Vanadate inhibits liver fructose-2,6-bisphosphatase.
Vanadate was found to be a reversible non-competitive inhibitor of chicken liver fructose-2,6-bisphosphatase. The inhibition was best observed in the presence of glycerol 2- or 3-phosphate and half-maximal effect was obtained with about 0.15 mM vanadate. Vanadate decreased the extent of phosphorylation of the enzyme (E-P) by fructose 2,6-[2-32P]bisphosphate. This did not result from an increased rate of E-P breakdown, as is the case with phosphoglycerate mutase, an enzyme which shares structural and functional similarity to fructose-2,6-bisphosphate. The data were consistent with the formation of a dead-end transition state analogue of phosphate in the active site. Inhibition of fructose-2,6-bisphosphatase by vanadate offers a likely explanation for the increase in fructose 2,6-bisphosphate concentration brought about by vanadate in isolated rat hepatocytes.
Rider
M H
MH
Hormone and Metabolic Research Unit, International Institute of Cellular and Molecular Pathology, Brussels, Belgium.
Bartrons
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R
Hue
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L
D000818:Animals; D002645:Chickens; D004305:Dose-Response Relationship, Drug; D005635:Fructosediphosphates / Q000378:metabolism*; D005994:Glycerophosphates / Q000494:pharmacology; D006019:Glycolysis / Q000187:drug effects; D006598:Hexosediphosphates / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D025481:Phosphofructokinase-2; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors*; D010766:Phosphorylation; D014638:Vanadates / Q000494:pharmacology*
D005635:Fructosediphosphates; D005994:Glycerophosphates; D006598:Hexosediphosphates; D014638:Vanadates; C027652:fructose 2,6-diphosphate; D025481:Phosphofructokinase-2; D010744:Phosphoric Monoester Hydrolases