Philipp Radler
@radler92.bsky.social
I spent most of my days at work watching fascinating Archaea in the microscope at @archaea-vienna.bsky.social. To cope with stress by science I hike and immerse myself with D&D!
Our new preprint is out! We investigate chromosome organization in obligate mammalian symbionts and show that these bacteria maintain stable chromosome orientations while displaying conserved lifestyle-associated chromosome architectures across species. www.biorxiv.org/cgi/content/...
I'm happy to share the first paper from my postdoc work: www.biorxiv.org/content/10.6... How does RecA find one homologous sequence in an entire chromosome -and what turns that encounter into a repair-competent one? We find that DNA topology is the gatekeeper !! 1/10
Chromosome topology gates productive RecA homology search
In homologous recombination, DNA repair depends on recombinase filaments finding homologous templates on chromosomes whose topology is continually remodeled by replication and transcription. How dynam...
biorxiv.org
So happy to share our new paper out now in @natmicrobiol.nature.com! We establish Pirsonia-Coscinodiscus as a model pathosystem and uncover how this tiny parasite infects and kills bloom-forming marine diatoms 🌊🦠 rdcu.be/fuQyF
Excited to share our new preprint led by Fred and me in collaboration with the archaeal community! We found that the molecular foundation of histone-based chromatin has pre-eukaryotic roots in Asgard archaea. (1/4) #ArchaeaSky www.biorxiv.org/content/10.6...
Emergence of histone-based chromatin complexity in Asgard archaea
The emergence of the eukaryotes coincided with the diversification of histone proteins and their post-translational modifications by enzymes that constitute the core of eukaryotic chromatin. Yet the e...
biorxiv.org
Parasitic bacteria feeding on their hosts’ RNA!? New cultures and Patescibacteriota/Minisyncoccota/CPR continue to surprise us… www.biorxiv.org/content/10.6...
A representative of a ubiquitous bacterial lineage parasitically feeds on host RNA
Cellular metabolism is widely understood as an integrated network of redox reactions, energy conservation, and biosynthetic pathways. Here we show that across diverse prokaryotic lineages, loss of red...
biorxiv.org
Very excited to share my first preprint! Great teamwork and an amazing collaborative effort. Looking forward to the next one 😉
Archaea Biology Vienna@archaea-vienna.bsky.social · 3mo agoWe are excited to share a new preprint from Dimitris Dalkidis that identifies the effects of inhibitors DMPP and ATU in ammonia-oxidizing archaea! #archaea "Common nitrification inhibitors exhibit varied physiological mechanisms on an ammonia-oxidizing microorganism" www.biorxiv.org/content/10.6...
We are excited to share a new preprint from Dimitris Dalkidis that identifies the effects of inhibitors DMPP and ATU in ammonia-oxidizing archaea! #archaea "Common nitrification inhibitors exhibit varied physiological mechanisms on an ammonia-oxidizing microorganism" www.biorxiv.org/content/10.6...
Do biofilms give an ecological advantage? Yes! A fantastic follow-up to our previous biofilm work in ammonia-oxidizing archaea: "Biofilm Lifestyle Drives Ecophysiological Niche Expansion in an Archaeal Soil Nitrifier" www.biorxiv.org/content/10.6... Congratulations to all authors! #archaea
Cultivating the Ancestors… in Motion What electron microscope images hint at, but can only be seen in videos: how 'Asgard' archaea move.
Cultivating the Ancestors… in Motion
What electron microscope images hint at, but can only be seen in videos: how 'Asgard' archaea move.
smallthingsconsidered.blog
Slow and steady! After 15 years of continuous cultivation, we finally isolated the first psychrotolerant ammonia-oxidizing archaeon (AOA) from an arctic environment, Ca. Nitrosocosmicus articus! Our new article in Frontiers in Microbiology: doi.org/10.3389/fmic...
Article in TIME, featuring ISTA postdoc @eliamascolo.bsky.social. After 4 years in the US, he moved to Austria with the APART-USA fellowship, a program that supports outstanding researchers in relocating their work to Austria. 🔗 https://time.com/7379376/scientist-migration-us-to-europe/
I am super happy and honored to see some of my movies making it into the NYT. I hope everybody enjoys watching them go as much as I do!
Carl Zimmer@carlzimmer.com · 6mo agoScientists 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)
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)
Beyond thrilled to share that our study has been published! This project encompasses years of work, including my thesis research on Asgard archaea in the @archaeal.bsky.social lab at @utmsi.bsky.social and @texasscience.bsky.social!!! #MicroSky #ArchaeaSky 1/12
We are happy to share our newest preprint on a novel strain of Ca. Lokiarchaeum ossiferum, that contains an active provirus, capable of excision and independent replication! We propose a novel virus family: Fylgjaviridae. www.biorxiv.org/content/10.6...
biorxiv.org
Active virus-host system in a Lokiarchaeon culture | bioRxiv https://www.biorxiv.org/content/10.64898/2026.02.13.705702v1?rss=1
Active virus-host system in a Lokiarchaeon culture
Asgard archaea are considered the closest prokaryotic relatives of eukaryotes and having a crucial role in eukaryogenesis. Only few organisms have been cultivated from this group and their viruses were previously described only through metagenomic reconstructions. Here, we report the first successful cultivation of an Asgard archaeal virus infecting a novel strain of Ca. Lokiarchaeum ossiferum B36. The 16 kbp integrated provirus is capable to excise and replicate independently leading to the formation of virus particles. Network analysis of shared protein clusters with other archaeal viruses places it in a new family, Fylgjaviridae . The host encodes a distinctive repertoire of antiviral defense systems, including Septu, Wadjet, and type II CBASS system, all different from the defense systems of the related strain Ca. L. ossiferum B35. Our cultures provide the first opportunity to study interactions of a virus-host system in Asgards and hold significant potential for developing genetic tools. ### Competing Interest Statement The authors have declared no competing interest. FWF Austrian Science Fund, 10.55776/EFP25, Z437 European Research Council, Advanced Grant #695192: TACKLE Max Planck Society, https://ror.org/01hhn8329
biorxiv.org
Our latest preprint: Together with the team of Jan Löwe, @danieltamarit.bsky.social and many others we discovered and characterized several Asgard tubulin genes and propose that microtubule architecture and dynamics evolved in Asgard archaea prior to eukaryogenesis www.biorxiv.org/content/10.6...
DAY 243 SPECIES 243 - Ca. Lokiarchaeum ossiferum STAGE: Archaea MEDIUM: Arches Paper. Chromatek watercolor. Sakura pen NOTES: Yesterday was 10% shading and 90% painting, Todays was 90% shading with a 10min paint job. Looked better before painting, but I'll spend some more time on later archaea.
The origin of eukaryotic cells continues to be one of the greatest mysteries in biology. EMBL Grenoble is excited to welcome Florian Wollweber, who will use cutting-edge imaging techniques to study Asgard archaea — microbes closely related to our earliest ancestors. 🦠🔬 www.embl.org/news/people-...
#LivingArchitectures We put cells and cytoskeleton filaments on the architecture of the musée d'Orsay. www.musee-orsay.fr/fr/agenda/ev... Scientists of the #CytoMorphoLab adapted their protocols to illustrate the questions that keep them awake at night. -> Two shows on the 24th and 25th of January.
How did eukaryotic cells with complex architecture evolve from simpler prokaryotic cells? DNA analyses offer possible answers go.nature.com/4sEMwLH
Genomic clues to the origin of eukaryotic cells
How did eukaryotic cells with complex architecture evolve from simpler prokaryotic cells? DNA analyses offer possible answers.
go.nature.com
1. As we recently joined BlueSky, we want to repost this story for all newcomers! We sat down with @radler92.bsky.social to get more insight into the unique videos from his recent preprint on Promethearchaeota (formerly Asgard archaea). doi.org/10.1101/2025... (Videos and info below)
Dynamic protrusions mediate unique crawling motility in Asgard Archaea (Promethearchaeota)
Crawling motility is a hallmark of eukaryotic cells and requires a dynamic actin cytoskeleton, regulated adhesion, and spatially organized signalling pathways1–3. Asgard archaea (phylum Promethearchae...
doi.org
Are you a long-time fan of Archaea, an extremophile-phile, or are you simply curious? Either way, we have good news. We’re delighted to announce the 2026 EMBO Workshop on Archaea, 6–10 July. Sign up: meetings.embo.org/event/26-arc... We look forward to seeing you in Cambridge, UK. Please repost!
Molecular Biology of Archaea: Life Through the Prism of Archaea
In 1977, Woese and colleagues revealed Archaea as a distinct domain of life. Building on this insight, the discovery of Asgard archaea has strengthened the view that many hallmarks of eukaryotic cell…
meetings.embo.org
Fresh from our group, a new role for oxygen production in ammonia-oxidizing archaea: Oxygen production as an electron overflow pathway in ammonia-oxidizing archaea Congrats to Thomas Pribasnig for this great work! Check it out here: www.biorxiv.org/content/10.6...
And ‘Searching for the Asgards’ the movie: www.youtube.com/watch?v=mgmE...
Collaboration for Understanding | Searching for the Asgards
YouTube video by Schmidt Ocean
youtube.com
Asgard on the move ! Watch our videos! Biorxiv.org/content/10.1101/2025.11.30.690169v1
Dynamic protrusions mediate unique crawling motility in Asgard Archaea (Promethearchaeota)
Crawling motility is a hallmark of eukaryotic cells and requires a dynamic actin cytoskeleton, regulated adhesion, and spatially organized signalling pathways1–3. Asgard archaea (phylum Promethearchae...
biorxiv.org
