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  • catalytic
  • There are two classes of fructose-bisphosphate aldolases with different catalytic mechanisms: class I enzymes [ PMID: 3355497 ] do not require a metal ion, and are characterised by the formation of a Schiff base intermediate between a highly conserved active site lysine and a substrate carbonyl group, while the class II enzymes require an active-site divalent metal ion. (ebi.ac.uk)
  • In mammalian aldolase, the key catalytic amino acid residues involved in the reaction are lysine and tyrosine. (wikipedia.org)
  • glucose
  • Aldolase has also been implicated in many "moonlighting" or non-catalytic functions, based upon its binding affinity for multiple other proteins including F-actin, α-tubulin, light chain dynein, WASP, Band 3 anion exchanger, phospholipase D (PLD2), glucose transporter GLUT4, inositol trisphosphate, V-ATPase and ARNO (a guanine nucleotide exchange factor of ARF6). (wikipedia.org)
  • Here, we describe an AMP/ADP-independent mechanism that triggers AMPK activation by sensing the absence of fructose-1,6-bisphosphate (FBP), with AMPK being progressively activated as extracellular glucose and intracellular FBP decrease. (xmu.edu.cn)
  • Knockdown of aldolases activates AMPK even in cells with abundant glucose, whereas the catalysis-defective D34S aldolase mutant, which still binds FBP, blocks AMPK activation. (xmu.edu.cn)
  • This means that fructose has the same fate as glucose after it gets metabolised. (wikipedia.org)
  • The mechanism that GPI uses to interconvert glucose 6-phosphate and fructose 6-phosphate (aldose to ketose) consists of three major steps: opening the glucose ring, isomerizing glucose into fructose through an enediol intermediate, and closing the fructose ring. (wikipedia.org)
  • Unlike glucose, which is metabolized widely in the body, fructose is metabolized almost completely in the liver in humans, where it is directed toward replenishment of liver glycogen and triglyceride synthesis. (wikipedia.org)
  • 29% - 54% of fructose is converted in liver to glucose, and about quarter of fructose is converted to lactate. (wikipedia.org)
  • Unlike glucose, fructose is not an insulin secretagogue, and can in fact lower circulating insulin. (wikipedia.org)
  • Fructose is metabolized almost completely in the liver in humans, and is directed toward replenishment of liver glycogen and triglyceride synthesis, while much of dietary glucose passes through the liver and goes to skeletal muscle, where it is metabolized to CO2, H2O and ATP, and to fat cells where it is metabolized primarily to glycerol phosphate for triglyceride synthesis as well as energy production. (wikipedia.org)
  • Fructose is replaced in the diet by glucose, maltose or other sugars. (wikipedia.org)
  • substrate
  • There are two classes of fructose-bisphosphate aldolases with different catalytic mechanisms: class I enzymes [ PMID: 3355497 ] do not require a metal ion, and are characterised by the formation of a Schiff base intermediate between a highly conserved active site lysine and a substrate carbonyl group, while the class II enzymes require an active-site divalent metal ion. (ebi.ac.uk)
  • Residue Glu187 participates in multiple functions, including FBP aldolase catalysis, acid-base catalysis during substrate binding, dehydration, and substrate cleavage. (wikipedia.org)
  • Slight differences in isozyme structure result in different activities for the two substrate molecules: FBP and fructose 1-phosphate. (wikipedia.org)
  • reaction
  • The fructose-1,6-bisphosphate aldolases: same reaction, different enzymes. (ebi.ac.uk)
  • The word aldolase also refers, more generally, to an enzyme that performs an aldol reaction (creating an aldol) or its reverse (cleaving an aldol), such as the one[which? (wikipedia.org)
  • In both pathways 3-phosphoglycerate (3-PGA or 3-PG) is reduced to fructose 1,6-bisphosphate with aldolase catalyzing the last reaction. (wikipedia.org)
  • A fifth reaction, catalyzed in both pathways by fructose 1,6-bisphosphatase, hydrolyzes the fructose 1-6-bisphosphate to fructose 6-phosphate and inorganic phosphate. (wikipedia.org)
  • This enzyme catalyses the following chemical reaction 3 S-adenosyl-L-methionine + [fructose-bisphosphate aldolase]-L-lysine ⇌ {\displaystyle \rightleftharpoons } 3 S-adenosyl-L-homocysteine + [fructose-bisphosphate aldolase]-N6,N6,N6-trimethyl-L-lysine The enzyme methylates a conserved lysine in the C-terminal part of higher plant fructose-bisphosphate aldolase (EC 4.1.2.13). (wikipedia.org)
  • In mammalian aldolase, the key catalytic amino acid residues involved in the reaction are lysine and tyrosine. (wikipedia.org)
  • Fructose bisphosphatase catalyses the reverse of the reaction which is catalysed by phosphofructokinase in glycolysis. (wikipedia.org)
  • These enzymes only catalyse the reaction in one direction each, and are regulated by metabolites such as fructose 2,6-bisphosphate so that high activity of one of the two enzymes is accompanied by low activity of the other. (wikipedia.org)
  • The generic fructose bisphosphate aldolase enzyme cleaves a 6-carbon fructose sugar into two 3-carbon products in a reverse aldol reaction. (wikipedia.org)
  • Chi-Huey Wong and co-workers had shown that 2-deoxyribose-5-phosphate aldolase and fructose-1, 6-diphosphate aldolase could be used together in a one-pot reaction to connect two aldehydes and one ketone together through sequential aldol reacations. (wikipedia.org)
  • bisphosphate
  • Fructose-bisphosphate aldolases: an evolutionary history. (ebi.ac.uk)
  • Fructose-bisphosphate aldolase)-lysine N-methyltransferase (EC 2.1.1.259, rubisco methyltransferase, ribulose-bisphosphate-carboxylase/oxygenase N-methyltransferase, ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit epsilonN-methyltransferase, S-adenosyl-L-methionine:[3-phospho-D-glycerate-carboxy-lyase (dimerizing)]-lysine 6-N-methyltransferase) is an enzyme with systematic name S-adenosyl-L-methionine:(fructose-bisphosphate aldolase)-lysine N6-methyltransferase. (wikipedia.org)
  • Unqualified, aldolase usually refers to the enzyme fructose-bisphosphate aldolase. (wikipedia.org)
  • This gene encodes a member of the class I fructose-bisphosphate aldolase gene family. (wikipedia.org)
  • 6-deoxy-5-ketofructose 1-phosphate synthase (EC 2.2.1.11, DKFP synthase, MJ1585 (gene)) is an enzyme with systematic name 2-oxopropanal:D-fructose 1,6-bisphosphate glycerone-phosphotransferase. (wikipedia.org)
  • More specifically, fructose 2,6-bisphosphate allosterically inhibits fructose 1,6-bisphosphatase, but activates phosphofructokinase-I. Fructose 1,6-bisphosphatase is involved in many different metabolic pathways and found in most organisms. (wikipedia.org)
  • Fructose 1,6-bisphosphate Fructose 6-phosphate Click on genes, proteins and metabolites below to link to respective articles. (wikipedia.org)
  • When sensitivity to allosteric inhibitors such as AMP, ADP, inorganic phosphate, and fructose-2,6-bisphosphate were examined, FBPase from hibernating bats was much more sensitive to inhibitors at low temperature than in euthermic bats. (wikipedia.org)
  • One of the most important glycolytic genes is fructose-1,6-bisphosphate aldolase (fbaA). (wikipedia.org)
  • cleavage
  • After Schiff base formation, the fourth hydroxyl group on the fructose backbone is then deprotonated by an aspartate residue (aspartate 33), which results in an aldol cleavage. (wikipedia.org)
  • precursors
  • Affected individuals are asymptomatic and healthy, provided they do not ingest foods containing fructose or any of its common precursors, sucrose and sorbitol. (wikipedia.org)
  • Stable patients without acute intoxication events are treated by careful dietary planning that avoids fructose and its metabolic precursors. (wikipedia.org)
  • enzymes
  • The fructose 1,6-bisphosphatases found within the Firmicutes (low GC Gram-positive bacteria) do not show any significant sequence similarity to the enzymes from other organisms. (wikipedia.org)
  • metabolic
  • Fructose 1,6-bisphosphatase also plays a key role in hibernation, which requires strict regulation of metabolic processes to facilitate entry into hibernation, maintenance, arousal from hibernation, and adjustments to allow long-term dormancy. (wikipedia.org)
  • Schiff
  • the formation of a Schiff base is the key differentiator between Class I (produced by animals) and Class II (produced by fungi and bacteria) aldolases. (wikipedia.org)
  • sucrose
  • In the past, infants often became symptomatic when they were introduced to formulas that were sweetened with fructose or sucrose. (wikipedia.org)
  • Once identified, parents of infants who carry mutant aldolase B alleles leading to HFI, or older individuals who have clinical histories compatible with HFI can be identified and counselled with regard to preventive therapy: dietary exclusion of foods containing fructose, sucrose, or sorbitol. (wikipedia.org)
  • pathway
  • These results suggest that the activation of glycolytic pathway function accelerates root growth and that GA3-induced root aldolase may be modulated through OsCDPK13. (deepdyve.com)
  • Diagnostic
  • If possible, individuals who suspect they might have HFI, should avoid testing via fructose challenge as the results are non-conclusive for individuals with HFI and even if the diagnostic administration fructose is properly controlled, profound hypoglycemia and its sequelae can threaten the patient's well-being. (wikipedia.org)