Search results

Mannoside Acetylglucosaminyltransferase 2 (MGAT2) is a golgi enzyme catalyzing an vital step in the conversion of oligomannose to complex N-glycans. MGAT2 enzyme has the characteristic glycosyltransferase domains: a short N-terminal cytoplasmic domain, a hydrophobic non-cleavable signal-anchor domain, and a C-terminal catalytic domain. MGAT2 gene mutations may lead to carbohydrate-deficient glycoprotein syndrome, type II.

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).

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.

Hydroxymethylglutaryl-CoA lyase (HMGCL) is a mitochondrial matrix protein which is a member of the HMG-CoA lyase family. HMGCL is a homodimer and participates in leucine catabolism and ketogenesis, the hepatic synthesis of ketone bodies which, during fasting, provides a major source of energy for the heart, brain and kidney. More precisely, HMGCL catalyzes the final step of these processes, the cleavage of 3-hydroxy-3-methylglutaryl-CoA to acetoacetic acid and acetyl-CoA.

Hydroxymethylglutaryl-CoA lyase (HMGCL) is a mitochondrial matrix protein which is a member of the HMG-CoA lyase family. HMGCL is a homodimer and participates in leucine catabolism and ketogenesis, the hepatic synthesis of ketone bodies which, during fasting, provides a major source of energy for the heart, brain and kidney. More precisely, HMGCL catalyzes the final step of these processes, the cleavage of 3-hydroxy-3-methylglutaryl-CoA to acetoacetic acid and acetyl-CoA.

METTL21A, which is a part of the methyltransferase superfamily, is a Protein-lysine methyltransferase that in vitro methylates HSPA1, HSPA5 and HSPA8.

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.

DDX39A which is a part of the DEAD box protein family is characterized by the conserved motif Asp-Glu-Ala-Asp. This pattern is implicated in a various cellular processes involving alteration of RNA secondary structure, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Several members of the DEAD box protein family are taking part in embryogenesis, spermatogenesis, and cellular growth and division.

ARPC5 is a 151 amino acid subunit of the Arp2/3 complex. ARPC5 is believed to have a role in maintaining the integrity of Arp2/3. ARPC5 is a substrate for MAPKAPK-2 which, via phosphorylation of ARPC5, may participate in Arp2/3 regulatory functions and remodeling of the Actin cytoskeleton.

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.

PCMT1 enzyme catalyses the methyl esterification of L-isoaspartyl and D-aspartyl residues in peptides and proteins that result from spontaneous decomposition of normal L-aspartyl and L-asparaginyl residues. PCMT1 is involved in the repair and/or degradation of damaged proteins.

Branched-chain ?-keto acid dehydrogenase E1 component ? chain (BCKDHA) is a member of the BCKDHA family. The BCKD (branched-chain alpha-keto acid dehydrogenase) complex is an inner mitochondrial enzyme complex which catalyzes the second major step in the catabolism of the branched-chain amino acids leucine, isoleucine, and valine. This complex consists of 3 catalytic components: a heterotetrameric (alpha2-beta2) branched-chain alpha-keto acid decarboxylase (E1), a dihydrolipoyl transacylase (E2), and a dihydrolipoamide dehydrogenase (E3). Mutations in the BCKDHA gene result in maple syrup urine disease, type IA.

AKR7A3, takes part in the detoxification of aldehydes and ketones. AKR7A3 reduces the dialdehyde protein-binding form of aflatoxin B1 (AFB1) to the non-binding AFB1 dialcohol. AKR7A3 participates in protection of liver against the toxic and carcinogenic effects of AFB1, a potent hepatocarcinogen.

GARS is an (alpha)2 dimer which is a member of the class II family of tRNA synthetases. GARS is a glycyl-tRNA synthetase, one of the aminoacyl-tRNA synthetases which charge tRNAs with their cognate amino acids. GARS catalyzes the attachment of glycine to tRNA(Gly). In addition, GARS is able to produce diadenosine tetraphosphate (Ap4A), which is a universal pleiotropic signaling molecule required for cell regulation pathways, by direct condensation of two ATPs. GARS has been demonstrated to be a target of autoantibodies in the human autoimmune diseases, polymyositis or dermatomyositis.

Hexokinases phosphorylate glucose to produce glucose-6-phosphate, thus committing glucose to the glycolytic pathway. Hexokinase1 encodes a ubiquitous form of hexokinase which localizes to the outer membrane of mitochondria. Mutations in this gene have been associated with hemolytic anemia due to hexokinase deficiency. Alternative splicing of HXK1 results in five transcript variants which encode different isoforms, some of which are tissue-specific. Each isoform has a distinct N-terminus; the remainder of the protein is identical among all the isoforms. A sixth transcript variant has been described, but due to the presence of several stop codons, it is not thought to encode a protein.

UBE2K belongs to the ubiquitin-conjugating enzymes family which take part in many cellular processes such as selective protein degradation, DNA repair, cell cycle control, and sporulation. In this mechanism, the ATP-coupled activation and subsequent ligation of ubiquitin are catalyzed by separate enzymes functionally linked by ubiquitin carrier protein UBC1. In addition, UBE2K is involved in Alzheimer's disease, Huntington's disease and antigen processing through its interaction with amyloid-?, huntingtin, and MHC-heavy chain proteins.

Autophagy Related 3 (ATG3) is a conjugating enzyme essential for the cytoplasm to vacuole transport (Cvt), autophagy, and mitochondrial homeostasis. ATG3 is localizes to the cytoplasm and is expressed in tissues with predominant levels found in kidney, placenta, liver, heart and skeletal muscle. ATG3 catalyzes a reaction which is necessary for autophagy. That reaction is the formation of the Atg8-phosphatidylethanolamine (ATG-PE) conjugate.

Adenosine deaminase-like protein (ADAL) is a putative nucleoside deaminase. ADAL catalyzes the hydrolytic deamination of adenosine or some similar substrate and has a role in purine metabolism.

Serine/threonine-protein kinase 16 (STK16) is a membrane-associated protein kinase which phosphorylates on serine and threonine residues. STK16 is involved in secretory vesicle trafficking or intracellular signaling. Furthermore, the STK16 protein may have a role in regulating stromal-epithelial interactions which occur during ductal morphogenesis in the mammary gland. STK16 can autophosphorylate on Tyr residue; it is however unclear whether STK16 has tyrosine-protein kinase toward other proteins. STK16 may also be involved in TGF-beta signaling.

AKR1C4 is a member of the aldo/keto reductase superfamily that has over 40 known enzymes and proteins. AKR1C4 enables the conversion of aldehydes and ketones to their corresponding alcohols by using NADH and/or NADPH as cofactors. AKR1C4 takes part in the bioreduction of chlordecone, a toxic organochlorine pesticide, to chlordecone alcohol in liver.

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.

SIRT3 is a member of a family of proteins called Sirtuin. Proteins of the Sirtuin family are characterized by a Sirtuin core domain and grouped into four classes. The roles of human Sirtuins are numerous and are important in aging prosseses, stress resistance and metabolic regulation. SIRT3 shows NAD+-dependent deacetylase activity in the mitochondria. Over-expression of SIRT3 causes increased levels of the mitochondrial uncoupling protein 1. Also, in certain breast cancers the levels of SIRT3 protein are found to be extremely high.

Alcohol dehydrogenase 1A (ADH1A) is a member of the alcohol dehydrogenase family. ADH1A has a key role in ethanol metabolism. ADH1A along with coenzyme NAD catalyzes the reversible conversion of organic alcohols to ketones or aldehydes. The physiologic function of ADH1A in the liver is the elimination of ethanol formed by microorganisms in the intestinal tract. ADH1A is monomorphic and predominant in fetal and infant livers, growing to be less active in gestation and only weakly active during adulthood.

CysH (Phosphoadenosine phosphosulfate reductase) is a member of the PAPS reductase family, specifically those acting on a sulfur group of donors with a disulfide as acceptor. The 3 substrates of the CysH enzyme are adenosine 3',5'-bisphosphate, sulfite, and thioredoxin disulfide, whereas its two products are 3'-phosphoadenylyl sulfate and thioredoxin.