Oxygenase

HAAO is a monomeric cytosolic protein which is a member of intramolecular dioxygenases family containing nonheme ferrous iron. The HAAO protein catalyzes the synthesis of quinolinic acid (QUIN) from 3-hydroxyanthranilic acid. QUIN is an excitotoxin whose toxicity is facilitated by its ability to activate glutamate N-methyl-D-aspartate receptors. Amplified cerebral levels of QUIN may contribute to the pathogenesis of neurologic and inflammatory disorders. HAAO is widely distributed in peripheral organs, such as liver and kidney, and is also present in low amounts in the central nervous system.

Luciferase is a general term for the class of oxidative enzymes used in bioluminescence and is distinct from a photoprotein. Luciferase catalyzes a bioluminescent reaction which involves the substrate luciferin as well as Mg2+ and ATP, produces green light with a wavelength of 562 nm. Luciferase from firefly is broadly used as a reporter for studying gene regulation and function, and for pharmaceutical screening.

Luciferase is a general term for the class of oxidative enzymes used in bioluminescence and is distinct from a photoprotein. Luciferase catalyzes a bioluminescent reaction which involves the substrate luciferin as well as Mg2+ and ATP, produces green light with a wavelength of 562 nm. Luciferase from firefly is broadly used as a reporter for studying gene regulation and function, and for pharmaceutical screening.

CDO1 (Cysteine dioxygenase) is a mammalian non-heme iron enzyme that initiates a number of significant metabolic pathways associated with pyruvate and several sulfurate compounds including sulfate, hypotaurine and taurine. CDO1 catalyzes the conversion of L-cysteine to cysteine sulfinic acid (cysteine sulfinate) by incorporation of dioxygen. CDO1 is a vital regulator of cellular cysteine concentrations and has an essential role in maintaining the hepatic concentration of intracellular free cysteine within a proper narrow range. CDO1 is able to alter intracellular cysteine levels and glutathione levels. CDO1 is highly expressed in the liver and placenta. On the other hand CDO1 has a low expression in heart, brain and pancreas. CDO1 can also be detected in hepatoblastoma HepG2 cells.

TDO2 is a ferrous heme enzyme that catalyzes the first and rate-limiting step in the kynurenine pathway which is the major pathway of tryptophan metabolism. TDO2 integrates oxygen into the indole moiety of tryptophan. TDO2 has broad specificity towards tryptamine and derivatives including D- and L-tryptophan, 5-hydroxytryptophan and serotonin.

Indoleamine 2,3-Dioxygenase 1 (IDO1) catalyzes the primary and rate-limiting stage in tryptophan catabolism to N-formyl-kynurenine. IDO1 affects on various tryptophan substrates including D-tryptophan, and serotonin and is expressed in dendritic cells, monocytes, and macrophages. IDO1 takes part in a range of pathophysiological processes like neuropathology, antimicrobial and antitumor defense, immunoregulation, and antioxidant activity. IDO1 regulates T-cell behavior by its pericellular catabolization of the necessary amino acid tryptophan.

Indoleamine 2,3-Dioxygenase 1 (IDO1) catalyzes the primary and rate-limiting stage in tryptophan catabolism to N-formyl-kynurenine. IDO1 affects on various tryptophan substrates including D-tryptophan, and serotonin and is expressed in dendritic cells, monocytes, and macrophages. IDO1 takes part in a range of pathophysiological processes like neuropathology, antimicrobial and antitumor defense, immunoregulation, and antioxidant activity. IDO1 regulates T-cell behavior by its pericellular catabolization of the necessary amino acid tryptophan.

HPGD is the essential enzyme of prostaglandin degradation. 15-PGDH protein strongly decreases the biologic activity of these molecules by catalyzing the oxidation of the 15-hydroxyl group of prostaglandins to a keto group. GDH1 is involved in numerous physiologic and cellular processes, for instance inflammation.

4-Hydroxyphenylpyruvate Dioxygenase Isoform-1 is an Fe-containing enzyme, which catalyzes the second reaction in the catabolism of tyrosine the conversion of 4-hydroxyphenylpyruvate to homogentisate. Present as a homodimer, HPD uses zinc as a cofactor to catalyze the third step in the conversion of L-phenylalanine to fumarate and acetoacetic acid. Flaws in the gene encoding HPD result in tyrosinemia type 3 and hawkinsinuria, two inborn defects of metabolism which are related to a number of symptoms, like mental retardation and seizures and hair and urine abnormalities.

HMOX2 cleaves the heme ring at the alpha methene bridge to form biliverdin. Biliverdin is subsequently transferred to bilirubin by biliverdin reductase. Under physiological conditions, the activity of HMOX2 is highest in the spleen, where senescent erythrocytes are sequestrated and destroyed. HMOX2 participates in the production of carbon monoxide in the brain where it operates as a neurotransmitter. HMOX2 is an essential enzyme in heme catabolism and is involved in cellular response to oxidative stress.

HMOX1 cleaves the heme ring at the alpha methene bridge to form Biliverdin. Biliverdin is then converted to Bilirubin by Biliverdin reductase. In physiological state, the highest activity of HMOX1 is found in the spleen, where senescent erythrocytes are sequestrated and destroyed. Heme Oxygenase-1 is involved in the regulation of cardiovascular function and its adaptive response to a variety of stressors. HMOX1 is induced in the colon of ulcerative colitis. HMOX1 is found to overexpress with a higher extent of intraplaque angiogenesis implies a multi-faceted role for HMOX1 in modulating the progression of atherosclerosis. HMOX1 expression reduced LPS-stimulated secretion of MCP-1, IL-6, IL-10, and TNF-alpha in murine and human macrophages.

Acireductone dioxygenase 1 (ADI1) is a part of the acireductone dioxygenase family of metal-binding enzymes, which are involved in methionine salvage. ADI1 regulates mRNA processing in the nucleus, and carries out different functions depending on its localization. Related pseudogenes have been defined on chromosomes 8 and 20. ADI1 down-regulates cell migration arbitrated by MMP14.

Inositol oxygenase is a non-heme di-iron enzyme which oxidizes myo-inositol to glucuronic acid. In addition, inositol oxygenase oxidizes the less abundant chiro isomer of inositol. MIOX enzyme is a component of the only known pathway for the catabolism of inositol in humans. MIOX is expressed mostly in the kidneys. Reduction of Inositol Oxygenase and accumulation of polyols, such as inositol and xylitol, have been implicated as contributing factors in complications linked with diabetes.