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Published on: August 17, 2019
Inhibition of aspartate transcarbamylase by a phenobarbital derivative
M Balbaa1, G Yacout, T Ghonaim
1Department of Biochemistry, Faculty of Science, Alexandria University, Alexandria, Egypt. mahmoudbalbaa@usa.net
Abstract:
Mammalian and hepatic aspartate transcarbamylase is inhibited by phenobarbital p-nitrophenylhydrazone in a reversible and non-competitive type with Ki values 8.45 x 10(-5) and 9.64 x 10(-5) M in the reactions toward carbamyl phosphate and aspartate, respectively. In vivo inhibition occurred in a dose-dependent manner in which less than 50% of the activity was retained. These observations suggest that this inhibitor may interfere with the in vivo regulation of this enzyme and lead to an additional biological effect of phenobarbitals.
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