Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.4.1.4 (glutamate dehydrogenase)
 4,358 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Four cytoplasmically synthesized rat liver mitochondrial enzymes, located either as soluble enzymes in the mitochondrial matrix (L-glutamate dehydrogenase and malate dehydrogenase or in the intermembrane space (sulfite oxidase) or as an integral membrane protein located on the matrix face of the inner mitochondrial membrane (D-beta-hydroxybutyrate dehydrogenase), were all shown to be synthesized as precursors larger than their mature counterparts by 1000-6000 daltons. These larger forms were detected in vitro, in a cell-free protein synthesizing system programmed with either total rat liver RNA or with RNA isolated from free polysomes or with free polysomes, and in vivo, in the two cases that were investigated (L-glutamate dehydrogenase and D-beta-hydroxybutyrate dehydrogenase), by pulse labeling of Buffalo rat liver cells in culture. The intracellular site of synthesis of all four mitochondrial enzymes was shown to be primarily on free polysomes and not on membrane-bound polysomes.
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PMID:Rat liver L-glutamate dehydrogenase, malate dehydrogenase, D-beta-hydroxybutyrate dehydrogenase, and sulfite oxidase are each synthesized as larger precursors by cytoplasmic free polysomes. 706 82

Patients affected by sulfite oxidase (SO) deficiency present severe seizures early in infancy and progressive neurological damage, as well as tissue accumulation of sulfite, thiosulfate and S-sulfocysteine. Since the pathomechanisms involved in the neuropathology of SO deficiency are still poorly established, we evaluated the effects of sulfite on redox homeostasis and bioenergetics in cerebral cortex, striatum, cerebellum and hippocampus of rats with chemically induced SO deficiency. The deficiency was induced in 21-day-old rats by adding 200ppm of tungsten, a molybdenum competitor, in their drinking water for 9weeks. Sulfite (70mg/kg/day) was also administered through the drinking water from the third week of tungsten supplementation until the end of the treatment. Sulfite decreased reduced glutathione concentrations and the activities of glutathione reductase and glutathione S-transferase (GST) in cerebral cortex and of GST in cerebellum of SO-deficient rats. Moreover, sulfite increased the activities of complexes II and II-III in striatum and of complex II in hippocampus, but reduced the activity of complex IV in striatum of SO-deficient rats. Sulfite also decreased the mitochondrial membrane potential in cerebral cortex and striatum, whereas it had no effect on mitochondrial mass in any encephalic tissue evaluated. Finally, sulfite inhibited the activities of malate and glutamate dehydrogenase in cerebral cortex of SO-deficient rats. Taken together, our findings indicate that cerebral cortex and striatum are more vulnerable to sulfite-induced toxicity than cerebellum and hippocampus. It is presumed that these pathomechanisms may contribute to the pathophysiology of neurological damage found in patients affected by SO deficiency.
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PMID:Higher susceptibility of cerebral cortex and striatum to sulfite neurotoxicity in sulfite oxidase-deficient rats. 2752 30