Hydroxy dioxygenase

Rhizobia. Taxa belonging to both the genera Rhizobium and Bradyrhizobium are capable of degrading simple aromatic compounds including benzoate (Chen et al. 1984) and 4-hydroxy-benzoate (Parke and Omston 1986 Parke et al. 1991). It has been shown that 4-hydroxyben-zoate hydroxylase is required for the transport of 4-hydroxybenzoate into the cell (Wong et al. 1994). In strains of Rhizobium trifolium, the metabolism of benzoate involves either 3,4-dihydroxybenzoate (protocatechuate) 3,4-dioxygenase (Chen et al. 1984), or catechol... 

It is clear from the preceding comments that there is no absolute distinction between the oxygenase activities mediated by dioxygenases. This is even less clear for heteroarenes than it is for carbocyclic compounds. An illustrative example is provided by Pseudomonas putida strain 86 in which 8-hydroxy-quinol-2-one is produced from quinol-2-one (Rosche et al. 1997). 

Denoya CD, DD Skinner, MR Morgenstern (1994) A Streptomyces avermitilis gene encoding a 4-hydroxy-phenylpyruvic acid dioxygenase-like protein that directs the production of homogentisic acid and an ochronotic pigment in Escherichia coli. J Bacterial 176 5312-5319. 

Iwabuchi T, S Harayama (1998b) Biochemical and molecular characterization of l-hydroxy-2-naphthoate dioxygenase from Nocardioides sp. KP7. J. Biol. Chem. 273 8332-8336. 

Bauer, I. Max, N. Fetzner, S., et al., Purification and Some Properties of lh-3-Hydroxy-4-Oxoquinaldine 2, 4-Dioxygenase From Arthrobacter Sp. R 61a and Comparison With lh-3-Hydroxy-4-Oxoquinoline 2, 4-Dioxygenase From Pseudomonas Putida 33/1. Eur. J. Biochem, 1996. 240 pp. 576-583. 

Fischer, F., and Fetzner, S., Site-Directed Mutagenesis of Potential Catalytic Residues in lh-3-Hydroxy-4-Oxoquinoline 2, 4-Dioxygenase, and Hypothesis on the Catalytic Mechanism of 2, 4-Dioxygenolytic Ring Cleavage. FEMS Microbiol Lett, 2000. 190 pp. 21-27. 

Biological. Soil bacteria readily decomposed o-phenylphenol but the products were not identified. By analogy to the degradation of phenol to catechol, o-phenylphenol may be converted to 3-phenylcatechol before degrading to biphenyl. Another pathway may be oxidation by a dioxygenase producing 2-hydroxy-2, 3 -dihydroxybiphenyl (Zbozinek, 1984)... 

This enzyme [EC 1.14.11.1], also known as y-butyrobe-taine, 2-ketoglutarate dioxygenase, catalyzes the reaction of 4-trimethylammoniobutanoate with S-keto-glutarate (or, 2-oxoglutarate) and dioxygen to yield 3-hydroxy-4-trimethylammoniobutanoate, succinate, and carbon dioxide. Both iron ions and ascorbate are needed as cofactors. 

This enzyme [EC 1.13.11.39], also referred to as bi-phenyl-2,3-diol 1,2-dioxygenase, catalyzes the reaction of biphenyl-2,3-diol with dioxygen to produce 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate and water. The enzyme can also use 3-isopropylcatechol as a substrate, forming 7-methyl-2-hydroxy-6-oxoocta-2,4-dienoate as a product. This protein is not identical with catechol 2,3-dioxygenase. 

This FAD-dependent enzyme [EC 1.14.12.4], also known as 3-hydroxy-2-methylpyridinecarboxylate dioxygenase, catalyzes the reaction of 3-hydroxy-2-methylpyridine-5-carboxylate with NAD(P)H and dioxygen to produce 2-(acetamidomethylene)succinate and NAD(P)+. 

Hawkinsinuria (autosomal dominant) 4-Hydroxy phenylpyruvic acid dioxygenase... 

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