hydrogenated FAD

chemical compound

Also known as: FADH

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Last updated

June 29, 2026

Quick Summary

Hydrogenated FAD, also known as FADH₂, is a coenzyme crucial for cellular energy production. It is formed when FAD (flavin adenine dinucleotide) accepts hydrogen atoms or electrons during metabolic processes, particularly within mitochondria.1234

Hydrogenation is the chemical process of adding hydrogen to a molecule. In biological systems, FADH₂ acts as an electron donor in the respiratory chain, transferring these electrons to ultimately help generate ATP, the cell's energy currency. This process is a vital part of cellular respiration, enabling cells to extract energy from nutrients.524

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cell
Formation of the electron donors NADH and FADH2
…dinucleotide (FAD), yielding NADH and FADH₂. It is the subsequent oxidation of these hydrogen acceptors that leads eventually to the production of ATP.
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…dinucleotide (FAD), yielding NADH and FADH₂. It is the subsequent oxidation of these hydrogen acceptors that leads eventually to the production of ATP.
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lipid
Oxidation of fatty acids
…energy in the form of FADH₂ and NADH and a small amount of ATP. This process is carried out in a series of nine enzymatically catalyzed reactions in the mitochondrial matrix space. The reactions form a closed cycle, often called the citric acid, tricarboxylic acid, or Krebs cycle (after its…
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…energy in the form of FADH₂ and NADH and a small amount of ATP. This process is carried out in a series of nine enzymatically catalyzed reactions in the mitochondrial matrix space. The reactions form a closed cycle, often called the citric acid, tricarboxylic acid, or Krebs cycle (after its…
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plant
Principal pathways and cycles
… (FAD) to form NADH and FADH, respectively. The reduced coenzymes NADH and FADH enter into a sequence of reactions called the respiratory chain on the inner membrane of the mitochondrion. This chain is a series of carriers (ubiquinone and several iron-containing chemicals called cytochromes) that ultimately transfer the hydrogen and…
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… (FAD) to form NADH and FADH, respectively. The reduced coenzymes NADH and FADH enter into a sequence of reactions called the respiratory chain on the inner membrane of the mitochondrion. This chain is a series of carriers (ubiquinone and several iron-containing chemicals called cytochromes) that ultimately transfer the hydrogen and…
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