Regulation of rat-kidney cortex fructose-1,6-bisphosphatase activity. II. Effects of adenine nucleotides.
1. The native rat-kidney cortex Fructose-1,6-bisphosphatase is differentially regulated by adenine nucleotides in the presence of divalent cations. 2. Binding of AMP and ADP to the enzyme is co-operative. The inhibition by both nucleotides show an uncompetitive mechanism AMP being the most efficient inhibitor. 3. Mg2+ decreases the inhibition produced by AMP and ADP by enhancing their I0.5 and completely annulates the inhibitory effect of ATP. 4. In the presence of Mn2+ ADP behaves as an inhibitor but no inhibition is evident with AMP, suggesting the existence of different allosteric sites for each nucleotide.
Sola
M M
MM
Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Granada, Spain.
Oliver
F J
FJ
Salto
R
R
Gutiérrez
M
M
Vargas
A M
AM
D000227:Adenine Nucleotides / Q000494:pharmacology*; D000244:Adenosine Diphosphate / Q000494:pharmacology; D000249:Adenosine Monophosphate / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D006597:Fructose-Bisphosphatase / Q000037:antagonists & inhibitors / Q000187:drug effects*; D007672:Kidney Cortex / Q000187:drug effects* / Q000201:enzymology; D008274:Magnesium / Q000494:pharmacology*; D008345:Manganese / Q000494:pharmacology*; D051381:Rats
D000227:Adenine Nucleotides; D000249:Adenosine Monophosphate; D008345:Manganese; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D006597:Fructose-Bisphosphatase; D008274:Magnesium