8OH5

Cryo-EM structure of the electron bifurcating transhydrogenase StnABC complex from Sporomusa Ovata (state 2)

8OH5 の概要

• エントリーDOI: 10.2210/pdb8oh5/pdb
• EMDBエントリー: 16878
• 分子名称: NAD-dependent formate dehydrogenase gamma subunit, NADPH DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE, NAD-reducing hydrogenase subunit HoxF, ... (10 entities in total)
• 機能のキーワード: flavin based electron-bifurcation, transhydrogenases, anaerobic metabolism, electron transport
• 由来する生物種: Sporomusa ovata DSM 2662; 詳細
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 861760.94

構造登録者

Kumar, A.,Kremp, F.,Mueller, V.,Schuller, J.M. (登録日: 2023-03-20, 公開日: 2023-09-13, 最終更新日: 2025-10-01)

主引用文献

Kumar, A.,Kremp, F.,Roth, J.,Freibert, S.A.,Muller, V.,Schuller, J.M.
Molecular architecture and electron transfer pathway of the Stn family transhydrogenase.
Nat Commun, 14:5484-5484, 2023

PubMed Abstract: The challenge of endergonic reduction of NADP using NADH is overcome by ferredoxin-dependent transhydrogenases that employ electron bifurcation for electron carrier adjustments in the ancient Wood-Ljungdahl pathway. Recently, an electron-bifurcating transhydrogenase with subunit compositions distinct from the well-characterized Nfn-type transhydrogenase was described: the Stn complex. Here, we present the single-particle cryo-EM structure of the Stn family transhydrogenase from the acetogenic bacterium Sporomusa ovata and functionally dissect its electron transfer pathway. Stn forms a tetramer consisting of functional heterotrimeric StnABC complexes. Our findings demonstrate that the StnAB subunits assume the structural and functional role of a bifurcating module, homologous to the HydBC core of the electron-bifurcating HydABC complex. Moreover, StnC contains a NuoG-like domain and a GltD-like NADPH binding domain that resembles the NfnB subunit of the NfnAB complex. However, in contrast to NfnB, StnC lost the ability to bifurcate electrons. Structural comparison allows us to describe how the same fold on one hand evolved bifurcation activity on its own while on the other hand combined with an associated bifurcating module, exemplifying modular evolution in anaerobic metabolism to produce activities critical for survival at the thermodynamic limit of life.

PubMed: 37673911
DOI: 10.1038/s41467-023-41212-x

実験手法

ELECTRON MICROSCOPY (3 Å)