Glycine amidinotransferase, mitochondrial (GATM)

Glycine amidinotransferase, mitochondrial (GATM), is a mitochondrial enzyme belonging to the amidinotransferase family and encoded by the GATM gene (chromosome 15q15.3). This enzyme catalyzes the first and rate-limiting step in creatine biosynthesis—transferring a guanidino group from arginine to glycine to form guanidinoacetate, which is then methylated to creatine. Creatine is essential for cellular energy storage and buffering, especially in tissues with high-energy demands such as muscle, brain, heart, and kidney. Deficiency in GATM causes serious metabolic disorders, including intellectual disability, developmental delay, and muscle weakness; these can sometimes be alleviated by creatine supplementation. Expression and activity of GATM are relevant to cardiovascular function, renal performance, and pharmacogenomic variability in response to statin therapy. GATM is thus a key enzyme at the intersection of energy metabolism, genetic disease, and drug response.

Other names

AGATL-arginine:glycine amidinotransferaseTransamidinaseCCDS3GATM_HUMANglycine amidinotransferase (L-arginine:glycine amidinotransferase)testicular secretory protein Li 19

Supplementation with creatine bypasses the GATM biosynthetic block in deficiency syndromes, improving neurological symptoms; Pharmacogenomic modulation (statin effects and adverse events, such as myopathy, may be modulated by GATM genetic variants/eQTLs)