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Glutathione peroxidase 3 (GPX3) is a member of the glutathione peroxidase family, which acts in the detoxification of hydrogen peroxide. GPX3 shields cells and enzymes from oxidative damage, by catalyzing the reduction of hydrogen peroxide, lipid peroxides and organic hydroperoxide, by glutathione. The GPX3 protein is one of only a few proteins known in higher vertebrates to contain selenocysteine, which occurs at the active site of glutathione peroxidase and is coded by the nonsense (stop) codon TGA.

SORD, also referred to as sorbitol dehydrogenase, belongs to the zinc-containing alcohol dehydrogenase family. It is widely produced. The lens of the eyeand the kidney are the protein highest production areas. Zinc-dependent interconversion of polyols, like sorbitol and xylitol, are enzymatically catalysed to their respective ketoses by SORD.

Glutathione peroxidase 2 (GPX2) is a member of the glutathione peroxidase family, consisting of 8 known glutathione peroxidases (Gpx1-8) in humans. Glutathione peroxidase functions in the detoxification of hydrogen peroxide, and is one of the most important antioxidant enzymes in humans. GPX2 may have a major role in protecting mammals from the toxicity of ingested organic hydroperoxides. GPX2 is one of only a few proteins known in higher vertebrates to contain selenocysteine, which appears at the active site of glutathione peroxidase and is coded by the nonsense (stop) codon TGA.

Glutathione peroxidase 1 (GPX1) is a member of the glutathione peroxidase family, consisting of 8 identified glutathione peroxidases (Gpx1-8) in humans. Glutathione peroxidase serves in the detoxification of hydrogen peroxide, and is one of the most vital antioxidant enzymes in humans. The GPX1 is a component of the enzymatic antioxidant defense, preventing oxidative damage to DNA, proteins and lipids by detoxifying hydrogen and lipid peroxides which may contribute to prostate cancer development. GPX1 is one of only a small number of proteins known in higher vertebrates to contain selenocysteine, which occurs at the active site of glutathione peroxidase and is coded by the nonsense (stop) codon TGA. Furthermore, the GPX1 protein is characterized in a polyalanine sequence polymorphism in the N-terminal region, which includes 3 alleles with 5, 6 or 7 alanine (ALA) repeats in this sequence. The allele with 5 ALA repeats is significantly linked to breast cancer risk.

DsbE is a reducing Dsb protein involved in electron transfer for cytochrome c maturation in the periplasm of Escherichia coli. DsbE is one of 12 proteins required for their assembly in the periplasm. DsbE functions is to decrease disulphide bonds formed among correctly paired cysteine residues in the cytochrome c apoproteins prior to haem attachment by CcmF and CcmH.

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.

PRDX2 is part of the peroxiredoxin family of antioxidant enzymes, which reduce hydrogen peroxide and alkyl hydroperoxides. PRDX2 takes part as an antioxidant protective role in cells, and contributes to the antiviral activity of CD8(+) T-cells. PRDX2 has proliferative effect in cancer development or progression.
If PRDX2 protection is insufficient against peroxidases, the DNA damage results in neurological disease such as Alzheimer's or DNA damage leading to cancer.

Lysyl Oxidase also known as LOX is an extracellular copper enzyme which initiates the crosslinking of collagens and elastin. LOX catalyzes oxidative deamination of the epsilon-amino group in certain lysine and hydroxylysine residues of collagens and lysine residues of elastin. Adding up to crosslinking extracellular matrix proteins, LOX plays a part in tumor suppression. Moreover, defects in LOX are the cause of autosomal recessive cutis laxa type I, CL type I. Two transcript variants encoding dissimilar isoforms have been found for LOX.

ALDH5A1 is a mitochondrial NAD(+)-dependent succinic semialdehyde dehydrogenase, which is a member of the aldehyde dehydrogenase family of proteins. The ALDH5A1 protein functions as a mediator to the NADP+-dependent oxidation of aldehydes into acids and has an imperative role in the detoxification of alcohol-derived acetaldehyde, as well as in lipid peroxidation and in the metabolism of corticosteroids, biogenic amines and neurotransmitters. ALDH5A1 is expressed in various tissues, including the liver, heart, lung, brain, kidney and placenta. Deficiency in the ALDH5A1 enzyme, known as 4-hydroxybutyricaciduria, is a rare inborn error in the metabolism of the neurotransmitter 4-aminobutyric acid (GABA). In response to this defect, physiologic fluids from patients accumulate GHB, which is a compound with numerous neuromodulatory properties.

Acireductone dioxygenase 1 (ADI1) is a part of the acireductone dioxygenase family of metal-binding enzymes, which are involved in methionine salvage. ADI1 regulates mRNA processing in the nucleus, and carries out different functions depending on its localization. Related pseudogenes have been defined on chromosomes 8 and 20. ADI1 down-regulates cell migration arbitrated by MMP14.

Peroxiredoxin 6 (PRDX6) belongs to the thiol-specific antioxidant protein family. PRDX6 is a bifunctional enzyme with 2 distinct active sites. PRDX6 is involved in redox regulation of the cell and can reduce Hydrogen peroxide and short chain organic, fatty acid, and phospholipid hydroperoxides. PRDX6 may have a role in the regulation of phospholipid turnover as well as in protection against oxidative injury. Furthermore, PRDX6 eases the oxidative stress and TGF-beta-induced abnormalities of human trabecular meshwork cells. In addition, PRDX6 is necessary for blood vessel integrity in injured skin.
At acidic pH, PRDX6 binds to reduced phospholipids, however at cytosolic pH PRDX6 binds only to phospholipids that are oxidized which is compatible with the role for PRDX6 in the repair of peroxidized cell membranes. Hydrogen peroxide-mediated hyperoxidation of PRDX6 induces cell cycle arrest at the G2/M transition via up-regulation of iPLA2 activity. Overexpression of PRDX6 is linked to oligodendroglioma.

Rab GDP dissociation inhibitor beta isoform 1 (GDI2) is a member of the GDP dissociation inhibitors (GDIs) family. GDI proteins can bind and release GDP-bound Rab proteins from membranes. GDI1 interacts with virtually all of the Rab proteins, whereas GDI2 interacts with Rabll but not Rab3A. GDI2 distributes ubiquitously, presenting a membrane bound location in perinuclear regions of cells.

Dsb proteins are in charge for the formation and rearrangement of disulfide bonds during the folding of secreted and membrane proteins in bacteria. DsbG has disulfide bond isomerase and chaperone activity. DsbG interacts with refolding intermediates of chemically denatured citrate synthase and prevents their aggregation in vitro. DsbG shares sequnce homology with DsbC. DsbG forms a stable periplasmic dimer and displays an equilibrium constant with glutathione comparable with DsbA and DsbC. DsbG is expressed at roughly 25% level of DsbC.

Protein disulfide isomerases (PDIs) constitute a family of structurally related enzymes which catalyze disulfide bonds formation, reduction, or isomerization of newly synthesized proteins in the lumen of the endoplasmic reticulum (ER). They act also as chaperones, and are, therefore, part of a quality-control system for the correct folding of the proteins in the same subcellular compartment. PDI has been found to have moderate effects (25-fold) on the rate of oxidative folding of proteins in vitro.
Recombinant Human Protein Disulfide Isomerase is involved in disulphide-bond formation and isomerization, as well as the reduction of disulphide bonds in proteins. Recombinant PDI has been found to have moderate effects (25-fold) on the rate of oxidative folding of proteins in vitro.

SAE1 is part of the ubiquitin-activating E1 family of proteins and participates in the significant first step of the UBL1 conjugation pathway. Proteins conjugated to Ub are marked for progressive degradation by the 26S Proteasome. SAE1 acts as a UBLI E1 ligase mediating the ATP-dependent activation of UBL1. SAE1 binds with UBLE1A and UBLE1B to form a heterodimer which can bind UBL1. SAE1 is a dimeric enzyme that takes part as a E1 ligase for SUMO1, SUMO2, SUMO3, and probably SUMO4. SAE1 regulates ATP-dependent activation of SUMO proteins and formation of a thioester with a conserved cysteine residue on SAE2.

Thioredoxin reductase (TrxR/NTR), an enzyme belonging to the flavoprotein family of pyridine nucleotide-disulfide oxidoreductases. Thioredoxin reductase (TrxR), a component of the thioredoxin system, including thioredoxin (Trx) and NADPH, catalyzes the transfer of electrons from NADPH to Trx, acts as a reductant of disulfide-containing proteins and participates in the defense system against oxidative stresses.

Malate dehydrogenase (EC1.1.1.37) is an enzyme in the citric acid cycle that catalyzes the conversion of malate into oxaloacetate (using NAD+) and vice versa (this is a reversible reaction). Malate dehydrogenase is not to be confused with malic enzyme, which catalyzes the conversion of pyruvate using NADPH.
Malate dehydrogenase is also involved in gluconeogenesis, the synthesis of glucose from smaller molecules. Pyruvate in the mitochondria is acted upon by pyruvate carboxylase to form oxaloacetate, a citric acid cycle intermediate. In order to get the oxaloacetate out of the mitochondria, malate dehydrogenase reduces it to malate, and it then traverses the inner mitochondrial membrane. Once in the cytosol, the malate is oxidized back to oxaloacetate by cytosolic malate dehydrogenase. Finally, phosphoenol-pyruvate carboxy kinase (PEPCK) converts oxaloacetate to phosphoenol pyruvate.

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.

Methionine sulfoxide reductase B3 (MSRB3) is a member of the methionine sulfoxide reductases (MSR) family proteins. MSRB3 catalyzes the reduction of methionine sulfoxide to methionine. The MSRB3 enzyme acts as a monomer and requires zinc as a cofactor. MSRs are thought to defend against reactive oxygen species-induced oxidative damage in various organs, including the most environmentally exposed organ, the human skin. MSRB3 has a vital role in cold tolerance by eliminating MetO and ROS which accumulate at the ER during cold acclimation.

Sepiapterin Reductase is an aldo-keto reductase that catalyzes the NADPH-dependent reduction of pteridine derivatives and is essential in the biosynthesis of BH4. Mutations in Sepiapterin Reductase gene result in DOPA-responsive dystonia due to sepiaterin reductase deficiency defined by the presence of sustained involuntary muscle contractions, often leading to abnormal postures. Sepiapterin reductase is part of the short-chain dehydrogenase/reductase family which reduces exogenous carbonyl compounds as well as phenylpropanedione. Sepiapterin reductase is an important enzyme for the biosynthesis of tetrahydrobiopterin, an necessary cofactor for aromatic amino acid hydrolases together with tyrosine hydroxylase, the rate-limiting enzyme in DOPA synthesis.

DCTD is an allosteric enzyme that exists as a homohexamer and is part of the cytidine and deoxycytidylate deaminase protein family. DTCD uses zinc as a cofactor to catalyze the deamination of dCMP to dUMP, thus making the nucleotide substrate (dUMP) that is used by thymidylate synthase.

Inositol oxygenase is a non-heme di-iron enzyme which oxidizes myo-inositol to glucuronic acid. In addition, inositol oxygenase oxidizes the less abundant chiro isomer of inositol. MIOX enzyme is a component of the only known pathway for the catabolism of inositol in humans. MIOX is expressed mostly in the kidneys. Reduction of Inositol Oxygenase and accumulation of polyols, such as inositol and xylitol, have been implicated as contributing factors in complications linked with diabetes.

DLAT gene encodes component E2 of the multi-enzyme pyruvate dehydrogenase complex (PDC). PDC is located in the inner mitochondrial membrane and catalyzes the conversion of pyruvate to acetyl coenzyme A. The protein product of this gene, dihydrolipoamide acetyltransferase, takes acetyl groups created by the oxidative decarboxylation of pyruvate and transfers them to coenzyme A. Dihydrolipoamide acetyltransferase is the antigen for antimitochondrial antibodies which are found in about 95% of patients with the autoimmune liver disease primary biliary cirrhosis (PBC). In patients who suffer from this illness, activated T lymphocytes attack and destroy epithelial cells in the bile duct where this protein is abnormally distributed and overexpressed. PBC ultimately leads to cirrhosis and liver failure. Mutations in DLAT are also a cause of pyruvate dehydrogenase E2 deficiency which causes primary lactic acidosis in infancy and early childhood.

Cathepsin D is synthesized as a 54kDa precursor, which is proteolytically processed to an intermediate 48kDa single chain, which matures into more stable 34kDa and 14kDa two chain form. It is an estrogen-regulated lysosomal protease that has been suggested to facilitate cancer cell migration and invasion by digesting the basement membrane, extracellular matrix, and xonnective tissue. Because of its mitogenic and proteolytic activities, it has been implicated as a prognostic marker in many tumor types. Cathepsin D is expressed in epithelial cells as well as in macrophages.