Reaction
ATCase is a highly regulated enzyme that catalyses the first committed step in pyrimidine biosynthesis, the condensation of aspartate and carbamyl phosphate to form N-carbamyl-L-aspartate and inorganic phosphate. ATCase controls the rate of pyrimidine biosynthesis by altering its catalytic velocity in response to cellular levels of both pyrimidines and purines. The end-product of the pyrimidine pathway, CTP, induces a decrease in catalytic velocity, whereas ATP, the end-product of the parallel purine pathway, exerts the opposite effect, stimulating the catalytic activity.
Read more about this topic: Aspartate Carbamoyltransferase
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