The chemical reactions and pathways resulting in the formation of creatine, N--N-methylglycine. Creatine is formed by a process beginning with amidino group transfer from L-arginine to glycine to form guanidinoacetate, followed by methyl group transfer from S-adenosyl-L-methionine to guanidinoacetate; it is then is phosphorylated to form a pool that stores high energy phosphate for the replenishment of ATP during periods of high, or fluctuating energy demand. In animals, most creatine is transported to and used in muscle.
creatine synthesis