Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.2.1.13 (glyceraldehyde-3-phosphate dehydrogenase)
 6,511 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activities of 6 enzymes involved in carbohydrate metabolism were determined quantitatively in preovulatory oocytes by cytochemical means per individual cell as well as biochemically in cell homogenates. Oocytes were incorporated in a polyacrylamide matrix for appropriate enzyme cytochemical staining. This incorporation preserves the morphology of the cells very well, and the enzymes keep their activity for a considerable period of time. This method could also be used to demonstrate more than one enzyme activity in the same cell. The results obtained by cytochemical means appeared to correlate very well with the biochemical data (P less than 0.005). Glucose 6-phosphate dehydrogenase, the key-enzyme in the pentose phosphate pathway, had very high activity in these preovulatory oocytes, but 6-phosphogluconate dehydrogenase activity was only about 2% of that of glucose 6-phosphate dehydrogenase. The activities of lactate dehydrogenase and to a lesser extent glucose phosphate isomerase and D-glyceraldehyde-3-phosphate dehydrogenase also appeared to be very high, while hexokinase showed a very low activity.
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PMID:A cytochemical method for measuring enzyme activity in individual preovulatory mouse oocytes. 241

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

The specific activities of each of the enzymes of the classical pentose phosphate pathway have been determined in both cultured procyclic and bloodstream forms of Trypanosoma brucei. Both forms contained glucose-6-phosphate dehydrogenase (EC 1.1.1.49), 6-phosphogluconolactonase (EC 3.1.1.31), 6-phosphogluconate dehydrogenase (EC 1.1.1.44), ribose-5-phosphate isomerase (EC 5.3.1.6) and transaldolase (EC 2.2.1.2). However, ribulose-5-phosphate 3'-epimerase (EC 5.1.3.1) and transketolase (EC 2.2.1.1) activities were detectable only in procyclic forms. These results clearly demonstrate that both forms of T. brucei can metabolize glucose via the oxidative segment of the classical pentose phosphate pathway in order to produce D-ribose-5-phosphate for the synthesis of nucleic acids and reduced NADP for other synthetic reactions. However, only procyclic forms are capable of using the non-oxidative segment of the classical pentose phosphate pathway to cycle carbon between pentose and hexose phosphates in order to produce D-glyceraldehyde 3-phosphate as a net product of the pathway. Both forms lack the key gluconeogenic enzyme, fructose-bisphosphatase (EC 3.1.3.11). Consequently, neither form should be able to engage in gluconeogenesis nor should procyclic forms be able to return any of the glyceraldehyde 3-phosphate produced in the pentose phosphate pathway to glucose 6-phosphate. This last specific metabolic arrangement and the restriction of all but the terminal steps of glycolysis to the glycosome may be the observations required to explain the presence of distinct cytosolic and glycosomal isoenzymes of glyceraldehyde-3-phosphate dehydrogenase and phosphoglycerate kinase. These same observations also may provide the basis for explaining the presence of cytosolic hexokinase and phosphoglucose isomerase without the presence of any cytosolic phosphofructokinase activity. The key enzymes of the Entner-Doudoroff pathway, 6-phosphogluconate dehydratase (EC 4.2.1.12) and 2-keto-3-deoxy-6-phosphogluconate aldolase (EC 4.1.2.14) were not detected in either procyclic or bloodstream forms of T. brucei.
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PMID:The enzymes of the classical pentose phosphate pathway display differential activities in procyclic and bloodstream forms of Trypanosoma brucei. 292 7

The metabolic pathways of glucose were studied by histochemical reactions in some species of gastropods living in different habitats. The glycolytic pathway is histochemically indicated by positive results for glucose-6-phosphate isomerase, fructose-1,6-biphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, and D-lactate dehydrogenase. The enzymes of the Krebs cycle gave different responses: isocitrate dehydrogenase and L-malate dehydrogenase were positive, whilst succinate dehydrogenase was constantly negative. Malate synthetase activity was also demonstrated. Despite L-glutamate dehydrogenase is undetectable, the presence of transaminase indicates the gluconeogenetic route. Phosphoglucomutase and glucose-6-phosphate phosphatase appear also positive. The metabolic meaning of our results were discussed.
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PMID:Histochemical research on metabolic pathways of glucose in some species of Mollusca Gastropoda. 311 Nov 50

Glycosomes and mitochondrial vesicles from cultured promastigotes of Leishmania mexicana mexicana have been separated using isopycnic centrifugation on linear sucrose gradients. Hexokinase (EC 2.7.1.2), glucose phosphate isomerase (EC 5.3.1.9), phosphofructokinase (EC 2.7.1.11), glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12), and phosphoenolpyruvate carboxykinase (EC 4.1.1.49) were recovered largely in association with glycosomes (density; 1.215 g/ml). Phosphoglycerate kinase (EC 2.7.2.3) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) had some small glycosomal activity, but were mostly recovered in the soluble fractions. Malate dehydrogenase (EC 1.1.1.37) showed a broad peak corresponding to that of the mitochondrial marker oligomycin-sensitive ATPase (EC 3.6.1.4) (density; 1.190 g/ml). Glutamate dehydrogenase (EC 1.4.1.3) and alanine aminotransferase (EC 2.6.1.2) both showed small mitochondrial peaks, but most of the activities were recovered elsewhere on the gradient and in the soluble fractions. The subcellular location of enzymes in L.m. mexicana amastigotes was investigated by following the release of soluble enzymes from digitonin-treated amastigotes. This revealed distinct cytosolic, mitochondrial, and glycosomal compartments. The findings give an insight into the organization and control of L.m. mexicana promastigote and amastigote energy metabolism.
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PMID:Leishmania mexicana: subcellular distribution of enzymes in amastigotes and promastigotes. 315 38

Interactions of glucose-6-phosphate isomerase (D-glucose-6-phosphate ketol-isomerase, EC 5.3.1.9), aldolase (D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate lyase, EC 4.1.2.13), glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC 1.2.1.12), triose-phosphate isomerase (D-glyceraldehyde-3-phosphate ketol-isomerase, EC 5.3.1.1), phosphoglycerate mutase (D-phosphoglycerate 2,3-phosphomutase, EC 5.4.2.1), phosphoglycerate kinase (ATP:3-phospho-D-glycerate 1-phosphotransferase, EC 2.7.3), enolase (2-phospho-D-glycerate hydro-lyase, EC 4.2.1.11), pyruvate kinase (ATP:Pyruvate O2-phosphotransferase, EC 2.7.1.40) and lactate dehydrogenase [S)-lactate:NAD+ oxidoreductase, EC 1.1.1.27) with F-actin, among the glycolytic enzymes listed above, and with phosphofructokinase (ATP:D-fructose-6-phosphate 1-phosphotransferase, EC 2.7.1.11) were studied in the presence of poly(ethylene glycol). Both purified rabbit muscle enzymes and rabbit muscle myogen, a high-speed supernatant fraction containing the glycolytic enzymes, were used to study enzyme-F-actin interactions. Following ultracentrifugation, F-actin and poly(ethylene glycol) tended to increase and KCl to decrease the pelleting of enzymes. In general, the greater part of the pelleting occurred in the presence of both F-actin and poly(ethylene glycol) and the absence of KCl. Enzymes that pelleted more in myogen preparations than as individual purified enzymes in the presence of poly(ethylene glycol) and the absence of F-actin were tested for specific enzyme-enzyme associations, several of which were observed. Such interactions support the view that the internal cell structure is composed of proteins that interact with one another to form the microtrabecular lattice.
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PMID:Heteromerous interactions among glycolytic enzymes and of glycolytic enzymes with F-actin: effects of poly(ethylene glycol). 333 56

The glycosomes of in vitro grown procyclic trypomastigote forms of Trypanosoma brucei were purified by three different procedures and the results compared by electron microscopy, enzyme assays and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Centrifugation on a self-forming Percoll gradient followed by a sucrose gradient centrifugation resulted in the least enriched glycosomal preparation. Centrifugation on a pre-formed Nycodenz gradient gave an improved preparation but the most homogeneous preparation of intact glycosomes was obtained after centrifugation on two successive sucrose gradients. Glycosomes purified by both the Nycodenz and double sucrose gradient procedures appeared larger than in situ glycosomes presumably due to an osmotic effect resulting from disruption of the granular matrix of the organelles. Nevertheless, there appears to be no loss of cisternal contents due to the swelling of the organelles. The glycosomes of the bloodstream form trypomastigotes purified by the same procedures show, however, no sign of swelling. A comparison of glycosomes purified from procyclic trypomastigotes and bloodstream form trypomastigotes prepared by the same double sucrose procedure demonstrated that in the glycosome of procyclic trypomastigotes: activities of hexokinase, phosphoglucose isomerase, phosphofructose kinase, aldolase and phosphoglycerate kinase and diminished by 80-100%; activities of glyceraldehyde-3-phosphate dehydrogenase, triose phosphate isomerase and glycerol-3-phosphate dehydrogenase remain unchanged or are only slightly reduced; there is an appearance of four major new proteins, among which could be phosphoenol pyruvate carboxykinase and malate dehydrogenase. These observations are in basic agreement with those by Hart et al. (Mol. Biochem. Parasitol. 12, 25-35, 1984).
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PMID:An improved purification of glycosomes from the procyclic trypomastigotes of Trypanosoma brucei. 380 43

Rat liver transketolase (TK) has been purified, in a single step, by immunoaffinity chromatography on specific TK antibodies covalently linked to Sepharose 4B. The procedure described also involves the raising and isolation of rabbit TK antibodies to the conventionally purified enzyme [F. Paoletti (1983) Arch. Biochem. Biophys. 222, 489-496]. Affinity chromatography allows a 100-fold purification of TK from the cell cytosol and a recovery of about 70% of the original activity. The TK isolated has a specific activity of 2.7-3.2 at 25 degrees C and migrates as a single band on polyacrylamide gel electrophoresis at pH 9.1. Multiple forms of the enzyme, with distinct pI values in the range 7-8, have been detected in purified preparations by means of analytical isoelectric focusing and staining for TK. No addition of either Mg2+ or thiamine pyrophosphate is required for the activity of the enzyme which, in the native form, exhibits a molecular weight of about 139,000. Two moles of thiamine pyrophosphate can be resolved for each mole of enzyme. Affinity TK preparations are virtually free of glyceraldehyde-3-phosphate dehydrogenase, pentose-phosphate epimerase, and isomerase, although slight contamination by phosphohexose isomerase may occur.
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PMID:Immunoaffinity purification of rat liver transketolase: evidence for multiple forms of the enzyme. 394 99

Crude extracts of both vegetative cells and glycerol-induced microcysts of Myxococcus xanthus contained the following enzyme activities: phosphofructokinase, phosphoglucoisomerase, fructose-1,6-diphosphatase, fructosediphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, phosphopyruvate carboxylase, citrate synthase, isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, phosphoglucomutase, and uridine diphosphate glucose pyrophosphorylase. With the exception of isocitrate dehydrogenase, which was present at a fivefold higher concentration in microcysts, all activities in extracts from both types of cells were essentially equal. Hexokinase and pyruvate kinase could not be detected in extracts from either type of cell. Microcysts metabolized acetate at a lower rate than did vegetative cells. Most of this decrease was reflected in a substantial decrease in ability of microcysts to oxidize acetate to CO(2). In addition, microcysts and vegetative cells showed a different distribution of (14)C-label from incorporated acetate.
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PMID:Comparative intermediary metabolism of vegetative cells and microcysts of Myxococcus xanthus. 430 96

Red cell enzymes, 2,3-diphosphoglycerate (2,3-DPG) and adenosine triphosphate (ATP), were evaluated in a 23-mo-old boy with juvenile chronic myelocytic leukemia (JCML) at the onset of his illness and 6 mo later during the accelerated phase. The activities of the age-dependent red cell enzymes, hexokinase, aldolase, pyruvate kinase, and glucose-6-phosphate dehydrogenase, were elevated, as were the concentrations of red cell 2,3-DPG and ATP, consistent with a young red cell population metabolizing at an increased glycolytic rate. The activities of the non-age-dependent enzymes, glyceraldehyde-3-phosphate dehydrogenase (G3PD), phosphoglycerate kinase, and enolase, were also increased to levels similar to or greater than those observed in term infants. As the illness progressed, the activity of red cell G3PD increased further, and phosphoglucose isomerase activity increased markedly. These results are consistent with the prior suggestion that JCML represents a reversion to "fetal" erythropoiesis.
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PMID:Fetal erythropoiesis in juvenile chronic myelocytic leukemia. 622 20


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