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)

A 52 yr old Caucasian female (F. E.) had hemolytic anemia, a leukemoid reaction, and fatal sepsis due to Escherichia coli. Her leukocytes ingested bacteria normally but did not kill catalase positive Staphylococcus aureus, Escherichia coli, and Serratia marcescens. An H(2)O(2)-producing bacterium, Streptococcus faecalis, was killed normally. Granule myeloperoxidase, acid and alkaline phosphatase, and beta glucuronidase activities were normal, and these enzymes shifted normally to the phagocyte vacuole (light and electron microscopy). Intravacuolar reduction of nitroblue tetrazolium did not occur. Moreover, only minimal quantities of H(2)O(2) were generated, and the hexose monophosphate shunt (HMPS) was not stimulated during phagocytosis. These observations suggested the diagnosis of chronic granulomatous disease. However, in contrast to control and chronic granulomatous disease leukocytes, glucose-6-phosphate dehydrogenase activity was completely absent in F. E. leukocytes whereas NADH oxidase and NADPH oxidase activities were both normal. Unlike chronic granulomatous disease, methylene blue did not stimulate the hexose monophosphate shunt in F. E. cells. Thus, F. E. and chronic granulomatous disease leukocytes appear to share certain metabolic and bactericidal defects, but the metabolic basis of the abnormality differs. Chronic granulomatous disease cells lack oxidase activity which produces H(2)O(2); F. E. cells had normal levels of oxidase activity but failed to produce NADPH due to complete glucose-6-phosphate dehydrogenase deficiency. These data indicate that a complete absence of leukocyte glucose-6-phosphate dehydrogenase with defective hexose monophosphate shunt activity is associated with low H(2)O(2) production and inadequate bactericidal activity, and further suggest an important role for NADPH in the production of H(2)O(2) in human granulocytes.
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PMID:Complete deficiency of leukocyte glucose-6-phosphate dehydrogenase with defective bactericidal activity. 440 Dec 71

1. The products of the lactoperoxidase-catalysed oxidation of thiocyanate by hydrogen peroxide were sulphate, carbon dioxide and ammonia. Cyanate, sulphite and a compound showing increased extinction at 235mmu (the ;235 compound') were intermediate oxidation products. 2. Two of the intermediates acted as electron acceptors in the oxidation of NADH(2). Thus NADH(2) was oxidized by sulphite in the presence of lactoperoxidase (EC 1.11.1.7) and Mn(2+) and by the ;235 compound' in the presence of an enzyme, the NADH(2)-oxidizing enzyme, present in extracts of lactoperoxidase-resistant streptococci. Sulphur dicyanide also acted as an electron acceptor in the latter reaction. The ;235 compound' was also reduced non-enzymically by sulphite. 3. The glycolysis of lactoperoxidasesensitive streptococci suspended in glucose solution was not inhibited by sulphite, cyanate, cyanide or the ;235 compound' but was inhibited by sulphur dicyanide. The inhibition by 0.1mm-sulphur dicyanide could be reversed, as could that caused by lactoperoxidase, thiocyanate and hydrogen peroxide, by washing the cells or by the addition of a cell-free extract of a lactoperoxidase-resistant streptococcus. 4. The effects of 0.1mm-sulphur dicyanide on catabolic enzymes of resting streptococci were very similar to those of the lactoperoxidase-thiocyanate-hydrogen peroxide system. Thus hexokinase was completedly inhibited, glucose 6-phosphate dehydrogenase and aldolase were partially inhibited and phosphohexokinase was little affected in both cases.
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PMID:The inhibition of streptococci by lactoperoxidase, thiocyanate and hydrogen peroxide. The oxidation of thiocyanate and the nature of the inhibitory compound. 533 6

The electrophoretic mobility and activity of NADH-methemoglobin reductase in erythrocytes of patients with hereditary methemoglobinemia, obligatory heterozygotes, and normal subjects were examined. Six distinct electrophoretic variants were found in studies of erythrocytes from members of ten different families. Five variants (Boston Slow, Duarte, Princeton, Puerto Rico, and California) were associated with significant methemoglobinemia and moderate to marked decreases in enzymic activity. Precise correlations between levels of NADH-methemoglobin reductase activity, electrophoretic mobility, and clinical severity of methemoglobinemia, however, could not be drawn. One variant (Boston Fast) was associated with almost normal activity and very minimal methemoglobinemia. Nine members from three generations of two Italian families were found to have two bands with NADH-methemoglobin reductase activity in their erythrocytes, one with normal mobility and one with a mobility identical with that of Boston Fast. No functional or clinical impairment could be attributed to this abnormality. The observations made in this investigation were consistent with an autosomal recessive mode of inheritance of multiple alleles for NADH-methemoglobin reductase. As has been shown to be true for hemoglobin and glucose-6-phosphate dehydrogenase, multiple aberrations in the NADH-methemoglobin reductase of human erythrocytes apparently exist, some with and some without functional consequences. Two bands with NADPH-methemoglobin reductase activity with electrophoretic mobilities distinct from those of the NADH-methemoglobin reductase were found in human erythrocytes. These bands were normal in hemolysates of erythrocytes from patients with hereditary methemoglobinemia, but were absent from the hemolysate of erythrocytes deficient in NADPH-methemoglobin reductase activity. These latter erythrocytes, however, contained normal concentrations of methemoglobin and had a normal ability to reduce methemoglobin in vitro. These observations were most consistent with the thesis that the NADH-methemoglobin reductase, distinct from any NADPH-methemoglobin reductase, was the major system responsible for the reduction of methemoglobin to hemoglobin in human erythrocytes.
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PMID:Electrophoretic and functional variants of NADH-methemoglobin reductase in hereditary methemoglobinemia. 554 74

1. Aerobically grown yeast having a high activity of glyoxylate-cycle, citric acid-cycle and electron-transport enzymes was transferred to a medium containing 10% glucose. After a lag phase of 30min. the yeast grew exponentially with a mean generation time of 94min. 2. The enzymes malate dehydrogenase, isocitrate lyase, succinate-cytochrome c oxidoreductase and NADH-cytochrome c oxidoreductase lost 45%, 17%, 27% and 46% of their activity respectively during the lag phase. 3. When growth commenced pyruvate kinase, pyruvate decarboxylase, alcohol dehydrogenase, glutamate dehydrogenase (NADP(+)-linked) and NADPH-cytochrome c oxidoreductase increased in activity, whereas aconitase, isocitrate dehydrogenase (NAD(+)- and NADP(+)-linked), alpha-oxoglutarate dehydrogenase, fumarase, malate dehydrogenase, succinate-cytochrome c oxidoreductase, NADH-cytochrome c oxidoreductase, NADH oxidase, NADPH oxidase, cytochrome c oxidase, glutamate dehydrogenase (NAD(+)-linked), glutamate-oxaloacetate transaminase, isocitrate lyase and glucose 6-phosphate dehydrogenase decreased. 4. During the early stages of growth the loss of activity of aconitase, alpha-oxoglutarate dehydrogenase, fumarase and glucose 6-phosphate dehydrogenase could be accounted for by dilution by cell division. The lower rate of loss of activity of isocitrate dehydrogenase (NAD(+)- and NADP(+)-linked), glutamate dehydrogenase (NAD(+)-linked), glutamate-oxaloacetate transaminase, NADPH oxidase and cytochrome c oxidase implies their continued synthesis, whereas the higher rate of loss of activity of malate dehydrogenase, isocitrate lyase, succinate-cytochrome c oxidoreductase, NADH-cytochrome c oxidoreductase and NADH oxidase means that these enzymes were actively removed. 5. The mechanisms of selective removal of enzyme activity and the control of the residual metabolic pathways are discussed.
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PMID:The kinetics of enzyme changes in yeast under conditions that cause the loss of mitochondria. 566 Jun 27

The enzymatic reduction of naltrexone proceeds more rapidly for formation of 6 alpha- than 6 beta-naltrexol in vitro in the guinea pig hepatic cytosol preparation. This paper describes the effect shown by addition of morphine to this formation; stimulation of the stereo-selective formation of 6 alpha-naltrexol. The enzyme activity for formation of 6 alpha-naltrexol was greatest in the 50--70% ammonium sulfate-precipitated fraction, whereas that for 6 beta-naltrexol formation peaked in the 40--60% fraction. When the 60--70% ammonium sulfate fraction was incubated with naltrexone, it was found that the Vmax was greatest for formation of 6 alpha-naltrexol when NADPH was added as the cofactor, less with the glucose-6-phosphate dehydrogenase NADPH-generating system, and least with NADH. When 10 mM morphine was added, the stimulation of 6 alpha-naltrexol formation occurred when either NADPH or NADH was added as cofactor. Inasmuch as enzyme activity with NADH in the absence of morphine was low, the relative stimulation by morphine was greater for the NADH than for the NADPH system. Also, when both NADPH and NADH were added in the same assay mixture, the predominant effect appeared to be manifested by the NADH system. Experiments in vivo indicated that coadministration of morphine intravenously with 3H-naltrexone did not produce stimulation of 6 alpha-naltrexol formation as measured in either bile or urine. On the other hand, the previous results on stimulation of 6 alpha-naloxol formation from naloxone were confirmed in vivo.
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PMID:The stimulatory effect of morphine on reduction of naltrexone to 6 alpha-naltrexol in the guinea pig. 610 24

The quantitative assay of hexokinase (HK), phosphorylase, phosphofructokinase (PFK), glucose 6-phosphate dehydrogenase (G-6-PDH), glycerol 3-phosphate dehydrogenase (G-3 PDH) and lactate dehydrogenase (LDH) revealed that coxal muscles compared to hepatopancreas contained higher activities of all the enzymes investigated. It appears that the coxal muscles of the premolt field crab has carbohydrate-based fuel economy. The hepatopancreas is a rich source of lipid and very poor source of glycogen. The activity of G-6-PDH is moderately high in the hepatopancreas. It seems that in this lipogenic tissue conversion of G-6-P to triose phosphate occurs predominately via pentose-phosphate pathway thus generating NADPH for lipogenesis. The relative G-3PDH ad LDH activities in hepatopancreas and coxal muscles led us to believe that the reconversion of NAD from NADH in hepatopancreas nd muscle flexor is effected by glycerol 3-phosphate shuttle, whereas in muscle extensor it is achieved by both G-3PDH and LDH activities.
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PMID:Glycolytic enzymes in the premolt field crab Paratelphusa hydrodromus (Milne-Edwards) (Crustacea). 619 88

Oral administration of manganese chloride (25 mg/kg b. w. daily) to monkeys for a period of 18 months produced congestion and marked increase in weight of testis. Histopathologic examination revealed interstitial oedema and degeneration of seminiferous tubules. Activities of succinic dehydrogenase, glucose-6-phosphate dehydrogenase and acid phosphatase were significantly inhibited whereas NADH-diaphorase and alkaline phosphatase activities showed only slight inhibition in seminiferous tubules of treated monkeys. It was concluded that chronic exposure to manganese does not produce sever degenerative changes in the testis earlier than metal induced encephalopathy in primates.
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PMID:Manganese induced testicular changes in monkeys. 624 33

Mitochondrial enzymes in rat livers or intestines were investigated in experimental models with ethanol- or other hepatotoxic agent-induced liver injuries and extrahepatic cholestasis. In clinical experiment, activities of mitochondrial GOT (mGOT) and ornithine carbasmyl transferase (OCT) were examined in alcoholisms and patients with other various liver diseases. Results obtained are as follows; 1) The activities of OCT and mGOT were increased particularly at onset of acute hepatitis, in chronic active hepatitis and intrahepatic cholestasis, showing that mitochondria were injured strikingly in these diseases. The activities in alcoholics were not so great, however mGOT/total-GOT ratio was increased in level than in other diseases. 2) Changes in mitochondrial enzymes of rat liver treated with ethanol were too varied to catch the actual tendency in this pathologic state. 3) Administration of galactosamine, carbon tetrachloride, or alpha-naphthyl isothiocyanate (ANIT) caused a significant fall in activities of succinate cytochrome C reductase and OCT, along with increase in serum activity of OCT, indicating severe mitochondrial injury with these drugs. Extrahepatic cholestasis following bile duct ligation showed the same changes of mitochondrial enzymes in liver tissue and serum. 4) These data indicate that observation of activities of serum OCT, mGOT, along with mGOT/total-GOT ratio are useful for estimation of mitochondrial damage in extra- and intra-hepatic cholestasis, and acute or chronic active hepatitis. The changes in alcoholic fatty liver was not so subtle as compared with other liver diseases. 5) It is surmized that smooth endoplasmic reticulum was increased in content and pentose phosphate shunt was inhibited by chronic ethanol treatment, estimating from increased activities of NADH-ferricyanide reductase and gamma-glutamyl transpeptidase, and decreased activity of glucose-6-phosphate dehydrogenase. 6) The changes in hepatic enzymes with ethanol treatment were paralleled with those of intestinal ones, indicating that metabolic changes in intestine contribute someway in the formation of alcoholic fatty liver. 7) Chronic ethanol treatment induced lowered active transport in intestinal mucosa, which indicates inhibition in absorption of various nutrients by ethanol.
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PMID:[Experimental and clinical studies on enzymes of mitochondria in various liver diseases; with special reference to alcoholic liver disease (author's transl)]. 625 Sep 59

A simple screening procedure for the detection of adenilate kinase (AK), hexokinase (Hx) or glucose-6-phosphate dehydrogenase (G6PD) deficiencies in blood, is described. It consists of two assays : in the first, the ATP formed by blood AK is coupled to Hx and G6PD, and in the second, the glucose-6-phosphate formed by blood Hx is coupled to G6PD. The enzyme activities are visually estimated by the reduction of NADP+ (non-fluorescent) to NADH (fluorescent). The appearance of fluorescence in the first assay indicates that the three enzyme activities are present. The absence of fluorescence could be due to the deficiency of any one of the three enzymes; in this case the second assay used in combination with the Beutler's screening test for G6PD permits the detection of the specific enzymatic deficiency.
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PMID:A simple screening procedure for adenylate kinase, hexokinase and glucose-6-phosphate dehydrogenase deficiencies. 625 22

Escherichia coli was grown in chemostat culture under glycerol-limited and ammonium-limited conditions at growth rates between 0.1 and 0.5 h-1. At steady state, the concentrations of cyclic AMP and cyclic GMP and the activities of four constitutive enzymes (glucose-6-phosphate dehydrogenase, isocitrate dehydrogenase, NADH oxidase and cyclic phosphodiesterase) were determined in the organism. Addition of exogenous cyclic AMP, cyclic GMP or phencyclidine perturbed the steady state and caused inhibition or stimulation of synthesis of phosphodiesterase and isocitrate dehydrogenase. A novel hypothesis is proposed to account for the ability of bacteria to regulate the synthesis of constitutive enzymes with cyclic nucleotides and possibly other small molecules.
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PMID:Cyclic AMP and cyclic GMP control of synthesis of constitutive enzymes in Escherichia coli. 628 44


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