Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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)

The thioredoxin/thioredoxin reductase system has been studied as regenerative machinery for proteins inactivated by oxidative stress in vitro and in cultured endothelial cells. Mammalian glyceraldehyde-3-phosphate dehydrogenase was used as the main model enzyme for monitoring the oxidative damage and the regeneration. Thioredoxin and its reductase purified from bovine liver were used as the regenerating system. The physiological concentrations (2-14 microM) of reduced thioredoxin, with 0.125 microM thioredoxin reductase and 0.25 mM NADPH, regenerated H2O2-inactivated glyceraldehyde-3-phosphate dehydrogenase and other mammalian enzymes almost completely within 20 min at 37 degrees C. Although the treatment of endothelial cells with 0.2-12 mM H2O2 for 5 min resulted in a marked decrease in the activity of glyceraldehyde-3-phosphate dehydrogenase, it had no effect on the activities of thioredoxin and thioredoxin reductase. Essentially all of the thioredoxin in endothelial cells at control state was in the reduced form and 70-85% remained in the reduced form even after the H2O2 treatment. The inactivated glyceraldehyde-3-phosphate dehydrogenase in a cell lysate prepared from the H2O2-treated endothelial cells was regenerated by incubating the lysate with 3 mM NADPH at 37 degrees C and the antiserum raised against bovine liver thioredoxin inhibited the regeneration. The inhibition of thioredoxin reductase activity by 13-cis-retinoic acid resulted in a decrease in the regeneration of glyceraldehyde-3-phosphate dehydrogenase in the H2O2-treated endothelial cells. The present findings provide evidence that thioredoxin is involved in the regeneration of proteins inactivated by oxidative stress in endothelial cells.
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PMID:Thioredoxin regenerates proteins inactivated by oxidative stress in endothelial cells. 142 98

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

Thioredoxin, a dithiol polypeptide, has been examined as a potential contributor to the recovery of lens epithelial cells from oxidative insult. It is reported that Escherichia coli thioredoxin can (a) effectively reduce lens-soluble protein disulfide bonds generated by H2O2, (b) restore to its initial activity H2O2-inactivated glyceraldehyde-3-phosphate dehydrogenase, (c) act as an effective source of reducing potential for lens methionine sulfoxide peptide reductase, and (d) act as a free radical quencher based on studies with a stable free radical system generated by ascorbic acid and 2,6-dimethoxy-p-benzoquinone. Thioredoxin is much more effective than dithiothreitol in restoring glyceraldehyde-3-phosphate dehydrogenase activity and as a cofactor for methionine sulfoxide peptide reductase. Upon incubation with epithelial cells, thioredoxin can be observed in the cell using rocket immunoelectrophoresis. These cells recover from H2O2 insult more rapidly than control cell preparations based upon 1) analyses of plasma membrane-related activities: leucine and 86Rb uptake and 2) analyses of parameters primarily related to the internal cell metabolism: ATP concentration and glyceraldehyde-3-phosphate dehydrogenase activity. Analysis of thioredoxin in cell preparations indicates that only about 9% is in the reduced state implying a low effective concentration of the polypeptide. The experiments suggest that low levels of thioredoxin may significantly increase the ability of lens epithelial cells to recover from exposure to H2O2.
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PMID:The effect of H2O2 upon thioredoxin-enriched lens epithelial cells. 283 16

A second thioredoxin, distinct from the one reported by Meng and Hogenkamp in 1981 (J. Biol. Chem. 256, 9174-9182), has been purified to homogeneity from an Escherichia coli strain containing a plasmid encoding a Corynebacterium nephridii thioredoxin. Thioredoxin genes from C. nephridii were cloned into the plasmid pUC13 and transformants were identified by complementation of a thioredoxin negative (trxA-) E. coli strain. The abilities of the transformants to support the growth of several phages suggested that more than one thioredoxin had been expressed [Lim et al. (1987) J. Biol. Chem. 262, 12114-12119]. In this paper we present the purification and characterization of one of these thioredoxins. The new thioredoxin from C. nephridii, designated thioredoxin C-2, is a heat-stable protein containing three cysteine residues/molecule. It serves as a substrate for C. nephridii thioredoxin reductase and E. coli and Lactobacillus leichmannii ribonucleotide reductases. Thioredoxin C-2 catalyzes the reduction of insulin disulfides by dithiothreitol or by NADPH and thioredoxin reductase and is a hydrogen donor for the methionine sulfoxide reductase of E. coli. Spinach malate dehydrogenase (NADP+) and phosphoribulokinase are activated by this thioredoxin while glyceraldehyde-3-phosphate dehydrogenase (NADP+) is not. Like the thioredoxin first isolated from C. nephridii, this new thioredoxin is not a reducing substrate for the C. nephridii ribonucleotide reductase. The complete primary sequence of this second thioredoxin has been determined. The amino acid sequence shows a high degree of similarity with other thioredoxins. Surprisingly, in contrast to the other sequences, this new thioredoxin contains the tetrapeptide -Cys-Ala-Pro-Cys- at the active site. With the exception of the T4 thioredoxin, this is the first example of a thioredoxin that does not have the sequence -Cys-Gly-Pro-Cys-. Our results suggest that, like plant cells, bacterial cells may utilize more than one thioredoxin.
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PMID:Purification, characterization and revised amino acid sequence of a second thioredoxin from Corynebacterium nephridii. 291 72

A homogeneous multimeric protein isolated from the green alga, Scenedesmus obliquus, has both latent phosphoribulokinase activity and glyceraldehyde-3-phosphate dehydrogenase activity. The glyceraldehyde-3-phosphate dehydrogenase was active with both NADPH and NADH, but predominantly with NADH. Incubation with 20 mM dithiothreitol and 1 mM NADPH promoted the coactivation of phosphoribulokinase and NADPH-dependent glyceraldehyde-3-phosphate dehydrogenase, accompanied by a decrease in the glyceraldehyde-3-phosphate dehydrogenase activity linked to NADH. The multimeric enzyme had a Mr of 560,000 and was of apparent subunit composition 8G6R. R represents a subunit of Mr 42,000 conferring phosphoribulokinase activity and G a subunit of 39,000 responsible for the glyceraldehyde-3-phosphate dehydrogenase activity. On SDS-PAGE the Mr-42,000 subunit comigrates with the subunit of the active form of phosphoribulokinase whereas that of Mr-39,000 corresponds to that of NADPH-dependent glyceraldehyde-3-phosphate dehydrogenase. The multimeric enzyme had a S20,W of 14.2 S. Following activation with dithiothreitol and NADPH, sedimenting boundaries of 7.4 S and 4.4 S were formed due to the depolymerization of the multimeric protein to NADPH-dependent glyceraldehyde-3-phosphate dehydrogenase (4G) and active phosphoribulokinase (2R). It has been possible to isolate these two enzymes from the activated preparation by DEAE-cellulose chromatography. Prolonged activation of the multimeric protein by dithiothreitol in the absence of nucleotide produced a single sedimenting boundary of 4.6 S, representing a mixture of the active form of phosphoribulokinase and an inactive dimeric form of glyceraldehyde-3-phosphate dehydrogenase. Algal thioredoxin, in the presence of 1 mM dithiothreitol and 1 mM NADPH, stimulated the depolymerization of the multimeric protein with resulting coactivation of phosphoribulokinase and NADPH-dependent glyceraldehyde-3-phosphate dehydrogenase. Light-induced depolymerization of the multimeric protein, mediated by reduced thioredoxin, is postulated as the mechanism of light activation in vivo. Consistent with such a postulate is the presence of high concentrations of the active forms of phosphoribulokinase and NADPH-dependent glyceraldehyde-3-phosphate dehydrogenase in extracts from photoheterotrophically grown algae. By contrast, in extracts from the dark-grown algae the multimeric enzyme predominates.
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PMID:Properties of a multimeric protein complex from chloroplasts possessing potential activities of NADPH-dependent glyceraldehyde-3-phosphate dehydrogenase and phosphoribulokinase. 302 12

The thioredoxin peptide Trp-Cys-Gly-Pro-Cys-Lys, which contains the redox active dithiol, was found to be reduced by lipoamide in a coupled reaction with lipoamide dehydrogenase and NADH. The reduced peptide in turn was shown to reduce insulin, oxidized lens protein and glyceraldehyde-3-phosphate dehydrogenase. While the peptide is not as effective a catalyst for utilizing pyridine nucleotides to reduce protein disulfides as thioredoxin, it offers a system which may be developed to provide more efficient disulfide reduction. This is particularly relevant since no thioredoxin peptides have been found to be active with thioredoxin reductase.
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PMID:Thioredoxin fragment 31-36 is reduced by dihydrolipoamide and reduces oxidized protein. 312 52

Kinetic analysis of glyceraldehyde-3-phosphate dehydrogenase showed that the enhancement of the NADP-linked activity by specific chloroplast modulators is a concerted process; either a selected second metabolite or the couple dithiothreitol/thioredoxin-f lowers the concentration of primary modulators (ATP, NADPH, inorganic phosphate, 1,3-diphosphoglycerate) required for maximal stimulation (A0.5). Organic solvents also stimulate NADP-glyceraldehyde-3-phosphate dehydrogenase in the absence of any modulator; the concentration for the highest specific activity correlates inversely with the respective octanol-water partition coefficient. On the other hand, alcohols also enhance enzyme activity by lowering the A0.5 for primary modulators. Another compound--spermine--inhibits both the ATP- and the inorganic phosphate-mediated activation, but it does not influence the NADPH-induced process.
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PMID:Activation of spinach chloroplast NADP-linked glyceraldehyde-3-phosphate dehydrogenase by concerted hysteresis. 396 15

Protein disulfide isomerase (PDI) alkylated at thiols of the thioredoxin-like -CHC- active sites is devoid of isomerase activity, but its chaperone-like activity to increase the reactivation yield and prevent the aggregation of guanidine hydrochloride-denatured D-glyceraldehyde-3-phosphate dehydrogenase upon dilution is unimpaired. A peptide of 28 amino acids markedly inhibits both the enzyme and the chaperone activities of PDI. The above results indicate that the -CGHC- active site is necessary for the isomerase activity but not required for the chaperone activity of PDI, whereas the peptide binding site is essential for both activities.
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PMID:Independence of the chaperone activity of protein disulfide isomerase from its thioredoxin-like active site. 761

Spinach chloroplast NAD(P)-glyceraldehyde-3-phosphate dehydrogenase (NAD(P)-GAPDH; EC, 1.2.1.13) was purified as the 600-kDa oligomer of low specific activity. Incubation of the enzyme with either a reductant or a 1,3-bisphosphoglycerate (1,3bisPGA) generating system, but most effectively with both, resulted in an increase of the apparent NADPH-dependent activity. Only the 1,3bisPGA treatment caused dissociation and yielded the 150-kDa heterotetramer (A2B2). The higher activity of the tetramer is largely due to a decreased KM value for the substrate 1,3bisPGA. Reductive treatment alone does not dissociate the enzyme. Reduction was equally effective with glutathione as with dithiothreitol or with reduced thioredoxin f. The concentration of 1,3bisPGA required to obtain 50% activity (K alpha) was 19.5 +/- 4.1 microM for the untreated enzyme and 2.0 +/- 1.4 microM for the thiol-pretreated enzyme. Thus, in vitro 1,3bisPGA, alone or--at much lower concentrations--together with a reductant can activate (and dissociate) NAD(P)-GAPDH. The enzyme exhibits similar K alpha values in its reduced and its oxidized form for ATP (1-2 mM), NADP (50-200 microM), and NADPH (0.3-0.5 mM) as positive effectors, but these effectors do not lead to any activation when present together with 0.14 mM NAD. Only 1,3bisPGA retained its characteristic effect in the presence of NAD. The dissociated enzyme reaggregates upon removal of the positive effectors. From these results it is concluded (i) that the role of the reduction of the NAD(P)-GAPDH in vivo is to increase its sensitivity toward the activator 1,3bisPGA and (ii) that the actual activation (and aggregation) state of the enzyme in chloroplasts in the light is regulated by the concentration of 1,3bisPGA as activator in the stroma and its actual activity by the availability of 1,3bisPGA as substrate.
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PMID:Reductive modification and nonreductive activation of purified spinach chloroplast NADP-dependent glyceraldehyde-3-phosphate dehydrogenase. 855 10

A bienzyme complex made up of phosphoribulokinase and glyceraldehyde-3-phosphate dehydrogenase has been isolated and purified from chloroplasts of Chlamydomonas reinhardtii. The complex contains four phosphoribulokinase and eight glyceraldehyde-3-phosphate dehydrogenase polypeptide chains. As phosphoribulokinase is dimeric and glyceraldehyde-3-phosphate dehydrogenase tetrameric, it is concluded that the complex comprises two phosphoribulokinase and two glyceraldehyde-3-phosphate dehydrogenase molecules. Its overall molecular mass is 460 kDa, which is in excellent agreement with its stoichiometry. Moreover, owing to the nature of the two enzymes, this complex must catalyse two nonconsecutive reactions. The bienzyme complex tended to spontaneously dissociate into the free enzymes upon dilution. This dissociation process was considerably promoted by reducing agents such as dithiothreitol or reduced thioredoxin. The kinetics of the dissociation process induced by dithiothreitol or reduced thioredoxin were paralleled by an increase of activity of phosphoribulokinase. The dissociation of the complex was reversible. If oxidized phosphoribulokinase and glyceraldehyde-3-phosphate dehydrogenase were mixed, a certain amount of the complex was formed. The reconstituted complex displayed properties that were indistinguishable from those of the native complex extracted from chloroplasts of Chlamydomonas reinhardtii. These results suggest that the concentration of the complex in vivo must vary depending on the light intensity.
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PMID:Memory and imprinting effects in multienzyme complexes--I. Isolation, dissociation, and reassociation of a phosphoribulokinase-glyceraldehyde-3-phosphate dehydrogenase complex from Chlamydomonas reinhardtii chloroplasts. 921 Apr 68


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