Phosphofructo kinase from

T. Kawakami, R. Ohshima, T. ADP-dependent glucokinase/phosphofructo-kinase, a novel bifunctional enzyme from the hyperthermophilic archaeon Methanococcus jannaschii. J. Biol. Chem., Til, 12495-12498 (2002)... 

Figure 4 Comparison of freeze/thaw stability with freeze/dry stability phosphofructo-kinase with additives at 0.5 M. Hatched bar, freeze/thaw solid bar, freeze/dry. (Data from [24].)...

Fructose 1,6-bisphosphate has attracted attention due to its important applications in the field of medicine, and is produced from glucose in three step by enzymatic reactions catalyzed by glucokinase, phosphoglucose isomerase, and phosphofructo-kinase. ATP is regenerated by acetate kinase (Fig. 17-26). Ishikawa and coworkers established an efficient method for production of fructose 1,6-bisphosphate in a... 

Du Toit, P.J. Potgieter, D.J.J. De Villiers, V. Properties of 1-phosphofructo-kinase isolated from Clostridium pasteurianum. Enzymologia, 43, 285-300 (1972)... 

Bedri, A. Kretschmer, M. Schellenberger, W. Hofmann, E. Kinetics of 6-phosphofructo-2-kinase from Saccharomyces cerevisiae inhibition of the enzyme by ATP. Biomed. Biochim. Acta, 48, 403-411 (1989)... 

Vasquez-Illanes, M.D. Ramos-Martinez, J.L Phosphorylation-activated 6-phosphofructo-2-kinase from mantle tissue of marine mussels. FEBS Lett., 295, 176-178 (1991)... 

Harmsen, H.J.M. Kubicek-Pranz, E.M. Rohr, M. Visser, J. Kubicek, C.P. Regulation of 6-phosphofructo-2-kinase from the citric-acid-accumulating fungus Aspergillus niger. Appl. Microbiol. BiotechnoL, 37, 784-788 (1992)... 

KInatM enzymes which catalyse the transfer of a phosphate residue (strictly speaking a phosphoryl group is transferred) from ATP to another substrate, in particular to the alcoholic hydroxyl groups of monosaccharides. Some important K. are hexokinase, which phosphorylates several hexoses at the C6 position, glucokinase, which is responsible for glucose 6-phosphate formation in the liver, and phosphofructo-kinase. 

This enzyme [EC 2.7.1.11], also known as phosphohexo-kinase and phosphofructokinase 1, catalyzes the reaction of ATP with D-fructose 6-phosphate to produce ADP and D-fructose 1,6-bisphosphate. Both D-tagatose 6-phosphate and sedoheptulose 7-phosphate can act as the sugar substrate. UTP, CTP, GTP, and ITP all can act as the nucleotide substrate. This enzyme is distinct from that of 6-phosphofructo-2-kinase. See also ATP GTP Depletion... 

The membrane-associated Akt kinase is now a substrate for protein kinase PDKl that phosphorylates a specific Thr and Ser residue of Akt kinase. The double phosphorylation converts Akt kinase to the active form. It is assumed that the Akt kinase now dissociates from the membrane and phosphorylates cytosolic substrates such as glycogen synthase kinase, 6-phosphofructo-2-kinase and ribosomal protein S6 kinase, p70 . According to this mechanism, Akt kinase regulates central metabolic pathways of the cell. Furthermore, it has a promoting influence on cell division and an inhibitory influence on programmed cell death, apoptosis. A role in apoptosis is suggested by the observation that a component of the apoptotic program. Bad protein (see Chapter 15) has been identified as a substrate of Akt kinase. 

The effects of ATP, AMP, and fructose 2,6-bisphos-phate on phosphofructokinase have been discussed in Chapter 11, Section C. Fructose 2,6-P2 is a potent allosteric activator of phosphofructokinase and a strong competitive inhibitor of fructose 1,6-bisphosphatase (Fig. 11-2). It is formed from fructose 6-P and ATP by the 90-kDa bifunctional phosphofructo-2-kinase/ fructose 2,6-bisphosphatase. Thus, the same protein forms and destroys this allosteric effector. Since the bifunctional enzyme is present in very small amounts, the rate of ATP destruction from the substrate cycling is small. 

Kountz, P.D. El-Maghrabi, M.R. Pilkis, S.J. Isolation and characterization of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase from bovine liver. Arch. Biochem. Biophys., 238, 531-543 (1985)... 

Pyko, M. Rider, M.H. Hue, L. Wegener, G. 6-Phosphofructo-2-kinase/ fructose-2,6-bisphosphatase from frog skeletal muscle purification, kinetics and immunological properties. J. Comp. Physiol. B, 163, 89-98 (1993)... 

Bertrand, L. Alessi, D.R. Deprez, J. Deak, M. Viaene, E. Rider, M.H. Hue, L. Heart 6-phosphofructo-2-kinase activation by insulin results from Ser-466 and Ser-483 phosphorylation and requires 3-phosphoinositide-depen-dent kinase-1, but not protein kinase B. J. Biol. Chem., 274, 30927-30933 (1999)... 

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