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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.

E.Coli Acetate Kinase, also knowns as ACKA, catalyzes the formation of acetyl phosphate from acetate and ATP and also catalyzes the reverse reaction. ACKA takes part in synthesis of various ATP formed catabolically during anaerobic growth of the organism.

Matrix Metallopeptidase 23B (MMP23B) belongs to the matrix metalloproteinase (MMP) family, and it is section of a duplicated region of chromosome 1p36.3. MMP23B is a protease. MMP23B regulates the surface expression of some potassium channels by holding them in the endoplasmic reticulum. Members of the matrix metalloproteinase (MMP) family are involved in the breakdown of extracellular matrix in normal physiological processes, such as embryonic development, reproduction, and tissue remodeling, as well as in disease processes, such as arthritis and metastasis.

Cytochrome b5 reductase 2 (CYB5R2) is involved in desaturation and elongation of fatty acids, cholesterol biosynthesis, drug metabolism, and, in erythrocyte, methemoglobin reduction. CYB5R2 is responsible for NADH-dependent lucigenin chemiluminescence in spermatozoa by reducing both lucigenin and 2-[4-iodophenyl]-3-[4-nitrophenyl]-5-[2,4-disulfophenyl]-2H tetrazolium monosodium salt (WST-1).

NUDT16 is nuclear nucleoside diphosphatase proteins restricted in foci in the nucleolus and nucleoplasm. NUDT16 is a RNA-decapping enzyme. It binds specifically to U8 snoRNA and can remove m7G and m227G caps from RNAs, rendering them substrates for 5’-3’ exonucleases for degradation in vivo.

O-Sialoglycoprotein Endopeptidase, also known as OSGEP is a member of the KAE1 / TsaD family. OSGEP is essential for the formation of threonylcarbamoyl group on adenosine at position 37 (t6A37) in tRNAs which read codons beginning with adenine. OSGEP take a direct catalytic part in the above reaction, however other proteins of the complex are required to fulfill this activity.

Carbonic anhydrase 1 is a zinc metalloenzyme that catalyses reversible hydration of CO2 (CO2 + H2O ? HCO3- + H+). Carbonic anhydrase 1 is essential to many biological processes such as cellular respiration, calcification, acid-base balance, bone resorption, and the formation of aqueous humor, cerebrospinal fluid, salvia, and gastric acid. Carbonic anhydrase 1 is abundant in erythrocytes and an early marker for erythroid differentiation.

CAPSL is a calcium-binding protein holding two conserved calcium-binding motifs (EF-hands) which are found in a superfamily of calcium sensors and calcium signal modulators. In addition, the CAPSL gene is in the same linkage disequilibrium (LD) block as the IL7R gene and there is well known association between the CAPSL-IL7R locus and type 1 diabetes.

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.

Human Ubquitin Conjugating Enzyme 9 (Ubc9) is a member of the E2 family and is specific for the conjugation of SUMO to a variety of target proteins. SUMO conjugation to target proteins is mediated by a different, but analogous, pathway to ubiquitinylation. This E2 is unusual in that it interacts directly with protein substrates that are modified by sumolyation, and may play a role in substrate recognition. Ubc9 can mediate the conjugation of SUMO-1 to a variety of proteins including RanGAP1, I?B?, and PML without the requirement of an E3 ligase.

UCHL5 is a member of the peptidase C12 family. UCHL5 protein is a protease that specifically cleaves 'Lys-48'-linked polyubiquitin chains, and deubiquitinating enzyme related to the 19S regulatory subunit of the 26S proteasome.

Antioxidant enzyme Glutathione S- Transferase (GST) is thought to do the primary cellular defense mechanism against reactive oxygen species. GST reduces lipid hydroperoxides through its Se-independent glutathione peroxidase activity. The enzyme also detoxifies lipid peroxidation end products such as 4-hydroxynonenal (4-HNE).
The soluble GST is a 26 kDa protein which occurs as a dimer in all aerobic organisms. Each monomer has two domains, one that binds GSH and is an /-structure similar to thioredoxin and the other, all helical, that binds the hydrophobic substrate. The GST -fusion protein expression system is a widely used recombinant protein expression system that allows a peptide or a regulatory protein domain to be expressed as a fusion to the C-terminus of Schistosoma japonicum GST. Fusion proteins also possess GST -enzymatic activity and can undergo dimerization similar to in vivo. The fusion protein can be purified via GST -affinity column chromatography. In most cases, the desired peptides or domains are removed from GST by applying a specific protease that recognizes and cleaves the linker between the protein domain and GST. The technique has been widely used to generate different kinds of proteins for crystallization, molecular immunology studies, the production of vaccines and studies involving protein-protein and protein-DNA interactions.

Membrane-bound & Cytosolic forms of GST are encoded by 2 separate supergene families. These enzymes function in the detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress, by conjugation with glutathione. There are 8 different classes of soluble cytoplasmic mammalian GST: alpha, kappa, mu, omega, pi, sigma, theta and zeta. The GSTA1 is found in a cluster mapped to chromosome 6, and is highly expressed in the liver. GSTA1 protects the cells from reactive oxygen species.

MAT2B is part of the methionine adenosyltransferase family. MAT2B catalyzes the biosynthesis of S-adenosylmethionine from methionine and ATP. MAT2B is the regulatory beta subunit of MAT. MAT2B expression in hepatoma cell lines increases DNA synthesis and thus take part in cell proliferation.

Carbohydrate Sulfotransferase 5 (CHST5) is a Golgi-embedded enzyme that is found in B cells, T cells and intestinal epithelium and is also mediates sulfation of keratan in cornea. CHST5 is a sulfotransferase that utilizes 3'-phospho-5'-adenylyl sulfate (PAPS) as sulfonate donor to catalyze the transfer of sulfate to position 6 of non-reducing N-acetylglucosamine residues of keratan. CHST5 works on the non-reducing terminal GlcNAc of short andlong carbohydrate substrates that have poly-N-acetyllactosamine structures.

AK3L1 is an affiliate of the adenylate kinase family of enzymes. AK3L1 enzyme is restricted to the mitochondrial matrix. Adenylate kinases-3 regulates the adenine and guanine nucleotide compositions within a cell by means of catalyzing the reversible transfer of phosphate group among these nucleotides. 5 different isozymes of adenylate kinase have been identified in vertebrates. The enzyme expression of various adenylate kinase isozymes is growth regulated and tissue-specific.

Amelogenin, X-Linked (AMELX) belongs to the amelogenin family of extracellular matrix proteins. Amelogenins have a role biomineralization during tooth enamel development. AMELX gene mutations cause X-linked amelogenesis imperfecta. AMELX regulates the formation of crystallites during the secretory stage of tooth enamel development. AMELX is transiently but amply expressed by ameloblasts during tooth development. Amelogenin is the principal protein in developing dental enamel.

GZMB or Granzyme-B is a protein that mainly exist in granules of NK cells and T cells (cytotoxic), it is a serine protease. The protein is secreted by of NK cells and T cells together with the protein that creates pores (perforin) in order to lead to apoptosis in the target cell.

Alpha-2 Macroglobulin is a serine proteases inhibitor, which inhibits coagulation by inactivating thrombin and Kallikrein, it inhibits fibrinolysis by inactivating plasmin and involved in transport. Alpha-2-Macroglobulin is a large plasma protein, which is produced by the liver, it’s composed of 4 identical subunits bound together by -S-S- bonds. A2M is able to inactivate many kinds of proteinases (including serine-, cysteine-, aspartic- and metalloproteinases). A2M has a 35 amino acid "bait" region in its structure. Proteinases bind and cleave the “bait” region become bound to A2M. Macrophage receptors recognize the proteinase-A2M complex and clear it from the system. A2M binds to and removes MMP-2 and MMP-9 (active forms of the gelatinase) from the circulation using scavenger receptors on the phagocytes. The levels of Alpha-2-macroglobulin are increased in nephrotic syndrome which is a condition where the kidneys start to leak out some of the smaller blood proteins. Due to its large size, A2-macroglobulin is retained in the bloodstream. Increased production of all proteins causes A2-macroglobulin concentration to increase. Chronic renal failure might lead to amyloid by alpha-2-macroglobulin. A2M is raised in cirrhosis, pregnancy and diabetes.

Listeriolysin O (aka LLO) is a hemolysin produced by Listeria monocytogenes bacteria, the pathogen responsible for causing listeriosis. The toxin may be regarded as a virulence factor, since it is crucial for the virulence of L. monocytogenes. LLO is a single polypeptide protein encoded by the hlyA gene and composed of 529 residues. LLO is a thiol-activated cholesterol-dependent pore forming toxin protein; therefore, it is activated by reducing agents and inhibited by oxidizing agents. Still, LLO differs from other thiol-activated toxins, as its cytolytic activity is maximized at a pH of 5.5. Inside the acidic phagosomes (average pH ~ 5.9) of cells that have phagocytosed L. monocytogenes, LLO is selectively activated by maximizing activity at a pH of 5.5. Following the phagosome lysis by LLO, the bacterium breaks out into the cytosol, where it is able to grow intracellularly, and the toxin has reduced activity in the more basic cytosol. Thus, LLO permits L. monocytogenes to break out from the phagosomes into the cytosol without harming the plasma membrane of the infected cell, which allows the bacteria to live intracellularly, where they are sheltered from extracellular immune system factors such as the complement system and antibodies. LLO also brings about dephosphorylation of histone H3 and deacetylation of histone H4 in the early phases of infection, before entry of L. monocytogenes into the host cell. The pore-forming activity is not implicated in causing the histone modifications. The modifications of the histones affect the down regulation of genes encoding proteins involved in the inflammatory response. Therefore, LLO may be significant in subverting the host immune response to L. monocytogenes. At its NH2-terminus it possesses a 25 residues long typical signal sequence excited during the secretion process. Moreover, in its NH2-terminus there is also a 19 amino acids PEST- like sequence that may target this toxin for degradation. The PEST-like sequence found in LLO and is considered crucial for virulence, given that mutants lacking the sequence lysed the host cell. Nevertheless, contrary to PEST's supposed role in protein degradation, evidence implies that the PEST-like sequence may control LLO production in the cytosol rather than increase degradation of LLO.

MMP-3 enzyme is also known as Stromelysin-1or as Transin-1 which hydrolyzes natural collagen at physiological pH and temperature. It dissolves the intervertebral nucleus pulposus and annulus fibrosus of Herniated Lumbar Intervertebral Disk . MMP-3 hydrolyzes components of the extracellular matrix like proteoglycan, laminin, fibronectin, gelatin and collagen types III, IV and IX. It also activates pro-MMP-9 and pro-MMP-8 and superactivates plasmin activated MMP-1. MMP-3 is secreted as a latent proenzyme and is activated by a variety of proteinases, e.g. plasmin, trypsin, chymotrypsin, cathepsin G or human neutrophil elastase. MMP-3 was found to be capable of activating the precursor of IL1-beta.