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Reposted by Aleksei Agapov

Michael Brockhurst @brockhurstlab.bsky.social · 2d

New preprint!

Ever wondered why only a fraction of genomes encode CRISPR immunity? 🧬 🦠

Turns out CRISPR is rarely beneficial against virulent phages, being most beneficial against those for which resistance mutations are rare!

An epic effort by Rosanna Wright

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

Resistance mutation supply modulates the benefit of CRISPR immunity against virulent phages

Only a fraction of bacterial genomes encode CRISPR-Cas systems but the selective causes of this variation are unexplained. How naturally virulent bacteriophages (phages) select for CRISPR immunity has...

www.biorxiv.org

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Alice Maestri @alicemaestri.bsky.social · 26d

We're looking for a technician at Institut Pasteur for experimental work on satellite-phage-bacteria interactions, working directly with @jmouradesousa.bsky.social and myself in the lab of @epcrocha.bsky.social ! ANR funded.

Link to the job emploi.pasteur.fr/offre-de-emp...
Thx for sharing!

INSTITUT PASTEUR - Technicien de recherche Microbiologie H/F

emploi.pasteur.fr

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Daniel Padfield @padpadpadpad.bsky.social · 22d

I have an MRC-funded PhD project available (www.exeter.ac.uk/study/fundin...) on how warming will change the problem of AMR. Join a small and friendly group (padpadpadpad.netlify.app/about) in (sometimes) sunny Cornwall. 🧪🦠 #microsky

Please share the ad below with anyone who may be interested.

A teal flyer for a PhD opportunity to investigate how warming may change antimicrobial resistance. The project will use experiments on Klebsiella bacteria to answer questions about how temperature affects their response to antibiotics, plasmid transfer, and fitness costs. The research involves microbiology lab work, bioinformatics, and mathematical modeling. The flyer includes contact details for Dr. Daniel Padfield and the logos of the sponsoring institutions.

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Josie Elliott @josie-e.bsky.social · Sep 4

Can CRISPR-Cas systems target any phage? Yes, no, it depends? What does it depend on? The second paper from my PhD came out today in a special issue of Phil Trans B on the ecology and evolution of bacterial immune systems
doi.org/10.1098/rstb...

Phage susceptibility to a minimal, modular synthetic CRISPR-Cas system in Pseudomonas aeruginosa is nutrient dependent | Philosophical Transactions of the Royal Society B: Biological Sciences

CRISPR-Cas systems can provide adaptive, heritable immunity to their prokaryotic hosts against invading genetic material such as phages. It is clear that the importance of acquiring CRISPR-Cas immunit...

doi.org

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Benoit Pons @benoitjpons.bsky.social · Sep 4

How do bacteria choose what type of defences to use against phages? We explored that question in the last paper I worked on as a postdoc at the Uni of Exeter @uniofexeteresi.bsky.social with Stineke van Houte, Stefano Pagliara and Edze Westra (not on Bluesky)
doi.org/10.1098/rstb...

Phage provoke growth delays and SOS response induction despite CRISPR-Cas protection | Philosophical Transactions of the Royal Society B: Biological Sciences

Bacteria evolve resistance against their phage foes with a wide range of resistance strategies whose costs and benefits depend on the level of protection they confer and on the costs for maintainance....

doi.org

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Peter Fineran @peterfineran.bsky.social · Aug 18

Ever wondered why some bacteria have multiple CRISPR-Cas systems? Our new study led by Leah Smith shows how type I CRISPR systems can promote the acquisition and retention of new spacers into a co-occuring type III system. www.sciencedirect.com/science/arti...

Type I CRISPR-Cas immunity primes type III spacer acquisition

CRISPR-Cas systems are diverse, with microbes harboring multiple classes and subtypes. Type I DNA-targeting and type III RNA-targeting systems often c…

www.sciencedirect.com

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Asaf Levy @asaflevylab.bsky.social · Jul 26

Expression level of anti-phage defence systems controls a trade-off between protection range and autoimmunity
By Nitzan Aframian and Avigdor Eldar.
www.nature.com/articles/s41...

Expression level of anti-phage defence systems controls a trade-off between protection range and autoimmunity - Nature Microbiology

The authors examine several defense systems and find that increased expression enhances their protection range, albeit at a cost of autoimmunity.

www.nature.com

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Malcolm White @mfwhite2.bsky.social · Jul 14

Here we show how the type III signalling molecule SAM-AMP is bound and degraded by a specialised lyase enzyme encoded in cellular and phage genomes. More great work by @haotianchi.bsky.social and the team. @uniofstandrews.bsky.social
academic.oup.com/nar/article/...

SAM-AMP lyases in type III CRISPR defence

Abstract. Type III CRISPR systems detect non-self RNA and activate the enzymatic Cas10 subunit, which generates nucleotide second messengers for activation

academic.oup.com

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Rob Edwards @linsalrob.bsky.social · Jul 7

We made structural predictions of representatives of each #PHROG from #phage genomes, and put the whole lot online. You can browse through montages or go to your favourite phrog directly and download its PDB.

💻🧬 #phagesky

linsalrob.github.io/PHROG_struct...

PHROG Structure Gallery

linsalrob.github.io

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Michael Brockhurst @brockhurstlab.bsky.social · Jul 3

How phages trigger antiphage defence systems is a big unknown in the field. Looks great!
#mevosky

Emmanuele Severi @emmseveri.bsky.social · Jul 3

#phagesky

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

Identifying phage proteins that activate the bacterial innate immune system

Bacteria have evolved sophisticated antiphage systems that halt phage replication upon detecting specific phage triggers. Identifying phage triggers is crucial to our understanding of immune signaling...

www.biorxiv.org

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Tung Le @tunglejic.bsky.social · Jul 2

Finally published! Many thanks to the reviewers and editor whose comments & suggestions improved this work significantly more than the first preprint version!!!

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

Expanding the diversity of bacterial DNA partitioning: A CTP-independent ParABS system for plasmid partitioning in Streptomyces | PNAS

The ATP- and CTP-dependent ParA-ParB-parS segrosome is a macromolecular complex that segregates chromosomes/plasmids in most bacterial species. CTP...

www.pnas.org

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Cell Host & Microbe @cp-cellhostmicrobe.bsky.social · Jun 26

Phage DNA modifications evade defense

Phage DNA modification adds arabinose to cytosines via hydroxy linkage (5ara-hC) w/ potential double & triple arabinosylation. Arabinosylated phages are protected from DNA-targeting CRISPR-Cas & restriction modification
www.cell.com/cell-host-mi...

Phage arabinosyl-hydroxy-cytosine DNA modifications result in distinct evasion and sensitivity responses to phage defense systems

Mahler et al. describe a phage DNA modification that adds arabinose to cytosines via a hydroxy linkage. This 5ara-hC modification can be further modified to double and triple arabinosylation by phage-...

www.cell.com

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Aleksei Agapov @alekseiagapov.bsky.social · Jun 26

Hey, thanks for the idea! Looks a bit wild, but there might be something in it...

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David Sünderhauf @davvi36.bsky.social · Jun 24

. @emgoodall.bsky.social presenting her cool new transposon-based method on discovery of novel small proteins #EESMicrobiology

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Aleksei Agapov @alekseiagapov.bsky.social · Jun 24

Presenting a poster about Pseudomonas defence systems at #EESMicrobiology in Heidelberg. If you happen to like it, don't forget to check out our consortium @multidefence.bsky.social

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Anna Olina @annaolina.bsky.social · Jun 24

Happily representing @multidefence.bsky.social at the #EESMicrobiology in Heidelberg!
Come to my poster if interested in prophage-mediated phage defence!
Also don't miss @emgoodall.bsky.social's talk today, and @alekseiagapov.bsky.social and @davvi36.bsky.social posters!

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David Sünderhauf @davvi36.bsky.social · Jun 24

Made it to Heidelberg for #EESMicrobiology @events.embl.org!
Find me at poster 240 and make to check out @annaolina.bsky.social & @alekseiagapov.bsky.social 's posters and @emgoodall.bsky.social 's talk to see everyone from the lab 😁

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Aleksei Agapov @alekseiagapov.bsky.social · Jun 21

That was fun!

Multi-Defence @multidefence.bsky.social · Jun 18

Great to get together in Manchester last week for our consortium’s annual meeting – halfway through our 5-year collaboration! Inspiring discussions, exciting updates, and lots of ideas ahead. Excited for what’s next! 💡🔬🤝 #Science #Microbiology #TeamScience

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Jamie Hall @jpjhall.bsky.social · Jun 20

🚨 Reminder! You have just over two weeks to submit an abstract, if you want to present at the @microbiologysociety.org meeting "Understanding and predicting microbial evolutionary dynamics" in Liverpool in November! #microsky 🦠🧫🔬

Jamie Hall @jpjhall.bsky.social · May 2

‼️Update! Abstract submission is now open for the 2025 Liverpool UK @microbiologysociety.org meeting on "Understanding and predicting microbial evolutionary dynamics”! Deadline July 7th #microsky 🧪🧫🦠 microbiologysociety.org/event/societ...

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Anna Kanevskaya @annakanevskaya.bsky.social · Apr 7

News from the world of pAgos:
We explored a distinct clade of short pAgos associated with HNH nuclease partners, which we named SPARHA, and discovered that they protect bacteria from phages and plasmids via abortive infection. Upon activation, SPARHA oligomerizes, forming filaments.
A long 🧵

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Clàudia Morros Bernaus @claudiamb98.bsky.social · Apr 13

Had a great time today at #ESCMIDGlobal presenting on using CRISPR-Cas9 to kill E. coli ST131 and the emergence of different escape populations. Big thanks to @escmid.bsky.social and everyone who came by!

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Itai Yanai @itaiyanai.bsky.social · Apr 11

Is the genome just a bag of genes? A new paper in Science now reports that for two thirds of an organisms' genes the position along the chromosome is actually very tightly constrained! Amazing work from my favorite night scientist
Martin Lercher and his team!
www.science.org/doi/10.1126/...

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Multi-Defence @multidefence.bsky.social · Apr 10

🔬 Three fronts in bacterial defense!
At EMBO symposium this week in Paris, our PIs showcased:
• @mfwhite2.bsky.social: cyclic nucleotide defence signaling
• Prof. Stineke Van Houte: prophage warfare in P. aeruginosa
• Prof. Tim Blower: autoregulating toxins & phage defence

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Aleksei Agapov @alekseiagapov.bsky.social · Apr 3

Finishing the Microbial Warfare session strong!

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Aleksei Agapov @alekseiagapov.bsky.social · Apr 2

Phage vs Phage from @annaolina.bsky.social at #Microbio25. Fantastic talk!

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