Krebs cycle (citric acid cycle; tricarboxylic acid cycle) (TCA cycle (also: CAC))

The Krebs (citric acid, TCA) cycle is an eight‑step mitochondrial pathway that oxidizes acetyl‑CoA to CO2, producing reducing equivalents (NADH, FADH2) and GTP/ATP that feed the electron transport chain for ATP synthesis; it is localized mainly in the mitochondrial matrix, with succinate dehydrogenase in the inner membrane. It is a central amphibolic hub supplying intermediates (e.g., citrate, α‑ketoglutarate, succinate, fumarate, malate, oxaloacetate) for biosynthetic and catabolic processes, and its intermediates are replenished (anaplerosis) or removed (cataplerosis) to match cellular demands. Dysregulation and enzyme mutations (e.g., IDH, SDH, FH) are implicated in cancer and other diseases, making specific TCA enzymes drug targets, even though “Krebs cycle activity” itself is a pathway‑level concept rather than a single therapeutic target.

Other names

Citric acid cycleTricarboxylic acid cycleTCA cycleCACKrebs cycle

Inhibition of mutant IDH to reduce oncometabolite 2‑hydroxyglutarate and restore cellular metabolism/epigenetic regulation in cancers