Stephan Gruber

Prashant Singh in the lab of Tina Iverson at Vanderbilt published this image of the bacterial 🦠flagellar motor, a detailed molecular model made possibly by CryoEM 🔬.

The similarity to mechanical motors are strong enough we can use terms like stator, rotor, rod & gearing to describe it.

🌍Open call: Junior Group Leader positions!

Join a world-class biomedical research institute at the heart of the Vienna BioCenter, where curiosity drives discovery.

Lead your own lab, pursue bold ideas, and shape the future of science at the IMP: www.imp.ac.at/career/open-...

What Rosalind Franklin truly contributed to the discovery of DNA’s structure Franklin was no victim in how the DNA double helix was solved. An overlooked letter and an unpublished news article, both written in 1953, reveal that she was an equal player.

What Rosalind Franklin truly contributed to the discovery of DNA’s structure. A really informative article, perfect for a weekend coffee read. www.nature.com/articles/d41...

The bacterial condensin MukBEF compacts DNA into a repetitive, stable structure - PubMed Condensins are conserved proteins containing SMC (structural maintenance of chromosomes) moieties that organize and compact chromosomes in an unknown mechanism essential for faithful chromosome partitioning. We show that MukBEF, the condensin in Escherichia coli, cooperatively compacts a single DNA …

This paper was retracted (by the authors) a long time ago:
pubmed.ncbi.nlm.nih.gov/15178751/

However, I cannot find a retraction notice on the DOI page:
www.science.org/doi/10.1126/...

Is this standard practice, or an oversight?
@science.org

I was not aware that Walther Flemming did (some of) his groundbreaking work in Kiel

Very nice Preview by @bramkamplab.bsky.social on the SMC DNA loading paper by our @roisnehamelinf.bsky.social

"Weaving the loops of life: DNA loading by loop-extrusion machines in plasmid defense and genome organization"

Molecular Cell www.cell.com/molecular-ce...

Congrats!

Thank you, Aude!

Could you add us too please?

University of Lausanne
www.unil.ch/gruberlab

Thank you!

All the world’s a phage | PNAS A renewed interest in bacteriophages has emerged from the explosive discovery of the complex pan-immune bacterial defense system and a revival of t...

#microsky #phagesky
Mycobacterium #phage review by Graham Hatfull covering the state of the art

www.pnas.org/doi/10.1073/...

📢 Open Call! The Max Perutz Labs invite applications for a Full Professorship in Integrative Structure Biology with a focus on in situ structural biology using cryo-electron tomography (cryo-ET) and related methods. More details ➡️ tinyurl.com/brswbymu

Or just skip the PAE plots, the structures, and all that biochemical “validation”… and go straight to the only true testing by genetics 🤠

Really cool!
But Bluesky has flipped your picture over - it now shows positively supercoiled left-handed DNA :-(.

www.nature.com/articles/d41...

who would have thought! phage N15 TelN telomerase has more than one job!
(and no, it's not 'moonlighting')
great work from the gruber lab 👏
#MicroSky + #PhageSky

E. coli bacteriophage N15 suppresses Mre11-Rad50-mediated end degradation of its linear genome via a telomere-resolution-independent function of its telomere resolvase TelN
#RefereedPreprint c/o @reviewcommons.org by @gruberlab.bsky.social
www.embopress.org/doi/full/10....

This was a fun collaboration between Ophélie & the @seegerlab.bsky.social using sybody libraries to target the SMC complex in living bacteria. With a suprising finding: the 14 isolated sybodies bind to the middle of the SMC coiled coil rather than the more conserved ATPase heads.

Single Domain Antibody Inhibitors Target the Coiled Coil Arms of the Bacillus subtilis SMC complex https://www.biorxiv.org/content/10.1101/2025.10.16.682983v1

Mechanism of DNA entrapment by a loop-extruding Wadjet SMC motor Wadjet is an SMC-based prokaryotic defense system that eliminates plasmid DNA. Roisné-Hamelin et al. present structures capturing key steps of its DNA-loading mechanism. This work reveals how Wadjet topologically entraps DNA by SMC dimer rotation around DNA and defines the starting point of loop extrusion by the SMC motor.

Online Now: Mechanism of DNA entrapment by a loop-extruding Wadjet SMC motor Online now:

Structure and activation mechanism of a Lamassu phage and plasmid defense system Nature Structural & Molecular Biology, Published online: 14 October 2025; doi:10.1038/s41594-025-01677-4Li et al. show that a Lamassu defense system protects bacteria from phage infection by activating a lethal tetrameric DNA-cutting enzyme. In the absence of phages, a protein clamp holds the enzyme as an inactive monomer, preventing self-damage.

New online: Structure and activation mechanism of a Lamassu phage and plasmid defense system

Hijacking a bacterial ABC transporter for genetic code expansion - Nature Bacterial ATP-binding cassette (ABC) transporters can be utilized and engineered to transport non-canonical amino acids into Escherichia coli for highly efficient synthesis of proteins with novel func...

🚨Our paper is out! 🥳
Hijacking a bacterial ABC transporter for efficient genetic code expansion.
Many congrats to everyone involved - a multi-year effort led by @taruniype.bsky.social @maxfottner.bsky.social
www.nature.com/articles/s41...

it all started years ago with a failed experiment
🧵👇 1/9

And also the bacterial telomere protection paper by Maya, Nicolas, & Ania is out:

doi.org/10.1038/s443...

Great experience with @reviewcommons.org
& @embojournal.org

Feels just right to have the manuscript reviewed without having to target a specific journal from the start.

You should at least give it a go. you won't be disappointed. ;-)

here is a free link (view-only): rdcu.be/eKWbz

Happy that the final version of our Lamassu work @yli18smc.bsky.social is now out:

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

Thanks again to our awesome collaborators @mblokesch.bsky.social and David and co and Mark Szczelkun and @steven-shaw.bsky.social and the DCI Lausanne @fbm-unil.bsky.social

We are pleased to highlight this article published by @gruberlab.bsky.social. At DCI, F. Roisne Hamelin and collaborators used electron microscopy — and in particular our streptavidin affinity grids — to reveal the mechanism by which Wadjet binds to the plasmid to initiate loop extrusion.

Thank you, Biswajit!

As always, bacteria light the path of discovery.

Thanks!

We use the symbol for Wadjet, one of the goddesses personifying the Eye of Ra. Not sure this is entirely correct. I hope she does not mind 😄

Thank you, Luuk!