Decarboxylase

UROD is the fifth enzyme in the human heme biosynthetic pathway and is in charge for the transfer of uroporphyrinogen to coproporphyrinogen through the deletion of four carboxymethyl side chains. UROD Mutations and deficiency result in 3 autosomal disorders in humans: familial porphyria cutanea tarda (f-PCT), sporadic porphyria cutanea tarda (s-PCT) and hepatoerythropoietic porphyria (HEP).

PPCDC is a member of the HFCD (homo oligomeric flavin containing Cys decarboxylase) superfamily which takes a part in the biosynthesis of coenzyme A (CoA) from pantothenate (Vitamin B). The biosynthesis of CoA from pantothenate needs several steps: the phosphorylation of pantothenate, the conversion of 4’-hosphopantothenate to 4''-phosphopantetheine, the adenylation by phosphopantetheine adenylyltransferase to form dephospho-CoA and the phosphorylation by dephospho-CoA kinase to form CoA. PPCDC is a key player in this pathway. PPCDC converts 4''-phosphopantothenate into 4''-phosphopantetheine.

Glutamate Decarboxylase 2 (GAD2) is one of several forms of glutamic acid decarboxylase, identified as a main autoantigen in type II diabetes. The GAD2 enzyme is responsible for catalyzing the production of gamma-aminobutyric acid from L-glutamic acid. A pathogenic role for the GAD2 enzyme has been characterized in the human pancreas since it has been identified as an autoantibody and an autoreactive T cell target in type II diabetes. GAD2 gene may also have a role in the stiff man syndrome. In addition, GAD2 catalyzes the production of GABA.

Glutamate Decarboxylase 1 Isoform-1, also known as GAD1 iso1 belongs to the group II decarboxylase family. GAD1 iso1 encodes one of several forms of glutamic acid decarboxylase, and is identified as a major autoantigen in insulin-dependent diabetes. GAD1 iso1 is in charge for catalyzing the production of gamma-aminobutyric acid from L-glutamic acid. In addition, a pathogenic function for GAD1 iso1 has been shown in the human pancreas while it has been identified as an autoantigen & an autoreactive T cell target in insulin-dependent diabetes. GAD1 iso1 play a role in the stiff man syndrome. It has been shown that deficiency in this enzyme has led to pyridoxine dependency with seizures.

Glutamate Decarboxylase 1 (GAD1) is one of several forms of glutamic acid decarboxylase. GAD1 is responsible for catalyzing the production of gamma-aminobutyric acid from L-glutamic acid. A pathogenic role for the GAD1 enzyme has been identified in the human pancreas since it has been detected as an autoantigen and an autoreactive T cell target type II diabetes. The GAD1 protein may also have a role in the stiff man syndrome. GAD1 enzyme deficiency leads to pyridoxine dependency with seizures. GAD1 also catalyzes the production of GABA.

Ornithine decarboxylase is the preliminary and rate-limiting enzyme in the biosynthetic pathway of polyamines and it takes part in the alteration of ornithine to putrescine. ODC1 is a key member of various biological processes, such as cell growth, transformation, differentiation and apoptosis. Overexpression of the ODC1 gene has a vital part in cell proliferation and the progress of cancer.

Dopa decarboxylase is a homodimeric, pyridoxal phosphate dependent enzyme.
Dopa decarboxylase is involved in 2 metabolic pathways, synthesizing 2 significant neurotransmitters the take part in numerous clinical disorders, including Parkinson’s disease. Dopa decarboxylase is located in different areas of the brain and is mostly found in basal ganglia. Dopa decarboxylase catalyzes the decarboxylation of L-3,4-dihydroxyphenylalanine (DOPA) to dopa, L-5-hydroxytryptophan to serotonin and L-tryptophan to tryptamine. Defects in Dopa decarboxylase leads to aromatic L-amino-acid decarboxylase deficiency (AADCD). AADCD deficiency is an inborn error in neurotransmitter metabolism that causes combined serotonin and catecholamine deficiency.

Adenosylmethionine decarboxylase proenzyme (AMD1) is synthesized originally as an inactive proenzyme. Putrescine stimulates both the proenzyme processing and the catalytic activity. The catalytic activity is inhibited by iodoacetic acid. The active enzyme formation entails a self-maturation process in which the active site pyruvoyl group is produced from an internal serine residue using an autocatalytic post-translational modification.

DDT is an enzyme that catayzes the tautomerization of D-dopachrome to give 5,6-dihydroxyindole (DHI). DDT is part of the family of lyases, specifically the carboxy-lyases, which cleave carbon-carbon bonds. DDT shares a homologous amino acid sequence (33% identical) with MIF and has similar tautomerase activity. DDT functions a proinflammatory cytokine.

DDT is an enzyme that catayzes the tautomerization of D-dopachrome to give 5,6-dihydroxyindole (DHI). DDT is part of the family of lyases, specifically the carboxy-lyases, which cleave carbon-carbon bonds. DDT shares a homologous amino acid sequence (33% identical) with MIF and has similar tautomerase activity. DDT functions a proinflammatory cytokine.

Diphosphomevalonate decarboxylase (MVD) catalyzes the conversion of mevalonate pyrophosphate into isopentenyl pyrophosphate in one of the early steps in cholesterol biosynthesis. MVD decarboxylates and dehydrates its substrate while hydrolyzing ATP. MVD is expressed in the heart, skeletal muscle, lung, liver, brain, pancreas, kidney and placenta.