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Thymine-DNA glycosylase (TDG) is a member of the TDG/mug DNA glycosylase family.
TDG is a nuclear protein that fixes G/T mismatches to G/C pairs by hydrolyzing the carbon-nitrogen bond between the sugar-phosphate backbone of the DNA and the mispaired thymin. In addition, TDG removes uracil and 5-bromouracil from mispairings with guanine. The TDG enzyme has an essential role in cellular defense against genetic mutation triggered by the spontaneous deamination of 5-methylcytosine and cytosine.

ACAT2 enzyme participates in lipid metabolism. ACAT2 takes part in lipoprotein assembly, catalyzing cholesterol esterification in mammalian cells. ACAT2 is an integral membrane protein that localizes to the endoplasmic reticulum of human intestinal cells. ACAT2 deficiency contributes to severe mental retardation and hypotonus.

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.

Guanosine-3',5'-bis(diphosphate)-pyrophosphohydrolase MESH1 (HDDC3) contains an active site for ppGpp hydrolysis and a conserved His-Asp-box motif for Mn(2+) binding. In accordance with its structure, HDDC3 effectively catalyzes the hydrolysis of guanosine 3',5'-diphosphate (ppGpp) both in vitro and in vivo. In addition, HDDC3 suppresses SpoT-deficient lethality and RelA-induced delayed cell growth in bacteria.

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.

PRCP is a plasma protein which takes part in the cleavage of C-terminal amino acids linked to proline in proteinfor example angiotensin-2 & 3 at acidic pHenvironment rather than at neutral pHwhich exhibit less activity. This cleavage is important since Angiotensin-2 takes part in regulation of blood pressure & electrolyte balance which is essential to hypertension.

BPGM is found at high concentrations in red blood cells where it binds to and decreases the oxygen affinity of hemoglobin. PGM deficiency increases the oxygen affinity of cells. BPGM is a multifunctional enzyme that catalyzes 2,3-DPG synthesis through its synthetase activity, and 2,3-DPG degradation using its phosphatase activity. BPGM has phosphoglycerate phosphomutase activity. Mutations in BPGM cause hemolytic anemia. BPGM catalyzes the reaction of EC 5.4.2.1 (mutase) and EC 3.1.3.13 (phosphatase), but with a reduced activity.

MMP-1 can break down a wide range of substrates including types I, II, III, VII, VIII, and X collagens as well as L-Selectin, pro-TNF, IL-1?, IGFBP-3, IGFBP-5, casein, gelatin, ?1 antitrypsin, myelin basic protein, pro-MMP2 and pro-MMP9. A significant function of MMP-1 is the degradation of fibrillar collagens in extracellular matrix remodeling. MMP-1 is expressed in fibroblasts, keratinocytes, endothelial cells, monocytes and macrophages. MMP1 can be divided into a number of distinct domains: a prodomain which is cleaved on activation, a catalytic domain containing the zinc binding site and a short hinge region with a carboxyl terminal domain. MMP1 is part of a cluster of MMP genes which localize to chromosome 11q22.3.

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.

Cystathionine gamma-lyase or cystathionase (CTH) is a member of the trans-sulfuration enzymes family. CTH is an enzyme which breaks down cystathionine into cysteine and alpha-ketobutyrate. The CTH catalyzes the last step in the transsulfuration pathway from methionine to cysteine. Glutathione synthesis in the liver is dependent upon the availability of cysteine. Mutations in the CTH gene cause cystathioninuria.

Growth-Hormone is a member of the somatotropin/prolactin family of hormones which play an important role in growth control. The gene, along with four other related genes, is located at the growth hormone locus on chromosome 17 where they are interspersed in the same transcriptional orientation; an arrangement which is thought to have evolved by a series of gene duplications. The five genes share a remarkably high degree of sequence identity. Alternative splicing generates additional isoforms of each of the five growth hormones, leading to further diversity and potential for specialization. This particular family member is expressed in the pituitary but not in placental tissue as is the case for the other four genes in the growth hormone locus. Mutations in or deletions of the gene lead to growth hormone deficiency and short stature.

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.

Carboxyl ester lipase also known as CEL, formely called cholesterol esterase or bile salt-stimulated lipase, is an enzyme with lipolytic capablity of hydrolyzing cholesteryl esters, tri-, di-, and mono- phospholipids, acylglycerol, ceramide and lysophospholipids. The carboxyl terminus of the enzyme controls enzymatic activity by creating hydrogen bonds with the surface loop to partlyshield the active site. The active catalytic site triad of serine-histidine-aspartate is centrally located in the enzyme structure and is partly covered by a surface loop. Bile salt binding to the loop domain set free the active site for accessibility by water-insoluble substrates. CEL is produced mainly in the pancreas and lactating mammary gland, thus the protein is also expressed in liver, macrophages, and in the vessel wall.

ARG1 catalyzes the hydrolysis of arginine to ornithine and urea. 2 isoforms of mammalian arginase exist which vary in their tissue distribution, subcellular localization, immunologic crossreactivity and physiologic role. ARG1 is a cytosolic enzyme and expressed widely in the liver as part of the urea cycle. Inherited deficiency of this ARG1 causes argininemia, which is an autosomal recessive disorder characterized by hyperammonemia.

Arginase-1 is part of the urea cycle, it catalyzes the hydrolysis of arginine to ornithine and urea. There are two isoforms of mammalian arginase which differ in their tissue location, subcellular localization, immunologic crossreactivity & physiologic role. Arginase-1is a cytosolic enzyme and expressed primarily in the liver tissue. Inherited deficiency in this enzyme may lead toargininemia, which is an autosomal recessive disease in which hyperammonemia is detected.

Inositol monophosphatase1 (IMPA1) is responsible for the provision of inositol essential for synthesis of phosphatidylinositol and polyphosphoinositides. IMPA1 has a central role in the phosphatidylinositol signaling pathway by catalyzing the hydrolysis of inositol monophosphates. IMPA1 has been recognized as the pharmacological target for lithium action in the brain. The IMPA1 enzyme has a magnesium-dependent phosphatase activity and is inhibited by therapeutic concentrations of lithium. Inhibition of inositol monophosphate hydroylosis and ensuing depletion of inositol for phosphatidylinositol synthesis may perhaps explain the anti-manic and anti-depressive effects of lithium administered to treat bipolar disorder.

TIMP2 belongs to the TIMP gene family. The proteins encoded by this gene family are natural inhibitors of the matrix metalloproteinases, a group of peptidases that take part in degradation of the extracellular matrix. Besides having an inhibitory role against metalloproteinases, the encoded protein has a exclusive part among TIMPfamily members in its capability to directly suppress the proliferation of endothelial cells. Consequently, the encoded protein is crucial to the conservation of tissue homeostasis by suppressing the production of quiescent tissues as an answer to angiogenic factors, and by inhibiting protease activity in tissues undergoing renovation of the extracellular matrix.

DARS uses a 2 step reaction to catalyze the specific attachment of an amino acid to its cognate tRNA: the amino acid (AA) is first activated by ATP to form AA-AMP and then transferred to the acceptor end of the tRNA.

Plasma protease C1 inhibitor (SERPING1) is a part of the serpin superfamily of serine protease inhibitors. SERPING1 plays an important role in regulating activation of both the complement and contact systems. That isdue to the fact that SERPING1 regulates the activation of complement factor C1 in addition to the activity of activated C1 by coupling with the active catalytic site at the light chains of C1r and C1s. SERPING1 insufficiency results in hereditary angioedema, which is characterized by recurrent episodes of localized angioedema of the skin, gastrointestinal mucosa or upper respiratory mucosa.

SUMF1 is a part of the SUMF protein family. SUMF1 catalyzes the hydrolysis of sulfate esters by oxidizing a cysteine residue in the substrate sulfatase to an active site 3-oxoalanine residue called C-alpha-formylglycine. Mutations in this gene will cause multiple sulfatase deficiency meaning a lysosomal storage disorder.

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.

Angiotensin is an oligopeptide in the blood that causes vasoconstriction, increased blood pressure, and release of aldosterone from the adrenal cortex. It is a powerful dipsogen. It is derived from the precursor molecule angiotensinogen, a serum globulin produced in the liver. It plays an important role in the renin-angiotensin system.
The protein encoded by this gene, pre-angiotensinogen or angiotensinogen precursor, is expressed in the liver and is cleaved by the enzyme renin in response to lowered blood pressure. The resulting product, angiotensin I is then cleaved by angiotensin converting enzyme (ACE) to generate the physiologically active enzyme angiotensin II. The protein is involved in maintaining blood pressure and in the pathogenesis of essential hypertension and preeclampsia.

Glutaminyl-Peptide Cyclotransferase, also known as QPCT is a member of the glutaminyl-peptide cyclotransferase family. QPCT is responsible for the biosynthesis of pyroglutamyl peptides. Furthermore, QPCT is partial against acidic and tryptophan residues adjacent to the N-terminal glutaminyl residue and a lack of importance of chain length following the second residue. QPCT catalyzes N-terminal pyroglutamate formation, also in vitro, it catalyzes pyroglutamate formation of N-terminally truncated form of APP amyloid-beta peptides [Glu-3]-beta-amyloid.