PuSH - Publikationsserver des Helmholtz Zentrums München

Kumar, A.* ; Roth, J.* ; Kim, H.* ; Saura, P.* ; Bohn, S. ; Reif-Trauttmansdorff, T.* ; Schubert, A.* ; Kaila, V.R.I.* ; Schuller, J.M.* ; Müller, V.*

Molecular principles of redox-coupled sodium pumping of the ancient Rnf machinery.

Nat. Commun. 16:2302 (2025)
Verlagsversion DOI PMC
Open Access Gold
Creative Commons Lizenzvertrag
The Rnf complex is the primary respiratory enzyme of several anaerobic prokaryotes that transfers electrons from ferredoxin to NAD+ and pumps ions (Na+ or H+) across a membrane, powering ATP synthesis. Rnf is widespread in primordial organisms and the evolutionary predecessor of the Na+-pumping NADH-quinone oxidoreductase (Nqr). By running in reverse, Rnf uses the electrochemical ion gradient to drive ferredoxin reduction with NADH, providing low potential electrons for nitrogenases and CO2 reductases. Yet, the molecular principles that couple the long-range electron transfer to Na+ translocation remain elusive. Here, we resolve key functional states along the electron transfer pathway in the Na+-pumping Rnf complex from Acetobacterium woodii using redox-controlled cryo-electron microscopy that, in combination with biochemical functional assays and atomistic molecular simulations, provide key insight into the redox-driven Na+ pumping mechanism. We show that the reduction of the unique membrane-embedded [2Fe2S] cluster electrostatically attracts Na+, and in turn, triggers an inward/outward transition with alternating membrane access driving the Na+ pump and the reduction of NAD+. Our study unveils an ancient mechanism for redox-driven ion pumping, and provides key understanding of the fundamental principles governing energy conversion in biological systems.
Altmetric
Weitere Metriken?
Zusatzinfos bearbeiten [➜Einloggen]
Publikationstyp Artikel: Journalartikel
Dokumenttyp Wissenschaftlicher Artikel
Korrespondenzautor
Schlagwörter Rhodobacter-capsulatus; Acetobacterium-woodii; Nitrogen-fixation; Identification; Oxidoreductase; Quantitation; Transport; Model; Na+; Ion
ISSN (print) / ISBN 2041-1723
e-ISSN 2041-1723
Zeitschrift Nature Communications
Quellenangaben Band: 16, Heft: 1, Seiten: , Artikelnummer: 2302 Supplement: ,
Verlag Nature Publishing Group
Verlagsort London
Nichtpatentliteratur Publikationen
Begutachtungsstatus Peer reviewed
Förderungen Leibniz-Rechenzentrum (LRZ)
DFG
European Union
German Research Foundation (DFG)
European Research Council under the European Union
Swedish Research Council
Knut and Alice Wallenberg (KAW) Foundation
EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council)