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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.

Thrombin enzyme (Activated Factor IIa) is an important clotting promoter that controls the transformation of soluble fibrinogen to insoluble active fibrin strands. Thrombin is a coagulation protein and a serine protease (EC 3.4.21.5) that catalyzes many coagulation-related reactions. Thrombin triggers factor-XI, factor-V, Factor-XIII and factor-VIII. Thrombin endorses platelet activation, using activation of protease-activated receptors on the platelet. As a result of its high proteolytic specificity, thrombin has become an important biochemical protein. The thrombin cleavage site (Leu-Val-Pro-Arg-Gly-Ser) is widely used in linker regions of recombinant fusion protein constructs. After the purification of the fusion protein, thrombin is used to cleave between the Arginine and Glycine residues of the cleavage site, efficiently removing the purification tag from the protein of interest with a high degree of specificity.

Shiga-like toxin (verotoxin) is a toxin produced by some strains of Escherichia coli. Shiga-like toxin is named for its similarity to the AB5-type Shiga toxin produced by the bacteria Shigella dysenteriae. There are two known types-SLT1 and SLT2. The Shiga-like toxin is linked with hemolytic-uremic syndrome. Shiga-like toxin requires highly specific receptors on the cells' surface in order to attach and enter the cell. Species such as cattle, swine, and deer which do not carry these receptors may harbor toxigenic bacteria without any ill effect, dropping them in their feces, from where they may be distributed to humans. Shiga Like Toxin-1 Subunit B has nontoxic action, it is the functional region which binds to the receptor. The Shiga Like Toxin-1 Subunit B can be useful in vaccine study, antibody test and other functional research.

Cytosolic and membrane-bound types of GST are encoded by 2 different supergene families. There are 8 classes of the soluble cytoplasmic mammalian GST: alpha, kappa, mu, omega, pi, sigma, theta and zeta. The mu class of enzymes functions in the detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress, by conjugation with glutathione. The genes encoding the mu class of enzymes are arranged in a gene cluster on chromosome 1p13.3 and aare highly polymorphic. These genetic differences can change an individual's resistance to carcinogens and toxins as well as affect the toxicity and efficacy of certain drugs. Null mutations of this class mu gene have been linked with the rise in a number of cancers.

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.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

GSTM3 belongs to the glutathione s-transferase (GST) family of proteins. There are eight GST proteins families, named alpha, kappa, mu, omega, pi, sigma, theta and zeta. Each one of the GST families has several proteins with different functions throughout the cell. The mu type of enzymes takes part in the detoxification of electrophilic compounds, including therapeutic drugs, carcinogens, environmental toxins and products of oxidative stress, by conjugation with glutathione.

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).

Paraoxonase 2 (PON2) is a member of a multigene family whose genes share 65% identity at the amino acid level, and is expressed in a variety of tissues, including the pancreas. PON2 overexpression has been shown to lower the intracellular oxidative state and reduce the cells ability to oxidize LDL. PON2 is therefore implicated in the modulation of oxidative stress.

ENO1 is a homodimeric soluble protein that encodes a smaller monomeric structural lens protein, tau-crystallin. ENO1 is a glycolytic enzyme expressed in mainly all tissues. ENO1 isoenzyme full length protein is found in the cytoplasm. The shorter protein is formed from another translation start that is restricted to the nucleus, and binds to a component in the c-myc promoter. ENO1 is involved in anaerobic metabolism under hypoxic conditions and plays a role as a cell surface plasminogen receptor during tissue invasion. Irregular expression of Enolase-1 is linked with tumor progression in several cases of breast and lung cancer. Enolase-1 is as an auto antigen associated with Hashimoto's encephalopathy and severe asthma. ENO1 is the target protein of serum anti-endothelial antibody in Behcet's disease.

Janus Kinase 2 (JAK2) is a protein tyrosine kinase which takes part in a specific subset of cytokine receptor signaling pathways such as cell growth, development, differentiation or histone modifications. JAK2 is linked with the prolactin receptor and is necessary for responses to gamma IFN. Mice which do not express an active protein for JAK2 show embryonic lethality associated with the absence of definitive erythropoiesis.

Caspase 3 Apoptosis-Related Cysteine Peptidase (CASP3) belongs to the cysteine-aspartic acid protease (caspase) family. Sequential activation of caspases plays a key role in the execution-phase of cell apoptosis. Caspases exist as inactive proenzymes which undergo proteolytic processing at conserved aspartic residues to generate 2 subunits, large and small, that dimerize to create the active enzyme. CASP3 protein cleaves and activates caspases 6, 7 and 9, and the protein itself is processed by caspases 8, 9 and 10. CASP3 is the leading caspase involved in the cleavage of amyloid-beta 4A precursor protein, which is linked with neuronal death in Alzheimer's disease. In addition, CASP3 is involved in the cleavage of huntingtin. CASP3 also cleaves and activates sterol regulatory element binding proteins (SREBPs) between the basic helix-loop-helix leucine zipper domain and the membrane attachment domain. CASP3 initiates cell adhesion in sympathetic neurons through RET cleavage.

UDP Glucuronosyltransferase 1 Family Polypeptide A1, also known as UGT1A1 has a main importance in the conjugation as well as subsequent elimination of potentially toxic xenobiotics and endogenous compounds. UGT1A1 is also capable of catalyzing glucuronidation of 17beta, 17alpha, 1-hydroxypyrene, 4-methylumbelliferone, 1-naphthol, paranitrophenol, scopoletin, and umbelliferone.

Tissue plasminogen activator (abbreviated PLAT or tPA) is a secreted serine proteasewhich converts the proenzymeplasminogento plasmin, a fibrinolyticenzyme. Plasminogen is synthesized as a single chain which is cleaved by PLAT into the two chain disulfide linked plasmin.
This enzyme plays a role in cell migrationand tissue remodeling. Increased enzymatic activity causes hyperfibrinolysis, which manifests as excessive bleeding; decreased activity leads to hypofibrinolysiswhich can result in thrombosisor embolism.

MAPK3 is a part of the MAP kinase family which is recognized as extracellular signal-regulated kinases (ERKs), that function in a signaling cascade that controls various cellular procedures such as proliferation, differentiation, and cell cycle progression in reaction to a variety of extracellular signals. MAPK3 is activated by upstream kinases, resulting in its translocation to the nucleus where it phosphorylates nuclear targets.

Peptidase Inhibitor 16 (PI16) which a member of the CRISP family, is a putative serine protease inhibitor. PI16 interacts with PSP94/MSMB. PI16 is expressed in the prostate, testis, ovary and intestine. It also concentrates in prostate cancer patient's sera. PI16 may serve as a marker following prostatectomy for prostate cancer.

The protein kinase A holoenzyme is a heterotetramer composed of two types of subunits: Catalytic and Regulatory. The Catalyticsubunit contains the enzyme's active site. It also contains a domain that binds ATP and a domain that binds the regulatory subunit. The Regulatory subunit consists oftwo molecules which bind one another in an anti-parallel orientation to form a homodimer; for type I subunits- this binding is covalent via disulfide bonds. This subunit also has has two domains that bind cyclic AMP, a domain that interacts with a catalytic subunit, and an "auto-inhibitory" domain that serves as a substrate or pseudosubstrate for the catalytic subunit. Regulatory subunits may also have biologic activity distinct from their role in modulating catalytic subunit activity. Regulatory subunits exist in two major forms, RI and RII, with each form having two subtypes designated alpha and beta. Each of the four isotypes of the regulatory subunit is encoded by a different gene. In addition, three isotypes of the catalytic subunit have been identified (alpha, beta and gamma). The different isotypes tend to have different distributions within cells and among tissues. Type I enzymes inhabit cytoplasmic, soluble fractions of the cell, whereas type II enzymes tend to associate with cellular membranes.

Prostaglandin Reductase 2 (PTGR2) is a member of the medium-chain dehydrogenase/reductase superfamily. PTGR2 is an enzyme involved in the metabolism of prostaglandins. PTGR2 catalyzes an NADPH-dependent reduction of the conjugated alpha, beta-unsaturated double bond of 15-keto-PGE(2), which is a fundamental step in terminal inactivation of prostaglandins and suppression of PPARgamma-mediated adipocyte differentiation. PTGR2 may also be involved in controlling activation of the peroxisome proliferator-activated receptor.

GSTO1 belongs to the theta class glutathione S-transferase-like (GSTTL) protein family. GSTO1 is expressed in a broad array of human tissues and exhibits glutathione-dependent thiol transferase and dehydroascorbate reductase activities as well as catalyzing the reduction of monomethylarsonate which is an intermediate in the pathway of arsenic biotransformation. Furthermore, GSTO1 shields from oxidative stress which is a risk factor for Alzheimer disease, vascular dementia and stroke. GSTO1 is abundant in alveolar macrophages and airway secretions, with the levels reduced in chronic obstructive pulmonary disease patients. In mouse, the GSTO1 protein acts as a small stress response protein, probably involved in cellular redox homeostasis.

BLMH is affiliate to the papain superfamily of the cysteine protease and the peptidase C1 family. BLMH is a cytoplasmic cysteinepeptidase usually found as a homohexamer. The standard physiological role of BLMH has not been determined, but it shields normal and malignant cells from the glycopeptide antitumor drug BLM. BLMH catalyzes the inactivation of the antitumor drug BLM (a glycopeptide) by hydrolyzing the carboxyamide bond of its B-aminoalaninamide moiety and in addition demonstrates general aminopeptidase activity.

DHPS is vital for the first step of hypusine biosynthesis. DHPS catalyzes the NAD-dependent transfer of the butylamine moiety of spermidine to the epsilon-amino group of a specific lysine residue of the EIF5A precursor protein to form the intermediate deoxyhypusine residue.

SERPINA1 is secreted and is a serine protease inhibitor which its targets include elastase, plasmin, collagenase, leucocytic proteases, trypsin, chymotrypsin, and plasminogen activator. Defects in SERPINA1 gene can cause emphysema or liver disease. SERPINA1 is an endogenous inhibitor of serine proteases and inhibits the catalytic domain of human recombinant matriptase in vitro. Rise in SERPINA1 occurs as an acute phase response to tissue necrosis and inflammation. mutations in SERPINA1 and SLC11A1 genes change the balance between elastase produced by leukocytes during phagocytosis.

NANS is a 359 amino acid protein that contains one AFP (antifreeze proteins)-like domain and functions in the biosynthesis of sialic acids. The ubiquitously expressed NANS enzymatically catalyzes the H2O-dependent formation of N-acetylneuraminic acid (Neu5Ac) and 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN), both of which are sialic acids. NANS uses N-acetylmannosamine 6-phosphate as a substrate for Neu5Ac synthesis and mannose 6-phosphate as a substrate for KDN synthesis.

PRSS3 is a trypsinogen, and a member of the trypsin family of serine proteases. PRSS3 is expressed in the pancreas and brain and is unaffected by common trypsin inhibitors. It is active on peptide linkages involving the carboxyl group of lysine or arginine. PRSS3 is restricted to the locus of T cell receptor beta variable orphans on chromosome 9. 4 different isoforms encoded by 4 transcript variants were identified for this gene.