9CQR

Human metHb (C2 symmetry) obtained using the SPT Labtech chameleon under Al's Oil

9CQR の概要

• エントリーDOI: 10.2210/pdb9cqr/pdb
• EMDBエントリー: 45820
• 分子名称: Hemoglobin subunit alpha, Hemoglobin subunit beta, PROTOPORPHYRIN IX CONTAINING FE (3 entities in total)
• 機能のキーワード: hemoglobin, anaerobic, oxygen, heme, oxygen binding
• 由来する生物種: Homo sapiens (human); 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 64232.66

構造登録者

Cook, B.D.,Narehood, S.M.,McGuire, K.L.,Li, Y.,Tezcan, F.A.,Herzik, M.A. (登録日: 2024-07-19, 公開日: 2025-04-30)

主引用文献

Cook, B.D.,Narehood, S.M.,McGuire, K.L.,Li, Y.,Akif Tezcan, F.,Herzik Jr., M.A.
Preparation of oxygen-sensitive proteins for high-resolution cryoEM structure determination using blot-free vitrification.
Nat Commun, 16:3528-3528, 2025

PubMed Abstract: High-quality grid preparation for single-particle cryogenic electron microscopy (cryoEM) remains a bottleneck for routinely obtaining high-resolution structures. The issues that arise from traditional grid preparation workflows are particularly exacerbated for oxygen-sensitive proteins, including metalloproteins, whereby oxygen-induced damage and alteration of oxidation states can result in protein inactivation, denaturation, and/or aggregation. Indeed, 99% of the current structures in the EMBD were prepared aerobically and limited successes for anaerobic cryoEM grid preparation exist. Current practices for anaerobic grid preparation involve a vitrification device located in an anoxic chamber, which presents significant challenges including temperature and humidity control, optimization of freezing conditions, costs for purchase and operation, as well as accessibility. Here, we present a streamlined approach that allows for the vitrification of oxygen-sensitive proteins in reduced states using an automated blot-free grid vitrification device - the SPT Labtech chameleon. This robust workflow allows for high-resolution structure determination of dynamic, oxygen-sensitive proteins, of varying complexity and molecular weight.

PubMed: 40229244
DOI: 10.1038/s41467-025-58243-1

実験手法

ELECTRON MICROSCOPY (2.7 Å)