Marcin J. Suskiewicz
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msuskiewicz.bsky.social
Marcin J. Suskiewicz
@msuskiewicz.bsky.social
Structural biologist and biochemist. CNRS researcher at CBM Orléans @cbm-upr4301.bsky.social. Interested in protein modifications & interactions. Also husband, dad of 2, friend, ☧. Personal website: msuskiewicz.github.io
Compare panels a and c in figure above.
November 24, 2025 at 11:24 AM
Thank you! Yes, we had 2 types of samples, fl & slightly truncated, and we personally mostly worked with the latter, which gave a bit lower quality dataset. Also, helical reconstr. didn't work well, so we did 'single partcl' reconstr. of a filament fragment and then foc. ref. of a minimal element.
November 18, 2025 at 2:05 PM
That's very generous of you. Thanks so much @audeber.bsky.social
November 17, 2025 at 5:30 PM
I thank also our great labs @cbm-upr4301.bsky.social,
@dunnschool.bsky.social, @igdrennes.bsky.social, @pasteur.fr, & funding sources including @agencerecherche.bsky.social, @erc.europa.eu, @wellcometrust.bsky.social, and @natsmb.nature.com for very constructive revision. I'm sorry if forgetting sb.
November 17, 2025 at 2:34 PM
I'd also like to highlight a recent publication by @audeber.bsky.social, @enzopoirier.bsky.social, and colleagues showing FAM118B, which they term "SIRal", is essential for innate immune response in mammalian cellular models; they also have great phylogenetic analysis and insights into biochemistry.
A human homolog of SIR2 antiphage proteins mediates immunity via the Toll-like receptor pathway
Key actors of mammalian immunity originated from bacterial antiphage systems. The full extent of immune system conservation between bacteria and eukaryotes is unknown. Here, we show that the silent in...
www.science.org
November 17, 2025 at 2:16 PM
FAM118s have long interested Ivan (my postdoc PI), who, like in many other cases, had a good intuition about their importance. They have been a difficult biochemical target, though. We brought in the observation that they homooligomerise into filaments, an insight explored collaboratively here.
November 17, 2025 at 12:05 PM
I also highlight Andreja for her phylogenetic analysis, Karishma for NAD processing assays, and above all Ivan for his intuition, energy, and generosity. But all authors really!
November 17, 2025 at 12:04 PM
It was a close collab. with @ahellab.bsky.social, @spartelab.bsky.social, and other teams. All authors were important, but I'd like to highlight Domagoj Baretić and Sophia Missoury (with Franck Coste) for their cryoEM & other assays, and Sebastien Huet and his team for their great optical assays.
November 17, 2025 at 11:44 AM
In brief, we show that human FAM118s are closer to ancestral bacterial sirtuins than to canonical human SIRTs; that they assemble into filaments in vitro and in cells; that they have NAD processing (likely NAD-hydrolysis) activity; and that mixing two paralogues, FAM118B & FAM118A, boosts activity.
November 17, 2025 at 11:41 AM
The 7 canonical human sirtuins, SIRT1-SIRT7, are well studied enzymes associated with protein deacetylation activity. However, humans have 2 more poorly characterised sirtuin-fold proteins - FAM118B and FAM118A. Here, we study their evolution, structure, and molecular function.
November 17, 2025 at 11:39 AM