P/O ratio (ATP made per O atom reduced) for FADH2

Value 2 unitless
Organism Unspecified
Reference Denise R. Ferrier, Biochemistry (Lippincott Illustrated Reviews Series), 5th edition 2011 link p.77 heading "4"
Comments P.76 5th paragraph from top, heading "D": "Release of free energy during electron transport: Free energy is released as electrons are transferred along the electron transport chain from an electron donor (reducing agent or reductant) to an electron acceptor (oxidizing agent or oxidant). The electrons can be transferred as hydride ions (:H–) to NAD+, as hydrogen atoms (•H) to FMN (Flavin mononucleotide), coenzyme Q, and FAD (flavin adenine dinucleotide), or as electrons (e–) to cytochromes." P.77, 3rd paragraph from top, heading "4": "ΔGo of ATP: The standard free energy for the phosphorylation of ADP to ATP is +7.3 kcal/mol. The transport of a pair of electrons from NADH to oxygen via the electron transport chain produces 52.58 kcal. Therefore, more than sufficient energy is available to produce three ATP from three ADP and three Pi (3 x 7.3 = 21.9kcal/mol), sometimes expressed as a P:O ratio (ATP made per O atom reduced) of 3:1. The remaining calories are used for ancillary reactions or released as heat. [Note: P:O for FADH2 is 2:1 because Complex I is bypassed.]"
Entered by Uri M
ID 110629