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H₂O₂ selectively damages the binuclear iron-sulfur cluster N1b of respiratory complex I.

ABSTRACT: NADH:ubiquinone oxidoreductase, respiratory complex I, plays a major role in cellular energy metabolism by coupling electron transfer with proton translocation. Electron transfer is catalyzed by a flavin mononucleotide and a series of iron-sulfur (Fe/S) clusters. As a by-product of the reaction, the reduced flavin generates reactive oxygen species (ROS). It was suggested that the ROS generated by the respiratory chain in general could damage the Fe/S clusters of the complex. Here, we show that the binuclear Fe/S cluster N1b is specifically damaged by H₂O₂, however, only at high concentrations. But under the same conditions, the activity of the complex is hardly affected, since N1b can be easily bypassed during electron transfer.

SUBMITTER: Strotmann L

PROVIDER: S-EPMC10175503 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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H<sub>2</sub>O<sub>2</sub> selectively damages the binuclear iron-sulfur cluster N1b of respiratory complex I.

Strotmann Lisa L Harter Caroline C Gerasimova Tatjana T Ritter Kevin K Jessen Henning J HJ Wohlwend Daniel D Friedrich Thorsten T

Scientific reports 20230511 1

NADH:ubiquinone oxidoreductase, respiratory complex I, plays a major role in cellular energy metabolism by coupling electron transfer with proton translocation. Electron transfer is catalyzed by a flavin mononucleotide and a series of iron-sulfur (Fe/S) clusters. As a by-product of the reaction, the reduced flavin generates reactive oxygen species (ROS). It was suggested that the ROS generated by the respiratory chain in general could damage the Fe/S clusters of the complex. Here, we show that t ...[more]

PMID: 37169846

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