Kinetic studies with skeletal-muscle hexokinase.
نویسنده
چکیده
Rat skeletal-muscle hexokinase was partially purified by ammonium sulphate fractionation and gel filtration. The mechanism of the skeletal-muscle hexokinase was studied kinetically by initial-velocity analysis and product inhibition. Glucose 6-phosphate was a non-competitive inhibitor of glucose and ATP. ADP was a non-competitive inhibitor of glucose and a competitive inhibitor of ATP. The data on product inhibition and initial-velocity analysis of skeletal-muscle hexokinase support an ordered sequential mechanism (ordered Bi Bi) where the addition of substrates and release of products is in the order: ATP, glucose, glucose 6-phosphate and ADP.
منابع مشابه
Kinetics, mechanism, and regulation of rat skeletal muscle hexokinase.
Initial rate studies were employed to investigate the kinetic mechanism of action of rat skeletal muscle type II hexokinase (EC 3.7.1.1). These investigations involved the use of substrate analogs which act as competitive inhibitors and product inhibition experiments. The findings indicate that substrates n-glucose and MgATP2add randomly to hexokmase. Both products exhibit noncompetitive inhibi...
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The kinetic mechanism of rat skeletal muscle hexokinase (hexokinase II) was investigated in light of a proposal by Cornish-Bowden and his co-workers (Gregoriou, M., Trayer, I. P., and Cornish-Bowden, A. (1983) Eur. J. Biochem. 134, 283-288). These investigators reported that the kinetic mechanism is ordered, with glucose adding before ATP and ADP dissociating from hexokinase before glucose-6-P....
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عنوان ژورنال:
- The Biochemical journal
دوره 100 3 شماره
صفحات -
تاریخ انتشار 1966