Calum H. G. Johnston

Great talk from @nfrk92.bsky.social (from the TacC lab) at the CBI today, telling us about the mechanisms behind early expression of leading strand genes during conjugation. Cool work!

#microsky
Massive update of preprint with @polardlab.bsky.social!
Bacteria have evolved two systems to recombine extracellular DNA
www.biorxiv.org/content/10.1...
Kudos to lead authors Léo Hardy, Violette Morales and Clothilde Rousseau, and to outstanding Dalia's lab and @epcrocha.bsky.social
🧵⬇️

A toxin/antitoxin system targeting the replication sliding-clamp induces competence in Streptococcus pneumoniae Author summary The environment in which bacteria live puts them under a great deal of stress, forcing them to adapt constantly, either temporarily or permanently. Streptococcus pneumoniae, a pathogeni...

Delighted to share a new paper from our lab, a study led by Mathieu Bergé looking at how an endogenous toxin targets replication to induce competence in the pneumococcus. dx.plos.org/10.1371/jour...

Rescuing the bacterial replisome at a nick requires recombinational repair and helicase reloading - Nature Communications DNA damage can lead to cell death. Here, the authors show that a simple cut on either strand of DNA can inactivate bacterial chromosome replication. Surprisingly, only a core set of recombination prot...

A cool genetic system to study site-pecific replication fork collapse and repair from the brilliant @winterhalterlab.bsky.social

www.nature.com/articles/s41...

New pub. from the lab !

We discovered that potato tubers exert intense selective pressure during Dickeya solani infection, driving the rapid emergence of mutations in the sRNA ArcZ. These mutations lead to the appearance of "social cheaters" that sweep through the pop. in as few as 30 generations.

UK to rejoin EU’s Erasmus student exchange programme Exclusive: British students will be able to participate in EU-wide scheme from January 2027, sources say

Great news! 🎊

www.theguardian.com/world/2025/d...

Le CNRS s’émancipe du Web of Science À partir du 1er janvier 2026, le CNRS coupera l’accès à l’une des plus importantes bases bibliométriques commerciales : le

Le 1er janvier 2026, le CNRS coupera l’accès au Web of Science, Core Collection et Journal Citation Reports. Une nouvelle étape de sa politique en faveur de la science ouverte pour promouvoir des alternatives ouvertes, transparentes et responsables.

Cool work from Heath Murray's lab where they use Cas9 nickase to study how ssDNA breaks are repaired in Bacillus subtilis #MicroSky www.nature.com/articles/s41...

New paper alert 🚨
I am super happy about it, for many reasons!
👥 It was a great collaborative project with Calum @chgjohnston.bsky.social and J. Pablo Radicella, designed a long time ago (in the pre-AlphaFold era - can you imagine?) together with @polardlab.bsky.social and @raphguerois.bsky.social

Thanks Eric! 🙂

Thanks Xavier! :)

Congratulations, really nice work!

A tripartite protein complex promotes DNA transport during natural transformation in Firmicutes | PNAS Natural genetic transformation is a conserved mechanism of bacterial horizontal gene transfer, which is directed entirely by the recipient cell and...

Pleased to share our recent article in PNAS - a collaboration with @jessicaandreani.bsky.social & Pablo Radicella, with important roles played by many members of each team.

A tripartite protein complex promotes DNA transport during natural transformation in Firmicutes www.pnas.org/doi/10.1073/...

Thanks for the kind words Rémi! :)

Come and work with me and @ariannebabina.bsky.social on #Streptomyces evolution and antibiotic production

Origins of a tangled bank: Adaptation and evolution in antibiotic-producing Streptomyces

www.gla.ac.uk/postgraduate...

please repost

New paper from our lab up on Biorxiv, showing how a toxin targets replication to induce competence. 👇

Offre de thèse disponible dans notre équipe au @mmsb-lyon.bsky.social
Si vous êtes étudiant(e) en Master 2 et intéressé(e) par la génétique bactérienne, microscopie à épifluorescence et biochimie, contactez-nous et postulez à l'offre!
Dossier pour le 13/06
Concours école doctorale E2M2: 8 et 9/07.

For those who are interested in all things 'transformation', here is a link to registration for the 6th edition of the Zoom on Griffith's Legacy, the 4th and 5th June 2025.

griffiths2025.sciencesconf.org

It has been fun co-organising this with Luisa Hiller. We hope to see you there!

A tripartite protein complex promotes DNA transport during natural transformation in firmicutes. Natural genetic transformation is a conserved mechanism of bacterial horizontal gene transfer, which is directed entirely by the recipient cell and facilitates the acquisition of new genetic traits su...

Pleased to share a new preprint - a great collaboration with @jessicaandreani.bsky.social and the Guerois lab at I2BC, and the Radicella lab at the CEA. Using stuctural modelling, we reveal & validate a 3 protein complex involved in DNA import during transformation.

www.biorxiv.org/content/10.1...

Let's start the Bsky adventure with a job post. Still about two weeks to apply to this postdoc position on "Molecular and Structural Biology of Membrane Biogenesis" in the labs @raffaeleieva.bsky.social ky.social and @fronzeslab.bsky.social slab.bsky.social in beautiful south-west of France!

Competence induction of homologous recombination genes protects pneumococcal cells from genotoxic stress | mBio Homologous recombination (HR) is a mechanism of DNA strand exchange important for both the maintenance and plasticity of bacterial genomes. Bacterial HR is driven by the recombinase RecA along with ma...

Really proud of our new paper, my first as last author. We explored the importance of homologous recombination genes in transformation and genotoxic stress tolerance during competence. Give it a read/like! 🙂

journals.asm.org/doi/10.1128/...