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)

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

Six mutants lacking the glycolytic enzyme fructose 1,6-bisphosphate aldolase have been isolated in the yeast Saccharomyces cerevisiae by inositol starvation. The mutants grown on gluconeogenic substrates, such as glycerol or alcohol, and show growth inhibition by glucose and related sugars. The mutations are recessive, segregate as one gene in crosses, and fall in a single complementation group. All of the mutants synthesize an antigen cross-reacting to the antibody raised against yeast aldolase. The aldolase activity in various mutant alleles measured as fructose 1,6-bisphosphate cleavage is between 1 to 2% and as condensation of triose phosphates to fructose 1,6-bisphosphate is 2 to 5% that of the wild-type. The mutants accumulate fructose 1,6-bisphosphate from glucose during glycolysis and dihydroxyacetone phosphate during gluconeogenesis. This suggests that the aldolase activity is absent in vivo.
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PMID:Saccharomyces cerevisiae aldolase mutants. 638 92

Lymph-node cells of (AKR X C3H) F1 leukaemic mice showed a considerable increase of glycolytic activity and O2 consumption. The glycolytic enzymes phosphofructokinase, pyruvate kinase, aldolase and lactic acid dehydrogenase showed increased activities in leukaemic conditions. Studies on permeabilized leukaemic and normal lymph-node cells, and assays on partially purified phosphofructokinase and pyruvate kinase enzymes, revealed that the enhanced glycolysis of the tumour cells was due to the predominance of glycolytic isoenzymes relatively insensitive to the natural metabolic inhibitors. The glycolytic enzyme hexokinase showed decreased activity in leukaemic conditions, owing to a subcellular translocation of its bulk from the cytosol to the mitochondrial fraction. Association of hexokinase with the mitochondria accounted for an ATPase-like stimulatory action on cell respiration which can explain the increased O2 uptake of leukaemic cells.
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PMID:Regulation of glycolysis and oxygen consumption in lymph-node cells of normal and leukaemic mice. 645 31

The nature of the association of the glycolytic enzyme, aldolase, with mature bovine spermatozoa was investigated in comparison with bovine muscle aldolase. Bovine muscle aldolase (BMA) was optimally solubilized by 0.1% deoxycholate and purified to homogeneity by ammonium sulfate fractionation, gel-filtration chromatography and phosphocellulose affinity chromatography. Bovine sperm aldolase (BSpA) was solubilized with optimal specific activity by 0.1% Triton X-100 and 50 mM sodium phosphate. Soluble BSpA represented 10% of the total aldolase activity in bovine spermatozoa. It could not be purified from other sperm components by standard procedures. The association of BSpA with sperm components involved noncovalent, ionic and hydrophobic interactions and did not involve disulfide bonds or covalent bonds. The stability of the BSpA association with intracellular substructure implies that very specific multiple-ligand bonding is involved. The Km for fructose-1-phosphate (1.7 X 10(-1) M) was higher and the activity with fructose-1,6-biphosphate relative to fructose-1-phosphate (Vmax FBP/Vmax F-1-P = 0.038) was much lower than for either liver or muscle aldolase. Kinetic analysis and subcellular associations indicated that sperm aldolase is different from other isozymes of aldolase.
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PMID:Association of bovine sperm aldolase with sperm subcellular components. 646 57

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

Isozyme patterns of 23 different enzymes were compared in normal, benign, and malignant breast tissues; in MCF-7 cells; and in organoids of normal human breast tissue. Benign lesions generally showed isozyme patterns similar to those of normal tissues. Lactate dehydrogenase isozyme 5 was significantly increased in malignant tumors; MCF-7 cells had only lactate dehydrogenase (L-lactate:NAD oxidoreductase; EC 1.1.1.27). The mitochondrial form of malate dehydrogenase was also significantly increased in human malignant tumors; this was especially evident when comparing tumor and apparently uninvolved breast tissue from the same patient. The K4 isozyme of pyruvate kinase was the major form in most malignant breast tumors, but in only 41% of normal tissues, 30% of fibrocystic disease specimens, and 46% of fibroadenomas. A more anodal band of pyruvate kinase, probably a K3M or K3Kpm hybrid, predominated in most normal and benign tissues, but in only 63% of primary and 56% of secondary tumors. All specimens had predominantly creatine kinase BB, aldolase A4, and hexokinase I. Traces of aldolase A3C and of hexokinase II were observed in some tumors. None of the tumors had the Regan variant of alkaline phosphatase. The isozymes of lactate and malate dehydrogenases and of pyruvate kinase appear to be the most promising as putative tumor markers.
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PMID:Isozyme patterns of normal, benign, and malignant human breast tissues. 664 May 38

Perfused rat hearts show a markedly increased binding of phosphofructokinase and fructose-bisphosphate aldolase as a consequence of ischaemia, but little change in binding of pyruvate kinase, lactate dehydrogenase or glyceraldehyde-3-phosphate dehydrogenase. After 10 min ischaemia over one quarter of the phosphofructokinase and three quarters of the aldolase are bound. The effect of anoxia is less well marked in its influence on binding with only aldolase showing a significant increase in binding. These results suggest that one factor involved in the increased binding during ischaemia is the fall in pH of the heart. Binding studies with isolated myofibrils confirm that the affinity and stoichiometry of aldolase binding are considerably increased as the pH is lowered over a range comparable to that which occurs in ischaemic heart. The low level of binding of glyceraldehyde-3-phosphate dehydrogenase in perfused rat hearts correlates with the relatively low affinity of this enzyme for binding to rat or rabbit cardiac myofibrils. There are species differences in the enzyme binding response to ischaemia. Sheep hearts show rapid and large increases in the binding of glyceraldehyde-3-phosphate dehydrogenase in addition to changes in aldolase and phosphofructokinase binding. The greater binding of glyceraldehyde-3-phosphate dehydrogenase reflects the greater affinity of sheep cardiac myofibrils. It is suggested that the altered metabolic demands of ischaemia are satisfied by changes in glycolytic enzyme organisation as the enzymes shift from the soluble to the particulate phase of cardiac muscle.
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PMID:Metabolic dependence of glycolytic enzyme binding in rat and sheep heart. 669 39

The development of key enzyme activities concerned with glucose metabolism was studied in six regions of the rat brain in animals from just before birth (-2 days) through the neonatal and suckling period until adulthood (60 days old). The brain regions studied were the cerebellum, medulla oblongata and pons, hypothalamus, striatum, mid-brain and cortex. The enzymes whose developmental patterns were investigated were hexokinase (EC 2.7.1.1), aldolase (EC 4.1.2.13), lactate dehydrogenase (EC 1.1.1.27) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49). Hexokinase, aldolase and lactate dehydrogenase activities develop as a single cluster in all the regions studied, although the timing of this development varies from region to region. Glucose-6-phosphate dehydrogenase activity, however, declines relative to glycolytic enzyme activity as the brain matures. When the different brain regions are compared, it is clear that the medulla develops its glycolytic potential, as indicated by its potential enzyme activity, considerably earlier than the other regions (hypothalamus, striatum and mid-brain), with the cortex and cerebellar activities developing even later. This enzyme developmental sequence correlates well with the neurophylogenetic development of the brain and adds support to the hypothesis that the development of the potential for glycolysis in the brain is a necessary prerequisite for the development of neurological competence.
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PMID:Regional enzyme development in rat brain. Enzymes associated with glucose utilization. 671 9

Ingestion rate of granulocytes in osteomyelofibrosis with splenomegaly, which is still a matter of controversy, was measured in 32 patients. The mean ingestion rate in patients' granulocytes was similar to that of the controls; the results, however, were more dispersed in the patients than in the controls, with very high (three patients) and very low (three patients) ingestion rates. Ingestion alterations were serum-independent. Neutrophil glycolytic enzymes and adenylate-kinase were measured in order to assess: (1) if they could be responsible for the observed abnormalities and (2) if enzyme abnormalities, previously described in red blood cells, also occur in the neutrophils. Major increases in phosphofructoaldolase and in 3-phosphoglycerate kinase activities, contrasting with a decrease in pyruvate kinase activity were observed. These, however, did not correlate with ingestion alterations. In conclusion, we showed that the granulocyte ingestion rate is altered in a few patients only, that the alterations are unrelated to the serum, to adenylate kinase or to glycolytic enzyme abnormalities. The latter, however, are important. The mechanisms of their occurrence are unknown and hypotheses such as those proposed for red blood cells enzyme modifications in myeloproliferative disorders could be applicable.
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PMID:Ingestion rate and glycolytic enzymes in neutrophils of patients with agnogenic osteomyelofibrosis and splenomegaly. 671 65

Purified glycolytic enzymes were individually chromatographed through columns of Sepharose 4B containing a covalently bound F-actin-tropomyosin complex. Five of these enzymes, aldolase, glyceraldehyde-phosphate dehydrogenase, lactate dehydrogenase, pyruvate kinase, and phosphoglycerate kinase were able to interact with the complex. Glucosephosphate isomerase, triosephosphate isomerase, phosphoglycerate phosphomutase, and enolase did not bind to the F-actin-tropomyosin matrix. One nonbinding enzyme, phosphoglycerate phosphomutase, was observed to interact with F-actin-tropomyosin if the column was preloaded with lactate dehydrogenase. Since at least four other glycolytic enzymes did not associate with actin directly, it is suggested that if a glycolytic enzyme complex exists, these nonadsorbing enzymes must interact with one or more of the enzymes which do bind to actin.
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PMID:Interaction of muscle glycolytic enzymes with thin filament proteins. 729 40


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