Abnormal circulating enzyme concentration or activity Abnormal phosphoribosylpyrophosphate synthetase level 2019-03-09T17:34:47Z Intracellular availability of the sugar phosphate, 5-phosphoribosyl 1-pyrophosphate (PP-ribose-P), is an important factor in regulation of the rate of purine synthesis de novo. PP-ribose- P synthetase (EC2.7.6.1) is an enzyme that catalyzes the synthesis of PP-ribose-P from ATP and ribose-5-phosphate. An increased activity of PP-ribose- P synthetase can be associated with increased PP-ribose-P concentrations and increased purine biosynthetic rates. Increased purine production in turn can be associated with gout. Any deviation from the normal level of the enzyme phosphoribosyl pyrophosphatesynthetase, which catalyzes the synthesis of PP-ribose-P from ATP and ribose-5-phosphate.