2.1.3.2 carbamoyl phosphate + L-aspartate - 2.1.3.2 carbamoyl phosphate + L-aspartate the enzyme catalyzes the first committed step in pyrimidine biosynthesis 2.1.3.2 carbamoyl phosphate + L-aspartate there is no preferential partitioning of carbamoyl phosphate between the arginine and pyrimidine biosynthetic pathways. Channeling must occur during the dynamic association of coupled enzymes pairs. The interaction of carbamoyl-phosphate synthetase/aspartate transcarbamoylase is demonstrated by the unexpectedly weak inhibition of the coupled reaction by the bisubstrate analog, N-(phosphonacetyl)-L-aspartate. In the coupled reaction, the effective concentration of carbamoyl phosphate in the vicinity of the aspartate transcarbamoylase active site is 96fold higher than the concentration in the bulk phase. Channeling probably plays an essential role in protecting this very unstable intermediate of metabolic pathways performing at extreme temperatures 2.1.3.2 carbamoyl phosphate + L-aspartate the enzyme catalyzes the first step in the pyrimidine biosynthetic pathway 2.1.3.2 carbamoylphosphate + L-aspartate - 2.1.3.2 carbamoylphosphate + L-aspartate catalyzes the formation of carbamoyl-L-aspartate, the first compound unique to the biosynthetic pathway for pyrimidine nucleotides 2.1.3.2 carbamoylphosphate + L-aspartate second enzyme of pyrimidine synthesis 2.1.3.2 L-aspartate + carbamoyl phosphate - 2.1.3.2 additional information link between enzyme activity and gametogenesis 2.1.3.2 additional information ACT-DHOD gene is transcribed to ACT-DHOD mRNA, translated to the single protein, ACT-DHOD, and finally converted to mature independent DHOD and ACT 2.1.3.2 additional information direct intermolecular interactions between the enzymes catalyzing the first three reaction steps of the de novo pyrimidine biosynthetic pathway, carbamoylphosphate synthetase II (CPSII), aspartate transcarbamoylase (ATC), and dihydroorotase (DHO), of the parasitic protist Trypanosoma cruzi, interaction analysis, overview 2.1.3.2 additional information CAD is a rate-limiting enzyme required for the formation of UDP sugar, upstream of two different metabolic pathways; the de novo biosynthesis of pyrimidine and pyrimide-based nucleotides, and the formation of UDP sugar intermediates, required for UDP-dependent glycosylation events