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P450 Oxidoreductase, also known as POR is a flavoprotein which contributes electrons to all microsomal P450 enzymes. POR is localized to the endoplasmic reticulum, where it is also capable of transfering electrons to heme oxygenase as well as cytochrome b5. POR is structurally related to two separate flavoprotein families; first one is ferredoxin nucleotide reductase and the second flavodoxin.

PDE6H belongs to the rod/cone cGMP-PDE gamma subunit family, which selectively catalyze the hydrolysis of 3 cyclic phosphate bonds in adenosine and/or guanine 3,5 cyclic monophosphate (cAMP and/or cGMP). This family regulates the cellular levels, localization and duration of action of these second messengers by controlling the rate of their degradation. PDE6H is the inhibitory (or gamma) subunit of the cone-specific cGMP phosphodiesterase, which is atetramer composed of two catalytic chains (alpha and beta), and two inhibitory chains (gamma). PDE6H is particularly expressed in the retina, and is implicated in the transmission and amplification of the visual signal. Mutations in PDE6H have been associated with retinal cone dystrophy type 3A.

PRTN3 is a polymorphonuclear leukocyte serine protease which degrades elastin, fibronectin, laminin, vitronectin, and collagen types I, III, and IV (in vitro) and causes emphysema once managed by tracheal insufflation to hamsters.

Procollagen C-endopeptidase enhancer 1, also known as PCOLCE binds to the C-terminal propeptide of type I procollagen and enhances procollagen C-proteinase activity. In addition, C-terminal processed part of PCPE (CT-PCPE) has a metalloproteinase inhibitory activity. Among the diseases which are associated with PCOLCE: bone fracture & oculopharyngeal muscular dystrophy.

Matrix metalloproteinases are a family of zinc and calcium-dependent endopeptidases that break down extracellular matrix proteins. The MMP9 is secreted as a 92kDa zymogen. Cleavage of ProMMP-9 results in the active enzyme, having a molecular weight of approximately 82kDa. MMP9 is composed of the following domains: a gelatin-binding domain consisting of three fibronectin type II units, a catalytic domain containing the zinc-binding site, a proline-rich type V collagen-homologous domain and a hemopexin-like domain. MMP9 is produced by the several cell types: monocytes, macrophages, neutrophils, keratinocytes, fibroblasts, osteoclasts and endothelial cells. MMP9 is involved in inflammatory responses, tissue remodeling, wound healing, tumor growth and metastasis. MMP9 may also play an important part in local proteolysis of the extracellular matrix and in leukocyte migration, as well as in bone osteoclastic resorption. MMP9 cleaves type IV and type V collagens into large C-terminal three qu

Thyroid Peroxidase (TPO) represents one of the main autoantigenic targets in autoimmune thyroid disease of humans. Its identity with the formerly so-called `microsomal antigen` has been shown several years ago. As an integral membrane glycoprotein it is restricted to the apical plasma membrane of the follicular epithelial cells and comprises two identical subunits of approx. 100 kDa molecular weight. The hemoprotein TPO plays a key role in the thyroid hormone biosynthesis by catalysing both the iodination of tyrosyl residues and the coupling of iodotyrosyl residues in thyroglobulin (TG) to form precursors of the thyroid hormones T4 and T3.

Myeloperoxidase is an important enzyme used by granulocytes during phagocytic lysis of foreign particles engulfed. In normal tissues and in a variety of myeloproliferative disorders myeloid cells of both neutrophilic and eosinophilic types, at all stages of maturation, exhibit strong cytoplasmic reactivity for MPO. Erythroid precursors, megakaryocytes, lymphoid cells, mast cells, and plasma cells are nonreactive. MPO is not observed in the neoplastic cells of a wide variety of epithelial tumors and sarcomas. MPO is useful in differentiating between myeloid and lymphoid leukemias.

MPI is a member of the mannose-6-phosphate isomerase type 1 family. Although MPI is expressed in all tissues, it can be found more abundantly in heart, brain and skeletal muscle. Localized to the cytoplasm, MPI exploits zinc as a cofactor and catalyzes the interconversion of fructose-6-phosphate and mannose-6-phosphate. Mutations in the MPI gene are the cause of carbohydrate-deficient glycoprotein syndrome, type Ib.

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.

Treponema pallidum is a gram-negative spirochaete bacterium and is considered to be metabolically crippled. There are at least four known subspecies: T. pallidum pallidum, T. pallidum pertenue, T. pallidum carateum and T. pallidum endemicum. The helical structure of T. pallidum pallidum allows it to move in a corkscrew motion through viscous mediums such as mucus. Treponema pallidum sub sp. pallidum has one of the smallest bacterial genomes at 1.14 million base pairs (Mb) and has limited metabolic capabilities, reflecting its adaptation through genome reduction to the rich environment of mammalian tissue.

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.

Amine Oxidase Copper Containing 3 , also referred to AOC3, a copper amine oxidase with a topaquinone cofactor.
AOC3 is a cell adhesion protein which participates in recirculation & extravasation of lymphocyte by mediating the binding of lymphocytes to peripheral lymph node vascular endothelial cells in an L-selectin independent fashion.
Amine Oxidase Copper Containing 3 acts in adipogenesis.
The protein catalyzes the oxidative deamination of small primary amines such as methylamine, benzylamine & aminoacetone in a reaction that produces an aldehyde, ammonia and H2O2.

Thyroid Peroxidase (TPO) represents one of the main autoantigenic targets in autoimmune thyroid disease of humans. Its identity with the formerly so-called `microsomal antigen` has been shown several years ago. As an integral membrane glycoprotein it is restricted to the apical plasma membrane of the follicular epithelial cells and comprises two identical subunits of approx. 100 kDa molecular weight. The hemoprotein TPO plays a key role in the thyroid hormone biosynthesis by catalysing both the iodination of tyrosyl residues and the coupling of iodotyrosyl residues in thyroglobulin (TG) to form precursors of the thyroid hormones T4 and T3.

Inorganic pyrophosphatase (ppa) is a member of the Ppase family. PPA is an enzyme which catalyzes the conversion of one molecule of pyrophosphate to two phosphate ions. Since this is a highly exergonic reaction, it can therefore be coupled to unfavorable biochemical transformations in order to drive these transformations to completion. The role of the PPA enzyme is a critical one in the lipid metabolism (including lipid synthesis and degradation), calcium absorption and bone formation, DNA synthesis, as well as other biochemical transformations.

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.

PDIA3 is an enzyme that belongs to the endoplasmic reticulum and interacts with lectin chaperones calreticulin and calnexin to modulate folding of newly synthesized glycoproteins. PDIA3 has protein disulfide isomerase activity. Complexes of lectins and PDIA3 mediate protein folding by promoting formation of disulfide bonds in their glycoprotein substrates. PDIA3 is expressed in the lumbar spinal cord from rats submitted to peripheral lesion during neonatal period. PDIA3 interacts with thiazide-sensitive sodium-chloride cotransporter in the kidney and is induced by glucose deprivation. PDIA3 is part of the major histocompatibility complex (MHC) class I peptide-loading complex (TAP1), which is important for formation of the final antigen conformation and export from the endoplasmic reticulum to the cell surface.

PAPSS1 is a bifunctional enzyme with APS kinase and ATP sulfurylase activity. PAPSS1 facilitates two stages in the sulfate activation pathway, yielding 3'-phosphoadenylylsulfate (PAPS). Additionally, PAPSS1 takes part in the biosynthesis of sulfated L-selectin ligands in endothelial cells.

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 low molecular 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.

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.

Pin 1 is a peptidyl-prolyl cis/trans isomerase (PPIase) which interacts with NIMA and essential for cell cycle regulation Pin1 is nuclear PPIase containing a WW protein interaction domain, and is structurally and functionally related to Ess1/Ptf1, an essential protein in budding yeast. PPIase activity is necessary for Ess1/Pin1 function in yeast. Pin1 is thus an essential PPIase that regulates mitosis presumably by interacting with NIMA and attenuating its mitosis-promoting activity. Substrates of Pin1 include the mitotic regulators (Cdc25 phosphatase and NIMA, PLK I, Wee, and Myt1 kinases), several transcription factors like b-Catenin, c-Jun, and the tumor suppressor protein p53, and some specific proteins like the RNA Pol II, the cytoskeleton protein tau, and the G1/S protein Cyclin D1.

PRDX5 belongs to the peroxiredoxin family of antioxidant enzymes, which reduce hydrogen peroxide and alkyl hydroperoxides with reducing equivalents supplied through the thioredoxin system. PRDX5 has an antioxidant protective function in different tissues under normal conditions and during inflammatory processes. Peroxiredoxin-5 interacts with peroxisome receptor 1 and is involved in intracellular redox signaling. PRDX5 is involved in intracellular redox signaling. Peroxiredoxin-5 is a significant antioxidant protein of lung epithelial cells for its expression in the human lung increases during inflammation. PRDX5 expression is upregulated in osteoarthritis. PRDX5 may be significant in mitochondrial genome stability. Peroxiredoxin-5 has a protective role in human tendon cells against oxidative stress by reducing apoptosis and upholding collagen synthesis.

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.

PPA1 is a member of the PPase family. PPA1 catalyzes the conversion of one molecule of pyrophosphate to two phosphate ions. Many biochemical pathways use the hydrolysis of PPi to two phosphate ions to make the reactions permanently irreversible. A prominent illustration of this phenomenon is the inorganic pyrophosphatase catalyzation in the hydrolysis reaction at the beginning of lipid degradation. Inorganic pyrophosphatase provides the motivation for the activation of fatty acids destined for oxidation by stimulating the rapid hydrolysis of pyrophosphate.