Chemiluminescent Assays in the Study of Purine Metabolism
The discovery that in cells from patients with hypoxanthine guanine phosphoribosyltransferase (HGPRT) deficiency purine overproduction is associated with an elevated intracellular concentration of phosphoribosylpyro-phosphate (PRPP) (1) has led to a reevaluation of the importance of this compound in the regulation of purine biosynthesis de novo. The work which flowed from this discovery led to the identification of an inherited super-activity of PRPP synthetase in over a dozen families in which affected individuals showed gout and/or uric acid overproduction (2). However to date HGPRT deficiency and increased activity of PRPP synthetase are the only two well documented enzyme defects of purine synthesis and reutilization identified among hyperuricemic patients. These genetic aberrations account for less 10% of all hyperuricemic patients who overproduce uric acid.
KeywordsUric Acid Purine Base Purine Synthesis Purine Biosynthesis Hypoxanthine Guanine Phosphoribosyltransferase
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