Asaf Levy (@asaflevylab)

Expanded screening and analysis of Photorhabdus virulence cassette (PVC) signal peptides reveals an anti-phagocytotic effector As one of the typical extracellular contractile injection systems (eCISs), Photorhabdus virulence cassette (PVC) can be released from bacterial cells …

Another fun collaboration with Feng Jiang's lab on the extracellular contractile injection system of Photorhabdus (PVC):
www.sciencedirect.com/science/arti...

10.03.2026 13:05 👍 1 🔁 0 💬 0 📌 0

Ubercool.
Toxin-antitoxin systems were discovered 40 years ago in E. coli, and later on in many genomes including in euks.
Now the 1st TA system is reported in the mouse genome!
It affects embryo killing. Amazing distribution of a simple yet efficient genetic system
www.biorxiv.org/content/10.6...

10.03.2026 12:22 👍 28 🔁 14 💬 2 📌 3

Kevin Foster's group provides additional support that similar contact independent weapons in P. aeruginosa (a microbe armed to the teeth) are specialised for combat under different environmental conditions. This was shown a few years ago by Mougous Lab for T6SS.
www.biorxiv.org/content/10.6...

09.03.2026 11:04 👍 2 🔁 0 💬 0 📌 0

Train booking in Germany!

06.03.2026 12:02 👍 11 🔁 3 💬 1 📌 0

06.03.2026 12:41 👍 2 🔁 0 💬 0 📌 0

Tel Aviv between ballistic missiles

06.03.2026 12:36 👍 3 🔁 0 💬 1 📌 0

Honeymoon

02.03.2026 15:50 👍 0 🔁 0 💬 0 📌 0

انشاالله

01.03.2026 06:17 👍 2 🔁 0 💬 0 📌 0

I despise Netanyahu.
I don't like Trump.
But if these two will liberate the Iranian people from ~50 years of dictatorship and oppression, I am for it.

Celebrations in San Diego yestderday.
Sent by a Baha'i friend who had to escape Iran due to religious oppresion and could pursue a PhD in the US.

01.03.2026 06:13 👍 7 🔁 0 💬 2 📌 0

Specialization of independently acquired flagellar FliC proteins in plant-associated Sphingomonas balances swimming and immunogenicity Plants monitor their environment for microbial invaders using pattern-recognition receptors that detect microbe-associated molecular patterns (MAMPs). Flagellin, the main component of bacterial flagellum, contains the flg22 epitope recognized by the plant immune receptor FLS2. Immune recognition can create an evolutionary conflict, requiring bacteria to balance flagellar function and immune evasion. Here, we show that plant-associated Sphingomonads resolve this constraint by partitioning two flagellar functions, motility and colonization, across two divergent and independently acquired flagellin genes. Comparative genomics revealed widespread coexistence of FliC proteins expressing either an immunogenic variant (FliC-H) or a non-immunogenic variant (FliC-L). The non-immunogenic FliC-L is necessary and sufficient for full directional swimming, whereas FliC-H is dispensable for swimming, but sufficient for full attachment and colonization. Flagellin expression patterns mirror these functions. Thus, FLS2 recognizes the flagellar variant required for colonization rather than motility, potentially restricting colonizing bacteria from entering internal leaf and root tissues. ### Competing Interest Statement The authors have declared no competing interest. European Molecular Biology Organization, https://ror.org/04wfr2810, ALTF 743-2019 U.S. National Science Foundation, https://ror.org/021nxhr62, IOS-2416244 Howard Hughes Medical Institute, https://ror.org/006w34k90, Jefferey L. Dangl Natural Sciences and Engineering Research Council, https://ror.org/01h531d29, 532852-2019 Knut and Alice Wallenberg Foundation, https://ror.org/004hzzk67, 2021.0102

A new paper from @dorruss12.bsky.social and Jeff Dangl on two flagellins in plant-associated Sphingomonas used for motility or host colonization.

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

28.02.2026 18:46 👍 5 🔁 2 💬 0 📌 0

Tryptophanase disruption promotes insect–bacterium mutualism - Nature Microbiology Disruption of a single gene encoding tryptophanase makes Escherichia coli mutualistic in a stinkbug model owing to the accumulation of tryptophan and a reduction in toxic indole. This gene is typicall...

Disruption of a single gene, tnaA, encoding tryptophanase makes E. coli mutualistic to stinkbug, resulting in the accumulation of tryptophan and the reduction of toxic indole. www.nature.com/articles/s41...

28.02.2026 11:03 👍 8 🔁 3 💬 0 📌 0

My 19th marathon.
Great weather, wonderful views of Tel Aviv, and many kids giving high fives made it into a fun run.

Hoping another war shall not start in the middle east although the signs are not encouraging.

27.02.2026 21:41 👍 11 🔁 0 💬 0 📌 0

The editor:
We need a catchy title

Daniel Defoe:
The Life and Strange Surprizing Adventures of Robinson Crusoe, of York, Mariner: Who lived Eight and Twenty Years, all alone in an un-inhabited Island on the Coast of America, near the Mouth of the Great River of Oroonoque; Having been cast on ...

24.02.2026 19:16 👍 3 🔁 1 💬 0 📌 0

Love the Eilat mountains.
#fiseb2026

24.02.2026 16:22 👍 4 🔁 0 💬 0 📌 0

Scientists have seen Asgard archaea crawling for the first time. When it comes to the origin of eukaryotes, this is like seeing a feathered dinosaur in the wild. (Video courtesy of Philipp Ralder)

18.02.2026 20:09 👍 470 🔁 136 💬 10 📌 19

Giant DNA viruses encode a hallmark translation initiation complex of eukaryotic life Giant DNA viruses encode a cap-binding complex homologous to eIF4F, the defining translation-initiation complex of eukaryotes. The viral cap-binding complex is required for viral protein synthesis and...

Cool finding:
Giant DNA viruses encode a hallmark translation initiation complex of eukaryotic life: Cell www.cell.com/cell/fulltex...

18.02.2026 13:33 👍 2 🔁 1 💬 0 📌 0

And to Debbie as well!

15.02.2026 06:47 👍 2 🔁 0 💬 0 📌 0

The Dead Sea

14.02.2026 15:31 👍 6 🔁 0 💬 0 📌 0

A nice spot to check exams

06.02.2026 12:44 👍 2 🔁 0 💬 0 📌 0

#ProtistsOnSky
no 'swimming' by 𝘝𝘢𝘮𝘱𝘺𝘳𝘦𝘭𝘭𝘢, definitively no 'staying still'. just a relaxed walk towards the lunch...

02.02.2026 00:00 👍 200 🔁 74 💬 5 📌 5

Aeromonas adhesins facilitate kin and non-kin attachment to enable T6SS-mediated antagonism in liquid Bacterial ability to deploy the type VI secretion system (T6SS) against rivals requires prolonged cell-cell interactions. Such interactions are facilitated on solid surfaces but are assumed to be absent in liquid, leading to the conventional dismissal of T6SS-mediated competition in liquid environments. Here, we find that Aeromonas jandaei employs its T6SS to eliminate diverse bacterial competitors in liquid media. Using a workflow that monitors interbacterial competition via prey luminescence, we demonstrate that auto-aggregation and co-aggregation, facilitated by distinct adhesins, enable kin and non-kin recognition and intoxication in a T6SS-dependent manner. Furthermore, we show that another marine bacterium, Vibrio coralliilyticus , employs T6SS to intoxicate rivals in liquid media. Collectively, our results indicate that T6SS-mediated competition in liquid is more common in marine bacteria than previously anticipated, and can be facilitated by diverse molecular mechanisms that govern cell aggregation. ### Competing Interest Statement The authors have declared no competing interest. Israel Science Foundation, https://ror.org/04sazxf24, 1362/21, 2174/22 Swiss National Science Foundation, 51NF40_180541

It is widely accepted that #T6SS -mediated intoxication occurs only on solid surfaces, where prolonged cell-cell interactions are forced, and not in liquid environments. But is this generalization true? Our new preprint says it isn't. A 🧵 ...
biorxiv.org/content/10.6...
🦠

28.01.2026 12:36 👍 28 🔁 13 💬 3 📌 0

Lab trip

01.02.2026 07:58 👍 7 🔁 0 💬 0 📌 0

@jbdsf.bsky.social

31.01.2026 10:04 👍 1 🔁 0 💬 0 📌 0

The Punchline One of the worst players in the NHL gets voted into the All-Star Game.

10 years ago today was one of craziest moments in world sports. The 2016 National Hockey League All-Star Game.

Listen to the great story over here wonderfully told by RadioLab @latif.bsky.social

www.wnycstudios.org/story/the-pu...

31.01.2026 09:55 👍 1 🔁 0 💬 1 📌 0

Multiple protein structure alignment at scale with FoldMason Protein structure is conserved beyond sequence, making multiple structural alignment (MSTA) essential for analyzing distantly related proteins. Computational prediction methods have vastly extended ou...

FoldMason is out now in @science.org. It generates accurate multiple structure alignments for thousands of protein structures in seconds. Great work by Cameron L. M. Gilchrist and @milot.bsky.social.
📄 www.science.org/doi/10.1126/...
🌐 search.foldseek.com/foldmason
💾 github.com/steineggerla...

30.01.2026 06:11 👍 300 🔁 147 💬 4 📌 3

Great new story from Sophie Helaine and Molly Sargen!

www.helainelab.com

28.01.2026 23:01 👍 35 🔁 18 💬 0 📌 0

Saw it. Very cool

27.01.2026 06:47 👍 1 🔁 0 💬 0 📌 0

thanks Itzik

26.01.2026 19:55 👍 0 🔁 0 💬 0 📌 0

congrats Aaron!

26.01.2026 18:47 👍 1 🔁 0 💬 0 📌 0

A great work by Nimrod Nachmias in collaboration with Feng Jiang.

26.01.2026 13:26 👍 0 🔁 0 💬 0 📌 0

Asaf Levy

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