Beckmann Lab

We are excited to share our collab with @kedrov-lab.bsky.social! Using Cryo-EM❄️ on an amazing sample, we found that YidC is recruited to the back of SecYEG during late-stage substrate insertion —supporting that the "back-of-Sec" route observed in eukaryotes also exists in bacteria 🦠. Check it out👇👇👇

Substrate-induced assembly and functional mechanism of the bacterial membrane protein insertase SecYEG-YidC The universally conserved Sec translocon and the YidC/Oxa1-type insertases mediate biogenesis of alpha-helical membrane proteins, but the molecular basis of their cooperation has remained disputed over decades. A recent discovery of a multi-subunit insertase in eukaryotes has raised the question about the architecture of the putative bacterial ortholog SecYEG-YidC and its functional mechanism. Here, we combine cryogenic electron microscopy with cell-free protein synthesis in nanodiscs to visualize biogenesis of the polytopic membrane protein NuoK, the subunit K of NADH-quinone oxidoreductase, that requires both SecYEG and YidC for insertion. We demonstrate that YidC is recruited to the back of the translocon at the late stage of the substrate insertion, in resemblance to the eukaryotic system, and in vivo experiments indicate that the complex assembly is vital for the cells. The nascent chain does not utilize the lateral gate of SecYEG, but enters the lipid membrane at the SecYE-YidC interface, with YidC being the primary insertase. SecYEG-YidC complex promotes folding of the nascent helices at the interface prior their insertion, so the examined cellular pathway follows the fundamental thermodynamic principles of membrane protein folding. Our data provide the first detailed insight on the elusive insertase machinery in the physiologically relevant environment, highlight the importance of the nascent chain for its assembly, and prove the evolutionary conservation of the gate-independent insertion route. ### Competing Interest Statement The authors have declared no competing interest. Deutsche Forschungsgemeinschaft, https://ror.org/018mejw64, Ke1879/3, 267205415 (CRC 1208) European Research Council, https://ror.org/0472cxd90, CRYOTRANSLATION

Very special feelings to announce this one... A project that started like 10 years ago is reaching the finish line, ready to shine. In a dream-team with @beckmannlab.bsky.social we solved the long-chased structure of the active membrane protein insertase SecYEG-YidC
www.biorxiv.org/content/10.1...

H/ACA snR30 snoRNP guides independent 18S rRNA subdomain formation - Nature Communications During synthesis, modification and maturation of the ribosomal RNA, correct subdomain folding without additional guidance poses a major challenge. Here, the authors observe the snR30 H/ACA snoRNP form...

Our results finally explain the essential role of snR30 snoRNA! Check out the details in www.nature.com/articles/s41...

We are happy to share that our snR30 story is finally out in @natureportfolio.nature.com 🥳 We report the first structure of a H/ACA snoRNP acting in ribosome synthesis thereby providing a detailed structural and biochemical view of the snR30 snoRNP guiding local 18S rRNA subdomain folding. 👇👇👇

How does an unusual heptameric AAA-ATPase translocate fully-folded Rieske protein across the inner mitochondrial membrane?
Cryo-EM & functional data by Roland Beckmann and coworkers show how Bcs1 alternates between different states during its translocation activity.
www.embopress.org/doi/full/10....