7XAM

Mycobacterium smegmatis 50S ribosomal subunit from Stationary phase of growth

7XAM の概要

• エントリーDOI: 10.2210/pdb7xam/pdb
• EMDBエントリー: 33096
• 分子名称: 50S ribosomal protein bL37, 50S ribosomal protein L10, 50S ribosomal protein L11, ... (36 entities in total)
• 機能のキーワード: 50s subunit, domain iv of 23s rrna, alternate conformation, helix 68, ribosome
• 由来する生物種: Mycolicibacterium smegmatis MC2 155; 詳細
• タンパク質・核酸の鎖数: 34
• 化学式量合計: 1495737.57

構造登録者

Sengupta, J.,Baid, P. (登録日: 2022-03-18, 公開日: 2023-05-03, 最終更新日: 2024-05-15)

主引用文献

Baid, P.,Sengupta, J.
Cryo-EM captures a unique conformational rearrangement in 23S rRNA helices of the Mycobacterium 50S subunit.
Int.J.Biol.Macromol., 253:126876-126876, 2023

PubMed Abstract: Structural investigations of the ribosomes isolated from pathogenic and non-pathogenic Mycobacterium species have identified several mycobacteria-specific structural features of ribosomal RNA and proteins. Here, we report structural evidence of a hitherto unknown conformational switch of mycobacterium 23S rRNA helices (H54a and H67-H71). Cryo-electron microscopy (cryo-EM) structures (~3-4 Å) of the M. smegmatis (Msm) log-phase 50S ribosomal subunit revealed conformational variability in H67-H71 region of the 23S rRNA, and manifested that, while H68 possesses the usual stretched conformation in one class of the maps, another one exhibits a bulge-out, fused density of H68-H69 at the inter-subunit surface, indicating an intrinsic dynamics of these rRNA helices. Remarkably, altered conformation of H68 forming a more prominent bulge-out structure at the inter-subunit surface of the 50S subunit due to the conformational rearrangements of 23S rRNA H67-H71 region was clearly visualized in a 3 Å cryo-EM map of the 50S subunit obtained from the stationary phase ribosome dataset. The Msm50S subunit having such bulge-out conformation at the intersubunit surface would be incompatible for associating with the 30S subunit due to its inability to form major inter-subunit bridges. Evidently, availability of active 70S ribosome pool can be modulated by stabilizing either one of the H68 conformation.

PubMed: 37709237
DOI: 10.1016/j.ijbiomac.2023.126876

実験手法

ELECTRON MICROSCOPY (3.5 Å)