Histochemical localization of key glycolytic and related enzymes in adult Onchocerca fasciata

1994 ◽  
Vol 68 (4) ◽  
pp. 337-341 ◽  
Author(s):  
M.S. Omar ◽  
A.M.S. Raoof
Keyword(s):  
Body Wall ◽  
Distribution Patterns ◽  
Reproductive Organs ◽  
Pentose Phosphate ◽  
The Body ◽  
Active Components ◽  
Metabolizing Enzymes ◽  
Pentose Phosphate Pathways ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Low Activity

AbstractThe activities of some key enzymes of the glycolytic and pentose phosphate pathways were investigated histochemically in adult female Onchocerca fasciata (Nematoda: Filarioidea). The distribution patterns of phosphofructokinase (PFK), aldolase (ALD), glyceraldehyde 3-phosphate dehydrogenase (G3PDH) and glucose 6-phosphate dehydrogenase (G6PDH) in different tissues of the worm were determined by employing NitroBlue Tetrazolium (NBT). The glycolytic enzymes PFK, ALD, and G3PDH were distributed throughout the hypodermal tissue, somatic muscles and reproductive organs. These enzyme activities were predominantly expressed in the hypodermal and reproductive tissues, both of which appeared to be metabolically more active than adjacent tissues. The high activities of the enzymes studied in the hypodermal tissue when compared with the minimal or low activity in the intestinal epithelium support the assumption that the worm's intestine, in contrast to the body wall, plays no significant role in the nutrient acquisition process. The results emphasize that both the glycolytic and hexose monophosphate pathways of carbohydrate metabolism are active components in energy production and biosynthetic processes in the various tissues of the worm. The functional significance of these glucose-metabolizing enzymes has been discussed with regard to their location in the tissues concerned.

On spermatophore-producing aquatic microdrile oligochaetes (Annelida: Clitellata)

Zootaxa ◽  
2018 ◽  
Vol 4497 (1) ◽  
pp. 41
Author(s):  
PILAR RODRIGUEZ ◽  
STEVEN V. FEND
Keyword(s):  
Body Wall ◽  
Single Species ◽  
Reproductive Organs ◽  
The Body ◽  
Aquatic Oligochaetes

The formation of encapsulated spermatophores is exceptional among aquatic oligochaetes, although it seems to have occurred independently in several unrelated taxa. Among the microdriles, some variations appear unique to single species. The recently described lumbriculid Uktena riparia Fend et al. forms spermatophores in the male duct and attaches them within a deep spermathecal bursa. The attachment of spermatophores to the body wall, in the clitellar region, or in the vicinity of male or spermathecal pores has been reported in Paranadrilus Gavrilov, Bothrioneurum Štolc and some Aktedrilus Knöllner species. Anatomical comparison of reproductive organs suggests convergent development of glandular organs in the male duct or spermathecae, used for the formation, transfer and/or attachment of spermatophores to the concopulant worms. The presence of similar organs in Smithsonidrilus Brinkhurst, where spermatophores have not been reported, is also discussed. Furthermore, a lectotype is designated for Paranadrilus descolei Gavrilov, 1955. 

Respiratory pathways and fat synthesis in the developing castor oil seed

1979 ◽  
Vol 57 (9) ◽  
pp. 1008-1014 ◽  
Author(s):  
P. D. Simcox ◽  
W. Garland ◽  
V. DeLuca ◽  
D. T. Canvin ◽  
D. T. Dennis
Keyword(s):  
Fatty Acid ◽  
Castor Oil ◽  
Fatty Acid Biosynthesis ◽  
Acid Synthesis ◽  
Pentose Phosphate ◽  
Carboxylase Activity ◽  
Bisphosphate Carboxylase ◽  
Oil Seed ◽  
Pentose Phosphate Pathways ◽  
Glucose 6 Phosphate Dehydrogenase

During castor oil seed development, changes occur in the activities of enzymes involved in fatty acid biosynthesis, glycolysis, and the pentose phosphate pathways. The activities of acetyl-CoA carboxylase, phosphofructokinase, pyruvate kinase, glucose-6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase per seed increase during the phase of rapid oil synthesis in the endosperm. As the seed matures and the rate of fatty acid synthesis decreases, there is a corresponding diminution in the activities of these enzymes. An indication of the metabolic capacity of the plastids was determined by monitoring the ribulose-1,5-bisphosphate carboxylase activity in the endosperm.

scholarly journals Hemoglobin Köln Disease Occurring as a Fresh Mutation: Erythrocyte Metabolism and Survival

Blood ◽  
1971 ◽  
Vol 38 (6) ◽  
pp. 715-729 ◽  
Author(s):  
DENIS R. MILLER ◽  
ROBERT I. WEED ◽  
GEORGE STAMATOYANNOPOULOS ◽  
AKIRA YOSHIDA
Keyword(s):  
Methylene Blue ◽  
Osmotic Fragility ◽  
Pentose Phosphate ◽  
Cell Deformability ◽  
Red Cell Deformability ◽  
Globin Chains ◽  
Membrane Rigidity ◽  
Rate Of Decline ◽  
Pentose Phosphate Pathways ◽  
Glucose 6 Phosphate Dehydrogenase

Abstract Electrophoretic and fingerprinting studies in a patient with congenital hemolytic anemia revealed the presence of the unstable hemoglobin Köln (β98val→met). Examination of parents and siblings gave normal results. Extensive blood group and isozyme studies were consistent with the thesis that Hb Köln disease in the propositus was the result of a fresh mutation in one of his parent’s gametes. In the propositus, the activities of enzymes of the Embden-Meyerhof and pentose phosphate pathways were increased, but the level of ATP was decreased. Methemoglobin reduction was delayed when the NADPH-dependent system was utilized with added methylene blue and gave a false-positive result in the glucose-6-phosphate dehydrogenase screening test. Methemoglobin reduction in the absence of methylene blue was normal. Increased methemoglobin and Heinz body formation, decreased osmotic fragility, decreased red cell deformability, and a disproportionate potassium loss without sodium gain occurred with metabolic depletion. The rate of decline of glutathione in propositus’ cells paralleled that in normal cells. Autologous survival of Hb Köln cells was decreased but was not compromised further by oxidant drugs. Marked splenic sequestration of Hb Köln erythrocytes was demonstrated, and an excellent response to splenectomy with improved erythrocyte survival was observed. The intracellular precipitation of unstable globin chains, intracellular dehydration, and increased membrane rigidity probably all contribute to the splenic entrapment of these erythrocytes.

scholarly journals Two high-rate pentose-phosphate pathways in cancer cells

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Vanessa Cossu ◽  
Marcella Bonanomi ◽  
Matteo Bauckneht ◽  
Silvia Ravera ◽  
Nicole Righi ◽  
...  
Keyword(s):  
Gene Silencing ◽  
Cell Biology ◽  
Pentose Phosphate ◽  
Metabolic Reprogramming ◽  
High Rate ◽  
Similar Degree ◽  
Cell Content ◽  
Relevant Role ◽  
Pentose Phosphate Pathways ◽  
Glucose 6 Phosphate Dehydrogenase

AbstractThe relevant role of pentose phosphate pathway (PPP) in cancer metabolic reprogramming has been usually outlined by studying glucose-6-phosphate dehydrogenase (G6PD). However, recent evidence suggests an unexpected role for a less characterized PPP, triggered by hexose-6-phosphate dehydrogenase (H6PD) within the endoplasmic reticulum (ER). Studying H6PD biological role in breast and lung cancer, here we show that gene silencing of this reticular enzyme decreases cell content of PPP intermediates and d-ribose, to a similar extent as G6PD silencing. Decrease in overall NADPH content and increase in cell oxidative status are also comparable. Finally, either gene silencing impairs at a similar degree cell proliferating activity. This unexpected response occurs despite the absence of any cross-interference between the expression of both G6PD and H6PD. Thus, overall cancer PPP reflects the contribution of two different pathways located in the cytosol and ER, respectively. Disregarding the reticular pathway might hamper our comprehension of PPP role in cancer cell biology.

scholarly journals Phosphonomethyl analogues of hexose phosphates

1976 ◽  
Vol 155 (2) ◽  
pp. 433-441 ◽  
Author(s):  
D Webster ◽  
W. R Jondorf ◽  
H B. F. Dixon
Keyword(s):  
Pentose Phosphate ◽  
Phosphate Group ◽  
Phosphogluconate Dehydrogenase ◽  
Fructose 1,6 Bisphosphatase ◽  
Pentose Phosphate Pathways ◽  
Fructose 1,6 Bisphosphate ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Hexose Phosphates

The analogue of fructose 1,6-bisphosphate in which the phosphate group, -O-PO3H2, on C-6 is replaced by the phosphonomethyl group, -CH2-PO3H2, was made enzymically from the corresponding analogue of 3-phosphoglycerate. It was a substrate for aldolase, which was used to form it, but not for fructose 1,6-bisphosphatase. It was hydrolysed chemically to yield the corresponding analogue of fructose 6-phosphate [i.e. 6-deoxy-6-(phosphonomethyl)-D-fructose, or, more strictly, 6,7-dideoxy-7-phosphono-D-arabino-2-heptulose]. This proved to be a substrate for the sequential actions of glucose 6-phosphate isomerase, glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. Thus seven out of the nine enzymes of the glycolytic and pentose phosphate pathways so far tested catalyse the reactions of the phosphonomethyl isosteres of their substrates.

scholarly journals Post-translational Regulation of Glucose-6-phosphate Dehydrogenase Activity in (Pre)neoplastic Lesions in Rat Liver

2003 ◽  
Vol 51 (1) ◽  
pp. 105-112 ◽  
Author(s):  
Wilma M. Frederiks ◽  
Klazina S. Bosch ◽  
Jonas S.S.G. De Jong ◽  
Cornelis J.F. Van Noorden
Keyword(s):  
Pentose Phosphate Pathway ◽  
Translational Regulation ◽  
Distribution Patterns ◽  
Liver Parenchyma ◽  
Pentose Phosphate ◽  
G6pd Activity ◽  
Kinetic Properties ◽  
Mrna Levels ◽  
Neoplastic Lesions ◽  
Glucose 6 Phosphate Dehydrogenase

Glucose-6-phosphate dehydrogenase (G6PD; EC 1.1.1.49) is the key regulatory enzyme of the pentose phosphate pathway and produces NADPH and riboses. In this study, the kinetic properties of G6PD activity were determined in situ in chemically induced hepatocellular carcinomas, and extralesional and control parenchyma in rat livers and were directly compared with those of the second NADPH-producing enzyme of the pentose phosphate pathway, phosphogluconate dehydrogenase (PGD). Distribution patterns of G6PD activity, protein, and mRNA levels were also compared to establish the regulation mechanisms of G6PD activity. In (pre)neoplastic lesions, the Vmax of G6PD was 150-fold higher and the Km for G6P was 10-fold higher than in control liver parenchyma, whereas in extralesional parenchyma, the Vmax was similar to that in normal parenchyma but the Km was fivefold lower. This means that virtual fluxes at physiological substrate concentrations are 20-fold higher in lesions and twofold higher in extralesional parenchyma than in normal parenchyma. The Vmax of PGD was fivefold higher in lesions than in normal and extralesional liver parenchyma, whereas the Km was not affected. Amounts of G6PD protein and mRNA were similar in lesions and in extralesional liver parenchyma. These results demonstrate that G6PD is strongly activated post-translationally in (pre)neoplastic lesions to produce NADPH.

scholarly journals Mutational Analyses of Glucose Dehydrogenase and Glucose-6-Phosphate Dehydrogenase Genes in Pseudomonas fluorescens Reveal Their Effects on Growth and Alginate Production

2015 ◽  
Vol 81 (10) ◽  
pp. 3349-3356 ◽  
Author(s):  
Susan Maleki ◽  
Mali Mærk ◽  
Svein Valla ◽  
Helga Ertesvåg
Keyword(s):  
Pseudomonas Fluorescens ◽  
Glucose Dehydrogenase ◽  
Central Carbon Metabolism ◽  
Pentose Phosphate ◽  
Content Type ◽  
Alginate Production ◽  
Metabolism Enzymes ◽  
Pentose Phosphate Pathways ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
The Impact

ABSTRACTThe biosynthesis of alginate has been studied extensively due to the importance of this polymer in medicine and industry. Alginate is synthesized from fructose-6-phosphate and thus competes with the central carbon metabolism for this metabolite. The alginate-producing bacteriumPseudomonas fluorescensrelies on the Entner-Doudoroff and pentose phosphate pathways for glucose metabolism, and these pathways are also important for the metabolism of fructose and glycerol. In the present study, the impact of key carbohydrate metabolism enzymes on growth and alginate synthesis was investigated inP. fluorescens. Mutants defective in glucose-6-phosphate dehydrogenase isoenzymes (Zwf-1 and Zwf-2) or glucose dehydrogenase (Gcd) were evaluated using media containing glucose, fructose, or glycerol. Zwf-1 was shown to be the most important glucose-6-phosphate dehydrogenase for catabolism. Both Zwf enzymes preferred NADP as a coenzyme, although NAD was also accepted. Only Zwf-2 was active in the presence of 3 mM ATP, and then only with NADP as a coenzyme, indicating an anabolic role for this isoenzyme. Disruption ofzwf-1resulted in increased alginate production when glycerol was used as the carbon source, possibly due to decreased flux through the Entner-Doudoroff pathway rendering more fructose-6-phosphate available for alginate biosynthesis. In alginate-producing cells grown on glucose, disruption ofgcdincreased both cell numbers and alginate production levels, while this mutation had no positive effect on growth in a non-alginate-producing strain. A possible explanation is that alginate synthesis might function as a sink for surplus hexose phosphates that could otherwise be detrimental to the cell.

Memoirs: On a New Hermaphrodite Syllid

1930 ◽  
Vol s2-73 (292) ◽  
pp. 651-666
Author(s):  
E. S. GOODRICH
Keyword(s):  
New Species ◽  
Body Wall ◽  
Reproductive Organs ◽  
The Body ◽  
Advanced Stage ◽  
Sperm Duct ◽  
Cuticular Membrane ◽  
Constant Structure ◽  
Successive Generations ◽  
A New Species

In this paper a new species of Syllid, named Pionosyllis neapolitana, is described, whose chief characteristics are that it is hermaphrodite, and has reproductive organs of remarkably complex and constant structure.1 There are a pair of testes in each of the segments 10, 11, and 12, and a pair of ovaries in every segment from the thirteenth backwards throughout the region of the true intestine. A pair of nephridia with small nephridiostomes occurs in every segment from the fifth backwards, except in segments 11, 12, and 13, in which they become transformed into nephromixia functioning as sperm-ducts. Each sperm-duct is provided with a ciliated coelomostome opening into a male segment, and its postseptal tubule is enlarged into a sperm-sac where the spermatozoa form spermatophores. Presumably copulation takes place, since spermatophores are found lodged in paired spermathecae opening to the exterior on every female segment. One ovum at a time in every ovary enlarges and is extruded dorsally, apparently by breaking through the body-wall. The ova by this time are fertilized. They develop to an advanced stage surrounded by a cuticular membrane, and attached in pairs to every female segment. The young escape from the membrane when about eighteen segments have been formed. When the ova pass to the exterior they become attached to the laterodorsal surface of the female segments by means of fixing threads formed by special paired organs of fixation. These organs are derived from the spermathecae. Possibly successive generations of ova are extruded, but this has not yet been observed, nor is it known whether the fixing organs can again function as spermathecae. Exactly how and when fertilization takes place has not so far been determined.

scholarly journals The emerging role of targeting cancer metabolism for cancer therapy

Tumor Biology ◽  
2020 ◽  
Vol 42 (10) ◽  
pp. 101042832096528
Author(s):  
Pegah Farhadi ◽  
Reza Yarani ◽  
Sadat Dokaneheifard ◽  
Kamran Mansouri
Keyword(s):  
Cancer Therapy ◽  
Cancer Cells ◽  
Cancer Metabolism ◽  
Aerobic Glycolysis ◽  
Pentose Phosphate ◽  
The Body ◽  
Acid Oxidation ◽  
Normal Cells ◽  
Cancer Hallmarks ◽  
Pentose Phosphate Pathways

Glucose, as the main consuming nutrient of the body, faces different destinies in cancer cells. Glycolysis, oxidative phosphorylation, and pentose phosphate pathways produce different glucose-derived metabolites and thus affect cells’ bioenergetics differently. Tumor cells’ dependency to aerobic glycolysis and other cancer-specific metabolism changes are known as the cancer hallmarks, distinct cancer cells from normal cells. Therefore, these tumor-specific characteristics receive the limelight as targets for cancer therapy. Glutamine, serine, and fatty acid oxidation together with 5-lipoxygenase are main pathways that have attracted lots of attention for cancer therapy. In this review, we not only discuss different tumor metabolism aspects but also discuss the metabolism roles in the promotion of cancer cells at different stages and their difference with normal cells. Besides, we dissect the inhibitors potential in blocking the main metabolic pathways to introduce the effective and non-effective inhibitors in the field.

scholarly journals The activities of fructose diphosphatase in flight muscles from the bumble-bee and role of this enzyme in heat generation

1972 ◽  
Vol 128 (1) ◽  
pp. 89-97 ◽  
Author(s):  
E. A. Newsholme ◽  
B. Crabtree ◽  
S. J. Higgins ◽  
S. D. Thornton ◽  
Carole Start
Keyword(s):  
Flight Muscle ◽  
Maximum Activity ◽  
The Body ◽  
Bumble Bee ◽  
Rest Periods ◽  
Flight Muscles ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Hydrolysis Of ◽  
Low Activity

1. The maximum catalytic activities of fructose diphosphatase from flight muscles of bumble-bees (Bombus spp.) are at least 30-fold those reported for the enzyme from other tissues. The maximum activity of fructose diphosphatase in the flight muscle of any particular bee is similar to that of phosphofructokinase in the same muscle, and the activity of hexokinase is similar to or greater than the activity of phosphofructokinase. There is no detectable activity of glucose 6-phosphatase and only a very low activity of glucose 6-phosphate dehydrogenase in these muscles. The activities of both fructose diphosphatase and phosphofructokinase vary inversely with the body weight of the bee, whereas that of hexokinase is relatively constant. 2. There is no significant hydrolysis of fructose 1-phosphate, fructose 6-phosphate, glucose 1,6-diphosphate and glycerol 3-phosphate by extracts of bumble-bee flight muscle. 3. Fructose 1,6-diphosphatase from bumble-bee flight muscle and from other muscles is inhibited by Mn2+and univalent cations; the potency of inhibition by the latter varies in the order Li+>Na+>K+. However, the fructose diphosphatase from bumble-bee flight muscle is different from the enzyme from other tissues in that it is not inhibited by AMP. 4. The contents of ATP, hexose monophosphates, fructose diphosphate and triose phosphates in bumble-bee flight muscle showed no significant changes between rest and flight. 5. It is proposed that both fructose diphosphatase and phosphofructokinase are simultaneously active and catalyse a cycle between fructose 6-phosphate and fructose diphosphate in resting bumble-bee flight muscle. Such a cycle would produce continuous hydrolysis of ATP, with the release of energy as heat, which would help to maintain the thoracic temperature during rest periods at a level adequate for flight.

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