What does FADH2 primarily participate in during metabolism?

FADH2 primarily participates in single-electron transfer during metabolism, especially in the context of cellular respiration and the electron transport chain. It acts as an important electron carrier, derived from the oxidation of fatty acids and the citric acid cycle, and transfers electrons to complex II of the electron transport chain.

This transfer is important because it contributes to the generation of a proton gradient across the inner mitochondrial membrane. The energy from this gradient is ultimately used to produce ATP through oxidative phosphorylation via ATP synthase. FADH2 does not directly engage in processes such as direct signaling, protein synthesis, or nucleic acid formation, distinguishing its role specifically within the energy conversion pathways.