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
May 1, 1975·Proceedings of the National Academy of Sciences of the United States of America·R J KentP P Cohen
Dec 1, 1978·International Journal for Parasitology·M KobayashiM Tatibana
Jun 17, 1975·Biochemistry·M MoriM 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
Jan 1, 1972·Advances in Enzyme Regulation·M Tatibana, K Shigesada
Sep 1, 1972·Journal of Biochemistry·M Tatibana, K Shigesada
Dec 15, 1972·Comparative Biochemistry and Physiology. B, Comparative Biochemistry·B Kurelec
Sep 1, 1972·Journal of Biochemistry·M Tatibana, K Shigesada
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 23, 1966·Science·A Piérard
Oct 1, 1966·Biochemistry·P M Anderson, A Meister
Dec 1, 1969·Analytical Biochemistry·L M Prescott, M E Jones
Jan 23, 1967·Biochemical and Biophysical Research Communications·M Tatibana, K Ito
Apr 1, 1963·The Biochemical Journal·L STEVENS, L A STOCKEN
Mar 1, 1962·Analytical Biochemistry·F ROTHMAN, A HIGA
Citations
Jan 1, 1987·Comparative Biochemistry and Physiology. B, Comparative Biochemistry·T Aoki, H Oya
Jan 1, 1987·Comparative Biochemistry and Physiology. B, Comparative Biochemistry·T Aoki, H Oya
Sep 28, 1998·Biochimica Et Biophysica Acta·T NaraT Aoki