Structures of the QatBC complex from Angela Gao and Doug Wassarman in our group reveal an evolutionary link between QatABCD and Type IV CBASS and a role for protein deazguanylation in diverse anti-phage defense systems

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

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

Those amazing #phages 🦠 figured out 5mC chemistry before we did:
📄 Out today in @MolecularCell we describe a 5mC-selective #deaminase family in environmental phage genomes with broad applications for #5base #sequencing
#epigenetics #DNAmethylation #genomics #NGS 🧬🧪
www.cell.com/molecular-ce...

I am so excited to share our new findings with you! We provide the structural evidence for a direct protein-to-DNA information pathway, showing how a bacterial enzyme 'reads' its own structure to 'write' DNA. www.science.org/doi/10.1126/...

A bacterial CARD–NLR-like immune system controls the release of gene transfer agents - Nature Microbiology An immunity-like system functions as a lysis control hub to promote gene transfer agent particle release from host bacterial cells, suggesting that bacterial immune systems may be co-opted to promote ...

Delighted to share our latest work on gene transfer agents (GTAs). We found a lysis control hub which allows GTAs to escape their bacterial host cells and transfer DNA 🧬 between bacteria. Thanks to @tunglejic.bsky.social, all co-authors, and our amazing collaborators!
www.nature.com/articles/s41...

Diversity-generating retroelements for programmable targeted hypermutagenesis - Nature Biotechnology Diversity-generating retroelements are engineered for directed evolution in E.coli.

🔈Paper out! We turned the most fascinating phage host-switch mechanism, diversity-generating retroelements, into a programmable mutagenesis tool, DGRec. You can perform targeted hypermutation of any 50-200bp sequence directly in vivo in E. coli www.nature.com/articles/s41...

Over two billion years, a fierce battle has raged between bacteria and the viruses that infect them. The resulting evolution has shaped the way our bodies fight disease today. @vcallier.bsky.social reports: www.quantamagazine.org/the-ancient-...

Thank you to @vcallier.bsky.social and Quanta Magazine for highlighting our lab along with the incredible research from @soreklab.bsky.social @audeber.bsky.social @aaronwhiteley.bsky.social @benmorehouse.bsky.social @teralevin.bsky.social @algao.bsky.social Eugene Koonin, L. Aravind and others!

Excited to share our new paper out today in @science.org 🎉

We show that HGT via natural competence drives diversification of chromosomal integrons in V. cholerae 🤩

Below a 🧵 on key findings incl. background on natural competence in V. cholerae 1/
#microsky #phagesky
www.science.org/doi/10.1126/...

2026 Peter Gilgan Canada Gairdner Momentum Award, Karen Maxwell YouTube video by CanadaGairdnerAwards

Congratulations to Karen Maxwell @themaxwelllab.bsky.social on the 2026 Peter Gilgan Canada Gairdner Momentum Award! An amazing selection and leader in the bacterial immunity field!

www.youtube.com/watch?v=u0pg...

Archaeal genes code for GGDEF domain proteins with diguanylate cyclase activity

doi.org/10.32942/X2K...

How diverse is bacterial immunity ?

We report in @science.org how language models allowed us to predict 2.4M antiphage proteins spanning >23K novel potential systems.
👏 @emordret.bsky.social, @alexhv.bsky.social & al doi.org/10.1126/scie...

Explore them here defensefinder.mdmlab.fr/wiki/refseq_...

2.39 million antiphage proteins in 32,000 bacterial genomes!! Congratulations Aude & team!

How do you kill a MRSA superbug armed with 15 different anti-phage defense systems? You make a smarter phage. Check out our latest preprint on overcoming bacterial immunity using defense-guided engineering to build durable therapeutic phage cocktails! Led by Sarah Voss. doi.org/10.64898/202...

Out now–our work on bacterial cGAS-like enzymes making 2′,3′-cGAMP! Read Uday's thread for updates since the preprint including determining our lab's first protein structure and developing a new system to study bacterial STING homologs in phage defense👇

Bacterial 2′,3′-cGAMP activates a SAVED effector to form membrane-disrupting filaments and restrict phage replication Tak et al. discover that bacteria use 2′,3′-cGAMP, the same signaling molecule employed by mammalian cGAS-STING, for phage defense. In response to phage, 2′,3′-cGAMP activates filament formation of Ca...

Happy to share the final version of my postdoc work on bacterial CBASS immunity with @aaronwhiteley.bsky.social published in @cp-cellhostmicrobe.bsky.social

www.cell.com/cell-host-mi...

The 2026 Schmidt Science Fellows Will Break Down Barriers And Advance Discovery • Schmidt Science Fellows The 2026 Schmidt Science Fellows will pursue an ambitious “interdisciplinary pivot” for their postdoctoral research in a new field of study from their PhD to tackle challenges from microplastics to su...

Congratulations to @joelmjtan.bsky.social , @erezyirmiya.bsky.social , and the other 2026 Schmidt Science Fellows!

schmidtsciencefellows.org/news/the-202...

gsas.harvard.edu/news/three-h...

Little is known about bacterial immunity to RNA phages. The @jenshoer.bsky.social lab discovers ApeA recognition of phage RNA stem loops. With RNA viruses dominating emerging pathogens in humans, a very exciting area of comparison in host antiviral immunity!

www.biorxiv.org/content/10.6...

How can we study the function of nucleotide-based #SecondMessengers?

@oliveiramann.bsky.social presented her group's exciting findings in this field at #Biochemistry2026. She e.g. presented the #cryoEM structure of OAS2, which has key #antiviral functions.

linkinghub.elsevier.com/retrieve/pii...

A complete set of canonical nucleobases in the carbonaceous asteroid (162173) Ryugu - Nature Astronomy Samples returned from the asteroid Ryugu contain all five canonical nucleobases (A, G, C, T and U). Their presence in Ryugu and Bennu supports the hypothesis that carbonaceous asteroids contributed to the prebiotic chemical inventory of early Earth.

Samples returned from the asteroid Ryugu contain all five canonical nucleobases (A, G, C, T, U). Their presence in Ryugu and Bennu supports the hypothesis that carbonaceous asteroids contributed to the prebiotic chemical inventory of early Earth. http://dlvr.it/TRWtVp ☄️

Our lab is excited to share unpublished research on phage defense at the upcoming 2026 Symposium on the Immune System of Bacteria!

Today is the last day for abstract submissions: sisb2026.rockefeller.edu

Thank you to Marraffini @naamaaviram.bsky.social Seed @jbdsf.bsky.social labs for organizing!

New preprint: Cyclic tri-adenylate signalling by a Panoptes anti-phage guard system with a CARF-TM effector. Great work led by Sabine Grüschow
www.biorxiv.org/content/10.6...

Brianna is an incredible scientist and mentor. See below for a great opportunity for anyone seeking an immersive science experience before starting graduate school.

Our work on bacterial Schlafens in phage defense is out today @natmicrobiol.nature.com!

Check out the final version here:
rdcu.be/e7Bmz

We are looking for postdocs and students to expand our team! Official postings are coming soon.

Please reach out if you're interested!
#phage #phagesky #microsky

🚨Preprint! Happy to share the research from my PhD “Genome delivery of a contractile tailed phage and its superinfection exclusion mechanism”. We use cryoEM to study the genome ejection of the phage T4, revealing how the tape measure protein regulates the process.
www.biorxiv.org/content/10.6...

Deltaviruses spread through a viral Trojan Horse Hepatitis D-like satellite viruses, known as deltaviruses, have been recently discovered in a wide range of animals. These viruses are thought to expr…

We found a viral Trojan Horse: a virus can hide inside another virus.This one surprised us: deltaviruses don’t just borrow a helper virus. They can travel inside it.
A literal Trojan Horse “virus-in-a-virus” route into cells. 🤯 Kudos to 1st author @viroscope.bsky.social and co-authors !

Check out this new preprint discovering a cool mechanism for activation of the CBASS antiphage system-- proteolytic cleavage by the phage protease! Explains why I couldn't isolate any spontaneous phage mutants that escape CBASS.

Super cool. Can't wait to read in depth 🤓 Congrats Sam & Philip! 🥂

A must-read if you’re interested in bacterial immune system activation

See full details and thread from @hobbslabutah.bsky.social here:

Sam's results build on beautiful findings from many labs including @aaronwhiteley.bsky.social @kevincorbett.bsky.social @soreklab.bsky.social @jbdsf.bsky.social @mfwhite2.bsky.social Chen and Marraffini explaining viral escape mutations and CBASS recognition of late replication and virion assembly

Protease recognition is a dominant trigger of bacterial cGAS (CD-NTase) immune sensing that explains activation of thousands of CBASS defense operons across diverse bacteria (>24% of all known sequences) including major models of immunity like Vibrio DncV, Enterobacter CdnD, and E. coli CdnG