Background The mechanisms of sulfite intolerance are unknown. It has been suggested that, in some cases, it could be due to a partial sulfite-oxidase deficiency. In these patients, this enzyme is unable to metabolize adequately an overload of ingested or inhaled exogenous sulfite, triggering a bronchospasm. Cyanocobalamin is able to catalyze the extracellular oxidation of sulfites, preventing s...

Sulfite oxidase (EC 1.8.3.1), when reduced by sulfite, exhibited the electron paramagnetic resonance spectrum of molybdenum(V). Specific calorimetric analyses demonstrated that the purified enzyme contained 1 molybdenum per heme. The electron paramagnetic resonance signal of molybdenum, which was generated by the addition of sulfite, was enriched by the purification procedure to the same degree...

An enzyme electrode was developed using the enzyme sulfite oxidase (EC1.8.3.1) immobilized onto pig intestine. Hydrogen peroxide produced was monitored amperometrically. All experimental parameters such as pH, temperature, buffer constituent concentration, were thoroughly investigated and optimized when appropriate. The response to sulfite concentration was linear in the range 5.2´...

The market value of crustaceans depreciates during storage due to the appearance melanosis caused by polyphenol oxidases. Sulfite derivatives are used as melanosis-inhibiting agents, but their unhealthy effects make it preferable replace them with natural preservatives. In this work, a crude enzymatic extract from whiteleg shrimp (Penaeus vannamei) was characterized and test diphenol oxidase-in...

Several point mutations in the gene of human sulfite oxidase (hSO) result in isolated sulfite oxidase deficiency, an inherited metabolic disorder. Three conserved residues (H304, R309, K322) are hydrogen bonded to the phosphate group of the molybdenum cofactor, and the R309H and K322R mutations are responsible for isolated sulfite oxidase deficiency. The kinetic effects of the K322R mutation ha...

The aerobic oxidation of sulfite thus provides a magnified manometric response to the chain initiating event. Advantage was taken of this circumstance to develop an ultrasensitive assay for milk xanthine oxidase (5). The data obtained were consistent with the hypothesis that xanthine oxidase, when acting on purine substrates, initiates the aerobic oxidation of sulfite by the generation of free ...

A patient suffering from a combined deficiency of sulfite oxidase (sulfite dehydrogenase; sulfite:ferricytochrome c oxidoreductase, EC 1.8.2.1) and xanthine dehydrogenase (xanthine:NAD+ oxidoreductase, EC 1.2.1.37) is described. The patient displays severe neurological abnormalities, dislocated ocular lenses, and mental retardation. Urinary excretion of sulfite, thiosulfate, S-sulfocysteine, ta...

The aerobic oxidation of sulfite thus provides a magnified manometric response to the chain initiating event. Advantage was taken of this circumstance to develop an ultrasensitive assay for milk xanthine oxidase (5). The data obtained were consistent with the hypothesis that xanthine oxidase, when acting on purine substrates, initiates the aerobic oxidation of sulfite by the generation of free ...

In this research, an enzyme modified electrode has been produced during the electropolymerization of aniline through incorporation of sulfite oxidase into a conducting polymer. Then the bioelectrochemical response of resulted sulfite biosensor was investigated at different experimental conditions. Study of  the stability of the resulted sulfite biosensor revealed that formation of a passive...

? Multiple Choice Questions Section The Neurosciences Journal includes this section of multiple choice questions as part of its commitment to continuous education and learning in Neurosciences. Experts in various neuroscience specialties are invited to participate with their knowledge and expertise in this section. Neurology, neurosurgery, and other board residents are encouraged to read this s...