Oxygenases oxidase

As mentioned above, redox enzymes (oxidoreductases) are divided into four large groups dehydrogenases, oxygenases, oxidases, and peroxidases and catalases. 

Volume XII Oxidation-Reduction, Part B Electron Transfer (II), Oxygenases, Oxidases (I)... 

Oxidases couple the oxidation of an organic substrate to the two- or four-electron reduction of O2, producing H2O2 or two molecules of H2O, respectively. Oxygen atoms from dioxygen are not incorporated into the product, unlike reactions catalyzed by oxygenases. Oxidase reactions may proceed via iimer-sphere or outer-sphere mechanisms. 

Boyer, P. D. (ed.) The Enzymes, Vol. 12, Oxygenation - Reduction, Part B, Electron Transfer, Oxygenases, Oxidases. Academic Press, New York 1976 Hemmerich, P. The present status of flavin and flavocoenzyme chemistry. Prog. Chem. Org. Nat. Prod. 33, 451-517 (1976)... 

Other experiments with Gibberellafujikuroi the fungus that produces gibbereUin, indicate that GA production is blocked by BAS 111. Very detailed and carehil experiments conducted with enzymes in ceU-free systems strongly support this mode of action, ie, using /-kaurene oxidase and cinnamate 4-mono-oxygenase isolated from pea apices and soybean suspension cells, and avanone-2-hydtoxylase and dibydroxypterocarpane 6-hydtoxylase from soybean suspension cells (31). 

Cytochrome P450 (CYP) Cytochrome P450 isozymes Cytochrome P450 mono-oxygenases Mixed function oxidases... 

Cytochrome P450 (CYP) mono-oxygenases, also called mixed function oxidases, are versatile hemoprotein enzymes that catalyze the cleavage of molecular oxygen to incoiporate one oxygen atom into a substrate molecule and one atom into water [1]. The general stoichiometry of the reaction is as follows (S-H, substrate) ... 

Oxidoreductases have a variety of functions in metabolism oxidases and dehydrogenases play major roles in respiration hydroperoxidases protect the body against damage by free radicals and oxygenases mediate the hydroxylation of drugs and steroids. 

These include the mitochondrial respiratory chain, key enzymes in fatty acid and amino acid oxidation, and the citric acid cycle. Reoxidation of the reduced flavin in oxygenases and mixed-function oxidases proceeds by way of formation of the flavin radical and flavin hydroperoxide, with the intermediate generation of superoxide and perhydroxyl radicals and hydrogen peroxide. Because of this, flavin oxidases make a significant contribution to the total oxidant stress of the body. 

Solomon El, Sundaram UM, Machonkin TE. 1996. Multicopper oxidases and oxygenases. Chem Rev 96 2563-2605. 

Oxidoreductases dehydrogenase, oxidase oxygenase, peroxidase oxidation or reduction... 

Dopamine mono-oxygenase Coproporphyrin decarboxylase Ethylene receptor Methane oxidase Terminal glycine oxidases CP-x type ATP-ase ATx-1 (Lys 7)... 

Later, it was discovered138 that the FAD coenzymes of certain oxidases display large changes in their fluorescence if exposed to their substrates. Thus, the fluorescence of the FAD unit of lactate mono-oxygenase changes substantially on loading with lactate, and this can serve as the analytical information in an optical sensor. 

We focus here on the use of oxygenases, particularly the blue copper oxygenases, such as laccase and bilirubin oxidase, which can biocatalytically reduce oxygen directly to water at relatively high reduction potentials under mild conditions. First, however, we will briefly consider reports on the use of hydrogen peroxide as an oxidant in biocatalytic fuel cells. 

A broad spectrum of chemical reactions can be catalyzed by enzymes Hydrolysis, esterification, isomerization, addition and elimination, alkylation and dealkylation, halogenation and dehalogenation, and oxidation and reduction. The last reactions are catalyzed by redox enzymes, which are classified as oxidoreductases and divided into four categories according to the oxidant they utilize and the reactions they catalyze 1) dehydrogenases (reductases), 2) oxidases, 3) oxygenases (mono- and dioxygenases), and 4) peroxidases. The latter enzymes have received extensive attention in the last years as bio catalysts for synthetic applications. Peroxidases catalyze the oxidation of aromatic compounds, oxidation of heteroatom compounds, epoxidation, and the enantio-selective reduction of racemic hydroperoxides. In this article, a short overview... 

A major class of enzymes that catalyze oxidation-reduction reactions. This class includes dehydrogenases, reductases, oxygenases, peroxidases, and a few synthases. Examples include alcohol dehydrogenase (EC 1.1.1.1), aldehyde oxidase (EC 1.2.3.1), orotate reductase (EC 1.3.1.14), glutamate synthase (EC 1.4.1.14), NAD(P) transhydrogenase (EC 1.6.1.1), and glutathione peroxidase (EC 1.11.1.9). 

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