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Guanosine monophosphate reductase (GMPR) catalyzes the irreversible NADPH-dependent deamination of GMP to IMP. GMPR acts in the conversion of nucleobase, nucleoside and nucleotide derivatives of G to A nucleotides, and in upholding the intracellular balance of A and G nucleotides. In addition, the GMPR protein functions in the re-utilization of free intracellular bases and purine nucleosides.

DNA polymerase beta (POLB) is a member of the DNA polymerase type-X family. In eukaryotic cells, POLB performs base excision repair necessary for DNA maintenance, replication, recombination, and drug resistance. POLB has 2 separate domains; the larger is the polymerase domain itself, whereas a small basic N-terminal domain contains an AP lyase activity which excises the abasic sugar-phosphate residue at the strand break. POLB fills single nucleotide gaps in DNA produced by the base excision repair pathway of mammalian cells. POLB overexpression, as seen in some human tumors, could convene an increase in spontaneous mutagenesis.

GOT1 is a pyridoxal phosphate-dependent enzyme which exists in cytoplasmic and mitochondrial forms, GOT1 and GOT2, which participate in amino acid metabolism and the urea and tricarboxylic acid cycles. Both enzymes are homodimeric and show close homology.

ST6GAL1 also known as ST6 Beta-Galactosamide Alpha-2,6-Sialyltranferase 1, is part of the glycosyltransferase family 29. ST6GAL1 is a type II membrane protein which catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates. Furthermore, ST6GAL1 is normally found in the Golgi however it can be proteolytically processed to a soluble form, ST6GAL1 is also involved in the generation of the cell-surface carbohydrate determinants as well differentiation antigens HB-6, CD75, and CD76.

Erythrocyte acylphosphatase (ACYP1) is a cytosolic enzyme which catalyzes the hydrolysis of the carboxyl-phosphate bond of acylphosphates. There are two acylphophatase isoenzymes: ACYP1 and ACYP2. These isoenzymes share 60% homology and have the same substrate specificity, even though ACYP1 has a higher catalytic activity than ACYP2.

PHOSPHO1 is involved in mineralization process & plays a role in bone and cartilage matrix mineralization.
PHOSPHO1 is expressed at sites of mineralization in bone and cartilage. Highly expressed in osteoblast cell line SaOS-2 which produces a mineralized matrix.
Orphan-1 is collagen type -2 is specific for cartilaginous tissues. Orphan1 is essential for the normal embryonic development of the skeleton, for linear growth and for the ability of cartilage to resist compressive forces.
Phosphoethanolamine (2-O3POCH2CH2NH3) is a key intermediate in the formation of cephalins, it is formed in liver and brain by phosphorylation of ethanolamine.
PHOSPHO2 and PHOSPHO1 suggest subtle differences in the charge distributions around the putative substrate entry site and in the location of potential H-bond donors.
PHOSPHO1 exhibits high specific phosphoethanolamine and phosphocholine phosphatase activities PHOSPHO1 is a phosphatase enzyme for which expression is upregulated in mineralizing cells. PHOSPHO1 has been implicated in the generation of Pi for matrix mineralization, a process central to skeletal development. PHOSPHO1 is a member of the haloacid dehalogenase (HAD) superfamily of Mg2+-dependent hydrolases. PHOSPHO1 exhibits high specific activities toward phosphoethanolamine (PEA) and phosphocholine (PCho).

Phosphomannomutase 1 (PMM1) is an enzyme involved in the synthesis of the GDP-mannose and dolichol-phosphate-mannose required for a number of critical mannosyl transfer reactions. PMM1 catalyzes the conversion between D-mannose 6-phosphate and D-mannose 1-phosphate which is a substrate for GDP-mannose synthesis. GDP-mannose is used for the synthesis of dolichol-phosphate-mannose, which is crucial for N-linked glycosylation and accordingly the secretion of several glycoproteins as well as for the synthesis of glycosyl-phosphatidyl-inositol (GPI) anchored proteins. Additionally, PMM1 may be responsible for the degradation of glucose-1,6-bisphosphate in ischemic brain.

Phospholipase A1 Member A (PLA1A) is a phospholipase which hydrolyzes fatty acids at the sn-1 position of phosphatidylserine and 1-acyl-2-lysophosphatidylserine. The secreted PLA1A protein hydrolyzes phosphatidylserine in liposomes. PLA1A hydrolyzes phosphatidylserine (PS) in the form of liposomes and 1-acyl-2 lysophosphatidylserine (lyso-PS), but not triolein, phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA) or phosphatidylinositol (PI). PLA1A isoform 2 hydrolyzes lyso-PS but not PS. The hydrolysis of lyso-PS in peritoneal mast cells activated by receptors for IgE leads to stimulation of histamine production.

Lysyl-tRNA synthetase (KARS) is a member of the class-II aminoacyl-tRNA synthetase family. KARS exists as both mitochondrial and cytoplasmic isoforms produced by alternative splicing, and believed to have a role in autoimmune diseases, such as polymyositis or dermatomyositis. The KARS protein functions to catalyze the aminoacylation of tRNAs by their corresponding amino acids, so linking amino acids with tRNA-contained nucleotide triplets.

LDHA catalyzes the conversion of L-lactate and NAD to pyruvate and NADH in the final step of anaerobic glycolysis. LDHA is localized primarily in muscle tissue and is part of the lactate dehydrogenase family. Mutations in LDHA have been linked to exertional myoglobinuria. LDH1 is decreased in essential thrombocythemia. LDHA is induced through a non-genomic pathway of estrogen action. Reduction in LDH-A activity results in stimulation of mitochondrial respiration and decrease of mitochondrial membrane potential.

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.

Cell division protein kinase 5 (CDK5) belongs to the cyclin-dependent kinase family. CDK5 is essential for appropriate development of the brain and in order to be activated CDK5 must link to CDK5R1 or CDK5R2. CDK5 doesn't need phosphorylation on the T loop so that binding with the activator is enough to activate the kinase. CDK5 is engaged in the processes of neuronal maturation and migration, phosphorylating the central intracellular adaptor of the reeling signaling chain.

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.

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.

Peptidase D, also known as PEPD, Is a part of the peptidase family. PEPD is involved in collagen metabolism due to the high level of iminoacids in collagen. PEPD recycles proline, and sets the pace for the production of collagen. PEPD is also parts dipeptides with a prolyl or hydroxyprolyl residue in the C-terminal position.

APRT is part of the purine/pyrimidine phosphoribosyltransferase family. APRT enzyme catalyzes the formation of AMP and inorganic pyrophosphate from adenine and 5-phosphoribosyl-1-pyrophosphate (PRPP). APRT produces adenine as a by-product of the polyamine biosynthesis pathway. A homozygous deficiency in APRT causes 2,8-dihydroxyadenine urolithiasis. APRT catalyzes a salvage reaction resulting in the formation of AMP.

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.

BDH1 belongs to the short-chain dehydrogenase/reductase gene family. BDH1 forms a homotetrameric lipid-requiring enzyme of the mitochondrial membrane and has a specific necessity for phosphatidylcholine for optimal enzymatic activity. BDH1 catalyzes the interconversion of acetoacetate and (R)-3-hydroxybutyrate, the 2 main ketone bodies formed during fatty acid catabolism.

3-Hydroxy-3-Methylglutaryl-CoA Synthase 1, also known as HMGCS1 is a member of the Belongs to the HMG-CoA synthase family. HMGCS1 condenses acetyl-CoA with acetoacetyl-CoA to form HMG-CoA, which is the substrate for HMG-CoA reductase.

NADH dehydrogenase (ubiquinone) 1 beta subcomplex subunit 9 (NDUFB9) which is a part of the complex I LYR family is localized to the internal mitochondrial membrane, as well as to the matrix side of the peripheral membrane. NDUFB9 serves as an accessory subunit of the multi-subunit mitochondrial membrane respiratory chain NADH dehydrogenase complex I. Complex I takes a crucial part in the transfer of electrons from NADH to the respiratory chain, a process which is vital for cellular respiration.

GMDS is a member of the GDP-mannose 4,6-dehydratase family. GMDS uses NADP as a cofactor to catalyze the conversion of GDP-mannose to GDP-4-keto-6-deoxymannose. Defects in the gene encoding GMDS cause TRAIL (tumor necrosis factor-related apoptosis-inducing ligand)-induced apoptosis.

NQO1 belongs to the NAD(P)H dehydrogenase (quinone) family and encodes a cytoplasmic 2-electron reductase. NQO1 acts as an imperative part of cellular antioxidant defense by detoxifying quinines therefore preventing the formation of reactive oxygen species. It seems that NQO1 serves as a quinone reductase relating to conjugation reactions of hydroquinons involved in detoxification pathways in addition to biosynthetic processes such as the vitamin K-dependent gamma-carboxylation of glutamate residues in prothrombin synthesis. Altered NQO1 expression is seen in many tumors and also linked to Alzheimer’s disease. NQO1 gene mutations are linked to tardive dyskinesia which is an increased risk of hematotoxicity after exposure to benzene, and susceptibility to various forms of cancer.

P4HB is a multifunctional and highly abundant enzyme that is part of the protein disulfide isomerase family. When present as a tetramer consisting of two alpha and two beta subunits, P4HB has a role in hydroxylation of prolyl residues in preprocollagen. P4HB is a disulfide isomerase containing two thioredoxin domains that catalyze the formation, breakage and rearrangement of disulfide bonds.

HNMT is located in the cytosol and uses S-adenosyl-L-methionine as the methyl donor. In the mammal’s brain,N(tau)-methylation controls the neurotransmitter activity of histamine since diamine oxidase is not located in the central nervous system. A well known genetic polymorphism influences the activity levels of HNMT gene product in red blood cells. HNMT inactivates histamine by n-methylation. HNMT is involved in degrading histamine and in regulating the airway response to histamine. Histamine is involved in regulation and modulation of immune response through the stimulation of four distinct subtypes of receptors, H1, H2, H3, and H4, that present on the target cells. Histamine is inactivated by the histamine-metabolizing enzyme HNMT in bronchus, kidney, and the central nervous system.