9F47

crystal structure of [FeFe]-hydrogenase CbA5H from Clostridium beijerinckii in Hinact state

9F47 の概要

• エントリーDOI: 10.2210/pdb9f47/pdb
• 関連するPDBエントリー: 6TTL
• 分子名称: [FeFe]-hydrogenase, dicarbonyl[bis(cyanide-kappaC)]-mu-(iminodimethanethiolatato-1kappaS:2kappaS)-mu-(oxomethylidene)diiron(2+), IRON/SULFUR CLUSTER, ... (6 entities in total)
• 機能のキーワード: [fefe]-hydrogenase, inactive state, clostridium beijerinckii, oxidoreductase
• 由来する生物種: Clostridium beijerinckii
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 153308.97

構造登録者

Duan, J.,Rutz, A.,Hofmann, E.,Happe, T.,Kurisu, G. (登録日: 2024-04-26, 公開日: 2024-12-18, 最終更新日: 2025-01-22)

主引用文献

Duan, J.,Rutz, A.,Kawamoto, A.,Naskar, S.,Edenharter, K.,Leimkuhler, S.,Hofmann, E.,Happe, T.,Kurisu, G.
Structural determinants of oxygen resistance and Zn 2+ -mediated stability of the [FeFe]-hydrogenase from Clostridium beijerinckii.
Proc.Natl.Acad.Sci.USA, 122:e2416233122-e2416233122, 2025

PubMed Abstract: [FeFe]-hydrogenases catalyze the reversible two-electron reduction of two protons to molecular hydrogen. Although these enzymes are among the most efficient H-converting biocatalysts in nature, their catalytic cofactor (termed H-cluster) is irreversibly destroyed upon contact with dioxygen. The [FeFe]-hydrogenase CbA5H from has a unique mechanism to protect the H-cluster from oxygen-induced degradation. The protective strategy of CbA5H was proposed based on a partial protein structure of CbA5H's oxygen-shielded form. Here, we present a cryo-EM structure of 2.2 Å resolution from the entire enzyme in its dimeric and active state and elucidate the structural parameters of the reversible cofactor protection mechanism. We found that both subunits of the homodimeric structure of CbA5H have a Zn-binding four-helix domain, which does not play a role in electron transport as described for other complex protein structures. Biochemical data instead confirm that two [4Fe-4S] clusters are responsible for electron transfer in CbA5H, while the identified zinc atom is critical for oligomerization and protein stability.

PubMed: 39805018
DOI: 10.1073/pnas.2416233122

実験手法

X-RAY DIFFRACTION (2.9 Å)