bacterial genomes encode multiple PDFs
➡️ Accessory PDFs are often found on mobile elements (including plasmids and integron)
➡️ In Vibrio cholerae, the accessory PDF confers resistance to actinonin, the first known PDF inhibitor
2/5

PDFs are conserved and essential enzymes in bacteria.
They deformylate the initiator methionine, a crucial step in protein maturation.
They’ve also been proposed as promising antibiotic targets 💊
But no one had ever looked at the genomic distribution of PDF genes—so we did!
1/5

Thrilled to share my first PhD paper, out of the Mazel lab! @amazeld.bsky.social
We discovered that accessory peptide deformylases (PDFs) are widespread in bacteria and may provide resistance to natural inhibitors, posing a challenge to future antibiotic strategies

doi.org/10.1101/2025...

This reveals a cryptic resistance reservoir within the bacterial mobilome 🧪🦠

PDF-targeting antibiotics face a serious challenge 🚨:
Resistance may not only emerge,
but is already encoded, mobile, and ready to spread!
4/5

Looking at mobile accessory PDF, we identified a highly recombinant integron cassette from Pseudoxanthomonas, encoding an active PDF 💥
When expressed under a native mobile integron promoter in V. cholerae, it confers high-level resistance to PDF inhibitors !
3/5

We uncovered an unexpected pattern:
➡️ ~50% of bacterial genomes encode multiple PDFs
➡️ Accessory PDFs are often found on mobile elements (including plasmids and integron)
➡️ In Vibrio cholerae, the accessory PDF confers resistance to actinonin, the first known PDF inhibitor
2/5

PDFs are conserved and essential enzymes in bacteria.
They deformylate the initiator methionine, a crucial step in protein maturation.
They’ve also been proposed as promising antibiotic targets 💊
But no one had ever looked at the genomic distribution of PDF genes—so we did!
1/5

First preprint from my PhD is now online! We show that deep learning can recognise modes of action of antibiotics directly from brightfield images of bacteria. 🦠

Out today @ Science: TIR signaling activates caspase-like immunity in bacteria

We report a new immune signaling molecule: N7-cADPR. Produced by phage-induced TIRs and activates a defensive bacterial caspase

Congrats Francois Rousset, Ilya Osterman and coauthors!

www.science.org/doi/10.1126/...

New preprint from our Lesterlin Lab! Yannick Baffert and @nfrk92.bsky.social, in collaboration with @macerwan.bsky.social and @val-meve.bsky.social, shed light on the molecular mechanisms driving pOXA-48 plasmid maintenance and transfer. We reveal novel TA system, regulators, and T4SS components!

🚨 New preprint! We know that plasmids are associated with very variable fitness costs in their different bacterial hosts. But, what is the contribution of each of the plasmid-genes in these host-specific effects? Study led by @jorgesastred.bsky.social, @sanmillan.bsky.social and myself! 1/14

Welcome to the official Bluesky page of the Institut Pasteur!

🔬 Explore with us the frontiers of biomedical research

🧪 Follow us to uncover groundbreaking discoveries

💡 Share knowledge for global health

🌍 Join a community passionate about progress and open science.

www.nature.com/articles/s41...
New paper out!!

👋 Hi antiphage defense community, we are soon releasing an update of DefenseFinder.

We are doing our best to include all the great discoveries from the community, but with so much going on we might miss things.

Please answer wt preprints/papers with new systems or mail/git them to us. 🙏

🚨New review🚨

Evolution and ecology of anti-defence systems in phages and plasmids

Link: www.cell.com/current-biol...

1/ 🔬 Our work, "Dynamic transitions of initiator binding coordinate the replication of the two chromosomes in Vibrio cholerae", is now published in Nature Communications.
Here's a thread on how we think Chr1 and Chr2 replication is coordinated in Vibrio. 🧵

Link : www.nature.com/articles/s41...

Our paper on 🦠queuosine 34 modification of tRNA tyrosine and antibiotic response is finally out in its final form in @eLife ... and quite different from the preprint version. Many thanks to reviewers, editors and kudos to all authors🙏 elifesciences.org/articles/96317