Search results
Results From The WOW.Com Content Network
FAD is an aromatic ring system, whereas FADH 2 is not. [12] This means that FADH 2 is significantly higher in energy, without the stabilization through resonance that the aromatic structure provides. FADH 2 is an energy-carrying molecule, because, once oxidized it regains aromaticity and releases the energy represented by this stabilization.
NADH and FADH 2 are produced in the matrix or transported in through porin and transport proteins in order to undergo oxidation through oxidative phosphorylation. [1] NADH and FADH 2 undergo oxidation in the electron transport chain by transferring an electrons to regenerate NAD + and FAD.
Fl ox + Fl red H 2 ⇌ FlH • where Fl ox is the oxidized flavin, Fl red H 2 the reduced flavin (upon addition of two hydrogen atoms) and FlH • the semiquinone form (addition of one hydrogen atom). In the form of FADH 2, it is one of the cofactors that can transfer electrons to the electron transfer chain.
[2] A long-chain fatty acid is dehydrogenated to create a trans double bond between C2 and C3. This is catalyzed by acyl CoA dehydrogenase to produce trans-delta 2-enoyl CoA. It uses FAD as an electron acceptor and it is reduced to FADH 2. Trans-delta 2-enoyl CoA is hydrated at the double bond to produce L-3-hydroxyacyl CoA by enoyl-CoA hydratase.
1 FADH 2 : 6 H + : 6/4 ATP = 1 FADH 2 : 1.5 ATP. ATP : NADH+H + coming from glycolysis ratio during the oxidative phosphorylation is 1.5, as for FADH 2, if hydrogen atoms (2H + +2e −) are transferred from cytosolic NADH+H + to mitochondrial FAD by the glycerol phosphate shuttle located in the inner mitochondrial membrane.
The dihydrolipoate, covalently bound to a lysine residue of the complex, is then transferred to the Dihydrolipoyl dehydrogenase (E3) active site, [1] where it undergoes a flavin-mediated oxidation, similar in chemistry to e.g. thioredoxin reductase. First, FAD oxidizes dihydrolipoate back to its lipoate (disulfide) resting state, producing FADH 2.
Oxaloacetate + 2 H + + 2 e − → Malate -0.17 [ 10 ] While under standard conditions malate cannot reduce the more electronegative NAD + :NADH couple, in the cell the concentration of oxaloacetate is kept low enough that Malate dehydrogenase can reduce NAD + to NADH during the citric acid cycle .
FAD is a unique electron acceptor. Its fully reduced form is FADH 2 (known as the hydroquinone form), but FAD can also be partially oxidized as FADH by either reducing FAD or oxidizing FADH 2. [11] Dehydrogenases typically fully reduce FAD to FADH 2. The production of FADH is rare.