Thiopurine methyltransferase or thiopurine S-methyltransferase (TPMT) is an enzyme that in humans is encoded by the TPMT gene. A pseudogene for this locus is located on chromosome 18q.
Trifunctional enzyme subunit beta, mitochondrial (TP-beta) also known as 3-ketoacyl-CoA thiolase, acetyl-CoA acyltransferase, or beta-ketothiolase is an enzyme that in humans is encoded by the HADHB gene.
Cystathionine-β-synthase, also known as CBS, is an enzyme (EC 4.2.1.22) that in humans is encoded by the CBS gene. It catalyzes the first step of the transsulfuration pathway, from homocysteine to cystathionine:
L-Arginine:glycine amidinotransferase is the enzyme that catalyses the transfer of an amidino group from L-arginine to glycine. The products are L-ornithine and glycocyamine, also known as guanidinoacetate, the immediate precursor of creatine. Creatine and its phosphorylated form play a central role in the energy metabolism of muscle and nerve tissues. Creatine is in highest concentrations in the skeletal muscle, heart, spermatozoa and photoreceptor cells. Creatine helps buffer the rapid changes in ADP/ATP ratio in muscle and nerve cells during active periods. Creatine is also synthesized in other tissues, such as pancreas, kidneys, and liver, where amidinotransferase is located in the cytoplasm, including the intermembrane space of the mitochondria, of the cells that make up those tissues.
N-Acetylserotonin O-methyltransferase, also known as ASMT, is an enzyme which catalyzes the final reaction in melatonin biosynthesis: converting Normelatonin to melatonin. This reaction is embedded in the more general tryptophan metabolism pathway. The enzyme also catalyzes a second reaction in tryptophan metabolism: the conversion of 5-hydroxy-indoleacetate to 5-methoxy-indoleacetate. The other enzyme which catalyzes this reaction is n-acetylserotonin-o-methyltransferase-like-protein.
Guanidinoacetate methyltransferase deficiency is an autosomal recessive cerebral creatine deficiency that primarily affects the nervous system and muscles. It is the first described disorder of creatine metabolism, and results from deficient activity of guanidinoacetate methyltransferase, an enzyme involved in the synthesis of creatine. Clinically, affected individuals often present with hypotonia, seizures and developmental delay. Diagnosis can be suspected on clinical findings, and confirmed by specific biochemical tests, brain magnetic resonance spectroscopy, or genetic testing. Biallelic pathogenic variants in GAMT are the underlying cause of the disorder. After GAMT deficiency is diagnosed, it can be treated by dietary adjustments, including supplementation with creatine. Treatment is highly effective if started early in life. If treatment is started late, it cannot reverse brain damage which has already taken place.
In enzymology, a mRNA (guanine-N7-)-methyltransferase also known as mRNA cap guanine-N7 methyltransferase is an enzyme that catalyzes the chemical reaction
Glucosamine—fructose-6-phosphate aminotransferase isomerizing 1 is an enzyme that in humans is encoded by the GFPT1 gene.
Glycine amidinotransferase, mitochondrial is an enzyme that in humans is encoded by the GATM gene.
Protein-L-isoaspartate(D-aspartate) O-methyltransferase is an enzyme that in humans is encoded by the PCMT1 gene.
Sodium- and chloride-dependent creatine transporter 1 is a protein that in humans is encoded by the SLC6A8 gene.
Nicotinamide N-methyltransferase (NNMT) is an enzyme that in humans is encoded by the NNMT gene. NNMT catalyzes the methylation of nicotinamide and similar compounds using the methyl donor S-adenosyl methionine (SAM-e) to produce S-adenosyl-L-homocysteine (SAH) and 1-methylnicotinamide.
Protein arginine N-methyltransferase 2 is an enzyme that in humans is encoded by the PRMT2 gene.
Solute carrier family 2, facilitated glucose transporter member 10 is a protein that in humans is encoded by the SLC2A10 gene.
D-2-hydroxyglutarate dehydrogenase, mitochondrial is an enzyme that in humans is encoded by the D2HGDH gene.
Putative ribosomal RNA methyltransferase 1 is an enzyme that in humans is encoded by the FTSJ1 gene.
Protein arginine N-methyltransferase 6 is an enzyme that in humans is encoded by the PRMT6 gene.
Uncharacterized methyltransferase WBSCR22 is an enzyme that in humans is encoded by the WBSCR22 gene.
Dihydropyrimidinase is an enzyme that in humans is encoded by the DPYS gene.
N6-adenosine-methyltransferase 70 kDa subunit (METTL3) is an enzyme that in humans is encoded by the METTL3 gene.
