Creatine biosynthesis pathway

The creatine biosynthesis pathway consists of a series of enzymatic reactions leading to the production of creatine from amino acids, mainly in the kidney and liver. The two main synthetic steps involve AGAT (L-arginine:glycine amidinotransferase) converting arginine and glycine to guanidinoacetate, followed by GAMT (guanidinoacetate methyltransferase) methylating guanidinoacetate to form creatine. The generated creatine is then transported, mainly to muscle and brain, where it is phosphorylated by creatine kinases to create phosphocreatine—a rapid reserve for ATP regeneration in tissues with high, fluctuating energy demands. Impairment of this pathway underlies rare genetic creatine deficiency syndromes characterized by neurological and muscular symptoms. Interventions such as creatine supplementation target the metabolic consequences (not the pathway directly), and the pathway's enzymes are occasionally considered therapeutic targets in specific contexts, rather than the pathway as a whole.

Other names

creatine synthetic pathway

Creatine supplementation increases intracellular creatine/phosphocreatine pools, buffering ATP supply in high-demand tissues. Modulators of the pathway can act by inhibiting or enhancing enzyme activity (e.g., AGAT or GAMT inhibition/deficiency causes disease).