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 spontaneous inactivation of yeast glyceraldehyde-3-phosphate dehydrogenase was found to fit a simple two-state model at pH 8.5 and 25 degrees. The first step is a relatively rapid dissociation of the tetramer to dimers with the equilibrium largely in favor of the tetramer. In the absence of NAD+ the dimer inactivates irreversibly. The apoenzyme is quite stable with a half-life for complete activity loss proportional to the square root of the enzyme concentration. Perturbances of the protein structure (by pH, ionic strength, and specific salts), which have no effect on the tetrameric state of the molecule, result in an alteration of the cooperativity of NAD+ binding, the reactivity of the active-site sulfhydryl group, and the catalytic activity of the enzyme. Covalent modification of two of the four active-site sulfhydryl groups has profound effects on the enzymic activity which are mediated by changes in the subunit interactions. Sedimentation analysis and hybridization studies indicate that the interaction between subunits remains strong after covalent modification. Under normal physiological and equilibrium dialysis conditions the protein is a tetramer. Equilibrium dialysis studies of NAD+ binding to the enzyme at pH 8.5 and 25 degrees reveal a mixed cooperativity pattern. A model consistent with these observations and the observed half-of-the-sites reactivity is that of ligand induced sequential conformational changes which are transferred across strongly interacting subunit domains. Methods for distinguishing negatively cooperative binding patterns from mixtures of denatured enzyme and multiple species are discussed.
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PMID:Subunit interactions in yeast glyceraldehyde-3-phosphate dehydrogenase. 0 55

1. The behaviour and properties of membrane-bound GAPDH of rabbit reticulocytes were investigated. 2. The bound GAPDH is more resistant to inactivation by KCl than the soluble enzyme (allotopy). 3. The bound enzyme is released by electrolytes. This effect does not only depend on the ionic strength but additionally on the kind of ions, pH-value and protein concentration. 4. A comparison of the releasing effect of NAD analogues shows the necessity of the 5'-AMP moiety in the structure of the effector. 5. The represented results demonstrate the specifity of the GAPDH-membrane binding in rabbit reticulocytes.
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PMID:Further characterization of the association of glyceraldehyde-3-phosphate dehydrogenase with reticulocyte membranes. 0 Aug 80

NADH and NADPH-ferredoxin oxidoreductases have been studied in Clostridium acetobutylicum, Cl. tyrobutyricum and Cl. pasteurianum. The study of the distribution and regulation of these enzymatic activities in well-defined culture conditions, reveals that the essential function of NADPH-ferredoxin oxidoreductase is to produce NADPH, while NADH-ferredoxin oxidoreductase can, depending on cellular conditions, produce or oxidize NADH. When these Clostridia use glycolysis, regulation of the NADH-ferredoxin oxidoreductase by acetyl-CoA (obligatory activator of NADH-ferroxin reductase activity) and by NADH (competitive inhibitor of ferredoxin-NAD+ reductase activity) allow the enzymes to function correlatively with glyceraldehyde-3-phosphate dehydrogenase and thus control the levels of NAD+ and NADH in the cell. In Cl. tyrobutyricum and Cl. pasteurianum, the ferredoxin-NADP+ reductase activities are regulated by NAD+ and NADH in accordance with the intracellular concentrations of these coenzymes. In Cl. tyrobutyricum growing on pyruvate/acetate, NADH and NADPH-ferredoxin reductase activities cannot be detected; only the ferredoxin-NAD+ and ferredoxin-NADP+ reductase activities are found. In this Clostridium, regulation of the ferredoxin-NADP+ reductase activity is the same whether it is grown on glucose or pyruvate. Contrary to this, the ferredoxin-NAD+ reductase activity undergoes a drastic change, since NADH no longer controls the enzymatic activity. In this case regulation is no longer necessary, since glyceraldehyde-3-phosphate dehydrogenase does not function.
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PMID:Regulation of the NADH and NADPH-ferredoxin oxidoreductases in clostridia of the butyric group. 0 18

The binding of nicotinamide adenine dinucleotide (NAD+) to yeast glyceraldehyde-3-phosphate dehydrogenase (GPDH) has been studied at pH 6.5 and 8.5, at 5,25, and 40 degrees C, by calorimetry, fluorometry, spectrophotometry, equilibrium dialysis, and flow dialysis. As reported earlier for pH 7.3 (Velick S.F., Baggott, J.P., and Sturtevant, J.M. (1971), Biochemistry 10, 779), the binding is accompanied by enthalpy changes which become rapidly more negative as the temperature increases, with delta Cp = -500 to -750 cal deg-1 (mole of NAD+ bound)-1, and by entropy changes which also, as required by the large negative delta Cp, become rapidly more negative with increasing temperature. The binding data at pH 6.5 can be fitted on the basis of either four identical noninteracting sites, or of four sites showing a small degree of negative cooperativity. The data at pH 8.5, particularly at 40 degrees C, require the introduction of positive cooperativity, as was previously shown by Kirschner et al. (Kirschner, K., Eigen, M., Bittman, R., and Voigt, B. (1966), Proc. Natl. Acad. Sci. U.S.A. 56, 1661), and can be equally well fitted on the basis of a sequential model (Adair, G.S. (1925), J. Biol. Chem. 63, 529) or a concerted model (Monod, J., Wyman, J., and Changeux, J.P. (1965), J. Mol. Biol. 12, 88). It is proposed that the observed thermodynamic changes are largely the result of a hydrophobic effect due to a decrease in the exposure of nonpolar groups to the solvent, and of a tightening of the protein structure when the coenzyme is bound with concomitant decrease in the number of easily excitable internal degrees of freedom.
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PMID:Energetics of the cooperative and noncooperative binding of nicotinamide adenine dinucleotide to yeast glyceraldehyde-3-phosphate dehydrogenase at pH 6.5 and pH 8.5. Equilibrium and calorimetric analysis over a range of temperature. 1 17

NADH-dependent glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.--) of the photosynthetic alga Scenedesmus obliquus is converted to an NADPH specific form by incubation with dithiothreitol. The change in nucleotide specificity is accompanied by a reduction in the molecular weight of the enzyme from 550 000 to 140 000. Prolonged incubation with dithiothreitol results in the further dissociation of the enzyme to an inactive 70 000 dalton species. The 140 000 dalton, NADPH-specific enzyme is stabilized against dissociation and inactivation by the presence of NAD(H) or NADP(H). Optimum stimulation of NADPH-dependent glyceraldehyde-3-phosphate dehydrogenase activity is achieved on incubation of the NADH-specific enzyme with dithiothreitol and NADPH, or dithiothreitol and a 1,3-diphosphoglycerate generating system. The relevance of these observations to in vivo light-induced changes in the nucleotide specificity of the enzyme is discussed.
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PMID:Glyceraldehyde-3-phosphate dehydrogenase of Scenedesmus obliquus. Effects of dithiothreitol and nucleotide on coenzyme specificity. 1 3

The formation of ternary Cu-enzyme-coenzyme complex from cupric ion and D-glyceraldehyde-3-phosphate dehydrogenase holoenzyme results in similar spectral changes as the formation of binary Cu-apoenzyme complex, which indicates that the complex bonds between cupric ion and the holoenzyme, and cupric ion and the apoenzyme are similar. Spectrophotometric titration, chemical modification experiments and inhibition studies with cupric ion gave evidence that cupric ion is selectively bound on Cys-149 residue also in the Cu-GAPD-NAD complex. The charge transfer interaction between the coenzyme and Cu-GAPD, i.e. the difference spectrum of the combination of NAD with Cu-GAPD complex, is different from that of the enzyme-coenzyme complex in the absence of cupric ion. The shape of this "modified enzyme-coenzyme charge transfer spectrum" is influenced by various anions. The difference absorption does not depend on the pH in the range of 5.5 to 9. This indicates that the bound cupric ion abolishes the effect of deprotonation of a functional group in the protein on the charge transfer interaction. It is suggested that this functional group is a histidine imidazole, which activates the Cys-149 thiol group in the native enzyme and binds the metal ion in the cupric complex in a Cys-Cu-His chelate structure.
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PMID:Complex of D-glyceraldehyde-3-phosphate dehydrogenase with Cu2+ ion. The properties of ternary Cu-enzyme-coenzyme complex. 1 25

Glyceraldehyde-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate : NADP+ oxidoreductase (phosphorylating), EC 1.2.1.13) from spinach chloroplasts is a polymeric protein of approx. 600,000 daltons and sodium dodecyl sulphate gel electrophoresis shows that it consists of two subunits of molecular weight 43,000 and 37,000. Comparison of amino acid analyses and tryptic peptide maps indicates that the two subunits have a different primary structure. The native enzyme contains 0.5 mol of NADP+ and 0.5 mol of NAD+ per protomer of 80,000 daltons, no reduced pyridine nucleotides have been detected. Almost complete inactivation is obtained by reaction of two cysteinyl residues per 80,000 daltons with tetrathionate or iodo[14C2]acetic acid; since the same amount of radioactivity is incorporated in the two subunits it is likely that they are both essential for the catalytic activity. Charcoal stripping of native glyceraldehyde-phosphate dehydrogenase produces an apoprotein which still retains most of the enzymatic activity but, unlike the holoenzyme, is gradually inactivated by storage at 4 degrees C and does not react with iodoacetate under the same conditions in which the holoenzyme is completely inactivated.
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PMID:Subunit structure and activity of glyceraldehyde-3-phosphate dehydrogenase from spinach chloroplasts. 2 61

Effects of glucose concentration and anoxia upon the metabolite concentrations and rates of glycolysis and respiration have been investigated in the perfused liver of the fetal guinea pig. In most cases the metabolite concentrations in the perfused liver were similar to those observed in vivo. Between 50 days and term there was a fall in the respiratory rate and in the concentration of ATP and fructose 1,6-diphosphate and an increase in the concentration of glutamate, glycogen and glucose. Reducing the medium glucose concentration from 10 mM to 1 mM or 0.1 mM depressed lactate production and the concentration of most of the phosphorylated intermediates (except 6-phosphogluconate) in the liver of the 50-day fetus. This indicates a fall in glycolytic rate which is not in accord with the known kinetic properties of hexokinase in the fetal liver. Anoxia increased lactate production by, and the concentrations of, the hexose phosphates ADP and AMP in the 50-day to term fetal liver, while the concentration of ribulose 5-phosphate, ATP and some triose phosphates fell. These results are consistent with an activation of glycolysis, particularly at phosphofructokinase and of a reduction in pentose phosphate pathway activity, particularly at 6-phosphogluconate dehydrogenase. The calculated cytosolic NAD+/NADH ratio for the perfused liver was similar to that measured in vivo and evidence is presented to suggest that the dihydroxyacetone phosphate/glycerol 3-phosphate ratio gives a better indication of cytosolic redox than the lactate/pyruvate ratio. The present observations indicate that phosphofructokinase hexokinase and possibly pyruvate kinase control the glycolytic rate and that glyceraldehyde-3-phosphate dehydrogenase is at equilibrium in the perfused liver of the fetal guinea pig.
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PMID:Some effects of glucose concentration and anoxia on glycolysis and metabolite concentrations in the perfused liver of fetal guinea pig. 2 74

1. NAD(P)+-induced changes in the aggregational state of prepurified NADP-linked glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.13) were used to isolate the enzyme from Spinacia oleracea, Pisum sativaum and Hordeum vulgare. Each of the three plant species contains two separate isoenzymes. Isoenzyme 1 (fast moving during conventional electrophoresis) precipitates with the ammonium sulfate fraction 55--70% saturation. It shows two separate subunits in dodecylsulfate gels, which are probably arranged as A2B2 in the native enzyme molecule. Isoenzyme 2 (slow moving during conventional electrophoresis) precipitates with the ammonium sulfate fraction 70--95%. It contains a sigle subunit of the same Mr as subunit A in isoenzyme 1 and is apparently a tetramer (A4). The molecular weights of subunits A/B for spinach, peas and barley were determined as 38,000/40,000, 38,000/42,000 and 36,000/39,000 respectively. 2. The NAD-specific glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12) was purified from Spinacia oleracea and Pisum sativum by affinity chromatography on blue Sepharose CL-6B. The enzyme from both plant species is shown to be a tetramer of subunits with Mr 39,000. 3. The present findings contrast with heterogeneous results obtained previously by other authors. These results suggested that there are considerable interspecific differences in the quaternary structure of glyceraldehyde-3-phosphate dehydrogenases from higher plants.
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PMID:Quaternary structure of higher plant glyceraldehyde-3-phosphate dehydrogenases. 3 50

There is no evidence, at pH 9.4, of negative cooperativity in the binding of NAD+ or NADH to rabbit muscle glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phorphorylating), EC 1.2.1.12) nor in the binding of acetyl pyridine adenine dinucleotide at pH 7.6 and ph 9.4. The binding of NAD+ to carboxymethylated enzyme at pH 7.6 and pH 9.4 also occurs without cooperativity. The possible implications of these findings for the involvement of ionising groups in the enzyme in the subunit interactions responsible for negative cooperativity, previously reported for coenzyme binding at pH 7.4--8.6, are discussed.
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PMID:Factors affecting coenzyme binding and subunit interactions in glyceraldehyde-3-phosphate dehydrogenase. 3 52


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