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Ectonucleoside Triphosphate Diphosphohydrolase 3, also known as ENTPD3, which owns a threefold preference for the hydrolysis of ATP over ADP is similar to E-type nucleotidases (NTPases). ENTPD3 is a protein coding gene which contains four apyrase-conserved areas which is characteristic of NTPases.

X-Prolyl Aminopeptidase-1, also known as XPNPEP1 is a member of the peptidase M24B family. XPNPEP1 encodes the cytosolic form of a metalloaminopeptidase which catalyzes the cleavage of the N-terminal amino acid adjacent to a proline residue. Furthermore, XPNPEP1 plays a role in degradation as well as maturation of tachykinins, neuropeptides and peptide hormones.

Ectonucleoside Triphosphate Diphosphohydrolase 3, also known as ENTPD3, which owns a threefold preference for the hydrolysis of ATP over ADP is similar to E-type nucleotidases (NTPases). ENTPD3 is a protein coding gene which contains four apyrase-conserved areas which is characteristic of NTPases.

This gene is a member of the ADAR (adenosine deaminase acting on RNA) family. Using site-specific adenosine modification, proteins encoded by these genes participate in the pre-mRNA editing of nuclear transcripts. The protein encoded by this gene, tRNA-specific adenosine deaminase 1, is responsible for the deamination of adenosine 37 to inosine in eukaryotic tRNA.

Dopachrome Tautomerase also known as DCT, belongs to the tyrosinase family. DCT takes a significant part in the synthesis of the melanin pigment including tyrosinase (Tyr), tyrosinase-related protein 1 (Tyrp1). Which are highly involved in eumelanin synthesis. The change among the eumelanin and the pheomelanin pathways is assumed to depend on the presence of cysteine. Hence, in the lack of cysteine, dopaquinone, the product of tyrosinase action, is transformed to cyclodopa (leucodopachrome) and afterwards to dopachrome (and DOPA).

Membrane Metalloendopeptidase, also known as MME is a zinc metallopeptidase which is expressed at the cell surface of various cells. MME degrades the amyloid beta peptide whose abnormal misfolding as well as aggregation in neural tissue has been implicated as the cause for Alzheimer's disease. MME is expressed in an extended range of tissues and is especially plentiful in the kidney. MME is also a common acute lymphocytic leukemia antigen which is a significant cell surface marker in the diagnosis of human acute lymphocytic leukemia (ALL). MME is used in hematological diagnosis because it is expressed by early B, pro-B and pre-B lymphocytes, and also by lymph node germinal centers.

melA is a member of the glycosyl hydrolase 4 family. melA catalyze the hydrolysis of saccharides containing o-1,6,-galactoside bonds. melA catalyze the same reaction in E.coli, human and yeast but is found in different cellular sections: The E.coli melA is a cytoplasmic protein and the human and yeast melA are secretory proteins. Thus, even though the active enzyme from all three species has almost an equal molecular weight, structural resemblances, as well as dissimilarities, are probable.

GNMT is an enzyme that catalyzes the conversion of S-adenosyl-L-methionine with glycine to S-adenosyl-L-homocysteine and sarcosine. 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 (sarcosine) 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.

tRNA aspartic acid methyltransferase 1 (TRDMT1) is a member of the C5-methyltransferase family. TRDMT1 specifically methylates cytosine 38 in the anticodon loop of tRNA(Asp). TRDMT1 is a protein responsible for the methylation of aspartic acid transfer RNA, particularly at the cytosine-38 residue in the anticodon loop. In addition, the TRDMT1 enzyme has residual DNA-(cytosine-C5) methyltransferase activity. TRDMT1 is expressed ubiquitously; however it has a higher expression in the testis, ovary and thymus and at much lower levels in the spleen, prostate, colon, small intestine, and peripheral blood leukocytes. Though similar in sequence and structure to DNA cytosine methyltransferases, the TRDMT1 gene is distinctive and extremely conserved in its function between taxa.

Kell blood group glycoprotein homolog or KEL, is an enzyme, part of the zinc endopeptidase of the neprilysin (NEP) group of proteins. KEL has a crucial part in the production of the potent bioactive ET-3, which also includes enzymes that are endothelin convertingenzymes (PEX, XCE, DINE &various NEP-like proteins). KEL uses a single disulfide bond to XK, a gated membranal transporter. The Kell antigen system that includes two proteins, is very crucial among blood group systems.

Scavenger mRNA-decapping enzyme (DCPS) is a member of the HIT family. DCPS is required for the complete degradation of mRNAs, both in normal mRNA turnover and in nonsense-mediated mRNA decay. It was shown that DCPS hydrolyzes the residual m7GpppN cap structure after the complete 3'–5' degradation of the mRNA by the exosome. Furthermore, DCPS releases m7GMP and is incapable of cleaving cap structures attached to a long RNA chain.

Glycylpeptide N-tetradecan-oyltransferases 2 (NMT2) is a cytoplasmic protein which is a member of the NMT family of proteins. The proteins in the NMT family catalyze the addition of a myristoyl group to the N-terminal glycine residue of eukaryotic, fungal and viral proteins. These proteins are mostly detected in the heart, gut, kidney, liver and placenta. NMT catalyzes the reaction of N-terminal myristoylation of various signaling proteins. NMT transfers myristic acid from myristoyl coenzyme A to the amino group of a protein's N-terminal glycine residue. There are several distinct NMTs which vary in the molecular weight and /or subcellular distribution.

UPP1 catalyzes the reversible phosphorylytic cleavage of uridine and deoxyuridine to uracil and ribose- or deoxyribose-1-phosphate which are used as carbon and energy sources or in the release of pyrimidine bases for nucleotide synthesis. UPP1 is part of the family of glycosyltransferases, specifically the pentosyltransferases. Pyrimidine nucleoside phosphorylases add ribose or deoxyribose to pyrimidine bases to form nucleosides that can be incorporated into RNA or DNA.

Formylglutathione hydrolase (Esterase D) is a member of the esterase D family. Esterase D is a serine hydrolase involved in the detoxification of formaldehyde. Esterase D is active toward various substrates including O-acetylated sialic acids, and it may possibly be involved in the recycling of sialic acids. Esterase D is used as a genetic marker for retinoblastoma and Wilson's disease.

Isocitrate dehydrogenase [NAD] subunit gamma (IDH3G) mitochondrial is a member of the isocitrate and isopropylmalate dehydrogenases family. Isocitrate dehydrogenases catalyze the oxidative decarboxylation of isocitrate to 2-oxoglutarate. The IDH3G is a gamma subunit of one isozyme of isocitrate dehydrogenase which belongs to a distinct subclass, which utilizes NAD(+) as the electron acceptor, and is restricted to the mitochondrial matrix.

Epoxide Hydrolase 1 Microsomal (EPHX1) is a vital biotransformation enzyme which transfers epoxides from the degradation of aromatic compounds to trans-dihydrodiols that can be conjugated and excreted from the body. Epoxide hydrolase plays a role in both activation and detoxification of epoxides. Mutations in EPHX1 trigger preeclampsia, epoxide hydrolase deficiency or increased epoxide hydrolase activity.

Ectonucleotide Pyrophosphatase (ENPP1) belongs to the ecto-nucleotide pyrophosphatase/phosphodiesterase (ENPP) family. ENPP1 is a type II transmembrane glycoprotein comprised of 2 identical disulfide-bonded subunits. The ENPP1 protein has broad specificity and cleaves various substrates, including phosphodiester bonds of nucleotides and nucleotide sugars and pyrophosphate bonds of nucleotides and nucleotide sugars. The ENPP1 protein can hydrolyze nucleoside 5' triphosphates to their corresponding monophosphates and it may also hydrolyze diadenosine polyphosphates. ENPP1 gene mutations are linked with 'idiopathic' infantile arterial calcification and ossification of the posterior longitudinal ligament of the spine (OPLL).

Coproporphyrinogen Oxidase (CPOX) which is localized to the internal membrane space of erythrocytes takes part in the 6th phase of heme biosynthesis. CPOX catalyzes the oxidative decarboxylation of propionic acid side chains of rings A and B of coproporphyrinogen III. Mutations in human CPOX gene forecast the clinical result of the disease, with either hepatic hereditary coproporphyria or hematological manifestations of erythropoietic harderoporphyria.

Mercaptopyruvate Sulfurtransferase (MPST) catalyzes the transfer of a sulfur ion from 3-mercaptopyruvate to cyanide or other thiol compounds. MPST might be involved in cysteine degradation and cyanide detoxification. The MPST enzyme is regulated by oxidative stress and thioredoxin. In oxidative stress conditions, the catalytic cysteine site is transformed to a sulfenate which inhibits the MPST enzyme activity. The reduced thioredoxin cleaves an intersubunit disulfide bond to activate the redox switch and reactivate the enzyme. A deficiency in MPST activity is implicated in a rare inheritable condition known as MCDU (mercaptolactate-cysteine disulfiduria).

Aminomethyltransferase, mitochondrial isoform 1 (AMT) is a component of the glycine cleavage system termed T-protein. AMT reversibly catalyzes the degradation of the aminomethyl moiety of glycine attached to the lipoate cofactor of H-protein, leading to the production of ammonia, 5,10-methylenetetrahydrofolate, and dihydrolipoate-bearing H-protein in the presence of tetrahydrofolate.

Polyribonucleotide nucleotidyltransferase 1, also known as PNPT1 is predominantly localized in the mitochondrial intermembrane space and is implicated in the import of RNA to mitochondria. Mutations in PNPT1 have been connected with combined oxidative phosphorylation deficiency-13 as well as autosomal recessive nonsyndromic deafness-70. Related pseudogenes have been found on chromosomes 3 & 7.

Methionine aminopeptidase 1 (METAP1) is a member of the peptidase M24A family. METAP1 removes the amino-terminal methionine from nascent proteins. METAP1 releases N-terminal amino acids, preferentially methionine, from peptides and arylamides. METAP1 is essential for normal progression through the cell cycle. The active site of METAP1 contains 2 adjacent divalent metal ions linked by a water molecule or hydroxide ion.

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.

Betaine-homocysteine methyltransferase (BHMT) is a cytosolic enzyme that catalyzes the conversion of betaine and homocysteine to dimethylglycine and methionine, respectively. BHMT displays differential expression in a model of liver cirrhosis.