Catechol-2,3-oxygenase

Shoda M, S Udaka (1980) Preferential utilizatiion of phenol rather than glucose by Trichosporon cutaneum possessing a partiality constitutive catechol 1,2-oxygenase. Appl Environ Microbiol 39 1129-1133. 

For the determination of phenols and amines enzymes with low selectivity, e.g. laccase, horseradish peroxidase, tyrosinase, and polyphenol oxidase, as well as specific enzymes, e.g. phenol hydroxylase and catechol-1,2-oxygenase, can be used in biosensors. 

The flavoprotein phenol-2-hydroxylase (EC 1.14.13.7) and the o-phenol-splitting catechol-1,2-oxygenase (EC 1.13.1.1) are prepared from... 

Specific catechol determination is demanded in the photographic, paint, and pharmaceutical industries. Neujahr (1980) combined immobilized catechol-1,2-oxygenase with an oxygen electrode and employed the sensor for catechol measurement. The sensor was selective for catechol and 3- and 4-methylcatechol. Phenol, resorcinol, cresol, vanil-line, and dihydroxyphenylalanine (DOPA) did not interfere. 

DE HAAN H. 1976. Evidence for the induction of catechol-1,2-oxygenase by fulvic acid. Plant and Soil, 4, 129-136. 

Classical tyrosinase (catechol oxygenase, EC 1.10.3.1) catalyses the first step in the synthesis of Melanin (see) from tyrosine. 

There is an additional problem that has important implications for the bioremediation of contaminated sites when two substrates such as a chlorinated and an alkylated aromatic compound are present. The extradiol fission pathway is generally preferred for the degradation of alkylbenzenes (Figure 9.17), although this may be incompatible with the degradation of chlorinated aromatic compounds since the 3-chlorocatechol produced inhibits the activity of the catechol-2,3-oxygenase (Klecka and Gibson 1981 Bartels et al. 1984). 

Zeyer J, HP Kocher (1988) Purification and characterization of a bacterial nitrophenol oxygenase which converts orf/io-nitrophenol to catechol and nitrite. J Bacteriol 170 1789-1794. 

The first step is catalysed by the tetrahydrobiopterin-dependent enzyme tyrosine hydroxylase (tyrosine 3-monooxygenase), which is regulated by end-product feedback is the rate controlling step in this pathway. A second hydroxylation reaction, that of dopamine to noradrenaline (norepinephrine) (dopamine [3 oxygenase) requires ascorbate (vitamin C). The final reaction is the conversion of noradrenaline (norepinephrine) to adrenaline (epinephrine). This is a methylation step catalysed by phenylethanolamine-jV-methyl transferase (PNMT) in which S-adenosylmethionine (SAM) acts as the methyl group donor. Contrast this with catechol-O-methyl transferase (COMT) which takes part in catecholamine degradation (Section 4.6). 

Horvath, R.S. Co-metabolism of methyl- and chloro-substituted catechols by an Achromobactersp. possessing a new mete-cleavage oxygenase, Blochem. J., 119 871-876, 1970a. 

Benzoate 1,2-dioxygenase [EC 1.14.12.10], also called benzoate hydroxylase, catalyzes the reaction of benzoate with dioxygen and NADH to generate catechol, carbon dioxide, and NAD+. This is a multiprotein system which contains a reductase which is an iron-sulfur flavoprotein (FAD) and an iron-sulfur oxygenase. 

The formation of the monodehydroascorbate free radical by dopamine P-mono-oxygenase was similarly demonstrated by the acceleration of the reduction of Fe(III)-cytochrome c and by direct spectrophotometry at 360 nm The action of the laccase from the mushroom Agaricus hisporum on catechol yielded also the semiquinone as the result of a one-electron transfer... 

You are concerned about the fate of 2-nitrophenol (NP) found at a concentration of about 10 ppb (0.07 /iM) in some groundwater. According to the literature (Zeyer and Kocher, 1988), this compound can be degraded aerobically by soil bacteria. The biodegradation pathway begins with an oxygenase that converts NP to catechol ... 

Both of the oxygen atoms incorporated into catechol have been shown639 by labeling studies to be derived from molecular oxygen. Pyrocatechase and other related oxygenases are known to require either copper or iron for maximum activity. An efficient, nonenzymatic oxidation of catechol to s,os-muconate with molecular oxygen activated by cuprous chloride has been recently presented as a model reaction for pyrocatechase.649... 

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