Quinone chemistry in respiratory complex I involves protonation of a conserved aspartic acid residue.

Autor: Harter C; Institut für Biochemie, Albert-Ludwigs-Universität Freiburg, Germany., Melin F; Laboratoire de Bioélectrochimie et Spectroscopie, UMR 7140, CMC, Université de Strasbourg CNRS, Strasbourg, France., Hoeser F; Institut für Biochemie, Albert-Ludwigs-Universität Freiburg, Germany., Hellwig P; Laboratoire de Bioélectrochimie et Spectroscopie, UMR 7140, CMC, Université de Strasbourg CNRS, Strasbourg, France.; Institut Universitaire de France (IUF), Paris, France., Wohlwend D; Institut für Biochemie, Albert-Ludwigs-Universität Freiburg, Germany., Friedrich T; Institut für Biochemie, Albert-Ludwigs-Universität Freiburg, Germany.
Jazyk: angličtina
Zdroj: FEBS letters [FEBS Lett] 2024 Sep 11. Date of Electronic Publication: 2024 Sep 11.
DOI: 10.1002/1873-3468.15013
Abstrakt: Respiratory complex I is a central metabolic enzyme coupling NADH oxidation and quinone reduction with proton translocation. Despite the knowledge of the structure of the complex, the coupling of both processes is not entirely understood. Here, we use a combination of site-directed mutagenesis, biochemical assays, and redox-induced FTIR spectroscopy to demonstrate that the quinone chemistry includes the protonation and deprotonation of a specific, conserved aspartic acid residue in the quinone binding site (D325 on subunit NuoCD in Escherichia coli). Our experimental data support a proposal derived from theoretical considerations that deprotonation of this residue is involved in triggering proton translocation in respiratory complex I.
(© 2024 The Author(s). FEBS Letters published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)
Databáze: MEDLINE
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