Enzyme kinetics : 6-phosphofructo-2-kinase/2,6-bisphosphatase
نویسندگان
چکیده
ENZYME KINETICS: 6-PHOSPHOFRUCTO-2-KINASE/FRUCTOSE-2,6BISPHOSPHATASE
منابع مشابه
Fructose-2,6-bisphosphatase and 6-phosphofructo-2-kinase are separable in yeast.
Fructose-2,6-bisphosphatase was purified from yeast and separated from 6-phosphofructo-2-kinase and alkaline phosphatase. The enzyme released Pi from the 2-position of fructose 2,6-bisphosphate and formed fructose 6-phosphate in stoichiometric amounts. The enzyme displays hyperbolic kinetics towards fructose 2,6-bisphosphate, with a Km value of 0.3 microM. It is strongly inhibited by fructose 6...
متن کاملOverexpression of 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase in mouse liver lowers blood glucose by suppressing hepatic glucose production.
Hepatic 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase is an important regulatory enzyme of glucose metabolism. By controlling the level of fructose-2,6-bisphosphate, an allosteric activator of the glycolytic enzyme 6-phosphofructo-1-kinase and an inhibitor of the gluconeogenic enzyme fructose-1,6-bisphosphatase, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase regulates hepatic gluco...
متن کاملInactivation of liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase by o-phthalaldehyde.
The two activities of chicken liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase were inactivated by o-phthalaldehyde. Absorbance and fluorescence spectra of the modified enzyme were consistent with the formation of an isoindole derivative (1 mol/mol of enzyme subunit). The inactivation of 6-phosphofructo-2-kinase by o-phthalaldehyde was faster than the inactivation of fructose-2,6-bisp...
متن کاملInduction of rat liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase mRNA by refeeding and insulin.
The effects of fasting/refeeding and untreated or insulin-treated diabetes on the bifunctional enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase and its mRNA in rat liver were determined. Both enzymatic activities fell to 20% of control values with fasting or streptozotocin-induced diabetes and were coordinately restored to normal within 48 h of refeeding or 24 h of insulin administra...
متن کاملContribution of different protein phosphatases to the dephosphorylation of 6-phosphofructo-1-kinase and 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase in rat liver.
The nature of rat liver protein phosphatases involved in the dephosphorylation of the glycolytic key enzyme 6-phosphofructo-1-kinase and the regulatory enzyme 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase was investigated. In terms of the classification system proposed by Ingebritsen & Cohen [(1983) Eur. J. Biochem. 132, 255-261], only the type-2 protein phosphatases 2A (which can be sep...
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