The activation of ox-brain NAD+-dependent isocitrate dehydrogenase by magnesium ions.
Eur J Biochem
; 113(3): 477-83, 1981 Jan.
Article
em En
| MEDLINE
| ID: mdl-7215339
ABSTRACT
Two independent methods were used to assess the dependence of the activity of ox brain NAD+-dependent isocitrate dehydrogenase on the concentration of magnesium ions. The results indicated the complex between magnesium and isocitrate to be the true substrate for the enzyme. Free isocitrate is neither a substrate nor an inhibitor of the enzyme but free magnesium ions inhibit competitively with respect to the magnesium-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 magnesium ions suggests that free ADP, rather than its complex with Mg2+, is the activator.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Encéfalo
/
Isocitrato Desidrogenase
/
Magnésio
Limite:
Animals
Idioma:
En
Revista:
Eur J Biochem
Ano de publicação:
1981
Tipo de documento:
Article