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  • Phosphorylation
  • Glycolysis Step 2 Voet, Voet & Pratt 20012 Fig. 15.3 Phosphorylation of Fructose 6-P G= -14.2 kJ/mol Glycolysis Step 3 Berg, Tymoczko & Stryer, 2012 Chap 16 Stage 2 of Glycolysis Berg, Tymoczko & Stryer, 2002 chap 16. (slidegur.com)
  • The liver isoform is regulated by phosphorylation of a serine residue at the NH 2 terminus (Ser-32) by cAMP-dependent protein kinase, which leads to an increase in the bisphosphatase-to-kinase activity ratio. (physiology.org)
  • amino acids stimulate Fru-2,6-P2 synthesis by Akt-dependent PFKFB2 phosphorylation and activation and show how signaling and metabolism are inextricably linked. (nih.gov)
  • Enzyme
  • the bifunctional enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFK2) catalyzes both the formation of fructose-2,6-bisphosphate (fructose-2,6-P 2 ) and its degradation ( 26 , 27 , 35 ). (physiology.org)
  • This protein regulates fructose-2,6-bisphosphate levels in the heart, while a related enzyme encoded by a different gene regulates fructose-2,6-bisphosphate levels in the liver and muscle. (nih.gov)
  • protein
  • Binding of glucokinase to glucokinase regulatory protein is counteracted by fructose-1-phosphate, and accordingly precursors of fructose-1-phosphate cause translocation of glucokinase from the nucleus to the cytoplasm ( 2 , 33 ). (physiology.org)
  • This PFK2 variant, when expressed at high levels, reverses the inhibitory effects of glucagon on glycolysis, fructose-2,6-P 2 , and glucokinase translocation, indicating a role for either PFK2 protein or its product fructose-2,6-P 2 in mediating the effects of glucagon. (physiology.org)
  • increase
  • A persistent increase in 6-phosphofructo-2-kinase produced by a change in PFK-2/FBPase-2 isoform expression that may play an important role in the regulation of muscle glycolysis. (nih.gov)
  • glucose
  • 2. The attachment of the phosphoryl group renders glucose a less stable molecule and more amenable to further metabolic action. (slidegur.com)
  • liver
  • bifunctionality of PFK-2/FBPase-2 complements the metabolic zonation of the liver by ensuring coherent switching in response to insulin and glucagon. (nih.gov)
  • levels
  • However, combined overexpression of glucokinase and PFK2 had a synergistic effect on fructose-2,6-P 2 levels, suggesting that interaction of these enzymes may be a prerequisite for formation of fructose-2,6-P 2 . (physiology.org)
  • PFK2
  • however, like PFK2, it had a relative modest effect on the fructose-2,6-P 2 content. (physiology.org)
  • PFK exists as a homotetramer in bacteria and mammals (where each monomer possesses 2 similar domains) and as an octomer in yeast (where there are 4 alpha- (PFK1) and 4 beta-chains (PFK2), the latter, like the mammalian monomers, possessing 2 similar domains). (wikipedia.org)
  • Reaction
  • ATP acts as an allosteric inhibitor and when cellular concentrations of ATP are high, and the cell's energy needs are low, the reaction catalyzed by 1-phosphofructokinase is inhibited. (wikipedia.org)
  • The catalyzed mutase reaction involves two separate phosphoryl groups and the ending phosphate on the 2-carbon is not the same phosphate removed from the 3-carbon. (wikipedia.org)
  • The site contains 3 crucial amino acids (2 histidines and 1 glutamic acid ) that are involved in the phosphatase reaction. (wikipedia.org)
  • glucose
  • A short‐term decrease of PFK‐2 during fasting would contribute to limited glucose use basally and in response to β‐adrenergic signaling. (ahajournals.org)
  • However, variant forms of GCKR have been found to be associated with small differences in levels of glucose, insulin, triglycerides, C-reactive protein, and higher or lower risks for type 2 diabetes mellitus. (wikipedia.org)
  • Allosteric regulation of 1-phosphofructokinase is facilitated hormonally to help the liver to maintain blood glucose levels. (wikipedia.org)
  • It catalyses the removal of a phosphate group from fructose-2,6-bisphosphate (F-2,6-BP): Fructose-2,6-Bisphosphate->Fructose-6-phosphate (F-6-P) + phosphate F-2,6-BP is an allosteric regulator of cellular glucose metabolism pathways. (wikipedia.org)
  • Increased expression of hexokinase 2, in some cases nearly 10-fold, allows for an increased flux of glucose through the glycolytic pathway subsequent to the increased uptake by GLUT1. (wikipedia.org)
  • Gene
  • 2-dehydro-3-deoxygluconokinase ( EC:2.7.1.45 ) (gene: kdgK). (ebi.ac.uk)
  • Sequence similarities between the gene specifying 1-phosphofructokinase (fruK), genes specifying other kinases in Escherichia coli K12, and lacC of Staphylococcus aureus. (ebi.ac.uk)
  • It is coded for by a 19 exon gene, GCKR, on the short arm of chromosome 2 (2p23). (wikipedia.org)
  • protein
  • Binding of glucokinase to glucokinase regulatory protein is counteracted by fructose-1-phosphate, and accordingly precursors of fructose-1-phosphate cause translocation of glucokinase from the nucleus to the cytoplasm ( 2 , 33 ). (physiology.org)
  • Both type 1 diabetes mellitus and a high‐fat diet induced a significant decrease in cardiac PFK‐2 protein content without affecting its transcript levels. (ahajournals.org)
  • Protein Sci 1993, 2: 31-40. (wikipedia.org)
  • binds
  • and in an 'open' state, the magnesium ion binds only the ADP, as the 2 products are now further apart. (wikipedia.org)
  • molecules
  • Anionic molecules such as vanadate, acetate, chloride ion, phosphate, 2-phosphoglycolate, and N-[tris(hydroxymethyl)methyl-2-amino]ethanesulfonate are known inhibitors of the mutase activity of dPGM. (wikipedia.org)
  • decrease
  • Overnight fasting also induced a decrease in PFK‐2, suggesting it is rapidly degraded in the absence of insulin signaling. (ahajournals.org)
  • A long‐term decrease in PFK‐2 could increase cardiac metabolic inflexibility and contribute to diabetic heart disease. (ahajournals.org)
  • regulation
  • The key difference between the regulation of PFK in eukaryotes and prokaryotes is that in eukaryotes PFK is activated by fructose 2,6-bisphosphate. (wikipedia.org)
  • The concentration of Fru-2,6-P2 in cells is controlled through regulation of the synthesis and breakdown by PFK-2/FBPase-2. (wikipedia.org)
  • Fru-2,6-P2 plays an important role in the regulation of triose phosphates, the end products of the Calvin Cycle. (wikipedia.org)
  • glycolytic
  • An unbiased metabolomic study demonstrated that decreased PFK‐2 in fasted animals is accompanied by an increase in glycolytic intermediates upstream of phosphofructokianse‐1, whereas those downstream are diminished. (ahajournals.org)
  • affects
  • Methods and Results Streptozotocin‐induced diabetes mellitus, high‐fat diet feeding, and fasted mice were used to identify how decreased insulin signaling affects PFK‐2 and cardiac metabolism. (ahajournals.org)
  • normally
  • Cardiac PFK‐2 levels normally fluctuate dynamically between the fed and fasted states, but they are persistently decreased with diabetes mellitus and a high‐fat diet. (ahajournals.org)