In this section
If the results of the measurements performed at the PEPR Facility are included in a publication, the following statement shall be added to the Acknowledgments section: "The EPR measurements were performed at the Centre for Pulse EPR at Imperial College London (PEPR), supported by the EPSRC grant EP/T031425/1."
We would be grateful if the Facility could be informed of the submission by sending an e-mail to m.roessler@imperial.ac.uk and a.collauto@imperial.ac.uk.
@article{Hameedi:2021:10.1016/j.jbc.2021.100474,
author = {Hameedi, MA and Grba, DN and Richardson, KH and Jones, AJY and Song, W and Roessler, MM and Wright, JJ and Hirst, J},
doi = {10.1016/j.jbc.2021.100474},
journal = {Journal of Biological Chemistry},
title = {A conserved arginine residue is critical for stabilizing the N2 FeS cluster in mitochondrial complex I},
url = {http://dx.doi.org/10.1016/j.jbc.2021.100474},
volume = {296},
year = {2021}
}
TY - JOUR
AB - Respiratory complex I (NADH:ubiquinone oxidoreductase), the first enzyme of the electron-transport chain, captures the free energy released by NADH oxidation and ubiquinone reduction to translocate protons across an energy-transducing membrane and drive ATP synthesis during oxidative phosphorylation. The cofactor that transfers the electrons directly to ubiquinone is an iron-sulfur cluster (N2) located in the NDUFS2/NUCM subunit. A nearby arginine residue (R121), which forms part of the second coordination sphere of the N2 cluster, is known to be post-translationally dimethylated but its functional and structural significance are not known. Here, we show that mutations of this arginine residue (R121M/K) abolish the quinone-reductase activity, concomitant with disappearance of the N2 signature from the electron paramagnetic resonance (EPR) spectrum. Analysis of the cryo-EM structure of NDUFS2-R121M complex I at 3.7 Å resolution identified the absence of the cubane N2 cluster as the cause of the dysfunction, within an otherwise intact enzyme. The mutation further induced localised disorder in nearby elements of the quinone-binding site, consistent with the close connections between the cluster and substrate-binding regions. Our results demonstrate that R121 is required for the formation and/or stability of the N2 cluster, and highlight the importance of structural analyses for mechanistic interpretation of biochemical and spectroscopic data on complex I variants.
AU - Hameedi,MA
AU - Grba,DN
AU - Richardson,KH
AU - Jones,AJY
AU - Song,W
AU - Roessler,MM
AU - Wright,JJ
AU - Hirst,J
DO - 10.1016/j.jbc.2021.100474
PY - 2021///
SN - 0021-9258
TI - A conserved arginine residue is critical for stabilizing the N2 FeS cluster in mitochondrial complex I
T2 - Journal of Biological Chemistry
UR - http://dx.doi.org/10.1016/j.jbc.2021.100474
UR - https://www.ncbi.nlm.nih.gov/pubmed/33640456
UR - http://hdl.handle.net/10044/1/90253
VL - 296
ER -
Centre for Pulse EPR Spectroscopy
Department of Chemistry
Imperial College London
White City Campus
Molecular Sciences Research Hub
London W12 0BZ
E-mail: a.collauto@imperial.ac.uk
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