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)

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

The activities of key enzymes of glycolysis and of the glucose shunt as well as the capacity of lactic acid formation were determined in the high-speed tissue supernatant of the transplantable Albert hepatoma of mouse [originally produced by oral application of chrysoidin (2,4-diaminoazobenzene) on C57 Black mice]. Furthermore, the particle-bound hexokinase activity was determined. The following results were obtained: In the hepatoma the activities of aldolase, pyruvate kinase and lactic dehydrogenase are hardly altered compared with normal liver. The activities of hexokinase and phosphofructokinase are increased 2,5-fold, those of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase 2-fold. The capacity for lactic acid formation from glucose is 7 times as high in the hepatoma supernatant. Strong differences emerge from the liver-to-hepatoma relationship in terms of intracellular distribution of the hexokinase (total homogenate 1 : 5, supernatant 1 : 2,5 and particle-bound hexokinase activity 1 : 18). A summarizing consideration of all the results obtained so far for the Albert hepatoma shows that this malignoma departss in several biochemical parameters from the "Molecular Correlation Concept" maintained by Weber, providing more evidence for the individuality of tumors.
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PMID:[Activities of several enzymes of glycolysis and of the glucose shunt in the Albert hepatoma of mouse (author's transl)]. 625 66

In order to evaluate properly red cell metabolic data obtained in newborns with congenital hemolytic disorders, the unique metabolic characteristics and normal developmental changes that occur prenatally and postnatally are presented. The age-dependent red cell glycolytic enzymes (hexokinase, aldolase, pyruvate kinase) and glucose-6-phosphate dehydrogenase and most glycolytic intermediates are elevated at birth and at 11 to 12 months of age, consistent with the presence of a young red cell population the entire first year of life. However, certain red cell enzymes are elevated out of proportion to the age of the red cell population [phosphoglucose isomerase. glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase (PGK), and enolase (ENO)] whereas others are decreased [phosphofructokinase (PFK), glutathione peroxidase, carbonic anhydrase, and others]. These metabolic characteristics are felt to be unique and representative of "fetal erythropoiesis." Activities of PGK and ENO decrease the PFK increases toward normal adult values beginning at eight to nine weeks of age. The concentration of glucose-6-phosphate steadily increases after birth and peaks at three to four weeks of age, at a time when PFK activity remains relatively unchanged, suggesting a relative block in glycolysis at the PFK step secondary to an enzyme with both decreased activity and altered kinetic properties (a "fetal" isozyme). Thus, evaluation of red cell enzyme and glycolytic intermediate data obtained in the first year of life should be related to the knowledge that a young red cell population is present and the characteristic unique metabolic red cell alterations described in cord blood persist beyond the immediate neonatal period.
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PMID:Red cell enzymopathies in the newborn. I. Evaluation of red cell metabolism. 628 May 78

A marked reduction of granulocyte chemotactic function accompanies the storage of granulocyte concentrates. Since chemotaxis is energy dependent, we studied energy metabolism in stored neutrophils. We and others have reported that stored neutrophils have a defect in their energy metabolism. We found that defective adenosine triphosphate maintenance in stored neutrophils was occult in resting cells, but was unmasked by an energy-intensive stimulus, phagocytosis. In studies reported here, we sought to determine if defective adenosine triphosphate maintenance during granulocyte storage was related to altered glycolytic enzyme activity. We studied the activity of glycolytic enzymes in fresh and stored, resting and stimulated (opsonized zymosan) neutrophils. The following enzyme activities showed no major changes during storage, in resting or stimulated neutrophils: hexokinase, phosphofructokinase, aldolase, glucose phosphate isomerase, triose phosphate isomerase, glyceraldehyde phosphate dehydrogenase, phosphoglycerate kinase, phosphoglyceromutase, enolase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase, glutathione reductase, and glutathione peroxidase. In contrast, pyruvate kinase activity consistently increased during storage. In 6 units, pyruvate kinase activity increased by 75 percent after 24 hours of storage at room temperature and by 198 percent after 48 hours. The storage-associated increase in pyruvate kinase activity was not inhibited by cycloheximide. Stimulation of neutrophils by phagocytosis of opsonized zymosan also produced striking increases in the pyruvate kinase activity of both fresh and stored cells. Additional studies indicated that the increases in pyruvate kinase activity observed during storage and after phagocytosis were associated with an increase in the availability of pyruvate kinase activity in the supernatant fraction of neutrophil sonicates. Total pyruvate kinase activity in sonicates of neutrophils was unchanged by storage or particle ingestion.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Glycolytic enzymes of stored granulocytes. 632 24

Intraperitoneal administration of leupeptin to rats induced a hemoglobin-hydrolyzing protease which was most active at pH 3.5 and was insensitive to pepstatin in various tissues such as the liver, kidney, and muscle, as observed previously in adult rat hepatocytes in primary culture (Tanaka, K., Ikegaki, N., and Ichihara, A. (1979) Biochem. Biophys. Res. Commun. 91, 102-107). The induced acidic protease was purified about 600-fold in 30% yield from rat liver by conventional chromatographic techniques. The purified enzyme appeared homogeneous by polyacrylamide gel electrophoresis in the presence or absence of sodium dodecyl sulfate and was a monomeric protein of Mr = 20,000. The enzyme appeared to be a glycoprotein because its induction was blocked by the addition of tunicamycin to cultures of hepatocytes and because the induced protease was absorbed on concanavalin A-Sepharose and eluted with methylglucoside. It seemed to be present in lysosomes and was fairly stable at various pH values and temperatures. It showed endopeptidase activity on various protein substrates, but scarcely hydrolyzed N-substituted derivatives of arginine. It did not hydrolyze esters, showed no aminopeptidase or carboxypeptidase activity, and did not inactivate glucose-6-phosphate dehydrogenase or aldolase. The enzyme appeared to be a thiol protease, since it was strongly inhibited by sulfhydryl-reactive compounds and N-( [N-(1-3-trans-carboxyoxiran-2-carbonyl)-L-leucyl]-agmatine and was not inhibited by reagents specific for carboxyl-, serine-, or metalloproteases. This induced protease could be separated from cathepsins B, D, and H by chromatography. The enzyme was similar to cathepsin L in chromatographic behavior, Mr and pI, but differed from the latter in stability and in its inability to inactivate some enzymes. These results suggest that it differs from any known proteases found previously in rat liver.
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PMID:Purification and characterization of hemoglobin-hydrolyzing acidic thiol protease induced by leupeptin in rat liver. 637 Oct 12

Glucose may be converted to 6-phosphogluconate by alternate pathways in Pseudomonas aeruginosa. Glucose is phosphorylated to glucose-6-phosphate, which is oxidized to 6-phosphogluconate during anaerobic growth when nitrate is used as respiratory electron acceptor. Mutant cells lacking glucose-6-phosphate dehydrogenase are unable to catabolize glucose under these conditions. The mutant cells utilize glucose as effectively as do wild-type cells in the presence of oxygen; under these conditions, glucose is utilized via direct oxidation to gluconate, which is converted to 6-phosphogluconate. The membrane-associated glucose dehydrogenase activity was not formed during anaerobic growth with glucose. Gluconate, the product of the enzyme, appeared to be the inducer of the gluconate transport system, gluconokinase, and membrane-associated gluconate dehydrogenase. 6-Phosphogluconate is probably the physiological inducer of glucokinase, glucose-6-phosphate dehydrogenase, and the dehydratase and aldolase of the Entner-Doudoroff pathway. Nitrate-linked respiration is required for the anaerobic uptake of glucose and gluconate by independently regulated transport systems in cells grown under denitrifying conditions.
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PMID:Regulation of alternate peripheral pathways of glucose catabolism during aerobic and anaerobic growth of Pseudomonas aeruginosa. 640 87

In myocardial hypertrophy activity of hexokinase was decreased in heart mitochondria and increased in the supernatant obtained after precipitation of the mitochondria. Activities of phosphofructokinase and fructose diphosphate aldolase were decreased within the acute period of hyperfunction and hypertrophy of myocardium. Under these conditions pentosemopophosphate shunt of carbohydrate metabolism was activated as indicated by the increase in glucose-6-phosphate dehydrogenase activity; the enzyme activity was decreased during the period of hypertrophy atabilization. Possible causes of alteration in the activity of the enzymes of carbohydrate metabolism under conditions of heart hypertrophy are discussed.
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PMID:[Enzymatic activity of the glycolytic and pentosemonophosphate pathways of carbohydrate conversion in the heart in hypertrophy]. 644 26

The activities of red cell enzymes enolase (ENO), phosphoglycerate kinase (PGK), phosphofructokinase (PFK), glucose-6-phosphate dehydrogenase (G-6-PD), hexokinase (HK), aldolase (ALD), and pyruvate kinase (PK) were followed sequentially in term infants from birth to one year of age. At birth, red cell PGK and ENO activities were disproportionately elevated when compared to both red cells with a similar mean cell age and those with a younger mean cell age; red cell PFK was significantly decreased. There was a progressive full in PGK and ENO activities and rise in PFK levels toward normal values in the first year of life. The most significant changes in PGK, ENO, and PFK appeared to begin at 8 to 9 wk of age. ENO and PFK activities stabilized at approximately 5 to 6 months of age at values compatible with mean cell age; mean PGK levels remained mildly elevated at 11 to 12 months. The age-dependent enzymes G-6-PD, PK, ALD, and HK were all elevated in term newborns. G-6-PD and ALD progressively decreased in activity during the first year of life. PK and HK decreased in activity until 8 to 9 wk when there was a secondary rise in mean activity. Mean red cell G-6-PD, PK, ALD, and HK levels remained mildly to moderately elevated at 11 to 12 months of life, suggesting the persistence of a relatively young red cell population throughout the first year of life.
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PMID:Red cell metabolic alterations in postnatal life in term infants: glycolytic enzymes and glucose-6-phosphate dehydrogenase. 645 61

Bilipolinum (Adipiodon), iodine contrast medium used in cholangiography, showed an inhibitory effect on the activity of human erythrocyte phosphohexoseisomerase, phosphofructokinase, aldolase and glucose-6-phosphate dehydrogenase. The addition of glucose metabolites (glucose-6-phosphate, fructose-6-phosphate, fructose-1,6-bis-phosphate, pyruvate and lactate) abolished the inhibitory effect of Bilipolinum. In the presence of Bilipolinum purified erythrocyte phosphofructokinase showed a decreased affinity towards substrate, modified allosteric properties and reduced stability at pH below 7.5. Purified erythrocyte glucose-6-phosphate dehydrogenase was also affected by Bilipolinum and its affinity for NADP was decreased. Testing of erythrocyte enzymes in the evaluation of toxicity of iodine contrast media is discussed.
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PMID:The effect of bilipolinum (Adipiodon), an iodine contrast medium on erythrocyte enzymes. 645 4

Late committed progenitor cells of erythropoiesis, CFU-E (colony-forming unit--erythroid), were isolated from mouse spleens to near homogeneity by a three-step enrichment procedure. The procedure included a four-day pretreatment of bled mice with the antibiotic thiamphenicol, a recovery period of 3 1/2 days, followed by centrifugal elutriation and Percoll density gradient centrifugation of the spleen cells. This practically pure CFU-E population was used to study some aspects of erythroid differentiation in vitro. Colony growth, as well as morphology and glycolytic enzyme activities of cells isolated at selected times of the 48-hour culture period, were determined. Marked declining activities of several enzymes, including hexokinase, phosphofructokinase, aldolase, enolase, pyruvate kinase, and glucose-6-phosphate dehydrogenase, were observed during in vitro differentiation. The activity of diphosphoglycerate mutase was almost absent in the CFU-E, but progressively increased during differentiation. The isozyme distribution of aldolase and enolase did not change during CFU-E in vitro differentiation into the reticulocyte. Hexokinase (HK) in the CFU-E contained mainly a double-banded type I isozyme, in addition to a minor amount of HK II. During differentiation, a shift was noticed within the double-banded HK I region, whereas HK ii disappeared after one cell division. Pyruvate kinase in the CFU-E was characterized by the presence of both the K-type and the L-type isozyme and hybrids of these isozyme types. During in vitro differentiation, the production of the K-type isozyme rapidly stops in favor of the L type.
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PMID:Changes in activities and isozyme patterns of glycolytic enzymes during erythroid differentiation in vitro. 646 70


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