Cooperative effects of CTP on calf liver CTP synthetase.
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چکیده
منابع مشابه
Cooperative effects of CTP on calf liver CTP synthetase.
In all previous kinetics studies of calf liver CTP synthetase, simple Michaelis-Menten hyperbolic plots were obtained. In this study it was shown that calf liver CTP synthetase could generate sigmoidal kinetic plots as a function of the substrate UTP when in the presence of the product of the reaction, CTP. The Hill number was estimated to be 2.8. The enzyme did not generate sigmoidal plots as ...
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The nucleotide-dependent tetramerization of purified native URA7-encoded CTP synthetase (EC 6.3.4.2, UTP: ammonia ligase (ADP-forming)) from the yeast Saccharomyces cerevisiae was characterized. CTP synthetase existed as a dimer in the absence of ATP and UTP. In the presence of saturating concentrations of ATP and UTP, the CTP synthetase protein existed as a tetramer. Increasing concentrations ...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1979
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(19)86499-2