Constancy of enzyme electrofocusing patterns in a stand of the lichen Umbilicaria mammulata

1986 ◽  
Vol 64 (9) ◽  
pp. 1928-1934 ◽  
Author(s):  
C. Hageman ◽  
D. Fahselt

Thalli of the lichen Umbilicaria mammulata (Ach.) Tuck, were collected from one site, 24 at each of five different sampling times, over a period of 1 year. Protein extracts from each individual thallus were subjected to isoelectric focusing, followed by specific staining for eight enzyme systems (mannitol dehydrogenase, isocitrate dehydrogenase, 6-phosphogluconate dehydrogenase, glucose-6-phosphate dehydrogenase, glutamate dehydrogenase, superoxide dismutase, esterase, and alkaline phosphatase). A total of 55 bands were resolved, 25 of which were constant in all thalli through all sampling dates. Principal components analysis of the electromorph data showed the existence of groups corresponding to sets of thalli collected at the same times; esterase and alkaline phosphatase variation were primarily responsible for these groupings. Banding patterns of 6-phosphogluconate dehydrogenase and superoxide dismutase were constant regardless of date of collection. Most bands of glucose-6-phosphate dehydrogenase and glutamate dehydrogenase were consistent through all sampling times, but each system exhibited one band that differed in frequency from one collection date to another. Electromorphs of mannitol dehydrogenase and isocitrate dehydrogenase exhibited only minor variability. Dehydrogenase enzymes, since they tended to vary least from one sampling time to the next, can thus be used more readily for taxonomic purposes. If esterases and alkaline phosphatases are to be applied as taxonomic criteria, samples for comparison should be collected simultaneously.

1984 ◽  
Vol 26 (4) ◽  
pp. 459-468 ◽  
Author(s):  
D. B. Neale ◽  
J. C. Weber ◽  
W. T. Adams

Methods for resolving electrophoretic variants from extracts of needle tissue of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) are described, and the inheritance of 12 of at least 15 loci that control allozymes from 11 enzyme systems are established. Evidence for the inheritance of allozyme variants was obtained in three ways: (i) comparison in seed orchard clones of allozyme genotypes determined from both megagametophyte and needle tissue; (ii) analysis of segregating full-sib progenies of seed orchard clones; and (iii) comparison of needle allozyme pattern phenotypes to previously reported embryo phenotypes. Ten of the 12 loci (coding phosphoglucomutase, PGM(1) and PGM(2); glycerate dehydrogenase, GLYDH; phosphoglucose isomerase, PG1(2); glutamate dehydrogenase, GDH; glucose-6-phosphate dehydrogenase, G-6PD; 6-phosphogluconate dehydrogenase, 6-PGD(1); isocitrate dehydrogenase, IDH; diaphorase, DIA(2); malate dehydrogenase, MDH(1)) produce clear bands in seed tissue; however, glutamate oxaloacetate transaminase GOT(3) (N) was not found in seeds and shikimic dehydrogenase (SDH) could only be clearly resolved in needles (N). Several enzymes active in seed tissue could not be detected in needle tissues.Key words: Douglas-fir, needle tissue isozymes, inheritance.


1992 ◽  
Vol 24 (2) ◽  
pp. 181-192
Author(s):  
Dianne Fahselt

Abstract Samples of Cladonia mitis were collected from three microhabitats within an open field in eastern Hokkaido, Japan. Two sets of sample thalli were taken in close proximity to geothermal vents and a third from a neighbouring area not directly affected by outgassings. Enzymes were extracted and separated by isoelectric focusing, and multiple enzyme forms of three oxidoreductases, glucose-6-phosphate dehydrogenase, glutamate dehydrogenase and superoxide dismutase, and two hydrolases, esterase and alkaline phosphatase, were examined. Similarities between microhabitats based on electrophoretic results were calculated using Jaccard's similarity coefficient and expressed graphically through the complementary techniques of clustering and ordination. All of the major differences in isozyme patterns between remote samples and those near fumaroles were in the two highly polymorphic enzymes, esterase and alkaline phosphatase. Differences were as great or greater than those between geographically separated conspecific populations of lichens examined previously. In the more sulphurous microhabitats, nine bands were much more frequent and eight much less so than in locations further from the source of gases.


1967 ◽  
Vol 56 (2) ◽  
pp. 231-243 ◽  
Author(s):  
H. Schmidt ◽  
I. Noack ◽  
H. Walther ◽  
K. D. Voigt

ABSTRACT The first significant increase of weight, RNA and protein was observed in the uterus of spayed rats twelve hours after the intraperitoneal administration of a single dose of 1 μg oestradiol. There was no significant increase of DNA. At the same time the activities of glucose-6-phosphate dehydrogenase, fructose-1,6-diphosphate aldolase, isocitrate dehydrogenase and leucine aminopeptidase had increased significantly. Twentyfour hours after the injection the augmented values began to decline. Three injections of 1 μg oestradiol, given at 24 hour intervals obtained similar changes, the only difference being that these changes were more marked and that a DNA increase was also observed. The augmentation of protein, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and fructose-1,6-diphosphate aldolase content of cells induced by repeated oestradiol injections was inhibited partly by 1 mg progesterone when administered together with the last dose of oestradiol. During the normal oestrus cycle of the rat uterus an increase of uterine weight, DNA and RNA content and also of glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and 1,6-diphosphate aldolase activities was observed, whereas isocitrate dehydrogenase, malate dehydrogenase and leucine aminopeptidase did not change significantly. It would appear that the changes after exogenous hormone administration reflect those of the normal cycle as regards both their extent and timing. The importance of these findings in connection with hormone-induced pathways of uterine metabolism is discussed.


1965 ◽  
Vol 49 (1) ◽  
pp. 58-64 ◽  
Author(s):  
M. H. Nielson ◽  
J. C. Warren

ABSTRACT The endogenous activities of four major supernatant enzymes which produce TPNH (glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, malate dehydrogenase and isocitrate dehydrogenase) were quantitated in both normal and pathologic human ovarian tissues. The atrophic ovary demonstrated the lowest relative activity of the pentose shunt dehydrogenases, whereas luteinized tissues displayed the highest. During the course of its life cycle, the corpus luteum of the nonpregnant female displayed a progressive rise in isocitrate dehydrogenase and a concomitant fall in glucose-6-phosphate dehydrogenase activities. The corpus luteum of pregnancy, studied at term, demonstrated the highest levels of activity of all the four enzymes quantitated.


1985 ◽  
Vol 52 (4) ◽  
pp. 501-506 ◽  
Author(s):  
Murray R. Grigor ◽  
Peter E. Hartmann

SUMMARYThe activities of glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, isocitrate dehydrogenase, malic enzyme, lactate dehydrogenase and malate dehydrogenase have been determined in secreted milk from sows, rats and rabbits. Within each species, although there was considerable variation in the absolute activities of these enzymes, the relative activities were similar to those observed for, or previously published for mammary homogenates. The only exception was milk glucose 6-phosphate dehydrogenase which tended to lose activity upon prolonged storage in the mammary gland. These results suggest that the pattern of milk enzymes can be an accurate reflection of that occurring in the mammary gland.


1970 ◽  
Vol 119 (1) ◽  
pp. 5-15 ◽  
Author(s):  
S. J. H. Ashcroft ◽  
P. J. Randle

1. Glucose-phosphorylating and glucose 6-phosphatase activities, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, NADP+-linked isocitrate dehydrogenase, `malic' enzyme and pyruvate carboxylase were assayed in homogenates of normal mouse islets. 2. Two glucose-phosphorylating activities were detected; the major activity had Km 0.075mm for glucose and was inhibited by glucose 6-phosphate (non-competitive with glucose) and mannoheptulose (competitive with glucose). The other (minor) activity had a high Km for glucose (mean value 16mm) and was apparently not inhibited by glucose 6-phosphate. 3. Glucose 6-phosphatase activity was present in amounts comparable with the total glucose-phosphorylating activity, with Km 1mm for glucose 6-phosphate. Glucose was an inhibitor and the inhibition showed mixed kinetics. No inhibition of glucose 6-phosphate hydrolysis was observed with mannose, citrate or tolbutamide. The inhibition by glucose was not reversed by mannoheptulose. 4. 6-Phosphogluconate dehydrogenase had Km values of 2.5 and 21μm for NADP+ and 6-phosphogluconate respectively. 5. Glucose 6-phosphate dehydrogenase had Km values of 4 and 22μm for NADP+ and glucose 6-phosphate. The Km for glucose 6-phosphate was considerably below the intra-islet concentration of glucose 6-phosphate at physiological extracellular glucose concentrations. The enzyme had no apparent requirement for cations. Of a number of possible modifiers of glucose 6-phosphate dehydrogenase, only NADPH was inhibitory. The inhibition by NADPH was competitive with NADP+ and apparently mixed with respect to glucose 6-phosphate. 6. NADP+–isocitrate dehydrogenase was present but the islet homogenate contained little, if any, `malic' enzyme. The presence of pyruvate carboxylase was also demonstrated. 7. The results obtained are discussed with reference to glucose phosphorylation and glucose 6-phosphate oxidation in the intact mouse islet, and the possible nature of the β-cell glucoreceptor mechanism.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Marina Leterrier ◽  
Juan B. Barroso ◽  
Raquel Valderrama ◽  
José M. Palma ◽  
Francisco J. Corpas

NADPH regeneration appears to be essential in the mechanism of plant defence against oxidative stress. Plants contain several NADPH-generating dehydrogenases including isocitrate dehydrogenase (NADP-ICDH), glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), and malic enzyme (ME). InArabidopsisseedlings grown under salinity conditions (100 mM NaCl) the analysis of physiological parameters, antioxidant enzymes (catalase and superoxide dismutase) and content of superoxide radical (O2  ∙−), nitric oxide (NO), and peroxynitrite (ONOO-) indicates a process of nitro-oxidative stress induced by NaCl. Among the analysed NADPH-generating dehydrogenases under salinity conditions, the NADP-ICDH showed the maximum activity mainly attributable to the root NADP-ICDH. Thus, these data provide new insights on the relevance of the NADP-ICDH which could be considered as a second barrier in the mechanism of response against the nitro-oxidative stress generated by salinity.


2019 ◽  
Vol 11 (1) ◽  
pp. 116-120
Author(s):  
Mamata Ranot ◽  
Rajesh Sharma

Pinus gerardiana (Chilgoza) is a small to medium sized evergreen tree yielding a highly valuable edible nut. The present investigations were undertaken to assess the different isozymes in Chilgoza pine. Seven isozymes viz., MDH (Malate dehydrogenase), GDH (Glutamate dehydrogenase), SKDH (Shikimic acid dehydrogenase), 6PGDH (6-Phosphogluconate dehydrogenase), MNR (Menadione reductase), IDH (Isocitrate dehydrogenase) and ADH (Alcohol dehdrogenase) were studied. A total of sixteen gene loci were recorded for seven enzyme systems out of which 6 loci namely MDH- A, 6PGDH- A, SKDH- A, IDH- B, MNR- B and ADH- A were polymorphic whereas the remaining ten gene loci i.e. MDH- B, MDH- C, MDH- D, GDH- A, 6PGDH- B, SKDH- B, IDH- A, MNR- A, MNR- B and ADH- B showed no variation. The percentage of polymorphic loci and average number of alleles per locus are one of the useful criterions for comparing species of populations for genetic diversity.


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