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  • metabolism
  • Rather than inhibiting PEPCK or other gluconeogenic enzymes directly, metformin appears to reduce the gluconeogenic potential of liver by impairing hepatic energy metabolism . (diabetesincontrol.com)
  • In each of these organs it plays an important role in the regulation of carbohydrate metabolism by acting as a glucose sensor, triggering shifts in metabolism or cell function in response to rising or falling levels of glucose, such as occur after a meal or when fasting. (wikipedia.org)
  • The high glucose metabolism of cancer cells is caused by a combination of hypoxia-responsive transcription factors, activation of oncogenic proteins, and the loss of the tumor suppressor function. (scirp.org)
  • Altered glucose metabolism in cancer cells was discovered almost 100 years ago, when Otto Warburg demonstrated that tumours, instead of fully oxidising glucose to CO 2 , switch to aerobic glycolysis and ferment glucose to lactate ( Warburg, 1924 ). (biologists.org)
  • GKRP binds and moves glucokinase (GK), thereby controlling both activity and intracellular location of this key enzyme of glucose metabolism. (wikipedia.org)
  • Researchers have employed physiological studies, microbiological chemistry, enzyme assays, genome sequencing, transcriptomics, and 13 C-based metabolomics/fluxomics to investigate central carbon metabolism and enzymes that operate in phototrophs. (frontiersin.org)
  • In this report, we review diverse CO 2 assimilation pathways, acetate assimilation, carbohydrate catabolism, the tricarboxylic acid cycle and some key, and/or unconventional enzymes in central carbon metabolism of phototrophic microorganisms. (frontiersin.org)
  • hexose
  • Alternative names for this enzyme are: human hexokinase IV, hexokinase D, and ATP:D-hexose 6-phosphotransferase, EC 2.7.1.1 (previously 2.7.1.2). (wikipedia.org)
  • Therefore, the general glucokinase reaction is more accurately described as: Hexose + MgATP2− → hexose-PO2− 3 + MgADP− + H+ Among the hexose substrates are mannose, fructose, and glucosamine, but the affinity of glucokinase for these requires concentrations not found in cells for significant activity. (wikipedia.org)
  • glyceraldehyde-3-phosphate d
  • Further indications came from the observation that glucose continued to be metabolized in tissues even in the presence of glycolysis inhibitors, such as fluoride and iodoacetate ions, inhibitors of enolase (EC 4.2.1.11) and glyceraldehyde 3-phosphate dehydrogenase (EC 1.2.1.12), respectively. (tuscany-diet.net)
  • hydrolysis
  • The hydrolysis of fructose 2,6-biphosphate is likely to follow the below steps: Histidine acts as a nucleophile and attacks the 2-phosphate of F-2,6-BP The stabilization of pentacoordinated transition state by several salt bridges and hydrogen bonding. (wikipedia.org)
  • synthesis
  • Glucokinase has a lower affinity for glucose than the other hexokinases do, and its activity is localized to a few cell types, leaving the other three hexokinases as more important preparers of glucose for glycolysis and glycogen synthesis for most tissues and organs. (wikipedia.org)
  • During periods of ample glucose supply, most GK activity can be found in the peripheral cytoplasm where glycogen synthesis is occurring. (wikipedia.org)
  • Note: In vertebrates, about half of the NADPH necessary for the reductive steps of fatty acid synthesis derives from the pentose phosphate pathway, and the rest from the malic enzyme (EC 1.1.1.40) reaction. (tuscany-diet.net)
  • uptake
  • 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)
  • for this reason it is now being added to some energy drinks to provide a greater rate of carbohydrate uptake than can be achieved with glucose. (thefreedictionary.com)
  • lactate
  • The contribution of Cori cycle lactate to overall glucose production increases with fasting duration. (wikipedia.org)
  • Despite these findings, it is considered unlikely that the 2-carbon acetyl-CoA derived from the oxidation of fatty acids would produce a net yield of glucose via the citric acid cycle - however, acetyl-CoA can be converted into pyruvate and lactate through the ketogenic pathway. (wikipedia.org)
  • molecule
  • On the other hand, when the glucose level increases, the level of fructose 6-phosphate (F6P) subsequently rises and the molecule stimulates phosphoprotein phosphatase-1, which removes phosphoryl group from the bifunctional protein. (wikipedia.org)
  • acetyl groups can only form part of the glucose molecules (not the 5th carbon atom) and require extra substrates (such as pyruvate) in order to form the rest of the glucose molecule. (wikipedia.org)
  • A molecule that is half sucrose and half glucose, which has been promoted as a sugar substitute. (thefreedictionary.com)
  • insulin
  • As a phosphoprotein phosphatase, insulin dephosphorylates the enzyme, thus activating the PFK-2 and inhibiting the FBPase-2 activities. (wikipedia.org)
  • Phosphofructokinase‐2 (PFK‐2), a central regulator of cardiac glycolysis that is normally activated in response to adrenergic stimulation and/or insulin signaling, is decreased in mouse models of reduced insulin signaling, including type 1 diabetes mellitus, high‐fat feeding, and overnight fasting. (ahajournals.org)
  • via Protein Phosphatase and PFK2, insulin increases [F-2,6-BP], which activates glycolysis by allosteric activation of PFK1, signalling an abundance of glucose PFK2 is likely to catalyze the "simple" transfer of γ-phosphoryl group of ATP onto the hydroxyl present on C-2 of fructose-6-phosphate. (wikipedia.org)
  • Its effect is opposite to that of insulin, which lowers the extracellular glucose. (wikipedia.org)
  • Insulin allows glucose to be taken up and used by insulin-dependent tissues. (wikipedia.org)
  • As glucose and insulin levels rise, as during digestion of a meal, GK is released from GKRP and moves back to the cytoplasm, where much of it associates with the bifunctional enzyme. (wikipedia.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)
  • pyruvate
  • For example, the pathway leading from pyruvate to glucose-6-phosphate requires 4 molecules of ATP and 2 molecules of GTP to proceed spontaneously. (wikipedia.org)
  • pentose phospha
  • Hypoglycolytic RA T cells diverted glucose toward the pentose phosphate pathway, generated more NADPH, and consumed intracellular reactive oxygen species (ROS). (rupress.org)
  • increases
  • Having an increased level of GLUT1, in the case of hypoxic tumors, increases the flux of glucose into the cells allowing for a higher rate of glycolysis and thus greater risks of metastasis (as elaborated upon below). (wikipedia.org)
  • humans
  • The existence of glyoxylate cycles in humans has not been established, and it is widely held that fatty acids cannot be converted to glucose in humans directly. (wikipedia.org)
  • amounts of glucose
  • Rising amounts of glucose coming into the hepatocyte prompt the GKRP to rapidly release GK to return to the cytoplasm. (wikipedia.org)
  • Naive CD4 T cells from RA patients failed to metabolize equal amounts of glucose as age-matched control cells, generated less intracellular ATP, and were apoptosis-susceptible. (rupress.org)
  • glucokinase
  • The latter catalyzes the formation and degradation of fructose-2,6-bisphosphate (fructose-2,6-P 2 ) and is a glucokinase-binding protein. (physiology.org)
  • 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)
  • 8 ) showed that PFK2 binds to glucokinase through the bisphosphatase domain. (physiology.org)
  • The common name, glucokinase, is derived from its relative specificity for glucose under physiologic conditions. (wikipedia.org)
  • Two important kinetic properties distinguish glucokinase from the other hexokinases, allowing it to function in a special role as glucose sensor. (wikipedia.org)
  • Glucokinase has a lower affinity for glucose than the other hexokinases. (wikipedia.org)
  • Glucokinase is not inhibited by its product, glucose-6-phosphate. (wikipedia.org)
  • Another distinctive property of glucokinase is its moderate cooperativity with glucose, with a Hill coefficient (nH) of about 1.7. (wikipedia.org)
  • Because of this cooperativity, the kinetic interaction of glucokinase with glucose does not follow classical Michaelis-Menten kinetics. (wikipedia.org)
  • protein
  • The monomers of the bifunctional protein are clearly divided into two functional domains. (wikipedia.org)
  • Endoplasmic reticulum to nuclei-1 signaling enzyme (ERN1) is an endoplasmic reticulum-resident transmembrane protein acting as a proximal sensor of a complex set of signaling pathways named the unfolded protein response. (scirp.org)
  • PFK2
  • however, like PFK2, it had a relative modest effect on the fructose-2,6-P 2 content. (physiology.org)
  • Finally, N-terminal region modulates PFK2 and FBPase2 activities, and stabilizes the dimer form of the enzyme. (wikipedia.org)
  • Regulation
  • The expression of different vascular endothelial growth factor (VEGF) genes was studied in glioma U87 cells with endoplasmic reticulum-nuclei-1 (ERN1) loss of function and its regulation by hypoxia and glutamine or glucose deprivation conditions as model of ischemia. (scirp.org)
  • A better understanding of the α-cell physiology is necessary for an integral comprehension of the regulation of glucose homeostasis and the development of diabetes. (bioscientifica.com)
  • PFKFB3 silencing and overexpression identified a novel extraglycolytic role of the enzyme in autophagy regulation. (rupress.org)
  • binds
  • Fructose 6-phosphate binds to the same site of GKRP, but enhances the ability of GKRP to bind and inactivate GK. (wikipedia.org)
  • diabetes
  • Although this may be beneficial in the fasted state to conserve systemic glucose, it represents a pathological impairment in diabetes mellitus. (ahajournals.org)
  • Warburg
  • The first evidence of the existence of the phosphogluconate pathway was obtained in the 1930s by the studies of Otto Warburg , Nobel Prize in Physiology or Medicine in 1931, who discovered NADP during studies on the oxidation of glucose 6-phosphate to 6-phosphogluconate . (tuscany-diet.net)
  • Insulin
  • Phosphofructokinase‐2 (PFK‐2), a central regulator of cardiac glycolysis that is normally activated in response to adrenergic stimulation and/or insulin signaling, is decreased in mouse models of reduced insulin signaling, including type 1 diabetes mellitus, high‐fat feeding, and overnight fasting. (ahajournals.org)
  • As a phosphoprotein phosphatase, insulin dephosphorylates the enzyme, thus activating the PFK-2 and inhibiting the FBPase-2 activities. (wikipedia.org)
  • As glucose and insulin levels rise, as during digestion of a meal, GK is released from GKRP and moves back to the cytoplasm, where much of it associates with the bifunctional enzyme. (wikipedia.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)
  • via Protein Phosphatase and PFK2, insulin increases [F-2,6-BP], which activates glycolysis by allosteric activation of PFK1, signalling an abundance of glucose PFK2 is likely to catalyze the "simple" transfer of γ-phosphoryl group of ATP onto the hydroxyl present on C-2 of fructose-6-phosphate. (wikipedia.org)
  • Its effect is opposite to that of insulin, which lowers the extracellular glucose. (wikipedia.org)
  • Insulin allows glucose to be taken up and used by insulin-dependent tissues. (wikipedia.org)
  • regulation
  • The expression of different vascular endothelial growth factor (VEGF) genes was studied in glioma U87 cells with endoplasmic reticulum-nuclei-1 (ERN1) loss of function and its regulation by hypoxia and glutamine or glucose deprivation conditions as model of ischemia. (scirp.org)
  • A better understanding of the α-cell physiology is necessary for an integral comprehension of the regulation of glucose homeostasis and the development of diabetes. (bioscientifica.com)
  • PFKFB3 silencing and overexpression identified a novel extraglycolytic role of the enzyme in autophagy regulation. (rupress.org)