Sulfite genetic deficiency

The first hint of an essential role of molybdenum in metabolism came from the discovery that animals raised on a diet deficient in molybdenum had decreased liver xanthine oxidase activity. There is no evidence that xanthine oxidase is essential for all life, but a human genetic deficiency of sulfite oxidase or of its molybdopterin coenzyme can be lethal.646,646a,b The conversion of molybdate into the molybdopterin cofactor in E. coli depends upon at least five genes.677 In Drosophila the addition of the cyanolyzable sulfur (Eq. 16-64) is the final step in formation of xanthine dehydrogenase.678 It is of interest that sulfur (S°) can be transferred from rhodanese (see Eq. 24-45), or from a related mercaptopyruvate sulfurtransferase679 into the desulfo form of xanthine oxidase to generate an active enzyme.680... 

Genetic deficiency of sulfite oxidase in humans develops in early infancy, with lethal outcome at the age of 2-3 years. The condition is associated with high urinary output of sulfite, thiosulfate and S-sulfo-L-cysteine, along with a marked decrease in urinary sulfate. The diseased... 

The essentiality of molybdenum for humans was determined after identification of sulfite oxidase as a molybdenum enzyme [10], the detection of a genetic deficiency of the molybdenum cofactor in a child [11,12], and the occurrence of molybdenum deficiency symptoms after molybdenum-free parenteral nutrition [13]. Apart from the genetic deficiency and the molybdenum-free parenteral nutrition, however, molybdenum deficiency does not occur in animals and humans since the general availability of molybdenum meets the requirements of animals and humans [14]. 

The enzymes are widely distributed in microorganisms, plants, and animals. " Three Mo-MPT enzymes have been found in mammals (1) xanthine dehydrogenase see Dehydrogenase) has many, varied roles in purine catabolism, drug metabolism, and oxidative stress response, (2) aldehyde oxidase is important in drug metabolism and the synthesis of retinoic acid from retinal, and (3) sulfite oxidase plays a cmcial role in the detoxification of sulfite produced in the degradation of cysteine and methionine. Genetic Mo-MPT deficiency in... 

Biochemistry of Zinc and Copper Zinc in the -Cells of the Pancreas Absorption of Zinc and Copper Plasma Zinc and Copper Levels Metallothionein and Ceruloplasmin Zinc Excretion and Zinc Deficiency Copper Excretion and Copper Deficiency Genetic Diseases of Copper Metabolism Molybdenum, Sulfite, and Sulfate Molybdenum Molybdenum Biochemistry Sulfite Sulfate... 

Organic sulfur metabolites are catabolized up to sulfate, which in turn is excreted via the urine. The final step of the pathway -the reduction of sulfite to sulfate - is dependent on the molybdenum-containing enzyme, sulfite oxidase. Both, a genetic disorder of sulfite oxidase synthesis or a molybdenum deficiency will reduce the urinary excretion of sulfate, but increase that of sulfite, S-sulfocysteine and thiosulfate. Due to the toxic effect of sulfite on the nervous system, this disease is characterized by mental retardation and dislocation of ocular lenses (Rajagopalan 1988). A marginal amount of molybdenum or sulfite oxidase worsen the sulfite detoxification of the... 

The deficiencies of cystathionine )5-synthase (CBS), sulfite oxidase, and methylenetetrahydrofolate reductase (MTHFR) may all result in central nervous system dysfunction, in particular mental retardation [1-3]. Defects of CBS and sulfite oxidase both cause dislocated lenses of the eyes, but the phenotypes are different otherwise. The manifestations of CBS deficiency, the most common of these disorders, and MTHFR deficiency range from severely affected to asymptomatic patients both may cause vascular occlusion. Deficiency of sulfite oxidase is clinically uniform, but genetically heterogeneous, and functional deficiency of the enzyme can result from several inherited defects of molybdenum cofactor biosynthesis [2, 4]. Hereditary folate malabsorption and defects of cobalamin transport (transcobala-min II deficiency) or cobalamin cofactor biosynthesis (cblC-G diseases) may cause megaloblastic anemia, in addition to CNS dysfunction [3, 5, 6]. 

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