9O17

Cryo-EM structure of Methanosarcina acetivorans 70S ribosome

これはPDB形式変換不可エントリーです。

9O17 の概要

• エントリーDOI: 10.2210/pdb9o17/pdb
• EMDBエントリー: 49998
• 分子名称: 16S rRNA, Small ribosomal subunit protein eS8, Small ribosomal subunit protein uS9, ... (60 entities in total)
• 機能のキーワード: archaea, methanosarcina acetivorans, 70s ribosome, ribosome
• 由来する生物種: Methanosarcina acetivorans; 詳細
• タンパク質・核酸の鎖数: 58
• 化学式量合計: 2311797.41

構造登録者

Ghosh, A.,Fordjour, G.N.R.,Armache, J.-P.,Ferry, J.G.,Murakami, K.S.,Bevilacqua, P.C. (登録日: 2025-04-03, 公開日: 2025-09-24, 最終更新日: 2025-11-05)

主引用文献

Fordjour, G.N.R.,Ghosh, A.,Ferry, J.G.,Armache, J.P.,Bevilacqua, P.C.,Murakami, K.S.
Cryo-EM study and in vivo chemical mapping of the Methanosarcina acetivorans ribosome and its dimerization via a repurposed enzyme and translation factor.
J.Biol.Chem., 301:110686-110686, 2025

PubMed Abstract: Despite the overall conservation of ribosomes across all domains of life, differences in their 3D architecture, rRNA sequences, ribosomal protein composition, and translation factor requirements reflect lineage-specific adaptations to environmental niches. In the domain Archaea, structural studies have primarily focused on nonmethanogenic thermophiles and halophiles, leaving it unclear whether these represent the broader Archaea domain. Here, we report the cryo-electron microscopy (cryo-EM) structure of the ribosome from Methanosarcina acetivorans, a previously unreported high-resolution structure from a model mesophilic methanogenic archaeon. Compared to ribosomes from extremophiles, the M. acetivorans ribosome has a simplified architecture, lacking paralogous duplications and containing a reduced complement of ribosomal proteins. Structures of the large subunit (50S) from cells grown with either methanol or acetate show conserved rRNA folding and protein composition. High-resolution structures of the 50S subunit from the two growth substrates enabled us to investigate structural properties that may influence in vivo dimethyl sulfate reactivity, an orthogonal chemical approach used to probe RNA structure. We observed good agreement between in vivo dimethyl sulfate reactivity and ribosome structure. Finally, we identify a previously uncharacterized ribosome dimerization mode involving only 50S subunits and mediated by a heterotetrameric complex of PurH and aEF2-proteins with alternative metabolic and translational roles. This macromolecular assembly, which we term the methanogen ribosome dimerization factor, likely mediates ribosome hibernation, revealing an alternative regulatory mechanism in translation.

PubMed: 40914243
DOI: 10.1016/j.jbc.2025.110686

実験手法

ELECTRON MICROSCOPY (2.92 Å)