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Incoming links: Coupled-enzyme readout of glycolytic ATP formation
Substrate-level phosphorylation Created 2026-10-14 Updated 2026-10-18
Substrate-level phosphorylation forms ATP by enzyme-catalyzed transfer of a phosphate group from a phosphorylated substrate to ADP. In canonical glycolysis, two such transfers occur for each three-carbon route, giving four gross ATP per glucose. Unlike oxidative phosphorylation, these transfers do not require an electron transport chain.[ref]
Biology 2e by Mary Ann Clark and others. §7.2, steps 7 and 10: phosphate transfer to ADP; §7.5, opening comparison of fermentation with respiration
The pyruvate kinase example under Coupled-enzyme readout of glycolytic ATP formation separates the material transfer from its detection. A favourable coupled chemical reaction supplies the driving change in Gibbs free energy; the enzyme supplies a catalytic route. Counting ATP-forming transfers gives a gross yield, while subtracting upstream ATP use gives the net yield.