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Lipid hydroperoxide peroxidase (TPX) belongs to the peroxiredoxin family of antioxidant enzymes, which reduce hydrogen peroxide and alkyl hydroperoxides. TPX has an imperative role in thioredoxin peroxidase activity.

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.

Thiosulfate sulfurtransferase (glpE) is a mitochondrial matrix enzyme which is encoded by the nucleus. Escherichia coli glpE is a prototype for the single-domain rhodanese superfamily. glpE catalyzes the sulfur-transfer reaction in which a sulfur atom is transferred from thiosulfate to cyanide by a double-displacement mechanism.

Glutamate dehydrogenase 1, mitochondrial precursor (GLUD1) is a member of the Glu/Leu/Phe/Val dehydrogenases family. GLUD1 is a mitochondrial glutamate dehydrogenase, which converts L-glutamate into alpha-ketoglutarate. GLUD1 has a pivotal role in nitrogen metabolism in plants and animals. GLUD1 is observed in all organisms and catalyzes the oxidative deamination of 1-glutamate to 2-oxoglutarate. The GLUD1 enzyme has a vital role in regulating amino acid induced insulin secretion. GLUD1 gene mutations cause hyperinsulinism-hyperammonemia syndrome (HHS), which is an inherited condition characterized by high insulin and ammonia levels in the blood. GLUD1 enzyme is allosterically activated by ADP and inhibited by GTP and ATP.

Group IB secretory phospholipase A2 (sPLA2-IB) mediates cell proliferation, cell migration, hormone release and eicosanoid production via its receptor in peripheral tissues. In the CNS, high-affinity binding sites of sPLA2-IB have been documented. sPLA2-IB induced neuronal cell death in a concentrationdependent manner depending on PGD2 metabolites, especially Delta12-PGJ2 that might mediate sPLA2-IB-induced apoptosis. The secretory PLA2 (sPLA2) family, in which 10 isozymes have been identified, consists of lowmolecular weight, Ca2+-requiring secretory enzymes that have been implicated in a number of biological processes, such as modification of eicosanoid generation, inflammation, and host defense.

Chitinase is a digestive enzyme which breaks down glycosidic bonds in chitin. Due to chitin being a component of the cell walls of fungi and exoskeletal elements of some animals (including worms and arthropods), chitinases are usually found in organisms that either need to remake their own chitin or to dissolve and digest the chitin of fungi or animals. Chitinivorous organisms include many bacteria genuses such as Aeromonas, Bacillus, Vibrio, among others, which may be pathogenic or detritivorous. Chitinase expression is mediated by the NPR1 gene and the salicylic acid pathway, both of which are involved in resisting fungal and insect attack. Human chitinases appear in gastric juices. They are likely to be digestive chitinases, for catabolic activity. Chitinase activity is identified systemically in humans, in the blood, and possibly cartilage. Chitinase has been related to allergies, asthma in particular has been linked to enhanced chitinase expression levels, also dust mites and mold spores which are both chitin covered.

Luciferase is a general term for the class of oxidative enzymes used in bioluminescence and is distinct from a photoprotein. Luciferase catalyzes a bioluminescent reaction which involves the substrate luciferin as well as Mg2+ and ATP, produces green light with a wavelength of 562 nm. Luciferase from firefly is broadly used as a reporter for studying gene regulation and function, and for pharmaceutical screening.

Ectonucleoside Triphosphate Diphosphohydrolase 6 or ENTPD6 is an enzyme, akin to E-type nucleotidases. E-type nucleotidases, for instance CD39, are responsible for extracellular nucleotides catabolism. ENTPD6 has four apyrase-conserved areas like all to E-type nucleotidases. Rather spliced transcript agents that codes various isoforms were discovered for the DNA segment.

GMP synthase (GMPS) is involved in purine biosynthesis. GMPS, which is a homodimer, catalyzes the last step in the GMP synthesis pathway, specifically the ATP-dependent amination of XMP to GMP. GMPS is comprised of one GMP-binding domain and one glutamine amidotransferase type-1 domain through which it communicates its catalytic activity. GMPS is engaged in the de novo synthesis of nucleotides which are not only vital for DNA and RNA synthesis, but also supply GTP, which is involved in sevral cellular processes important for cell division. GMPS gene chromosomal translocations are linked with acute myeloid leukemias, suggesting a possible role for GMPS in carcinogenesis.

Phospholipase A2 (PLA2) catalyzes the hydrolysis of the sn-2 position of membrane glycerophospholipids to liberate arachidonic acid (AA), a precursor of eicosanoids including prostaglandins and leukotrienes. The same reaction also produces lysophosholipids, which represent another class of lipid mediators.
The secretory PLA2 (sPLA2) family, in which 10 isozymes have been identified, consists of lowmolecular weight, Ca2+-requiring secretory enzymes that have been implicated in a number of biological processes, such as modification of eicosanoid generation, inflammation, and host defense.
This enzyme has been proposed to hydrolyze phosphatidylcholine (PC) in lipoproteins to liberate lyso- PC and free fatty acids in the arterial wall, thereby facilitating the accumulation of bioactive lipids and modified lipoproteins in atherosclerotic foci.
In mice, sPLA2 expression significantly influences HDL particle size and composition and demonstrate that an induction of sPLA2 is required for the decrease in plasma HDL cholesterol in response to inflammatory stimuli. Instillation of bacteria into the bronchi was associated with surfactant degradation and a decrease in large:small ratio of surfactant aggregates in rats.
sPLA2-IIA can exert beneficial action in the context of infectious diseases since recent studies have shown that this enzyme exhibits potent bactericidal effects. Induction of the synthesis of sPLA2-IIA is generally initiated by endotoxin and a limited number of cytokines via paracrine and/or autocrine processes.

GNMT is an enzyme that catalyzes the conversion of S-adenosyl-L-methionine with glycine to S-adenosyl-L-homocysteine. GNMT is located in the cytoplasm and acts as a homotetramer. Defects in the GNMT gene causes of GNMT deficiency (hypermethioninemia). GNMT affects DNA methylation by regulating the ratio of S-adenosylmethionine to S-adenosylhomocystine and is involved in the detoxification pathway in liver cells. GNMT expression is diminished in human hepatocellular carcinoma (HCC). GNMT catalyzes the methylation of glycine by using s- adenosylmethionine (adomet) to form n-methylglycine with the concomitant production of s-adenosylhomocysteine (adohcy). GNMT plays an essential role in the regulation of tissue concentration of adomet and of metabolism of methionine.

Acetoacetyl-CoA thiolase (ACAT1) is an enzyme member of the membrane-bound acyltransferase family and Sterol o-acyltransferase subfamily. The ACAT1 enzyme catalyzes the reversible formation of acetoacetyl-CoA from 2 molecules of acetyl-CoA. ACAT1 plays a part in lipoprotein compilation and dietary cholesterol absorption. Added to its acyltransferase activity, ACAT1 acts as a ligase.

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.

ADP-ribosylhydrolase like 2 (ADPRHL2) belongs to the ADP-ribosylglycohydrolase family. ADPRHL2 catalyzes the removal of ADP-ribose from ADP-ribosylated proteins. ADPRHL2, which is ubiquitously expressed, uses magnesium as a cofactor to catalyze the hydrolysis of poly (ADP-ribose) that is synthesized after DNA damage. Furthermore, ADPRHL2 has an essential role in the maintenance of normal neuronal cell function. The ADPRHL2 enzyme localizes to the mitochondria, in addition to the nucleus and cytoplasm.

Dihydrofolate reductase (DHFR) is an enzyme that reduces dihydrofolic acid to tetrahydrofolic acid, with NADPH as electron donor that can be converted to the kinds of tetrahydrofolate cofactors applied in 1-carbon transfer chemistry. DHFR converts dihydrofolate into tetrahydrofolate, which is a methyl group shuttle required for the de novo synthesis of purines, thymidylic acid, and specific amino acids. Even though the functional DHFR gene is mapped to chromosome 5, numerous intronless processed pseudogenes or dihydrofolate reductase-like genes are identified on separate chromosomes.
DHFR deficiency is associated with megaloblastic anemia.
DHFR knockdown plays a role in the anticancer activity of 2-hydroxyoleic acid.
DHFR gene insertion/deletion polymorphism is linked to variation in serum and red blood cell folate concentrations in women.

Fatty Acid Amide Hydrolase 2 (FAAH2) shares a conserved protein motif with the amidase signature family of enzymes. FAAH2 catalyzes the hydrolysis of a broad range of bioactive lipids, including those from the 3 main classes of fatty acid amides; N-acylethanolamines, fatty acid primary amides and N-acyl amino acids. FAAH2 is also degrades bioactive fatty acid amides to their corresponding acids, thus helping to end the signaling functions of these molecules. FAAH2 prefers monounsaturated acyl chains as a substrate.

IVD is a mitochondrial matrix enzyme that is part of the cyl-CoA dehydrogenase family which catalyzes the third step in leucine catabolism. The genetic deficiency of IVD leads to a buildup of isovaleric acid, which is toxic to the central nervous system and results in isovaleric acidemia. IVD is a homotetrameric flavoenzyme which catalyzes the conversion of isovaleryl-CoA to 3-methylcrotonyl-CoA.

L-threonine to glycine degradation consists of a two-step biochemical pathway which involvs the enzymes L-threonine dehydrogenase and 2-amino-3-ketobutyrate coenzyme A ligase. L-Threonine is initially converted into 2-amino-3-ketobutyrate by L-threonine dehydrogenase. Glycine C-Acetyltransferase (GCAT) is the 2nd enzyme in this pathway, which subsequently catalyzes the reaction between 2-amino-3-ketobutyrate and coenzyme A to form glycine and acetyl-CoA. The GCAT enzyme is regard as a class II pyridoxal-phosphate-dependent aminotransferase. GCAT is strongly expressed in the heart, brain, liver and pancreas. GCAT is also found in lung.

MDH1 catalyzes the reversible oxidation of malate to oxaloacetate, using the NAD/NADH cofactor system in the citric acid cycle. MDH1 is abundantly found in the cytoplasm and is involved in the malate-aspartate shuttle that functions in the metabolic coordination between cytosol and mitochondria. MDH1 regulates p53-dependent cell-cycle arrest and apoptosis in response to glucose deprivation.

Heparanase is an endo β-D-glucuronidase, which degrades heparan sulfate side chains of heparan sulfate proteoglycans (HSPGs) in the extracellular matrix. Heparanase plays an important role in ECM degradation, facilitating the migration and extravasation of tumor cells and inflammatory leukocytes (1,2,3). Upon degradation, heparanase releases growth factors and cytokines that stimulate cell proliferation and chemotaxis (4,5). Heparanase is a heterodimer comprised of a 50 kDa subunit harboring the active site and a 8 kDa subunit. It is produced as a latent 65 kDa precursor and proteolytically processed to its active form (1,6). Heparanase is highly expressed in myeloid leukocytes (i.e. neutrophils) in platelets and in human placenta. Human heparanase was found to be upregulated in various types of primary tumors, correlating in some cases with increased tumor invasiveness and vascularity and with poor prospective survival (7,8).

Ornithine Aminotransferase is a mitochondrial enzyme which is an important factor that converts arginine and ornithine into the major excitatory and inhibitory neurotransmitters glutamate and GABA. Ornithine Aminotransferase mutations result in a deficiency that cause the autosomal recessive eye disease Gyrate Atrophy.

Acid phosphatase, prostate (ACPP) is a non-specific tyrosine phosphatase, which dephosphorylates a varied number of substrates under acidic conditions (pH 4-6) including alkyl, aryl, and acyl orthophosphate monoesters and phosphorylated proteins. ACPP has lipid phosphatase activity and inactivates lysophosphatidic acid in seminal plasma.

Cyclophilin-D is a member of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and speeds up the protein folding. Cyclophilin-D possess PPIase activity and binds to the immunosuppressant cyclosporin-A. Cyclophilin-D is very well known that its overexpression suppresses the apoptosis in cancer cell. Cyclophilin-D suppresses apoptotic cell death by the use of mitochondrial hexokinase-2 dependent mechanism in cancer cells.