Phenylalanine hydroxylase (PAH) (EC 1.14.16.1) is an enzyme that catalyzes the hydroxylation of the aromatic side-chain of phenylalanine to generate tyrosine. PAH is one of three members of the biopterin-dependent aromatic amino acid hydroxylases, a class of monooxygenase that uses tetrahydrobiopterin (BH4, a pteridine cofactor) and a non-heme iron for catalysis. During the reaction, molecular oxygen is heterolytically cleaved with sequential incorporation of one oxygen atom into BH4 and phenylalanine substrate. In humans, mutations in its encoding gene, PAH, can lead to the metabolic disorder phenylketonuria.
Aldolase A, also known as fructose-bisphosphate aldolase, is an enzyme that in humans is encoded by the ALDOA gene on chromosome 16.
Citrate synthase is an enzyme that exists in nearly all living cells. It functions as a pace-making enzyme in the first step of the citric acid cycle. Citrate synthase is located within eukaryotic cells in the mitochondrial matrix, but is encoded by nuclear DNA rather than mitochondrial. It is synthesized using cytoplasmic ribosomes, then transported into the mitochondrial matrix.
Glutaryl-CoA dehydrogenase (GCDH) is an enzyme encoded by the GCDH gene on chromosome 19. The protein belongs to the acyl-CoA dehydrogenase family (ACD). It catalyzes the oxidative decarboxylation of glutaryl-CoA to crotonyl-CoA and carbon dioxide in the degradative pathway of L-lysine, L-hydroxylysine, and L-tryptophan metabolism. It uses electron transfer flavoprotein as its electron acceptor. The enzyme exists in the mitochondrial matrix as a homotetramer of 45-kD subunits. Mutations in this gene result in the metabolic disorder glutaric aciduria type 1, which is also known as glutaric acidemia type I. Alternative splicing of this gene results in multiple transcript variants.
Serine hydroxymethyltransferase (SHMT) is a pyridoxal phosphate (PLP) (Vitamin B6) dependent enzyme (EC 2.1.2.1) which plays an important role in cellular one-carbon pathways by catalyzing the reversible, simultaneous conversions of L-serine to glycine and tetrahydrofolate (THF) to 5,10-methylenetetrahydrofolate (5,10-CH2-THF). This reaction provides the largest part of the one-carbon units available to the cell.
2,4 Dienoyl-CoA reductase also known as DECR1 is an enzyme which in humans is encoded by the DECR1 gene which resides on chromosome 8. This enzyme catalyzes the following reactions
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:
Guanosine monophosphate synthetase, also known as GMPS is an enzyme that converts xanthosine monophosphate to guanosine monophosphate.
Tyrosine aminotransferase is an enzyme present in the liver and catalyzes the conversion of tyrosine to 4-hydroxyphenylpyruvate.
Prosaposin, also known as PSAP, is a protein which in humans is encoded by the PSAP gene.
Aminomethyltransferase is an enzyme that catabolizes the creation of methylenetetrahydrofolate. It is part of the glycine decarboxylase complex.
The catalytic subunit α of protein kinase A is a key regulatory enzyme that in humans is encoded by the PRKACA gene. This enzyme is responsible for phosphorylating other proteins and substrates, changing their activity. Protein kinase A catalytic subunit is a member of the AGC kinase family, and contributes to the control of cellular processes that include glucose metabolism, cell division, and contextual memory. PKA Cα is part of a larger protein complex that is responsible for controlling when and where proteins are phosphorylated. Defective regulation of PKA holoenzyme activity has been linked to the progression of cardiovascular disease, certain endocrine disorders and cancers.
Sepiapterin reductase is an enzyme that in humans is encoded by the SPR gene.
Guanidinoacetate N-methyltransferase is an enzyme that catalyzes the chemical reaction and is encoded by gene GAMT located on chromosome 19p13.3.
In enzymology, a kynurenine 3-monooxygenase (EC 1.14.13.9) is an enzyme that catalyzes the chemical reaction
Glycine decarboxylase also known as glycine cleavage system P protein or glycine dehydrogenase is an enzyme that in humans is encoded by the GLDC gene.
Cystathionine beta-lyase, also commonly referred to as CBL or β-cystathionase, is an enzyme that primarily catalyzes the following α,β-elimination reaction
The enzyme Acid-Induced Arginine Decarboxylase (AdiA), also commonly referred to as arginine decarboxylase, catalyzes the conversion of L-arginine into agmatine and carbon dioxide. The process consumes a proton in the decarboxylation and employs a pyridoxal-5'-phosphate (PLP) cofactor, similar to other enzymes involved in amino acid metabolism, such as ornithine decarboxylase and glutamine decarboxylase. It is found in bacteria and virus, though most research has so far focused on forms of the enzyme in bacteria. During the AdiA catalyzed decarboxylation of arginine, the necessary proton is consumed from the cell cytoplasm which helps to prevent the over-accumulation of protons inside the cell and serves to increase the intracellular pH. Arginine decarboxylase is part of an enzymatic system in Escherichia coli, Salmonella Typhimurium, and methane-producing bacteria Methanococcus jannaschii that makes these organisms acid resistant and allows them to survive under highly acidic medium.
Galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase 3 is an enzyme that in humans is encoded by the B3GAT3 gene.
Kynurenine 3-monooxygenase is an enzyme that in humans is encoded by the KMO gene.
