Spectral deconvolution of redox species in the crotonyl-CoA-dependent NADH:ferredoxin oxidoreductase from Megasphaera elsdenii. A flavin-dependent bifurcating enzyme.

Autor: Vigil W Jr; Department of Biochemistry, University of California, Riverside, Riverside, CA, 92521, USA., Niks D; Department of Biochemistry, University of California, Riverside, Riverside, CA, 92521, USA., Franz-Badur S; Department of Biochemistry, University of California, Riverside, Riverside, CA, 92521, USA., Chowdhury N; Max Planck Institute for Terrestrial Microbiology, Marburg, Germany., Buckel W; Max Planck Institute for Terrestrial Microbiology, Marburg, Germany; Fachbereich Biologie and Synmikro, Philipps-Universität, Marburg, Germany., Hille R; Department of Biochemistry, University of California, Riverside, Riverside, CA, 92521, USA. Electronic address: russ.hille@ucr.edu.
Jazyk: angličtina
Zdroj: Archives of biochemistry and biophysics [Arch Biochem Biophys] 2021 Apr 15; Vol. 701, pp. 108793. Date of Electronic Publication: 2021 Feb 12.
DOI: 10.1016/j.abb.2021.108793
Abstrakt: We have undertaken a spectral deconvolution of the three FADs of EtfAB/bcd to the spectral changes seen in the course of reduction, including the spectrally distinct anionic and neutral semiquinone states of electron-transferring and bcd flavins. We also demonstrate that, unlike similar systems, no charge-transfer complex is observed on titration of the reduced M. elsdenii EtfAB with NAD + . Finally, and significantly, we find that removal of the et FAD from EtfAB results in an uncrossing of the half-potentials of the bifurcating FAD that remains in the protein, as reflected in the accumulation of substantial FAD• - in the course of reductive titrations of the depleted EtfAB with sodium dithionite.
(Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
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