Template:Correction NAD and H+: Difference between revisions
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[[File:Ambiguity alert H+.png|left|80px]] | [[File:Ambiguity alert H+.png|left|80px]] | ||
:::: However, the current literature contains inconsistencies regarding H<sup>+</sup> formation on the negative side of bioenergetic membranes, such as the matrix side of the mitochondrial inner membrane, when NADH is oxidized during oxidative phosphorylation (OXPHOS). Ambiguities arise when examining the oxidation of NADH by respiratory Complex I or succinate by Complex II. | :::: However, the current literature contains inconsistencies regarding H<sup>+</sup> formation on the negative side of bioenergetic membranes, such as the matrix side of the mitochondrial inner membrane, when NADH is oxidized during oxidative phosphorylation (OXPHOS). Ambiguities arise when examining the oxidation of NADH by respiratory Complex I or succinate by Complex II. | ||
[[File:Ambiguity alert NAD.png|left| | [[File:Ambiguity alert NAD.png|left|60px]] | ||
:::: The oxidized NAD<sup>+</sup> is distinguished from NAD indicating nicotinamide adenine dinucleotide independent of oxidation state. | :::: The oxidized NAD<sup>+</sup> is distinguished from NAD indicating nicotinamide adenine dinucleotide independent of oxidation state. | ||
:::: NADH + H<sup>+</sup> → NAD<sup>+</sup> +2{H<sup>+</sup>+e<sup>-</sup>} is the oxidation half-reaction in this H<sup>+</sup>-linked electron transfer represented as 2{H<sup>+</sup>+e<sup>-</sup>} ([[Gnaiger 2023 MitoFit CII |Gnaiger 2023]]). Putative H<sup>+</sup> formation shown as NADH → NAD<sup>+</sup> + H<sup>+</sup> conflicts with chemiosmotic coupling stoichiometries between H<sup>+</sup> translocation across the coupling membrane and electron transfer to oxygen. Ensuring clarity in this complex field is imperative to tackle the apparent ambiguity crisis and prevent confusion, particularly in light of the increasing number of interdisciplinary publications on bioenergetics concerning diagnostic and clinical applications of OXPHOS analysis. | :::: NADH + H<sup>+</sup> → NAD<sup>+</sup> +2{H<sup>+</sup>+e<sup>-</sup>} is the oxidation half-reaction in this H<sup>+</sup>-linked electron transfer represented as 2{H<sup>+</sup>+e<sup>-</sup>} ([[Gnaiger 2023 MitoFit CII |Gnaiger 2023]]). Putative H<sup>+</sup> formation shown as NADH → NAD<sup>+</sup> + H<sup>+</sup> conflicts with chemiosmotic coupling stoichiometries between H<sup>+</sup> translocation across the coupling membrane and electron transfer to oxygen. Ensuring clarity in this complex field is imperative to tackle the apparent ambiguity crisis and prevent confusion, particularly in light of the increasing number of interdisciplinary publications on bioenergetics concerning diagnostic and clinical applications of OXPHOS analysis. | ||
[[Category:Ambiguity crisis - NAD and H+]] | [[Category:Ambiguity crisis - NAD and H+]] |
Revision as of 05:13, 17 October 2023
Hydrogen ion ambiguities in the electron transfer system
Communicated by Gnaiger E (2023-10-08) last update 2023-10-15
- Electron (e-) transfer linked to hydrogen ion (H+) transfer is a fundamental concept in the field of bioenergetics, critical for understanding redox-coupled energy transformations.
- However, the current literature contains inconsistencies regarding H+ formation on the negative side of bioenergetic membranes, such as the matrix side of the mitochondrial inner membrane, when NADH is oxidized during oxidative phosphorylation (OXPHOS). Ambiguities arise when examining the oxidation of NADH by respiratory Complex I or succinate by Complex II.
- The oxidized NAD+ is distinguished from NAD indicating nicotinamide adenine dinucleotide independent of oxidation state.
- NADH + H+ → NAD+ +2{H++e-} is the oxidation half-reaction in this H+-linked electron transfer represented as 2{H++e-} (Gnaiger 2023). Putative H+ formation shown as NADH → NAD+ + H+ conflicts with chemiosmotic coupling stoichiometries between H+ translocation across the coupling membrane and electron transfer to oxygen. Ensuring clarity in this complex field is imperative to tackle the apparent ambiguity crisis and prevent confusion, particularly in light of the increasing number of interdisciplinary publications on bioenergetics concerning diagnostic and clinical applications of OXPHOS analysis.