The Activation of Ox‐Brain NAD+‐Dependent Isocitrate Dehydrogenase by Magnesium Ions
- 1 January 1981
- journal article
- research article
- Published by Wiley in European Journal of Biochemistry
- Vol. 113 (3) , 477-483
- https://doi.org/10.1111/j.1432-1033.1981.tb05088.x
Abstract
Two independent methods were used to assess the dependence of the activity of ox brain NAD+-dependent isocitrate dehydrogenase on the concentration of Mg2+. The results indicated the complex between Mg and isocitrate to be the true substrate for the enzyme. Free isocitrate is neither a substrate nor an inhibitor of the enzyme, but free Mg2+ inhibit competitively with respect to the Mg-isocitrate complex. The inhibition of the enzyme by ATP and citrate appears to be largely explicable in terms of their effects on the concentration of the complex between Mg2+ and isocitrate. The dependence of the activation of the enzyme by ADP on the concentration of Mg2+ suggests that free ADP, rather than its complex with Mg2+, is the activator.This publication has 12 references indexed in Scilit:
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