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    Hydroxysteroid Dehydrogenases
    Hydroxysteroid Dehydrogenases
    Hydroxysteroid
    White (mutation)
    Citations (3)
    After cultivation of Streptomyces hydrogenans in the presence of different steroids the activity of both 3 alpha, 20 beta-hydroxysteroid dehydrogenase and 3 beta, 17 beta-hydroxysteroid dehydrogenase was determined in the cell homogenate of the microorganism. By comparing the efficacy of the steroids to increase enzyme activities, steroids could be divided into 3 groups: a) steroids which stimulated preferentially the activity of 3 alpha, 20 beta-hydroxysteroid dehydrogenase (e. g., corticosterone), b) steroids which stimulated preferentially 3 beta, 17 beta-hydroxysteroid dehydrogenase (estradiol-17 beta), and c) those behaving intermediately (e. g., progesterone, 5 alpha -dihydrotestosterone). Highest 3 beta, 17 beta-hydroxysteroid dehydrogenase activity could be measured 2 h after addition of 5 alpha-dihydrotestosterone to the culture medium. The activity of 3 alpha, 20 beta-hydroxysteroid dehydrogenase, however, increased continuously up to 4 h. 3 alpha, 20 beta-hydroxysteroid dehydrogenase and 3 beta, 17 beta-hydroxysteroid dehydrogenase syntheses seemed to be controlled by steroids in a non-coordinate manner.
    Hydroxysteroid Dehydrogenases
    Dihydrotestosterone
    BETA (programming language)
    Hydroxysteroid
    Alpha (finance)
    Hydroxysteroid Dehydrogenases
    Citations (5)
    1. Optimum conditions were established for determining the activities of the NADP(+)-linked enzymes, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and isocitrate dehydrogenase, in mosquito tissues. 2. The activity of each dehydrogenase was determined in samples of mosquitoes of different ages throughout the life-span. The specific-activity curves attained maximal values in the pupal or early adult period. From these maxima an 81% decrease in glucose 6-phosphate-dehydrogenase and 67% decrease in 6-phosphogluconate-dehydrogenase activities occurred after the tenth day of adult life; a 77% decrease in isocitrate-dehydrogenase activity occurred before the fifth day. 3. The activity differences were found in different body regions as well as in whole organisms. 4. Starvation of the larva or adult did not result in decreases in enzyme activity. 5. These findings support the hypothesis that the activities of enzymes that form NADPH are related to the biosynthetic activity, for the enzyme activities increased during the period of cellular growth and decreased during the aging period.
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    Citations (24)
    We report a potentiometric fully automated method for determining red cell glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase activities and the glucose 6-phosphate dehydrogenase/6-phosphogluconate dehydrogenase index using 25 microliters of whole blood. No sample pre-treatment (e.g., preparation of the haemolysate) is needed and the measurements are performed at pH 8.0 and 37 degrees C under the conditions recommended by the ICSH committee. The reproducibility was constantly good, with within-run CV of 1.0% (glucose 6-phosphate dehydrogenase) and 5.9% (glucose 6-phosphate dehydrogenase/6-phosphogluconate dehydrogenase) for activities in glucose 6-phosphate dehydrogenase non-deficient adults, and of 2.3% (glucose 6-phosphate dehydrogenase, G6PD) and 2.5% (glucose 6-phosphate dehydrogenase/6-phosphogluconate dehydrogenase) for G6PDMediterranean heterozygotes. Linearity was observed up to an activity of 2800 U/l of glucose 6-phosphate dehydrogenase. Results of glucose 6-phosphate dehydrogenase activity (U/l) in whole blood (y) correlated well with those obtained with the previously described monostarter assay, performed at pH 9.2 (y = 0.60x + 37; n = 80; r = 0.991). Results of 6-phosphogluconate dehydrogenase (U/l) in whole blood (y) correlated well with those obtained by the ICSH recommended method (x) (y = 0.779x - 44; n = 23; r = 0.991). Reference intervals are reported for glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and glucose 6-phosphate dehydrogenase/6-phosphogluconate dehydrogenase index relatively to normal, beta- and alpha-thalassaemic glucose 6-phosphate dehydrogenase non-deficient adults, to glucose 6-phosphate dehydrogenase deficient adult males and to G6PDMediterranean non-thalassaemic heterozygotes. We demonstrate that the diagnostic sensitivity of the glucose 6-phosphate dehydrogenase/6-phosphogluconate dehydrogenase index in detecting the G6PDMediterranean heterozygotes is superior to that of the glucose 6-phosphate dehydrogenase activity alone.
    Phosphogluconate dehydrogenase
    Citations (17)
    The secondary structure of glycerol-3-phosphate dehydrogenase was predicted from its amino acid sequence. The pattern of helices and sheets within the first half of the polypeptide as well as specific marker residues were consistent with the properties of the NAD binding domain in other dehydrogenases. The second half of the sequence shows similarities with the catalytic domain of glyceraldehyde-3-phosphate dehydrogenase. The resulting two-domain structure of glycerol-3-phosphate dehydrogenase allows the correct environment for the B specificity of the nicotinamide ring and the L-glycerol 3-phosphate substrate.
    Glycerol-3-phosphate dehydrogenase
    Sequence (biology)
    Glyceraldehyde 3-phosphate dehydrogenase