Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.1.1.49 (glucose-6-phosphate dehydrogenase)
 7,794 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Penicillamine, a cysteine analog with a reduced sulfhydryl group, has been used in this laboratory for the treatment of hereditary avian dystrophy. The drug delays the onset of symptoms and alleviates the debilitating aspects of the disease. To study the mechanism of drug action, the effects of penicillamine on white and red muscles of dystrophic chickens were examined with regard to the specific activities of the soluble enzymes glyceraldehyde-3-phosphate dehydrogenase, acetylphosphatase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glutathione reductase, glutathione preoxidase, superoxide dismutase, and catalase. The sulfhydryl contents of the soluble proteins and the concentration of myoglobin were also determined. In white dystrophic muscle (pectoral), there were large alterations in the various enzymatic activities compared to normal levels. In the DISCUSSION, these changes are related to the pathogenesis of the disease and to the adaptive response for protection of the severely affected fast fibers. Red dystrophic muscles (thigh) were minimally involved, in accordance with the known sparing action of the slow fiber type. The results suggested that the disease process in dystrophic muscle may be due to oxidation of the essential sulfhydryl groups of proteins. Penicillamine may produce therapeutic effects by altering the intracellular redox status, thereby promoting better regulation of enzymatic activity, membrane stability, and improved muscle function.
 ...
PMID:Mechanism of action of penicillamine in the treatment of avian muscular dystrophy. 28 17

The denaturation of eight purified yeast enzymes, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, 3-phosphoglycerate kinase, alcohol dehydrogenase, beta-fructosidase, hexokinase and glucose-6-phosphate isomerase, promoted under controlled conditions by the free fatty acids myristic and oleic, is selective. Glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate:NADP+ 1 oxidoreductase, EC 1.1.1.49) is extremely sensitive to destabilization and was studied in greater detail. Results show that chain length and degree of unsaturation of fatty acids are important to their destabilizing effect, and that ligands of the enzyme can afford protection. The denaturation process results in more than one altered form. These results can be viewed in the perspective of the possibility that amphipathic substances, and in particular free fatty acids, may play a role for enzyme degradation in vivo, by initiating steps of selective denaturation.
 ...
PMID:Selective denaturation of several yeast enzymes by free fatty acids. 35 87

The levels of 6-phosphogluconate dehydrogenase and glucose 6-phosphate dehydrogenase are subject to metabolic regulation; they increased three- to fivefold with increasing growth rate.
 ...
PMID:Growth-rate-dependent alteration of 6-phosphogluconate dehydrogenase and glucose 6-phosphate dehydrogenase levels in Escherichia coli K-12. 38 88

While a null activity mutant allele of the structural gene for 6-phosphogluconate dehydrogenase in Drosophila melanogaster is lethal, a similar mutation for glucose-6-phosphate dehydrogenase is not. Double mutant combinations lacking both enzyme activities, obtained either by recombination or by mutagen treatment of a chromosome bearing the lethal allele, result in a restoration of viability. The indispensability of the pentose phosphate shunt in Drosophila appears to depend upon the specific position of the block within the pathway.
 ...
PMID:Genetic rescue of a lethal "null" activity allele of 6-phosphogluconate dehydrogenase in Drosophila melanogaster. 40 11

The molecular nature of lethal and semilethal mutations in the Pgd locus of D. melanogaster coding for 6-phosphogluconate dehydrogenase (6PGD) was studied. All the 11 mutations affect the structural gene of the Pgd locus: 3 semilethal mutations resulted in altered 6PGD molecules with decreased catalytic activities; the rest 8 lethals were "null" alleles characterized by mutant polypeptides capable of reacting with antisera against highly purified 6PGD. "Null" or low activity alleles for glucose-6-phosphate dehydrogenase induced by ethyl methanesulfonate were shown to be suppressores for the lethal mutations in the Pgd locus. A monocistronic type of organization of the Pgd locus is suggested taking into account the biochemical mechanism of suppression of the Pgd-lethals and their location in the structural gene coding for 6PGD.
 ...
PMID:Investigations on the organization of genetic loci in Drosophila melanogaster: lethal mutations affecting 6-phosphogluconate dehydrogenase and their suppression. 40 44

Carbohydrate metabolism by four rat hepatoma cell lines in culture, namely, Reuber H35, MH1C1, RLC, and HTC, has been investigated. Glucose utilization by H35 and MH1C1 cells is lower than that by RLC and HTC cells. The four cell lines also differ with respect to the accumulation of lactic acid in the growth medium; in particular, H35 cells show uptake of lactic acid, rather than accumulation in the medium. Specific activities of a number of enzymes involved in glycolysis, gluconeogenesis, pentose phosphate pathway, and glycogen formation were determined in the four cell lines. A direct relationship between the differences was found for the activities of some enzymes belonging to carbohydrate metabolism, namely, hexokinase, pyruvate kinase, aldolases A and B, glucose-6-phosphate dehydrogenase, and phosphogluconate dehydrogenase and the differences found for glucose utilization by the different cell lines.
 ...
PMID:Comparative studies of glucose metabolism in HTC, RLC, MH1C1, and Reuber H35 rat hepatoma cells. 42 45

The activities of glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and transketolase were studied in the cytoplasmic fractions of transplanted mouse hepatomas differing in their growth rates, and in the liver, spleen and cortical layer of kidneys of tumour carriers and normal mice. It was shown that transplantation of hepatomas changes the activity of the pentose phosphate pathway enzymes in tumour carrier tissues unaffected by neoplasm. Deviations from normalcy were mainly similar to those observed in the hepatomas. The changes in the enzymatic activities were especially well-pronounced in the mice having rapidly growing hepatomas. This may be due to a generalized effect of the tumour on the organism, which is concurrent with malignancy.
 ...
PMID:[Activities of dehydrogenases of the pentose phosphate pathway and transketolase in transplanted mouse hepatomas with different growth rates and in organs of tumor carriers]. 45 18

Blood samples collected in a single Pygmy tribe, the Aka, living in Bokoka district (Central African Empire) were investigated with respect to the phenotype and gene frequencies of the following 12 enzyme systems: acid phosphatase, adenosine deaminase, adenylate kinase, carbonic anhydrase, esterase D, glucose-6-phosphate dehydrogenase, malate dehydrogenase, phosphoglucomutase 1, phosphoglucomutase 2, phosphogluconate dehydrogenase, superoxide dismutase and serum cholinesterase variants (locus E1 and E2). The data obtained in the study of genetic polymorphisms of this isolated and inbred population show a specific pattern with the following characteristics: the very low frequency of PGDB and pa alleles; the existence of two rare PGM variants at the PGM2 locus, typical PGM26Pyg (4.2%) and PGM29 (0.2%); the high frequency of the pr allele (10.8%) and CAII2 (8.22%) and ESD2 genes (18.4%). Furthermore, at the G6PD locus four distinct alleles have been found: the negroid GdA- (4%) and GdA+ (16%), the common GdB+ (79.2%)--, and the rare Gd+Ibadan Austin (0.7%). Cholinesterase typings disclosed the presence of the uncommon E1f and E1s genes distributed within a single breeding unit. The results are compared with other data previously reported on South African Khoisan and some Negroid populations; the particular genetic background of Pygmies is discussed.
 ...
PMID:Population genetic studies of the Aka pygmies (Central Africa): a survey of red cell and serum enzymes. 46 35

Kinetic properties of human hair root glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were studied in order to optimize the assay of these enzymes in lysates from single hair roots. In contrast to previously reported methods, an excess of purified 6-phosphogluconate dehydrogenase was added to the glucose-6-phosphate dehydrogenase reaction mixtures, thus allowing a more exact quantification of glucose-6-phosphate dehydrogenase activity. Although enzyme histochemical techniques suggest a similar distribution of hair root glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase, enzyme assays on hair root segments after microdissection nevertheless indicate differences in the distribution of these enzymes. Upon storage a gradual drop in the activity of both hair root enzymes was found, but the rate of decrease in enzyme activity was about equal: the enzyme activity ratio was, therefore, not affected. This opens interesting possibilities for mailing hair roots for screening purposes without any special precautions.
 ...
PMID:Glucose-6-phosphate dehydrogenase deficiency: biochemical and histochemical studies on hair roots for carrier detection. 46 70

Blood samples were collected monthly over a nine-month period from 19 high-producing Holstein-Friesian dairy cows. Dry cows on the lowest (13 per cent) protein ration had the highest mean values for packed cell volume (PCV), haemoglobin (Hb) and red blood cells (RBC). Among the lactating cows, the group on the 13 per cent protein diet had the highest mean PCV, Hb and RBC values. Other constituents were not affected significantly by dietary protein levels. Packed cell volume, RBC, Hb, serum iron (SI), iron binding capacity (IBC) and serum albumin concentrations decreased early in lactation and rose to pre-lactation levels by mid-lactation. PCV and Hb concentrations remained low for periods up to four months. RBC count was lowest in the second month while albumin concentration was lowest in the first month and remained low up to the second month. IBC was lowest in the first month of lactation while SI concentrations were lowest in the third month. There were no significant variations in the activities of erythrocyte glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD) and reduced glutathione (GSH). The 13 per cent protein ration had no anaemia-inducing effect on the cows.
 ...
PMID:Effects of dietary protein and stage of lactation on the haematology and erythrocyte enzymes activities of high-producing dairy cattle. 47 89


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>