PMID: 6108508Mar 1, 1980Paper

Control of pyrimidine biosynthesis in the Ascaris ovary: regulatory properties of glutamine-dependent carbamoyl-phosphate synthetase and copurification of the enzyme with aspartate carbamoyltransferase and dihydroorotase

Molecular and Biochemical Parasitology
T AokiM Tatibana

Abstract

Glutamine-dependent carbamoyl-phosphate synthetase, the first enzyme of the de novo biosynthetic pathway for pyrimidine nucleotides, was purified about twenty-fold from 105 000 x g supernatant of the Ascaris ovary homogenate. The enzyme activity was feedback-inhibited by UDP and UTP while it was stimulated by 5-phosphoribosyl 1-pyrophosphate. Most of the catalytic and regulatory properties of the Ascaris synthetase were similar to those of the mammalian synthetase. A significant difference is that the Ascaris enzyme was more strongly inhibited by UDP than by UTP whereas the mammalian enzyme is more sensitive to UTP than to UDP. The Ascaris enzyme was also inhibited by other various nucleoside diphosphates, such as dUDP, dADP and CDP, generally more strongly than by the corresponding nucleoside triphosphates. Aspartate carbamoyltransferase and dihydroorotase, the second and third enzymes of the pathway, were also demonstrated in the supernatant fraction. These two enzymes were copurified with the synthetase and the relative activities of the three enzymes remained nearly constant (1:850-890:50-60) throughout the purification. In a sucrose gradient centrifugation, the enzymes cosedimented as a single peak with a sedimentation coe...Continue Reading

References

Jul 3, 1978·European Journal of Biochemistry·B P Jarry
Jan 1, 1979·Comparative Biochemistry and Physiology. B, Comparative Biochemistry·T Aoki, H Oya
Dec 1, 1978·International Journal for Parasitology·M KobayashiM Tatibana
Oct 15, 1973·Biochemical and Biophysical Research Communications·M Mori, M Tatibana
Jan 31, 1972·Biochemical and Biophysical Research Communications·M Tatibana, K Shigesada
Dec 15, 1972·Comparative Biochemistry and Physiology. B, Comparative Biochemistry·B Kurelec
Aug 20, 1971·Biochemical and Biophysical Research Communications·N J HoogenraadN Kretchmer
Nov 5, 1971·Biochemical and Biophysical Research Communications·W T Shoaf, M E Jones
Dec 1, 1969·Analytical Biochemistry·L M Prescott, M E Jones
Jan 23, 1967·Biochemical and Biophysical Research Communications·M Tatibana, K Ito
Mar 1, 1962·Analytical Biochemistry·F ROTHMAN, A HIGA

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Citations

Jan 1, 1987·Comparative Biochemistry and Physiology. B, Comparative Biochemistry·T Aoki, H Oya
Sep 28, 1998·Biochimica Et Biophysica Acta·T NaraT Aoki

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