New, very exciting preprint where we identify polycyclic triterpenoids lipids in archaea (Asgards) for the first time. This was a wonderful collaboration with Paula Welander’s lab.
https://www.biorxiv.org/content/10.1101/2025.02.07.637177v1
Eukaryotic membranes have polycyclic triterpenoids (mainly sterols) that are essential for a variety of cellular functions, but these have not been seen in archaea. So we searched for them in Asgard archaea, this revealed biosynthetic pathways for them.
The cyclases in this pathways are ancestral to a dipternoind, present in modern plants! Heterologous expression of them revealed they cyclize geranylgeranyl pyrophosphate to form bicyclic halimadienyl pyrophosphate. 
Only other prokaryotes that produce this compound are, Mycobacteria tuberculosis, that use it to mediate intracellular persistence in host endosomes during infection! Given that Asgard have a variety of genes for membrane trafficking we believe these have similar roles in Asgards
