Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.2.1.13 (glyceraldehyde-3-phosphate dehydrogenase)
 6,511 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

By combining our knowledge of the crystal structure of the glycolytic NAD-dependent glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and the sequence of the photosynthetic NADP-dependent GAPDH of the chloroplast, two particular amino acid residues were predicted as the principal determinants of differing coenzyme specificity. By use of site-directed mutagenesis, the amino acids Leu 187 and Pro 188 of GAPDH from Bacillus stearothermophilus have been replaced with Ala 187 and Ser 188, which occur in the sequence from the chloroplast enzyme. The resulting mutant was shown to be catalytically active not only with its natural coenzyme NAD but also with NADP, thus confirming the initial hypothesis. This approach has not only enabled us to alter the coenzyme specificity by minimal amino acid changes but also revealed factors that control the relative affinity of the enzyme for NAD and NADP.
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PMID:Probing the coenzyme specificity of glyceraldehyde-3-phosphate dehydrogenases by site-directed mutagenesis. 222 64

We utilized differential plaque hybridization to identify three cDNA clones for transcripts which increase in abundance during the salinity-induced transition from C3 photosynthesis to crassulacean acid metabolism (CAM) in Mesembryanthemum crystallinum. Although there are differences in the abundance of these transcripts in unstressed tissue, steady-state levels of all three increased within 30 h following irrigation with 0.5 M NaCl. One cDNA encodes the cytosolic form of glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating) (NAD-GAPDH], an enzyme involved in the production of phosphoenolpyruvate for CO2 fixation at night and the conversion of pyruvate to storage carbohydrate during the day. Coding region and 3'-noncoding sequence probes were used to examine the expression of NAD-GAPDH transcripts in leaf and root tissue. We show that the gene encoding the NAD-GAPDH cDNA is expressed in both leaf and root tissue during C3 photosynthesis and CAM. NAD-GAPDH transcript levels increase rapidly in leaf (but not in root) tissue during the transition to CAM. Our data indicate that the predominant NAD-GAPDH transcript expressed during C3 photosynthesis and CAM is encoded by a single gene in M crystallinum. These results imply that the transition to CAM in some cases involves an upward readjustment in the level of a gene product expressed during C3 photosynthesis, rather than the expression of a CAM-specific isoform with unique regulatory or kinetic properties.
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PMID:Increased expression of a gene coding for NAD:glyceraldehyde-3-phosphate dehydrogenase during the transition from C3 photosynthesis to crassulacean acid metabolism in Mesembryanthemum crystallinum. 230 58

Neutral salts enhanced the specific activity of chloroplast NADP-glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate:NADP+ oxidoreductase (phosphorylating), EC 1.2.1.13) from spinach leaves. The ordering of the respective anions, according to the concentration for maximal stimulation, yielded the lyotropic (Hofmeister) series [SCN- (0.05 M), ClO-4 (0.08 M), Cl3CCO-2 (0.24 M), I- (0.35 M), Br- (0.6 M), Cl- (1.0 M)]; the more chaotropic the anion the less its concentration for maximal activation. Neither the NAD-linked activity of the chloroplast enzyme nor glyceraldehyde-3-phosphate dehydrogenases originating from cyanobacteria and rabbit muscle were stimulated by neutral salts. Chaotropic anions also enhanced the catalytic capacity of the chloroplast enzyme at concentrations lower than those required for the activation process. In the presence of 0.12 M NaBr the rate of catalysis was maximum whereas the highest conversion from the inactive to an active form was observed at 0.6 M NaBr. On the other hand, nonstimulatory concentrations of chaotropic anions lowered the concentration of ATP, Pi, and NADPH required for maximum stimulation of the specific activity (concerted hysteresis). On the basis that the enhancement of NADP-glyceraldehyde-3-phosphate dehydrogenase (and other chloroplast enzymes) by chaotropic anions paralleled the effect of organic solvents and reduced thioredoxin, it appeared that the modification of hydrophobic (intramolecular) interactions participates in the mechanism of light-mediated regulation.
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PMID:Modulation of spinach chloroplast NADP-glyceraldehyde-3-phosphate dehydrogenase by chaotropic anions. 233 56

The inactivation of bovine heart glyceraldehyde-3-phosphate dehydrogenase by phosphatidylinositol (PI) and phosphatidylserine (PS) in the form of liposomes was investigated in the presence and absence of NAD excess. In the absence of NAD, the enzyme activity decreased to about 50% of its initial value at 0.6 mM PI and 0.8 mM PS (lipid-to-protein molar ratio 600 and 800, respectively). In the same lipid concentration range almost full regainment of the activity was observed in the presence of 80 microM NAD. It was shown that the excess of NAD protects the enzyme against conformational change induced by the phospholipids. Centrifugation experiments showed that both PI and PS bind significant amounts of NAD.
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PMID:Effect of NAD coenzyme on the inactivation of glyceraldehyde-3-phosphate dehydrogenase by anionic phospholipids. 236 66

Stereospecificities are reported for seven dehydrogenases from Acholeplasma laidlawii, an organism from an evolutionarily distinct branch of life which has not previously been studied from a stereochemical point of view. Three of the activities examined (alcohol dehydrogenase, lactate dehydrogenase, and alanine dehydrogenase) catalyze the transfer of the pro-R (A) hydrogen from NADH. Four other activities (3-hydroxy-3-methylglutaryl-CoA reductase, glyceraldehyde-3-phosphate dehydrogenase, glucose-6-phosphate dehydrogenase, and NADH oxidase) catalyze the transfer of the pro-S (B) hydrogen from NAD(P)H. The stereospecificity of hydroxymethylglutaryl-CoA reductase is notable because it is the opposite of that of hydroxymethylglutaryl-CoA reductases from yeast and rat. These data are used to derive the simplest historical model capable of explaining available experimental facts.
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PMID:The stereospecificities of seven dehydrogenases from Acholeplasma laidlawii. The simplest historical model that explains dehydrogenase stereospecificity. 236 93

The interaction of acrylamide with rabbit muscle glyceraldehyde-3-phosphate dehydrogenase (GPDH) has been investigated in Tris buffer, pH 7.5. When GPDH containing about 1 mol NAD per mol of tetramer is incubated with acrylamide (0.01-0.1 M), the tryptophan emission of GPDH, initially quenched by acrylamide, slowly increases to a value exceeding that recorded before the addition of acrylamide. This effect is not observed in apoenzyme solutions, indicating that the enhancement of fluorescence results from the dissociation of some NAD from the acrylamide treated GPDH. Acrylamide inactivates GPDH but 1 mM NAD protects the enzyme from inactivation. The addition of acrylamide to GPDH, labeled with fluorescein-5-isothiocyanate (GPDH-FITC) increases the fluorescence and decreases the polarization of fluorescein. The fluorescent sulfhydryl reagent N-iodoacetyl-N'-(5-sulfo-1-naphthyl)ethylenediamine induces similar changes in the fluorescence properties of GPDH-FITC. This reagent, however, fails to react with GPDH preincubated with acrylamide and the titration of acrylamide treated GPDH with the sulfhydryl reagent 5,5'-dithiobis(2-nitrobenzoic acid) indicates the loss of up to 7 cysteine residues per tetramer. Acrylamide also decreases the heat stability of GPDH. Altogether, the data indicate that acrylamide covalently reacts with the active site cysteine residues of GPDH and subsequently induces a conformational change in the enzyme.
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PMID:The interaction of acrylamide with glyceraldehyde-3-phosphate dehydrogenase. Structural modifications in the enzyme studied by fluorescence techniques. 236 67

A major 38-kDa protein associated with bovine rod outer segment plasma membranes, but not disk membranes, has been identified as glyceraldehyde-3-phosphate dehydrogenase on the basis of its N-terminal sequence and specific enzyme activity. This enzyme was extracted from lysed rod outer segments or isolated rod outer segment plasma membrane with 0.15 M NaCl and purified to homogeneity by affinity chromatography on a NAD(+)-agarose column. A specific activity of 90-100 units/mg of protein is within the range of activity obtained for glyceraldehyde-3-phosphate dehydrogenase isolated from other mammalian cells. Enzyme activity measurements indicate that this enzyme makes up approximately 2% of the total rod outer segment protein and over 11% of the plasma membrane protein. Protease digestion and binding studies on purified rod outer segment plasma and disk membranes suggest that glyceraldehyde-3-phosphate dehydrogenase reversibly interacts with a protease-sensitive plasma membrane-specific protein of rod outer segments. The finding that glyceraldehyde-3-phosphate dehydrogenase is present in large quantities in rod outer segments suggests that at least some of the energy required for the synthesis of ATP and GTP for phototransduction and other processes of the outer segment is derived from glycolysis which takes place within this organelle.
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PMID:Glyceraldehyde-3-phosphate dehydrogenase is a major protein associated with the plasma membrane of retinal photoreceptor outer segments. 237 95

H2O2 concentrations only slightly higher than normal physiological levels found in the lens and aqueous fluid produce a significant number of DNA single-strand breaks in lens epithelial cell cultures. In this investigation, the repair of DNA damaged by short-term, H2O2-induced oxidation was examined in bovine lens epithelial cell cultures. Repair was rapidly initiated and was almost completed in 30 min. A drop in NAD concentration was associated with the DNA damage. 3-Aminobenzamide inhibition of poly(ADP-ribose) polymerase, an enzyme believed to be stimulated by DNA oxidation and involved in DNA repair, prevented the loss of NAD. In contrast, a similar drop in ATP concentration was only slightly lessened by the presence of this inhibitor. Inhibition of the polymerase by 3-aminobenzamide primarily affected only the early recovery period. Overall, recovery occurred almost as effectively in the presence of the inhibitor as in its absence. Preincubation of lens cultures with o-phenanthroline, an iron chelator, prevented the drop in NAD levels associated with DNA damage. Since a hydroxyl radical is produced from H2O2 by a Fenton type reaction, this result supports the concept that the H2O2-induced oxidation of DNA is caused by hydroxyl radical. In contrast, peroxide-induced loss of activity of a cytosolic enzyme, glyceraldehyde-3-phosphate dehydrogenase, was unaffected by the presence of o-phenanthroline, suggesting direct H2O2 oxidation of this enzyme. The results of these experiments suggest that lens epithelium contains enzymes that rapidly repair single-strand DNA breaks induced by H2O2 insult.
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PMID:Repair of H2O2-induced DNA damage in bovine lens epithelial cell cultures. 250 31

Several enzymes active in the presence of NAD with acetaldehyde and propionaldehyde have been purified from human brain and characterized. The enzymes have been identified as aldehyde dehydrogenase (EC 1.2.1.3), NAD-linked succinic semialdehyde dehydrogenase (EC 1.2.1.24), and glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12). Glyceraldehyde-3-phosphate dehydrogenase is extremely heterogeneous with some isozymes active with acetaldehyde, others inactive. The cytoplasmic enzyme, which is the classical glyceraldehyde-3-phosphate dehydrogenase, is inactive with acetaldehyde as substrate; the isozymes that are active with short chain aliphatic aldehydes are localized in the mitochondrial fraction. Properties of glyceraldehyde-3-phosphate dehydrogenase isozymes with respect to short chain aliphatic aldehydes and inhibition by disulfiram are described. Their Km values for acetaldehyde range from 300 to 2000 microM. All glyceraldehyde-3-phosphate dehydrogenases that are active with acetaldehyde are easily inactivated by low concentrations of disulfiram. In all cases activity regain can be obtained with 2-mercaptoethanol; in the case of two glyceraldehyde-3-phosphate isozymes (E8.5 and 9.0), activity can also be regained with cysteine and with glutathione; activity of E6.6 and E6.8 glyceraldehyde-3-phosphate dehydrogenases could not be regained with 33 microM cysteine or glutathione. Succinic semialdehyde dehydrogenase and aldehyde dehydrogenase (EC 1.2.1.3) were also inhibited by disulfiram; their activity could be regained with 2-mercaptoethanol but not with 33 microM cysteine or glutathione. Comparison of human brain succinic semialdehyde dehydrogenase and aldehyde dehydrogenase with glyceraldehyde-3-phosphate dehydrogenase shows that the activity with short chain aldehydes is not unique to aldehyde dehydrogenase; neither is sensitivity to disulfiram; activity with 3,4-dihydroxyphenylacetaldehyde appears to be a unique property of aldehyde dehydrogenase (EC 1.2.1.3).
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PMID:Human brain glyceraldehyde-3-phosphate dehydrogenase, succinic semialdehyde dehydrogenase and aldehyde dehydrogenase isozymes: substrate specificity and sensitivity to disulfiram. 269 Jun 58

The proliferation of in vitro grown Ehrlich ascites tumor cells is inhibited by pyruvate concentrations greater than 2 mM. In the presence of 4-5 mM pyruvate the growth is reduced to about 50%, in the presence of 20 mM to about 5-10%. Viability of the cells is not severely affected. Increase of DNA corresponds to the cell growth. On recultivation in pyruvate free standard medium, growth is nearly normal. Flow cytometric analyses of the proliferation kinetics of the cells in the presence of 20 mM pyruvate revealed a retardation of the passage of all phases of the cell cycle. No phase specific effects could be detected though the S- and G2M-phase are more afflicted than G1. The growth inhibition of EAT cells by pyruvate seems to depend on the presence of glucose. Exogenous pyruvate (greater than 1-2 mM) causes an activation of pyruvate dehydrogenase, a reduction of lactate production from glucose and a stimulation of lipid biosynthesis; the NAD/NADH ratio of the cells is reduced and a rise of glycolytic intermediates beyond glyceraldehyde-3-phosphate dehydrogenase is observed. Maximal activation of pyruvate dehydrogenase by non toxic concentrations of dichloroacetate is also accompanied by an inhibition of cell growth. It is suggested that an increase of glyceraldehyde-3-phosphate level and the changes in the redox state of the cells are of relevance for the inhibition of cell growth by pyruvate. 100-500 microM exogenous glyceraldehyde-3-phosphate strongly inhibited cell growth.
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PMID:Proliferation kinetics and metabolic features of in vitro grown Ehrlich ascites tumor cells in the presence of exogenous pyruvate. 294 14


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