Debnath Ghosal

Thanks Ariane :-)

Indeed, thanks

Wonderful collaboration with Sigal Ben-Yehuda lab! Our PhD student Somavally Dalvi, who just had her superb thesis oration drove the high-resolution imaging part of the project.
@unimelb, @FMDHS, @ccemmp-outreach.bsky.social

In this system, bacteria detect phage infection through a sensor protein (YjbH) and respond by severing the infected part of the cell via aberrant division. The rest of the cell survives and continues growing happily, essentially, bacterial autotomy!

Just as doctors may amputate an infected limb to save a patient’s life, or lizards drop their tails to escape predators, despite being single-celled organisms, bacteria can do a similar escape act. How cool is that?

📣 New paper alert! Just out in Cell Reports! pubmed.ncbi.nlm.nih.gov/40644298/
Thrilled to share that we have discovered a brand-new anti-phage defense system! Bacteria have evolved various defense strategies (CRISPR etc) to counter phage attacks. We found a new one - fascinating and dramatic
⚔️🦠❄️🔬

Of course! Let’s catch up

Very interesting work!

Amazing structure and insights! Congratulations.

“Revolutionary Science Comes from Unexpected Angles”

Thoughts from our own Tom Rapoport on the role of basic science in curing disease. magazine.hms.harvard.edu/articles/rev...

Amazing insights!

Great team of grad students and post docs and led together with an awesome group of PIs @debnathghosal.bsky.social @kmichie.bsky.social @iduggin.bsky.social. As something different here be a cool AI-generated artistic impression of our #Asgards hanging in their microbial mat 'ancient home'....⚔️

Thanks much Harry!

Thanks Martin @pilhoferlab.bsky.social

Massive Team effort! Thanks to all for bringing this together! @brendanburns999.bsky.social
@iduggin.bsky.social @kmichie.bsky.social
@snobsi.bsky.social , @juliameltzer.bsky.social, @xabivc.bsky.social, @tiltedscientist.bsky.social @bindusmitapaul.bsky.social @dcshepherd.bsky.social and others.

This offers the first glimpse into how complex eukaryotic cells may have evolved from archaeal ancestors — one of the biggest open questions in biology.
As ‪@brendanburns999.bsky.social‬ says: “Stromatolites may represent the ‘microbial village’ that helped raise a eukaryote.” Exciting times ahead!

Popular theory of eukaryogenesis suggests an Asgard archaeon once engulfed a bacterium, giving rise to the first eukaryotic cell. The bacterium became the mitochondrion. We show direct physical interaction between an Asgard archaeon and a bacterium via nanotubes! Maybe that's how it all started? 👀

Our CryoET imaging revealed N. marumarumayae possesses unique cell features that appear to reflect their ancestry as progenitors for the earliest eukaryotic cells. ❄️🦠 🔬

Did we see any secrets of eukaryotic life in these organisms? Extensive genomic analysis revealed metabolic capacities and many eukaryotic signature proteins, including ESCRTs, Sec23/24-like proteins etc and some completely novel folds!

“Nerearchaeum” in Greek means 'Old Man of the Sea' and “marumarumayae”, derived from the Indigenous language of the Malgana people of Shark Bay, refers to ‘ancient home’.  Nerearchaeum marumarumayae means 'Old Man of the Sea' from the ‘ancient home’! Cool name, right?

In this study, we report ~ 90% (possibly highest to date!) enrichment of a new Asgard archaeon, “Nerearchaeum marumarumayae”, isolated from a microbial mat in Shark Bay, Australia, similar to what might’ve existed billions of years ago. Just the 4th member enriched from the Asgard superphylum!

Asgard archaea are among the most intriguing microbes on Earth. They’re the closest living relatives of eukaryotes and may hold secrets to how complex eukaryotic life evolved. BUT, they’re notoriously hard to enrich/ culture due to their exotic growth conditions and mysterious community ties.

An Asgard archaeon from a modern analog of ancient microbial mats It has been proposed that eukaryotic cells evolved via symbiosis between sulfate-reducing bacteria and hydrogen-producing archaea. Here we describe a highly enriched culture of a novel Asgard archaeon...

📣 New paper alert!
One of the most exciting projects we've done in recent years is now out on BioRxiv: "An Asgard archaeon from a modern analog of ancient microbial mats".

Glimpse into early complex life! ❄️🦠 🔬🧬

www.biorxiv.org/content/10.1.... A thread...

Thanks Ariane!

Many thanks, Oli!

Many moons later, in collaboration with Ramanujam Srinivasan’s group, we have now visualized (stabilized) ParA filaments in cells and identified the molecular basis of ParA polymerization. Nucleic Acids Research, 2025 academic.oup.com/nar/article/...

ParABS systems are designed machineries to perform this faithful segregation. ParA family of proteins are thought to form polymers that segregate plasmids. I extensively worked on these proteins during my PhD days and always wanted to visualize ParA oligomers in cells.

Bacteria often hide antibiotic resistant genes in small mobile genetic elements known as plasmids. Faithful segregation of these plasmids into daughter cells is essential for bacteria to continue resistance. They don’t just resist - they pass it on. 🦠💊

Massive congratulations, @dcshepherd.bsky.social! #ThesisOration #LabMilestone #ProudMoment #ResearchJourney

This marks a huge milestone for our lab, and we couldn’t be prouder of everything he has achieved. The story he’s putting together is nothing short of inspiring.