Synthase

6-PyruvoylTetrahydropterin Synthase is part of the family of lyases, specifically those carbon-oxygen lyases acting on phosphates. 6-PyruvoylTetrahydropterin Synthase catalyzes the elimination of inorganic triphosphate from dihydroneopterin triphosphate, which is the second and irreversible step in the biosynthesis of tetrahydrobiopterin from GTP. Tetrahydrobiopterin, is a necessary cofactor and regulator of a range of enzyme activities, including enzymes involved in serotonin biosynthesis and NO synthase activity. Mutations in 6-PyruvoylTetrahydropterin Synthase gene result in hyperphenylalaninemia.

Uroporphyrinogen III synthase (UROS) is an enzyme involved in the 4th step of porphyrin metabolism and in the conversion of hydroxymethyl bilane into uroporphyrinogen III. Defects in the UROS protein can cause molecular lesions which lead to the autosomal recessive Gunther disease, otherwise known as congenital erythropoietic porphyria (CEP).

PTGES3 takes part as a cochaperone and is involved in signal transduction.
PTGES3 is a molecular chaperone that localizes to genomic response elements in a hormone-dependent manner and disrupts receptor-mediated transcriptional activation, by promoting disassembly of transcriptional regulatory complexess. PTGES3 is necessary for appropriate functioning of the glucocorticoid and other steroid receptors.
PTGES3 localizes to genomic response elements in a hormone-dependent method and disrupts receptor-mediated transcriptional activation, by promoting disassembly of transcriptional regulatory complexes.

PTGES2 is a membrane-associated prostaglandin E synthase, which catalyzes the conversion of prostaglandin H2 to prostaglandin E2. Additionally, PTGES2 activates the transcription regulated by a gamma-INF-activated transcription element. PTGES2 is widely expressed- in the heart, including apex, inter-ventricular septum, both atria and ventricles, but not in the aorta. PTGES2 is also expressed in fetal heart. PTGES2 is detected in various regions of the brain: cerebellum; occipital, frontal and parietal lobes. It is also expressed in the lymph nodes, skeletal muscle, kidney and trachea, but not in the thymus or lung. PTGES2 is overexpressed in colorectal cancer.

Prostaglandin-H2 D-isomerase (PTGDS) is a glutathione-independent prostaglandin D synthase which catalyzes the conversion of prostaglandin H2 (PGH2) to postaglandin D2 (PGD2). PTGDS is may have vital roles in both maturation and maintenance of the central nervous system and male reproductive system. PTGDS is the most abundant protein in the cerebral spinal fluid and recent evidence suggests that PTGDS acts as a beta-amyloid chaperone and may play a role in the deposition of Ab plaques in Alzheimer’s disease.

TSTA3 is a NADP(H)-binding protein. TSTA3 catalyzes the two-step epimerase and the reductase reactions in GDP-D-mannose metabolism, converting GDP-4-keto-6-D-deoxymannose to GDP-L-fucose. GDP-L-fucose is the substrate of numerous fucosyltransferases that take part in the expression of several glycoconjugates, including blood group ABH antigens and developmental adhesion antigens.
Mutations in TSTA3 result in leukocyte adhesion deficiency, type II.

GGPS1 is PART of the prenyltransferase family. GGPS1 is widely expressed in testis, heart and skeletal muscle, GGPS1 is localized in the cytoplasm and catalyzes the formation of geranylgeranyl pyrophosphate, a precursor of geranylgeranylated proteins and carotenoids. GGPS1 is a significant enzyme that is responsible for the C20-prenylation of proteins and for the regulation of a nuclear hormone receptor.

Phenylalanyl-tRNA synthetase 2 mitochondrial (FARS2) is a member of the class II aminoacyl- tRNA synthetase family. FARS2 is a mitochondrial matrix protein. FARS2 when acting as a monomer, catalyzes the ATP-dependent conversion of L-phenylalanine and tRNA (Phe) to L-phenlalanyltRNA (Phe), an event which is vital for proper translation and protein expression.

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.

OXSM, a beta-ketoacyl synthetase, is essential for elongation of fatty acid chains in the mitochondria. Alternatively spliced transcript variants were found.

SRM is an enzyme which catalyzes the transfer of the propylamine group from S-adenosylmethioninamine to putrescine in the biosynthesis of spermidine. The polyamines putrescine, spermine and spermidine are ubiquitous polycationic mediators of cell growth and differentiation. The SRM protein is one of four enzymes in the polyamine-biosynthetic pathway and completes the final step of spermidine biosynthesis.

ATP synthase subunit O (ATP5O) localizes to the mitochondria and catalyzes ATP synthesis. ATP5O is a component of the F-type ATPase found in the mitochondrial matrix. F-type ATPases are composed of a catalytic core and a membrane proton channel. ATP5O seems to be part of the connector connecting these two components and may be involved in transmission of conformational changes or proton conductance.

F-ATPase delta (ATP5D) catalyzes ATP synthesis, employing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation. ATP synthase is composed of 2 linked multi-subunit complexes: F1-the soluble catalytic core and Fo- the membrane-spanning component, which comprise the proton channel. The catalytic portion of mitochondrial ATP synthase consists of five different subunits (alpha, beta, gamma, delta, and epsilon) assembled with a stoichiometry of 3 alphas, 3 betas, and a single representative of the other three. The proton channel consists of three main subunits-a, b, c. ATP5D is the delta subunit of the catalytic core.

ASS1 is involved in the urea cycle, which is a sequence of chemical reactions that is localized in liver cells. The urea cycle processes excess nitrogen that is generated as the body uses proteins. The surplus nitrogen is used to create a molecule called urea, which is excreted from the body in urine.

Asparagine synthetase (ASNS) is a cytoplasmic enzyme that turns aspartate toasparagine and functions mostly in mammalian organs. ASNS is responsible for cell growthand its mRNA content is associated with changes in the cell cycle. ASNS may also play a role as a biomarker for ovarian cancer.

Spermine synthase (SMS) is amember of the spermidine/spermine synthase family. SMS is an enzyme which converts spermidine into spermine. The SMS enzyme is essential for normal viability, growth and fertility involved in polyamine metabolism. Defects in the SMS gene are the cause of Snyder-Robinson syndrome (SRS), also known as X-linked mental retardation Snyder-Robinson type. SRS is categorized by moderate intellectual deficit, hypotonia, an unsteady gait, osteoporosis, kyphoscoliosis and facial asymmetry, its transmission is X-linked recessive.

DHPS is vital for the first step of hypusine biosynthesis. DHPS catalyzes the NAD-dependent transfer of the butylamine moiety of spermidine to the epsilon-amino group of a specific lysine residue of the EIF5A precursor protein to form the intermediate deoxyhypusine residue.

NANS is a 359 amino acid protein that contains one AFP (antifreeze proteins)-like domain and functions in the biosynthesis of sialic acids. The ubiquitously expressed NANS enzymatically catalyzes the H2O-dependent formation of N-acetylneuraminic acid (Neu5Ac) and 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN), both of which are sialic acids. NANS uses N-acetylmannosamine 6-phosphate as a substrate for Neu5Ac synthesis and mannose 6-phosphate as a substrate for KDN synthesis.

Hematopoietic Prostaglandin D Synthase (HPGDS) belongs to the sigma class glutathione-S-transferase family. The HPGDS enzyme catalyzes the conversion of PGH2 to PGD2 and has a role in the production of prostanoids in the immune system and mast cells. The presence of the HPGDS enzyme can be utilized to identify the differentiation stage of human megakaryocytes. Furthermore, HPGDS is a prostaglandin involved in smooth muscle contraction/relaxation and an effective inhibitor of platelet aggregation, and the conjugation of glutathione with a extensive range of aryl halides and organic isothiocyanates. In addition, HPGDS displays low glutathione-peroxidase activity towards cumene hydroperoxide. HPGDS is expressed in a number of megakaryocytic cell lines but not in platelets. HPGDS is highly expressed in the adipose tissue, macrophages and placenta; however it is expressed at lower levels in the lung, heart, lymph nodes, appendix, bone marrow and fetal liver.

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.

SEPSECS catalyzes the last step of sec synthesis by converting O-phosphoseryl-tRNA(sec) to selenocysteinyl-tRNA(sec) using selenophosphate as the selenium donor. Furthermore, SEPSECS protein is considered a specific marker of autoimmune hepatitis.

SEPSECS catalyzes the last step of sec synthesis by way of converting O-phosphoseryl-tRNA(sec) to selenocysteinyl-tRNA(sec) using selenophosphate as the selenium donor. Furthermore, SEPSECS protein is considered a specific marker of autoimmune hepatitis.

Porphobilinogen deaminase (HMBS) belongs to the hydroxymethylbilane synthase superfamily. HMBS is a cytoplasmic enzyme found in the heme synthesis pathway. HMBS is the 3rd enzyme of the heme biosynthetic pathway and catalyzes the head to tail condensation of 4 porphobilinogen molecules into the linear hydroxymethylbilane. HMBS gene mutations cause errors in pyrrole metabolism which in turn lead to the autosomal dominant disease acute intermittent porphyria.

Citrate synthase also known as CS is a Krebs tricarboxylic acid cycle enzyme which catalyzes the synthesis of citrate from oxaloacetate and acetyl coenzyme A. CS is present in almost all cells capable of oxidative metabolism. CS is nuclear encoded and transported into the mitochondrial matrix, where the mature form is found. The diseases related to CS are: critical illness polyneuropathy and mitochondrial cardiomyopathy.