Sulfur dioxygenase

The possible roles in sulfur (and sulfide or sulfane-) oxidation of a sulfur dioxygenase or of electron-transport-linked hydration/dehydrogenation are outlined above, but the fate of the sulfite product may be more complex than previously considered. Vishniac and Santer (1957) showed that S-labeled sulfide was rapidly oxidized first to thiosulfate (and polythionates) and then to sulfate by T. thioparus. This observation was incorporated into the original Peck scheme (Eqs. 15.13-15.17) by Peck and Fisher (1962), who realized that the complete oxidation of thiosulfate (after reductive scission to sulfite and sulfide Eq. 15.3) could be explained if there was recycling of sulfide to produce thiosulfate ... 

RUBREDOXIN.NAD REDUCTASE SUCCINATE DEHYDROGENASE SULFITE REDUCTASE SULFUR DIOXYGENASE THYMIDINE 2 -HYDROXYLASE XANTHINE OXIDASE Iron(ll) hydroxide (Fe(OH)2),... 

SULFUR DIOXYGENASE Sulfuric add, autoprotolysis constant, AUTOPROTOLYSIS Superoxide,... 

An iron sulfur-flavoprotein that transfers electrons directly to the dioxygenase, as in phthalate dioxygenase (class I)... 

Component B is a monomeric reductase with a molecular weight of 35,000 and contains per mol of enzyme, 1 mol of FMN, 2.1 mol of Fe, and 1.7 mol of labile sulfur. After reduction with NADH, the ESR spectrum showed signals that were attributed to a [2Fe-2S] structure and a flavo-semiquinone radical (Schweizer et al. 1987). The molecular and kinetic properties of the enzyme are broadly similar to the Class IB reductases of benzoate 1,2-dioxygenase and 4-methoxybenzoate monooxygenase-O-demethylase. 

I, 2-diol and NAD. This multiprotein complex contains an iron-sulfur flavoprotein, an iron-sulfur oxygenase, and ferredoxin. See also Phthalate Dioxygenase... 

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. 

R)-2-METHYLMALATE DEHYDRATASE NICOTINATE DEHYDROGENASE NITRATE REDUCTASE NITRITE REDUCTASE PHENYLALANINE MONOOXYGENASE PROLYL 3-HYDROXYLASE PROLYL 4-HYDROXYLASE PROTOCATECHUATE 3,4-DIOXYGENASE PROTOCATECHUATE 4,5-DIOXYGENASE RIESKE IRON-SULFUR PROTEIN RUBREDOXIN... 

It should be noted that non-heme oxygenases can also degrade aromatics such as biphenyls and naphthalene (Scheme 7.23). A naphthalene dioxygenase consists of a catalytic oxygenase component with a mononuclear iron site, an iron-sulfur flavoprotein reductase and an iron-sulfur ferredoxin transferring electrons from... 

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