Fructose 2-phosphate, an intermediate of the dephosphorylation of fructose 2,6-bisphosphate with a purified yeast enzyme.
A fructose-2,6-bisphosphate dephosphorylating enzyme was 3000-fold purified to electrophoretic homogeneity from Saccharomyces cerevisiae. Half-maximal activity was obtained at pH 6.0 with 6 microM fructose 2,6-bisphosphate and 0.15 mM Mg2+. On incubation for 90 min with fructose 2,6-bisphosphate, about 80% of the substrate appears with an almost linear time dependence as fructose. In the first 30 min a substance accumulates to about 40% of the consumed fructose 2,6-bisphosphate which forms free fructose on mild acid treatment. Formation of fructose 6-phosphate was negligible. The mild-acid-labile intermediate was identified as fructose 2-phosphate by comparative ion-exchange chromatography with authentic fructose 2-phosphate synthesized from fructose 1-phosphate [Pontis, H.G. & Fischer, C.L. (1963) Biochem. J. 89, 452-459]. The data suggest the reaction sequence fructose 2,6-bisphosphate----fructose 2-phosphate----fructose. The designation fructose-2,6-bisphosphate 6-phosphohydrolase is proposed for the enzyme described here.
D000469:Alkaline Phosphatase / Q000378:metabolism; D005632:Fructose / Q000378:metabolism; D005635:Fructosediphosphates / Q000378:metabolism*; D005636:Fructosephosphates / Q000378:metabolism*; D006598:Hexosediphosphates / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008274:Magnesium / Q000378:metabolism; D010732:Phosphofructokinase-1 / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D013997:Time Factors
D005635:Fructosediphosphates; D005636:Fructosephosphates; D006598:Hexosediphosphates; C052127:fructose-2-phosphate; D005632:Fructose; C027618:fructose-6-phosphate; C027652:fructose 2,6-diphosphate; D010732:Phosphofructokinase-1; D000469:Alkaline Phosphatase; D008274:Magnesium