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)

1. Activities of trout liver glucose dehydrogenase (GDH, EC 1.1.1.47) and glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49) were increased after a sudden drop in water temperature, but not in long-time cold acclimated as compared with warm acclimated trout. 2. Possibly, the activities of GDH and G6PD were temporarily increased in connection with metabolic adaptation to the lower temperature. 3. The activities of GDH and G6PD were not changed by the stress of handling. 4. Partially purified trout liver GDH has a lower activation energy with glucose than with glucose-6-phosphate as substrate, and the Km (glucose) decreases with decreasing assay temperature. 5. At low temperatures, the activity of trout liver GDH with glucose as substrate may be comparable to that of glucose-6-phosphate. 6. Partially purified beef liver GDH has a high activation energy with glucose as substrate, and the Km (glucose) does not change with the assay temperature. 7. Hexokinase (HK, EC 2.7.1.1) and GDH activities were unchanged when trout were deprived of food for 4 weeks. Apparently, the trout liver glucose utilization did not adapt to the starvation.
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PMID:Glucose dehydrogenase, glucose-6-phosphate dehydrogenase and hexokinase in liver of rainbow trout (Salmo gairdneri). Effects of starvation and temperature variations. 176 17

Interpretation of enzymatic data requires consideration of the food intake of each animal studied. Food intake and body mass gain are closely correlated in rapidly growing animals. Direct measurement of food intake by individual fish within a school is nearly impossible. We examined the relationship between growth and liver enzyme activity as a means of inferring the food intake of individual fish within a school. Trout, identified by passive integrated transponder implants, were fed either 0, 0.3, 1, or 2% body mass/d to produce a wide range of growth rates. The activities of five enzymes, predominantly localized in liver, were measured. Results showed that, although the magnitude of response differed, increases in total liver activities of all five enzymes measured were linearly related to growth. Hexokinase (EC 2.7.1.1) increased at a rate below, and beta-D-glucose:NAD(P)+1-oxidoreductase (EC 1.1.1.47) increased at a rate equivalent to, observed increases in total liver mass. Malic enzyme (EC 1.1.1.40), glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (EC 1.1.1.44) showed preferential increases in activity as food intake increased. Correlation of enzyme activities measured in fish fed restricted rations with either growth or nominal feeding rate showed that growth of individual fish was more closely related to liver enzyme activities than nominal feeding rate.
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PMID:Relationship between growth and selected liver enzyme activities of individual rainbow trout. 205 Dec 29

In order to investigate contributions by glucose metabolism via the Embden-Meyerhof pathway and that via the direct oxidation route to gluconate to initial ATP production during spore germination, respiratory activity and RNA synthesis were compared between the mutant lacking hexokinase and the parent spores of Bacillus megaterium QM B1551. We found that time courses of those metabolic events were almost identical between those spores, thus clearly indicating that NADH formed by a spore-specific enzyme glucose dehydrogenase (EC 1.1.1.47) is solely responsible for aerobic production of ATP at this stage.
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PMID:Glucose metabolism via the Embden-Meyerhof pathway is not involved in ATP production during spore germination of bacillus megaterium QM B1551. A study with a mutant lacking hexokinase. 245 May 41

An improved method has been developed for the assay of hexokinase (EC 2.7.1.1) levels in human tissue homogenates. The enzyme is quantitated by the spectrophotometric measurement, at 340 nm, of NADPH formed according to the reaction scheme: [formula: see text] In tissue homogenates a number of enzymes are present which can interfere with the assay by reacting with substrates or products of the assay reactions. In the described procedure hexokinase is assayed directly in homogenates under conditions in which the effect of possible contaminating enzymes (glucose dehydrogenase, EC 1.1.1.47; glucose 6-phosphatase, EC 3.1.3.9; glucose phosphate isomerase, EC 5.3.1.9; 6-phosphogluconate dehydrogenase EC 1.1.1.44; and NADP-reducing enzymes) are eliminated. Precision studies on the assay gave within-day reproducibility of 4.3% (CV) on a tissue having a mean activity of 1.68 U/g of tissue, and day-to-day variability of 15% (CV) for a tissue averaging 1.83 U/g of tissue.
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PMID:An improved assay for hexokinase activity in human tissue homogenates. 976 31