Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.1.1 (hexokinase)
 5,274 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

By combining field and experimental investigations, we were able to study several new aspects of fundamental problems concerning human and animal schistosomiasis in Senegal. Because of the controversy about the identity of Schistosoma curassoni and the possibly connected zoonosis, this parasite has been described once more. A great variety of experimental techniques were used. The eggs of S. curassoni are significantly smaller than those of the two other African species of Schistosoma we know of in ruminants (S. bovis and S. mattheei). But eggs of S. curassoni cannot be distinguished from those of the human, pathogenic S. haematobium. The study of the tegument of adult male worms shows a clear difference between S. bovis on one hand, and S. curassoni and S. haematobium on the other hand. S. bovis' tubercles are well formed, but have no stings at all. The tubercles of S. haematobium and of S. curassoni definitely possess stings. S. curassoni, S. haematobium and S. bovis are also clearly different as to their development in hamsters (Mesocricetus auratus). S. curassoni develops more rapidly and gets bigger than S. bovis and S. haematobium. Finally, different enzymatic systems allow us to distinguish S. curassoni from other schistosoma's of the haematobium group. S. curassoni has a typical pattern for phosphoglucomutase and hexokinase, differing from S. haematobium's patterns. In S. bovis, it differs by the patterns of phosphoglucomutase, glucosephosphate-isomerase, hexokinase and acid phosphatase. Epidemiological studies proved that, in Senegal, Bulinus guernei is the main vector of S. bovis, Bulinus senegalensis of S. haematobium (Northern Senegal) and Bulinus umbilicatus of S. curassoni and S. haematobium (Southern Senegal). There is no indication to consider S. curassoni as a zoonosis. When ruminants are infested by S. curassoni, the symptoms are light and the most important lesions can be found in the liver, the intestines and, in a lesser degree, in the bladder. S. curassoni develops easily in laboratory animals, giving severe lesions in liver and bowels. That makes it an interesting new model for studying the pathogenesis of schistosomes of the haematobium group and the action of new anthelmintics to be used against them.
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PMID:[Schistosoma species in Senegal with special reference to the biology, epidemiology and pathology of Schistosoma curassoni Brumpt, 1931]. 219 9

Isoenzyme patterns of adult Malaysian Schistosoma, S. mekongi and S. japonicum strains were analysed by isoelectric focusing (IEF) in polyacrylamide gel. Enzyme patterns obtained from Malaysian Schistosoma homogenates differed from those of S. mekongi and S. japonicum strains. Malaysian Schistosoma was found to differ from S. japonicum by 8 enzymes, namely phosphoglucomutase, phosphoglucoisomerase, malate dehydrogenase, acid phosphatase, hydroxy-butyrate dehydrogenase, hexokinase and alkaline phosphatase, and from S. mekongi by phosphoglucomutase, malate dehydrogenase, aldolase and alkaline phosphatase. These results and the distinct biology of the parasite suggest that Malaysian Schistosoma is a new species in the S. japonicum complex.
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PMID:Isoenzyme analyses of Malaysian Schistosoma, S. mekongi and S. japonicum by isoelectric focusing in polyacrylamide gel. 294 Jun 88

1. Rates of insulin secretion, glucose utilization, lactate output, incorporation of glucose into glycogen, contents of glucose 6-phosphate, fructose 1,6-diphosphate and ATP, and maximally extractable enzyme activities of hexokinase, high-K(m) glucose-phosphorylating activity (;glucokinase'), glucose 6-phosphatase and unspecific acid phosphatase were measured in isolated pancreatic islets from fed and 48-h-starved mice. 2. In the fed state insulin secretion from isolated islets was increased five- to six-fold when the extracellular glucose concentration was raised from 2.5mm to 16.7mm; 5mm-caffeine potentiated this effect. The secretory response to glucose of islets from mice starved for 48h was diminished at all glucose concentrations from 2.5mm up to approx. 40mm. Very high glucose concentrations (60mm and above) restored the secretory response to that found in the fed state, suggesting that the K(m) value for the overall secretory process had been increased (approx. fourfold) by starvation. Addition of 5mm-caffeine to islets from starved mice also restored the insulin secretory response to 2.5-16.7mm-glucose to normal values. 3. Extractable hexokinase, ;glucokinase', glucose 6-phosphatase and unspecific phosphatase activities were not changed by starvation. 4. Glucose utilization and glycolysis (measured as the rate of formation of (3)H(2)O from [5-(3)H]glucose over a 2h period) was decreased in islets from starved mice at all glucose concentrations up to approx. 55mm. At still higher glucose concentrations up to approx. 100mm, there was no difference between the fed and starved state, suggesting that the K(m) value for the rate-limiting glucose phosphorylation had been increased (approx. twofold) by starvation. Preparation of islets omitting substrates (glucose, pyruvate, fumarate and glutamate) from the medium during collagenase treatment lowered the glucose utilization measured subsequently at 16.7mm-glucose by 38 and 30% in islets from fed and starved mice respectively. Also the 2h lactate output by the islets at 16.7mm extracellular glucose was diminished by starvation. Incorporation of glucose into glycogen was extremely low, but the rate of incorporation was more than doubled by starvation. 5. After incubation for 30min at 16.7mm-glucose the content of glucose 6-phosphate was unchanged by starvation, that of ATP was increased and the concentration of (fructose 1,6-diphosphate plus triose phosphates) was decreased. 6. Possible mechanisms behind the correlated impairment in insulin secretion and islet glucose metabolism during starvation are discussed.
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PMID:The effect of starvation on insulin secretion and glucose metabolism in mouse pancreatic islets. 415 24

1. The action of beryllium on the following enzymes has been examined: alkaline phosphatase (Escherichia coli and kidney), acid phosphatase, phosphoprotein phosphatase, apyrase (potato), adenosine triphosphatase (liver nuclei, liver mitochondria, brain microsomes), glucose 6-phosphatase, polysaccharide phosphorylases a and b, phosphoglucomutase, hexokinase, phosphoglyceromutase, ribonuclease, A-esterase (rabbit serum), cholinesterase (horse serum), chymotrypsin. Alkaline phosphatase and phosphoglucomutase are inhibited by 1mum-beryllium sulphate whereas the other enzymes are largely unaffected by 1mm-beryllium sulphate. 2. Possible mechanisms for the inhibition of phosphoglucomutase and alkaline phosphatase are discussed.
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PMID:The inhibition of enzymes by beryllium. 428 87

Deciliation of Paramecium tetraurelia by a Ca2+ shock procedure releases a discrete set of proteins which represent about 1% of the total cell protein. Marker enzymes for cytoplasm (hexokinase), endoplasmic reticulum (glucose-6-phosphatase), peroxisomes (catalase), and lysosomes (acid phosphatase) were not released by this treatment. Among the proteins selectively released is a Ca2+-dependent ATPase. This enzyme has a broad substrate specificity which includes GTP, ATP, and UTP, and it can be activated by Ca2+, Sr2+, or Ba2+, but not by Mg2+ or by monovalent cations. The crude enzyme has a specific activity of 2-3 mumol/min per mg; the optimal pH for activity is 7.5. ATPase, GTPase, and UTPase all reside in the same protein, which is inhibited by ruthenium red, is irreversibly denatured at 50 degrees C, and which has a sedimentation coefficient of 8-10 S. This enzyme is compared with other surface-derived ATPases of ciliated protozoans, and its possible roles are discussed.
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PMID:A Ca2+-activated ATPase specifically released by Ca2+ shock from Paramecium tetraurelia. 612 13

The accumulations by axoplasmic transport of selected enzyme activities proximal and distal to a ligature placed on the sciatic nerve were monitored in rats exposed in utero to maternal antibodies to nerve growth factor (NGF) and in control rats. Littermates of the animals exposed to anti-NGF were shown elsewhere to have had a 70% reduction in the number of sensory neurons in dorsal root ganglia and a 90% reduction in number of neurons in superior cervical (sympathetic) ganglion. The accumulation of F(-)-sensitive acid phosphatase activity was depressed 75% both proximal and distal to the tie. Accumulation of F(-)-resistant acid phosphatase activity was depressed nearly 50% proximal to the tie. Distal accumulation of this activity did not occur in either group of rats. Accumulation of acetylcholinesterase activity was depressed 30%. Distal accumulation of the activities of beta-glucuronidase and hexokinase was depressed 50%. In the lumbar dorsal root ganglia, dry weight was reduced 40%, and the activities of peroxide-sensitive, F(-)-resistant acid phosphatase and of the mitochondrial enzymes hexokinase, glutamic dehydrogenase, glutamic-oxalacetic transaminase, and NAD-dependent isocitric dehydrogenase were all reduced a little more, 45--50% per ganglion. However, the activities of the lysosomal enzymes, F(-)-sensitive acid phosphatase and beta-glucuronidase, of the peroxide-resistant, F(-)-resistant acid phosphatase, and of the mitochondrial enzyme glutaminase were all reduced about 60% per ganglion. The results of these measurements were interpreted to suggest that much, and perhaps all, of the F(-)-sensitive acid phosphatase activity in motion in peripheral nerve in rat is confined to sensory axons.
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PMID:Transported enzymes in sciatic nerve and sensory ganglia of rats exposed to maternal antibodies against nerve growth factor. 616 7

Leishmania mexicana mexicana amastigotes have been shown to contain greater activities than promastigotes of the enzymes that catalyse the beta-oxidation of fatty acids, but lower activities of several glycolytic enzymes, with the activity of pyruvate kinase being especially low. The results suggest the beta-oxidation of fatty acids is relatively more important to Leishmania amastigotes than promastigotes, whereas the reverse is true for glycolysis. Succinic dehydrogenase and peptidase activities were much higher in promastigotes than amastigotes. The activities of glucose-6-phosphatase, fructose-1,6-bisphosphatase, acid phosphatase and glucose-6-phosphate dehydrogenase varied less, although in each case the activity was significantly lower in the mammalian stage. A method for lysing and fractionating L. m. mexicana promastigotes has been developed. Using this procedure it has been established that many of the glycolytic and functionally related enzymes are located in cell organelles, that hexokinase is intimately connected with the particulate part of the parasite, and that the microsomal fraction of L. m. mexicana is very different in composition from the microsomes of mammalian liver cells.
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PMID:A comparative study of Leishmania mexicana amastigotes and promastigotes. Enzyme activities and subcellular locations. 621 17

Muscle hypertrophy was induced in the soleus muscle of young rats by tenotomy of the gastrocnemius and plantaris muscles. Three and 7 days afterwards the sciatic nerve was sectioned. The loss of weight of muscles subjected to this combined procedure three days after denervation was 30-40%. Lysosomal enzyme activities (acid phosphatase, alpha-glucosidase, beta-galactosidase and N-acetyl-beta-D-glucosaminidase) and energy enzyme activities (lactate dehydrogenase, LDH, triose-3-phosphate dehydrogenase, TPDH , D-hexokinase, HK and citrate synthase, CS) were determined 3 days after denervation, 3, 7 and 10 days after hypertrophy had been induced and 3 days after denervation of hypertrophying muscles on day 3 and 7. Normal non-operated rats of corresponding body weight served as controls and their enzyme activities were estimated on the same day. In the course of muscle hypertrophy, the 4 lysosomal enzyme activities increased progressively. Although 3 days' denervation of control muscles did not alter lysosomal enzyme activities, denervation of hypertrophying muscles greatly enhanced the activity of these enzymes. Enzymes of energy metabolism were affected to a lesser degree. The results suggest that denervation of hypertrophying muscles causes more extreme changes in muscle weight and lysosomal enzyme activities than denervation alone. The possible implications of this finding are discussed in relation to the rapid atrophy.
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PMID:Lysosomal and energy enzyme activities in hypertrophied rat soleus muscle after denervation. 671 25

The eggs of Schistosoma bovis isolated from Misungwi, Tanzania measure 211.1 micrometer +/- 18.4 long and 66.7 micrometer +/- 5.4 wide. The parasite is naturally transmitted by Bulinus africanus and is compatible in the laboratory with snails belonging to the B. truncatus. B. forskali, and B. reticulatus groups. The compatibility with B. africanus group snails is shared with isolates from Kenya and Sudan but not with S. bovis from more northern distributions. Enzyme analyses were carried out by isoelectric focusing. In adult worms, phosphoglucomutase (PGM), hexokinase (HK), malate dehydrogenase (MDH), and lactate dehydrogenase (LDH) proved to be monomorphic whereas two types of glucosephosphate isomerase (GPI), three types of glucose-6-phosphate dehydrogenase (G6PDH), and two types of acid phosphatase (AcP) were identified. Differences in the pI values of gPI and MDH of snail digestive glands and of larval parasites allowed the intramolluscan stages to be characterised. The GPI heterogeneity encountered was common both to the larval and adult parasites. The enzyme types identified in S. bovis are discussed both from an intra- and interspecific viewpoint.
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PMID:Observations on an isolate of Schistosoma bovis from Tanzania. 743 72

Schizosaccharomyces pombe was treated with either cycloheximide or anisomycin at levels sufficient to inhibit > 95% of protein synthesis for periods upon to 3 h, equivalent to one cell cycle. Treatment for as little as 1 h caused significant loss of the Golgi apparatus by both immunofluorescence and electron microscopy. The loss was quantitated by stereology on electron micrographs. Nearly 90% of the stacked Golgi was lost over a 3 h period. No other intracellular membrane compartment seemed to be affected. Measurement of enzyme activities confirmed these observations. The activity of a resident of the Golgi apparatus, alpha-1,2 galactosyltransferase, was reduced over this time, whereas the endoplasmic reticulum marker, BiP, and the cytoplasmic enzyme, hexokinase, were unaffected. The morphological changes associated with cycloheximide addition were reversed on its removal, though there was a lag before cells recommenced growth or secretion of the enzyme, acid phosphatase.
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PMID:Inhibition of protein synthesis disrupts the Golgi apparatus in the fission yeast, Schizosaccharomyces pombe. 820 44


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