Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:4.1.2.13 (aldolase)
3,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Skeletal muscle triads are possessing the whole set of enzymes of the phosphatidylinositol (PI)-linked signal generating pathway, PI-kinase, PI(4)P-kinase, and PI(4,5)P2-phospholipase C (PLC). The activities of these enzymes are comparable to those found in other cell types for which a functional role of the PI-pathway in intracellular signal transduction has been established. For skeletal muscle an unequivocal function and an initiating signal for Ins(1,4,5)P3-liberation is still unknown. However, the observed Ca-dependency of PLC activity suggests that here Ins(1,4,5)P3 production is a consequence rather than a cause of increasing cytosolic Ca2+. Recently, the glycolytic enzyme aldolase, whose activity can be modulated by inositol polyphosphates, has been localized in the triadic structure. The enzyme which has a high affinity to Ins(1,4)P2, Ins(1,4,5)P3 and Ins(1,3,4,5)P4, seems to be compartmentalized to the junctional foot structure from which it is released upon binding of these molecules. This phenomenon could reflect a capability for regulation of the glycolytic flux even for aldolase, especially if a non steady-state situation in the junctional gap is considered. Meanwhile we have accumulated evidence for the operation of a partial glycolytic sequence in the junctional region established by the enzymes aldolase, glyceraldehyde-3-P (GAP) dehydrogenase and phosphoglycerate kinase. This system is able to produce ATP upon oxidation of GAP and could be, because of the inositol polyphosphate-sensing abilities of aldolase, a target for the membrane associated PI-pathway. The ATP production is however transient which indicates the coupling to an ATP hydrolyzing reaction.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Relation of phosphatidylinositol metabolism to glycolytic pathway in skeletal muscle membranes. 228 42

To investigate a possible chromosomal clustering of glycolytic enzyme genes, the complete nucleotide sequence of the 8029 bp insert of Escherichia coli DNA in the ColE1 plasmid pLC33-5 of the Clarke and Carbon collection (Clark and Carbon, 1976) was determined. Genes (pgk, fda) encoding the phosphoglycerate kinase and Class II fructose 1,6-bisphosphate aldolase, respectively, of E. coli were identified. The phosphoglycerate kinase was found to be highly homologous in primary structure to the same enzyme from eukaryotic organisms. A further large open reading frame, designated gapB, was also identified, which on the basis of sequence homology, appears to encode another glycolytic enzyme, glyceraldehyde 3-phosphate dehydrogenase. This putative gene differs significantly from that (designated gapA) already identified as coding for this enzyme in E. coli and which maps elsewhere on the chromosome. The products, if any, of several other open reading frames remain to be identified.
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PMID:Identification, molecular cloning and sequence analysis of a gene cluster encoding the class II fructose 1,6-bisphosphate aldolase, 3-phosphoglycerate kinase and a putative second glyceraldehyde 3-phosphate dehydrogenase of Escherichia coli. 254 7

Interactions of the glycolytic enzymes glucose-6-phosphate isomerase, aldolase, glyceraldehyde-3-phosphate dehydrogenase, triose-phosphate isomerase, enolase, phosphoglycerate mutase, phosphoglycerate kinase, pyruvate kinase, lactate dehydrogenase type-M, and lactate dehydrogenase type-H with tubulin and microtubules were studied. Lactate dehydrogenase type-M, pyruvate kinase, glyceraldehyde-3-phosphate dehydrogenase, and aldolase demonstrated the greatest amount of co-pelleting with microtubules. The presence of 7% poly(ethylene glycol) increased co-pelleting of the latter four enzymes and two other enzymes, glucose-6-phosphate isomerase, and phosphoglycerate kinase with microtubules. Interactions also were characterized by fluorescence anisotropy. Since the KD values of glyceraldehyde-3-phosphate dehydrogenase, pyruvate kinase and lactate dehydrogenase for tubulin and microtubules were all found to be between 1 and 4 microM, which is in the range of enzyme concentration in cells, these enzymes are probably bound to microtubules in vivo. These observations indicate that interactions of cytosolic proteins, such as the glycolytic enzymes, with cytoskeletal components, such as microtubules, may play a structural role in the formation of the microtrabecular lattice.
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PMID:Glycolytic enzyme interactions with tubulin and microtubules. 255 25

In the past few years, very rapid advances have been made in the field of red cell enzymopathies associated with hereditary nonspherocytic hemolytic anemia, particularly in molecular basis. Nucleotide sequence and amino acid sequence of normal human red cell enzymes have been clarified in phosphofructokinase, aldolase, triosephosphate isomerase, phosphoglycerate kinase, pyruvate kinase, diphosphoglycerate mutase, glucose 6-phosphate dehydrogenase, adenylate kinase and adenosine deaminase. Furthermore, in aldolase-, triosephosphate isomerase-, diphosphoglycerate mutase-, glucose 6-phosphate dehydrogenase-, and adenylate kinase deficiency, single nucleotide changes which cause single amino acid substitutions and finally hemolysis, have been found.
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PMID:Molecular basis of red cell enzymopathies associated with hereditary nonspherocytic hemolytic anemia. 256 Apr 52

Since the discovery of glucose-6-phosphate dehydrogenase (G6PD) deficiency and pyruvate kinase deficiency, erythroenzymopathies associated with hereditary hemolytic anemia have been extensively investigated. Kinetic and electrophoretic studies have shown that most erythroenzymopathies are caused by the production of a mutant enzyme. Single amino acid substitutions have been determined in G6PD and phosphoglycerate kinase variants by studies of the enzyme. Except for these two enzymes, it has been difficult to purify and to characterize the patient's enzyme because of the low protein contents in red blood cells. Recent advance in recombinant DNA technology has made possible the isolation of normal genomic DNA or cDNA for several enzymes. These results permit us to study the molecular basis of erythroenzymopathies at the nucleotide level. Single base substitutions have been identified in aldolase, triosephosphate isomerase, G6PD and adenylate kinase variants by the cloning and nucleotide sequence of the patients' genes. To date, all of the enzyme-deficient variants which have been investigated are caused by point mutations. An exception is a hemolytic anemia secondary to increased adenosine deaminase (ADA) activity. Red cell ADA activity increases on the order of a hundred-fold in affected individuals. The basic abnormality appears to result from overproduction of structurally normal enzyme due to abnormal translational efficiency.
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PMID:[Pathophysiology and laboratory tests of hemolytic anemia: with special reference to erythroenzymopathies]. 269 73

The partition behaviour of six enzymes of the Calvin cycle in extracts of chloroplasts from spinach (Spinacia oleracea) between two aqueous phases has been studied by countercurrent distribution. The enzymes showed distribution patterns which indicate heterogeneity and the presence of two or three fractions of most of the enzymes. When two of the enzymes, phosphoglycerate kinase and fructose-bisphosphate aldolase, were partitioned in both purified and partially purified form, they behaved like homogeneous substances. These results indicate that countercurrent distribution of crude extracts in aqueous two-phase systems is a useful method to study protein-protein interaction.
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PMID:Studies of protein-protein interaction using countercurrent distribution in aqueous two-phase systems. Partition behaviour of six Calvin-cycle enzymes from a crude spinach (Spinacia oleracea) chloroplast extract. 273 May 89

Past work, including our computer simulation of cardiac energy metabolism, indicates that magnesium is an important coherent controller of glycolysis and the Krebs cycle. Many of the glycolytic enzymes are sensitive to Mg2+. The most important effect is due to MgATP2-being a cofactor for a number of these enzymes while other chelation forms are inactive or inhibitory. The means by which Mg2+ and Mg2+ chelates of adenine nucleotides regulate the most important glycolytic enzymes--hexokinase, phosphofructokinase, aldolase, phosphoglycerate kinase, and pyruvate kinase--are described in detail. Creatine kinase, which is important in energy metabolism and highly sensitive to both metal ions and pH, is also discussed. It is necessary to properly control the composition of assay mixtures (particularly with regard to metal ions) in order to determine what actually regulates the activity of an enzyme.
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PMID:Magnesium regulation of the glycolytic pathway and the enzymes involved. 293 60

We have developed a method for the simultaneous purification of hexokinase, glucosephosphate isomerase, phosphofructokinase, fructose-1,6-bisphosphate aldolase, triosephosphate isomerase, D-glyceraldehyde-phosphate dehydrogenase, phosphoglycerate kinase, glycerol-3-phosphate dehydrogenase and glycerol kinase from Trypanosoma brucei in yields varying over 8-55%. Crude glycosomes were prepared by differential centrifugation of cell homogenates. Subsequent hydrophobic interaction chromatography on phenyl-Sepharose resulted in six pools containing various mixtures of enzymes. These pools were processed via affinity chromatography (immobilized ATP), hydrophobic interaction chromatography (octyl-Sepharose) and ion-exchange chromatography (CM- and DEAE-cellulose) which resulted in the purification of all nine enzymes. The native enzyme and subunit molecular masses, as determined by gel filtration and gel electrophoresis under denaturing conditions, were compared with those of their homologous counterparts from other organisms. Trypanosomal hexokinase is a hexamer and differs in subunit composition from the mammalian enzymes (monomers) as well as in subunit size (51 kDa versus 96-100 kDa, respectively). Phosphofructokinase only differs in subunit size (51 kDa for T. brucei versus 80-90 kDa for mammals) but had identical subunit composition (tetrameric). The others all have the same subunit composition as their mammalian counterparts. Except for triosephosphate isomerase, all Trypanosoma enzymes have subunits which are 1-5 kDa larger in size. Together these nine enzymes contribute 3.3 +/- 1.6% to the total cellular protein of T. brucei and at least 90% to the total glycosomal protein. A comparison of calculated intraglycosomal concentrations of the enzymes with the glycosomal metabolite concentrations shows that in the case of aldolase, glyceraldehyde-phosphate dehydrogenase and phosphoglycerate kinase, the concentration of active sites is of the same order of magnitude as that of their reactants. A common feature of the glycosomal glycolytic enzymes (with the exception of glucosephosphate isomerase) is that they are highly basic proteins with pI values between 8.8 and 10.2, values which are 1-4 higher than in the case of their mammalian cytosolic counterparts and 3-6 higher than in the case of the various unicellular organisms. It is suggested that both the larger subunit size and the basic character of the T. brucei glycolytic proteins are involved in the routing of the enzymes from their site of biogenesis (the cytosol) towards their site of action (the glycosome).
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PMID:Glycolytic enzymes of Trypanosoma brucei. Simultaneous purification, intraglycosomal concentrations and physical properties. 294 90

Since the discovery of glucose 6-phosphate dehydrogenase (G6PD) and of pyruvate kinase deficiencies, erythroenzymopathies associated with hereditary hemolytic anemia have been extensively investigated. Kinetic and electrophoretic studies have shown that most, if not all, erythroenzymopathies are caused by the production of a mutant enzyme. Except for a few enzymes that are abundant in blood and tissues, it is difficult to obtain enough sample to study the functional and structural abnormalities of mutant enzymes associated with genetic disorders in man. The primary structures of only two normal red cell enzymes which can cause hereditary hemolytic anemia, phosphoglycerate kinase (PGK) and adenylate kinase, have been determined. Single amino acid substitutions of PGK variants have been found, and the identification of the exact molecular abnormalities of such variants has helped us to understand the accompanying functional abnormality. Gene cloning makes possible the identification of the DNA sequence that codes for enzyme proteins. Recently, human complementary DNA (cDNA) for aldolase, PGK, G6PD, and adenosine deaminase (ADA) have been isolated, and the nucleotide sequences for PGK and ADA determined. In the near future, human cDNA sequencing should permit identification of the gene alteration that gives rise to the mutant enzymes.
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PMID:Molecular aspects of erythroenzymopathies associated with hereditary hemolytic anemia. 299 Feb 2

The specific activities of glucosephosphate isomerase, aldolase, triosephosphate isomerase, glyceraldehydephosphate dehydrogenase, phosphoglycerate kinase, phosphoglycerate mutase, pyruvate kinase and lactate dehydrogenase were all higher in the synaptoplasmic fraction from rat brain than in 100,000 g supernatant fraction of rat brain homogenates when the supernatants were prepared in high ionic strength solutions. Four enzymes in synaptosomes and two enzymes in homogenates were associated with particulate fractions as indicated by the large increase in specific activity of the enzymes when samples were treated with 0.3 M KCl before centrifugation. Glucosephosphate isomerase, aldolase, pyruvate kinase and lactate dehydrogenase were the enzymes that showed a large increase in specific activity following salt treatment of isolated, synaptosomal membrane while aldolase and pyruvate kinase were the two enzymes which showed a large increase in specific activity in the high speed supernatant fractions. Because the specific activities of many enzymes are found to be elevated not only in synaptosomes but in synaptosomal membrane fractions it is suggested that these enzymes may provide the potential for significantly enhanced glycolysis at these locations.
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PMID:Glycolytic enzyme levels in synaptosomes. 299 Aug 10


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