Luis E. Valentin-Alvarado
luisvalentin.bsky.social
Luis E. Valentin-Alvarado
@luisvalentin.bsky.social
microbes, metagenomes, protein structures and volleyball
Reposted by Luis E. Valentin-Alvarado
Now out in Science! Cyclin-dependent kinases (CDKs) are key regulators of the cell cycle. In @vcushing.bsky.social's magnum opus, we use #cryoEM to figure out how the CDK-activating kinase recognises CDKs to fully activate them - a key step in cell cycle control.
www.science.org/doi/10.1126/...
Structural basis of T-loop–independent recognition and activation of CDKs by the CDK-activating kinase
Cyclin-dependent kinases (CDKs) are prototypical regulators of the cell cycle. The CDK-activating kinase (CAK) acts as a master regulator of CDK activity by catalyzing the activating phosphorylation o...
www.science.org
October 16, 2025 at 7:17 PM
Reposted by Luis E. Valentin-Alvarado
Reposted by Luis E. Valentin-Alvarado
Most plasmids described in E. coli are small compared to the megaplasmids we identified here! Check out the preprint if you want to learn about these mysterious large elements and their potential functions 🧬. I’m very grateful to have had the opportunity to work on this in @banfieldlab.bsky.social
Megaplasmids associate with Escherichia coli and other Enterobacteriaceae https://www.biorxiv.org/content/10.1101/2025.09.30.679422v1
October 1, 2025 at 5:10 AM
Reposted by Luis E. Valentin-Alvarado
Now online at @nature.com we show how the Panoptes defense system protects against viruses that attempt immune evasion - and expands our understanding of the role of oligonucleotides in immunity.

Check out this work co-led with @benadler.bsky.social here:

www.nature.com/articles/s41...
A miniature CRISPR–Cas10 enzyme confers immunity by inhibitory signalling - Nature
Panoptes, an anti-phage defence system against virus-mediated immune suppression, is revealed.
www.nature.com
October 2, 2025 at 3:01 AM
Reposted by Luis E. Valentin-Alvarado
New paper online at @nature.com from co-leads @erinedoherty.bsky.social + @benadler.bsky.social !
Now online at @nature.com we show how the Panoptes defense system protects against viruses that attempt immune evasion - and expands our understanding of the role of oligonucleotides in immunity.

Check out this work co-led with @benadler.bsky.social here:

www.nature.com/articles/s41...
A miniature CRISPR–Cas10 enzyme confers immunity by inhibitory signalling - Nature
Panoptes, an anti-phage defence system against virus-mediated immune suppression, is revealed.
www.nature.com
October 2, 2025 at 3:25 AM
Reposted by Luis E. Valentin-Alvarado
Our story describing the Panoptes bacterial immune defense system is now finally peer-reviewed and published today! www.nature.com/articles/s41...
The Panoptes system uses decoy cyclic nucleotides to defend against phage - Nature
The Panoptes antiphage system defends bacteria by detecting phage-encoded counter-defences that sequester cyclic nucleotide signals, triggering membrane disruption and highlighting a broader strategy of sensing immune evasion through second-messenger surveillance.
www.nature.com
October 1, 2025 at 4:05 PM
Reposted by Luis E. Valentin-Alvarado
Today in @nature.com , we highlight how a cousin of CRISPR-Cas10, mCpol, establishes an evolutionary trap in anti-phage immune systems.

Check out @erinedoherty.bsky.social and my work from @doudna-lab.bsky.social lab here:
www.nature.com/articles/s41...
A miniature CRISPR–Cas10 enzyme confers immunity by inhibitory signalling - Nature
Panoptes, an anti-phage defence system against virus-mediated immune suppression, is revealed.
www.nature.com
October 1, 2025 at 5:57 PM
Reposted by Luis E. Valentin-Alvarado
Our Department of Microbiology & Immunology at UCSF is running a faculty search this year for a new Assistant Professor! Please see the ad below for details. Searching for a great colleague, mentor, and scientist!
aprecruit.ucsf.edu/JPF05807
Microbiology and Immunology – Faculty Position (Ladder Rank) – Assistant Professor
University of California, San Francisco is hiring. Apply now!
aprecruit.ucsf.edu
September 25, 2025 at 5:51 PM
Reposted by Luis E. Valentin-Alvarado
Join us tomorrow if you can. Link below to register.
⏰ Last call! The human #microbiome webinar is tomorrow.

See how #PacBio HiFi sequencing delivers clarity with full-length 16S rRNA and shotgun metagenomics, revealing strain-level insights, novel taxa, and functional pathways.

Register now: bit.ly/46wBttB
September 24, 2025 at 11:21 PM
Reposted by Luis E. Valentin-Alvarado
New blog post!

metaMDBG (@gaetanbenoit.bsky.social) and Myloasm (@jimshaw.bsky.social) have had recent releases, so I updated the benchmarks from the Autocycler paper:
rrwick.github.io/2025/09/23/a...

Both tools improved considerably! Time to update your conda environments 😄
Benchmark update: metaMDBG and Myloasm
a blog for miscellaneous bioinformatics stuff
rrwick.github.io
September 23, 2025 at 1:53 AM
Reposted by Luis E. Valentin-Alvarado
The Department of Biology at Colorado State University is hiring an Assistant Professor in the area of plant-microbe interactions! Please spread the word!

jobs.colostate.edu/postings/165...
Assistant Professor Plant-Microbe Interactions
We seek a creative, collaborative, and visionary plant biologist to establish an internationally recognized research program at the forefront of plant-microbe interactions aimed at understanding how t...
jobs.colostate.edu
September 8, 2025 at 3:45 PM
Reposted by Luis E. Valentin-Alvarado
❤️❤️❤️ CSU. Fort Collins is a lovely place to live, and students / faculty are awesome. I should know, I taught there for 15 years! Apply!
September 8, 2025 at 4:07 PM
Reposted by Luis E. Valentin-Alvarado
This is the dept where I got my PhD! Hiring for microbiology!
September 8, 2025 at 4:16 PM
Reposted by Luis E. Valentin-Alvarado
How can we understand the earliest events in evolution of eukaryotic immunity? @yao-li.bsky.social reports incredible molecular fossils of complete bacterial-like operons in eukaryotes that illuminate how animal immunity was first acquired from anti-phage defense

www.biorxiv.org/content/10.1...
September 5, 2025 at 10:13 AM
Reposted by Luis E. Valentin-Alvarado
🦠Exciting PhD opportunity @ ETH Zürich!
Our Environmental Microbiology group is looking for a motivated student to study microbial processes in peatland restoration — from fieldwork to metagenomics and lab experiments.

🗓 Start: Spring 2026
⏳ Deadline: 3 Oct 2025
👉 Apply: lnkd.in/eSPiy6vQ
Please 🔁
LinkedIn
This link will take you to a page that’s not on LinkedIn
lnkd.in
September 3, 2025 at 5:46 PM
Reposted by Luis E. Valentin-Alvarado
📢 🦠 A new methanotroph from Czech peat! Through an effort led by PhD student in my group Justus Nweze we isolated and describe a new CH4-muncher. Potential for a flexible (annaerobic) metabolisms and cool pH adaptations.

www.biorxiv.org/content/10.1...
#microbesky #microbiomesky
Genomic and physiological characterization of 'Candidatus Methylocystis sumavensis', a novel acid-tolerant methanotroph from peatland
Methanotrophic bacteria in peatlands mitigate emissions of methane (CH4), a potent greenhouse gas. Yet, the identity, physiology, and adaptive traits of methanotrophs inhabiting acidic peatlands are s...
www.biorxiv.org
September 1, 2025 at 10:39 AM
Reposted by Luis E. Valentin-Alvarado
The beautiful, ever-expanding universe of viral proteins targeting nucleotide immune signals!

Paper by @reneechang.bsky.social in @cp-molcell.bsky.social on a nucleotide sponge www.cell.com/molecular-ce...

and preprint by @doudna-lab.bsky.social on viral nucleases www.biorxiv.org/content/10.1...
A widespread family of viral sponge proteins reveals specific inhibition of nucleotide signals in anti-phage defense
Chang et al. discover anti-CBASS 4 (Acb4), a family of viral sponges that inhibits bacterial immunity by sequestering nucleotide immune signals. Acb4 homologs in phages that infect hosts across all ma...
www.cell.com
August 22, 2025 at 9:02 PM
Reposted by Luis E. Valentin-Alvarado
New pre-print from Doudna lab members @erinedoherty.bsky.social & @jnoms.bsky.social

Here we explore how recurrent adaptation of a single anti-defense protein fold enables evasion of distinct immune systems.
Excited to share our new preprint co-led by @jnoms.bsky.social!

Here we reveal an exceptional diversity of viral 2H phosphodiesterases (PDEs) that enable immune evasion by selectively degrading oligonucleotide-based messengers. This 2H PDE fold has evolved striking substrate breath & specificity.
Divergent viral phosphodiesterases for immune signaling evasion
Cyclic dinucleotides (CDNs) and other short oligonucleotides play fundamental roles in immune system activation in organisms ranging from bacteria to humans. In response, viruses use phosphodiesterase...
www.biorxiv.org
August 22, 2025 at 7:36 PM
Reposted by Luis E. Valentin-Alvarado
At the request of @bradleyph.bsky.social, we have now added the Bacterial and Archaeal trees (credit to @aroneys.bsky.social) used to infer the GlobDB taxonomy to the website globdb.org

Feel free to reach out if there's other resources you'd like to see added. No promises, but happy to chat 🖥️🧬🦠
home | GlobDB
globdb.org
August 11, 2025 at 7:52 PM
Reposted by Luis E. Valentin-Alvarado
New preprint up now!

Interested in the evolution of halophily within DPANN archaea we decided to investigate the sister phylum to the Nanohaloarchaeota, GTDB phylum EX4484-52, for which we propose the name Caliditerrarchaeota
www.biorxiv.org/content/10.1...
Caliditerrarchaeota, a new sister to Nanohaloarchaeota, provides insights into the evolution of DPANN halophily
The Nanohaloarchaeota are a clade of halophilic symbionts with small cells and genomes. Originally placed within the Euryarchaeota, they are now widely thought to belong to the DPANN archaea. However,...
www.biorxiv.org
August 8, 2025 at 6:49 AM
Reposted by Luis E. Valentin-Alvarado
Excited to finally share this work!
We noticed a pair of genes - a nuclease and a protease - shuffles between antiviral systems. We show how proteolysis activates the nuclease, triggering defense in known and unknown immune contexts.
tinyurl.com/2uwwy4ty
Recurrent acquisition of nuclease-protease pairs in antiviral immunity
Antiviral immune systems diversify by integrating new genes into existing pathways, creating new mechanisms of viral resistance. We identified genes encoding a predicted nuclease paired with a trypsin...
tinyurl.com
July 29, 2025 at 3:48 PM
Reposted by Luis E. Valentin-Alvarado
‼️ New pre-print from co-leads @owentuck.bsky.social and Jason Hu! Check out this fascinating example of how coevolution enables defense system innovation.
Excited to finally share this work!
We noticed a pair of genes - a nuclease and a protease - shuffles between antiviral systems. We show how proteolysis activates the nuclease, triggering defense in known and unknown immune contexts.
tinyurl.com/2uwwy4ty
Recurrent acquisition of nuclease-protease pairs in antiviral immunity
Antiviral immune systems diversify by integrating new genes into existing pathways, creating new mechanisms of viral resistance. We identified genes encoding a predicted nuclease paired with a trypsin...
tinyurl.com
July 29, 2025 at 9:18 PM
Reposted by Luis E. Valentin-Alvarado
Very proud to have our lab’s first work published in @cp-cellhostmicrobe.bsky.social!

In this work, we use functional metagenomics to find phage defenses from human and soil microbiomes!

Congrats to first author @luis840alberto.bsky.social !

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

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July 29, 2025 at 2:53 PM
Reposted by Luis E. Valentin-Alvarado
if i were a better person i would do a tweetorial on our recent paper - but, hey, read the paper. its right there, waiting for you. #Giantvirus #histones are cool! their #nucleosomes are cool. check it out.! thats the tweetorial.
rdcu.be/exXBX
July 26, 2025 at 7:09 PM