Asaf Levy

Asaf Levy

@asaflevylab.bsky.social

Interested in computational biology, microbial toxins, plant microbiome, and microbial adaptation to different hosts. PI at the Hebrew University of Jerusalem. https://www.asaflevylab.com/ Expressing my personal opinions.

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Asaf Levy
@asaflevylab.bsky.social

A new paper from the lab on virus-like particles called eCISs www.nature.com/articles/s41... How bacteria evolved thousands of precision nanoinjectors? Some bacteria don’t secrete toxins — they inject them using phage-derived machines called extracellular contractile injection systems (eCISs).

nature.comA comprehensive catalogue of receptor-binding domains in extracellular contractile injection systems - Nature CommunicationsExtracellular contractile injection systems (eCISs) are bacteriophage tail-derived toxin delivery complexes that are present in many prokaryotes. Here, the authors present an analysis of eCIS tail fib...
Asaf Levy
@asaflevylab.bsky.social

My collaborator Netanel Tzarum developed a cool method to express and purify highly toxic bacterial proteins. We helped a bit. Very useful for anyone working with toxin-antitoxin or effector-immunity systems. Now in Microbial Biotechnology enviromicro-journals.onlinelibrary.wiley.com/doi/10.1111/...

enviromicro-journals.onlinelibrary.wiley.comModular Platform for Recombinant Production of Highly Toxic Bacterial ProteinsA modular recombinant production platform based on transient toxin neutralization enables scalable expression and purification of intrinsically toxic proteins. The approach combines natural toxin–imm...
Asaf Levy
@asaflevylab.bsky.social

I love the vision at the end of Nagel et al. Science 2002: "the ability of ChR1 to mediate a large light-switched H+ conductance in oocytes holds promise for the use of ChR1 as a tool for measuring and/or manipulating electrical and proton gradients across cell membranes, simply by illumination."

science.orgChannelrhodopsin-1: A Light-Gated Proton Channel in Green AlgaePhototaxis and photophobic responses of green algae are mediated by rhodopsins with microbial-type chromophores. We report a complementary DNA sequence in the green alga Chlamydomonas reinhardtiithat ...
Florent Waltz@florentwaltz.bsky.social

Huge congratulations to all three Nobel Laureates, and especially Peter Hegemann! 👏 His seminal work on the green alga Chlamydomonas 🦠 laid the foundation for optogenetics. Thank you for putting Chlamy in the spotlight! ✨ Proof that groundbreaking discoveries don't always come from animal models! 🔬

Asaf Levy reposted

Florent Waltz
@florentwaltz.bsky.social

Huge congratulations to all three Nobel Laureates, and especially Peter Hegemann! 👏 His seminal work on the green alga Chlamydomonas 🦠 laid the foundation for optogenetics. Thank you for putting Chlamy in the spotlight! ✨ Proof that groundbreaking discoveries don't always come from animal models! 🔬

Nobel Prize@nobelprize.org

BREAKING NEWS The 2026 Nobel Prize in Physiology or Medicine has been awarded to Karl Deisseroth, Peter Hegemann and Georg Nagel “for their discoveries concerning light-gated ion channels and optogenetics.”

Asaf Levy
@asaflevylab.bsky.social

In October we are starting year 8 (I think) of the virtual microbiology journal club (on Zoom) with fantatstic speakers, as usual. Most talks are about bacteria. If you (PIs, trainees, anyone interested in science) want to be included in the mailing list - shoot me an email. alevy@mail.huji.ac.il

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Asaf Levy
@asaflevylab.bsky.social

We observed that T6SS effectors tend to be longer, more hydrophilic, charged, and ordered, and to reside next to or fused to T6SS genes significantly more than non-T6Es. Common protein domains are depleted from effectors. Another new effector is likely a non-specific metalloprotease

Asaf Levy
@asaflevylab.bsky.social

that was toxic in bacterial cyto/periplasm and in yeast cells. Mutations in the metal binding pocket destroyed its activity. This is another fun collaboration with my friend Dr. Netanel Tzarum. Stay tuned for another paper resulting from this collaboration which will be published in a few days.

Asaf Levy
@asaflevylab.bsky.social

Chryseobacterium, showed a beautiful phenotype. This toxin, that we named the "moon toxin", targets the peptidoglycan. When expressed in E. coli, it quickly leads to spherical aggregated cells, with inner membrane separation, and gradual peptidoglycan degradation in a unipolar manner,

Asaf Levy
@asaflevylab.bsky.social

demonstrating a moon-like structural phenotype. You can observe the cell wall unipolar accumulation and degradation in blue. We didn't expect to E. coli looking so weird. We provide predictions of 19,958 T6SS effector candidates in 2,559 T6SS-encoding bacterial genomes.

Asaf Levy
@asaflevylab.bsky.social

I found this paper from 2002 about plant-fungal symbiosis which enables both partners to grow above 45C (!) in geothermal soils in Lassen Volcanic and Yellowstone National Parks. As far as I understand te genetic basis of this thermotolerance is still unknown. www.science.org/doi/10.1126/...

science.orgThermotolerance Generated by Plant/Fungal SymbiosisAll plants studied in natural ecosystems are symbiotic with fungi (1), which obtain nutrients while either positively, negatively, or neutrally affecting host fitness (2). Plant adaptation to selectiv...

Asaf Levy reposted

Omri Finkel עמרי عُمري
@finkel-lab.bsky.social

Michal Breker and I started our labs around the same time. Michal studies Chlamydomonas, and I plant microbiota. We joined forces to see how our bugs interact. This led us down a long and winding road, with 3 amazing PhDs and help from many friends. This is the first product of this collaboration.

biorxiv.orgConserved inhibitory mechanisms of root-associated bacteria towards Arabidopsis thaliana and Chlamydomonas reinhardtiiSoil bacteria colonize plants without causing visible disease, yet many suppress host growth. The prevalence and evolutionary reach of this cryptic inhibition are unknown, because phenotyping hundreds...
Asaf Levy
@asaflevylab.bsky.social

Nice experimental evolution work from @cascaleslab.bsky.social on the mechanisms by which T6SS is lost during evolution when present with T6SS-immune competing bacteria, compared to its maintenance when competitors are T6SS susceptible. www.cell.com/current-biol...

cell.comExperimental evolution reveals genetic routes for adaptive loss of the antibacterial type VI secretion systemTaillefer et al. show that a bacterial type VI secretion system is lost or attenuated during experimental evolution when it provides no competitive advantage but is maintained in the presence of susceptible competitors. T6SS inactivation arises through diverse regulatory and structural mutations, revealing how ecological context shapes antibacterial weapon evolution.
Asaf Levy
@asaflevylab.bsky.social

Happy new Jewish year to the Levy lab friends, collaborators, and Reviewers #2 around the world. May the next one will be much more peaceful. (Pic from lab's bday in Palmachim beach 2 days ago).

Asaf Levy
@asaflevylab.bsky.social

Cool stuff from the Sorek lab on the functional connection between anti-phage bacterial immunity and plant immunity and the ways to manipulate these. 1st author: Dr. Ohad Roth @soreklab.bsky.social www.biorxiv.org/content/10.6...

biorxiv.orgPlant pathogens cleave 2′cADPR to suppress TIR immune signalingSmall molecules produced by TIR (Toll-interleukin-1 receptor) domains are essential for plant immune signaling. A central TIR-derived signal is 2ʹcADPR, a cyclic ADP-ribose (ADPR) molecule that is gen...
Asaf Levy
@asaflevylab.bsky.social

Amazing achievement to Bonnie Bassler. The medal is shared with the most creative scientists ever lived since the 18th century.

The Royal Society@royalsociety.org

We’re very happy to announce the winners of our medals and awards for 2026, recognised for their outstanding contributions to scientific discovery, public engagement and research culture. #RSMedals royalsociety.org/news/2026/08...

royalsociety.orgThe Royal Society announces the medals and awards recipients 2026 | Royal SocietyProfessor Bonnie Bassler awarded world’s oldest scientific prize for research on how bacteria talk to each other
Asaf Levy
@asaflevylab.bsky.social

For nearly 20 years I have used this pic as my FB profile image and already forgot where it was taken by my wife. But today, while hiking with my kids in Aigüestortes i Estany de Sant Maurici National Park (Spain) I found the exact corner and my sons reproduced it.

Asaf Levy
@asaflevylab.bsky.social

The pope promotes people to saints after having evidence for their miracles. Pope Leo already canonized 9 people in his short term. Pope Francis: more than 60. And I am thinking about this graph

Asaf Levy
@asaflevylab.bsky.social

The only people who ever loved war for long were profiteers, generals, staff officers, and whores. They all had the best and finest time of their lives and most of them made the most money they had ever made. Hemingway, 1936

Asaf Levy
@asaflevylab.bsky.social

We're recruiting a fungal biologist to our friendly department at the Hebrew University of Jerusalem, Rehovot, Israel. For details contact our chair. Talented non-Israli applicants are welcome to apply. See below.

Asaf Levy
@asaflevylab.bsky.social

A cool work from Ilya and Rotem on the 'damage-associated molecular pattern' that bacteria sense to detect phage attack (DNA degradation leading to increase in methylated nucleotides) and the immune response as abortive infection. www.science.org/doi/10.1126/...

science.orgBacteria sense virus-induced genome degradation via methylated mononucleotidesPhages often degrade the genome of their bacterial host to individual nucleotides. Here we describe Metis, a bacterial defense system that directly senses phage-mediated host genome degradation. Metis...

Asaf Levy reposted

Eric Topol
@erictopol.bsky.social

On our 250th birthday, celebrating the contribution of immigrants and international collaboration —46% of people with doctoral-level degrees working in US science and engineering fields are foreign-born