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)

Clostridium thermocellum was shown to ferment glucose in a medium containing salts and 0.5% yeast extract. An active glucokinase was obtained with improved conditions for growth, assay, and preparation of cell extracts. Cell extracts appear to contain a glucokinase inhibitor that interferes with the assays at high protein concentrations. Glucokinase activity is stimulated about 60% by pretreatment with dithiothreitol. Little or no fructokinase or mannokinase activity was detected in cell extracts. The absence of glucokinase in mannitol-grown cells, the increase in glucokinase activity upon incubation of cell suspensions with glucose, and the lack of increase in activity when chloramphenical is added are evidence that glucokinase is an inducible enzyme. The following enzymes were detected in cell extracts (the enzyme activities are shown in parentheses are micromoles per minute per milligram or protein at 27 C): glucokinase (0.48), phosphoglucose isomerase (0.73), fructose 6-phosphate kinase (0.24), fructose diphosphate aldolase (0.59), glyceraldehyde 3-phosphate dehydrogenase (0.53), triose phosphate isomerase (0.13), phosphoglycerate kinase (0.20), phosphoglycerate mutase (0.20), enolase (0.28), pyruvic kinase (0.13), and lactic dehydrogenase (0.13). Glucose 6-phosphate dehydrogenase activity was absent or very low (0.0002) and 6-phosphogluconate dehydrogenase activity also was relatively low (0.015). From these data, it is proposed that carbohydrate metabolism in C. thermocellum proceeds by the Embden-Meyerhof pathway.
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PMID:Utilization of glucose by Clostridium thermocellum: presence of glucokinase and other glycolytic enzymes in cell extracts. 554 Oct 8

Some highly purified glycolytic enzymes have been subjected to isoelectric focusing and found to contain a number of enzymatically active species. Crystalline aldolase A and glyceraldehyde-3-phosphate dehydrogenase from rabbit muscle were resolved into five components, crystalline aldolase from yeast was resolved into three components, pyruvate kinase from rabbit muscle yielded four components, and yeast enolase was resolved into two components. Rabbit muscle lactate dehydrogenase (M(4)) gave one major peak of protein and enzymatic activity. The profiles of aldolase, glyceraldehyde-3-phosphate dehydrogenase, and yeast aldolases suggest random combinations of two closely related subunits into tetramers and dimers, respectively. The molecular heterogeneity of the other enzymes is not so easily related to subunit structure.
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PMID:Heterogeneity of presumably homogeneous protein preparations. 580 37

Enzymes of the reductive pentose phosphate cycle including ribulose-diphosphate carboxylase, ribulose-5-phosphate kinase, ribose-5-phosphate isomerase, aldolase, glyceraldehyde-3-phosphate dehydrogenase and alkaline fructose-1,6-diphos-phatase were shown to be present in autotrophically grown Rhodospirillum rubrum. Enzyme levels were measured in this organism grown photo- and dark heterotrophically as well. Several, but not all, of these enzymes appeared to be under metabolic control, mediated by exogenous carbon and nitrogen compounds. Light had no effect on the presence or levels of any of these enzymes in this photosynthetic bacterium. The enzymes of the tricarboxylic acid cycle and enolase were shown to be present in R. rubrum cultured aerobically, autotrophically, or photoheterotrophically, both in cultures evolving hydrogen and under conditions where hydrogen evolution is not observed. Light had no clearly demonstrable effect on the presence or levels of any of these enzymes.
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PMID:Photosynthesis in Rhodospirillum rubrum. 3. Metabolic control of reductive pentose phosphate and tricarboxylic acid cycle enzymes. 604 59

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

A study has been made of the effects of phytohaemagglutinin on the gene expression of the glycolytic enzymes in cultured human lymphocytes. All the enzymes were found to show an average increase in activity of between 160% and 360% in stimulated cells, but the increases were greater for the enzymes comprising the second half of the pathway. The enzyme activities in stimulated cells, cultured for 72 h, were similar to the activities measured in long-term lymphoid lines. Starch-gel electrophoresis was used to examine the isozyme patterns of the enzymes before and after exposure of the lymphocytes to PHA. Six of the enzymes showed isozyme patterns unchanged by stimulation. Four of the enzymes, aldolase, triosephosphate isomerase, enolase and lactate dehydrogenase, showed different isozyme patterns in stimulated cells from those seen in uncultured or unstimulated cells. The electrophoretic results showed a good correlation in isozyme pattern between uncultured lymphocytes and cultured unstimulated lymphocytes, and between PHA-stimulated lymphocytes and long-term lymphoid lines.
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PMID:Changes in the activity and isozyme patterns of glycolytic enzymes during stimulation of normal human lymphocytes with phytohaemagglutinin. 624 69

The present work describes procedures in which seven major muscle enzymes and serum albumin can be simultaneously isolated from chicken skeletal muscles. The seven enzymes isolated were: phosphorylase, enolase, creatine-P kinase, aldolase, glyceraldehyde-3-P dehydrogenase, phosphoglycerate mutase, and triose-P isomerase. The proteins isolated by these methods were judged to be greater than 97% pure on the basis of electrophoretic analysis in sodium dodecyl sulfate polyacrylamide gels. The procedure is applicable for isolation of the enzymes from large (greater than 100 g) or small (less than 0.5 g) amounts of muscle tissue and the entire procedure can be completed within two days. Particularly useful features of the procedures are: (1) preferential solubilization of the enzymes from myofibrils by extraction of muscle specimens in solutions of different ionic strength; (2) specific precipitation of phosphorylase, creatine-P kinase, and glyceraldehyde 3-Phosphate dehydrogenase from solutions of specified pH and degrees of ammonium sulfate saturation; and (3) an alternate method for isolation of glyceraldehyde-3-P dehydrogenase by specific elution of the enzyme from phosphocellulose columns with ATP. Because of the ease, rapidity, and reproducibility of the procedures, these methods may be useful for the routine isolation of the muscle enzymes in studies on biochemical regulation, as well as for obtaining large quantitites of the enzymes for structural analysis.
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PMID:A simple procedure for the isolation of seven abundant muscle enzymes. 626 Dec 32

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

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

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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