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)

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

Glucose when present as a sole organic carbon source in a mineral salts medium is dissimilated by Caulobacter crescentus ATCC 15252 (strain CB-2) by the Entner-Doudoroff pathway throughout the culture cycle (exponential, transition, and stationary phase). Most of the available glucose that is present at the onset of exponential growth is assimilated by the cells during the transition phase or the period associated with stalk cell development. Swarmer cell development is minimized during this phase. During this same period the pH drops from 6.1 to 4.9 as a result of an abundant excretion of acetic acid. Simultaneously, poly-beta-hydroxybutyrate accumulates within the cells at an accelerated rate. An NADP-dependent glyceraldehyde-3-phosphate dehydrogenase is also present throughout the culture cycle which subsumes the presence of the subsequent enzymes of the Embden-Meyerhof-Parnas pathway in pyruvate formation. An operative tricarboxylic acid cycle is associated with cells throughout the culture cycle.
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PMID:Pathway of glucose catabolism in Caulobacter crescentus. 1 52

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

Two novel procedures have been used to regulate, in vivo, the formation of phosphoenolpyruvate (PEP) from glycolysis in Streptococcus lactis ML3. In the first procedure, glucose metabolism was specifically inhibited by p-chloromercuribenzoate. Autoradiographic and enzymatic analyses showed that the cells contained glucose 6-phosphate, fructose 6-phosphate, fructose-1,6-diphosphate, and triose phosphates. Dithiothreitol reversed the p-chloromercuribenzoate inhibition, and these intermediates were rapidly and quantitatively transformed into 3- and 2-phosphoglycerates plus PEP. The three intermediates were not further metabolized and constituted the intracellular PEP potential. The second procedure simply involved starvation of the organisms. The starved cells were devoid of glucose 6-phosphate, fructose 6-phosphate, fructose- 1,6-diphosphate, and triose phosphates but contained high levels of 3- and 2-phosphoglycerates and PEP (ca. 40 mM in total). The capacity to regulate PEP formation in vivo permitted the characterization of glucose and lactose phosphotransferase systems in physiologically intact cells. Evidence has been obtained for "feed forward" activation of pyruvate kinase in vivo by phosphorylated intermediates formed before the glyceraldehyde-3-phosphate dehydrogenase reaction in the glycolytic sequence. The data suggest that pyruvate kinase (an allosteric enzyme) plays a key role in the regulation of glycolysis and phosphotransferase system functions in S. lactis ML3.
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PMID:In vivo regulation of glycolysis and characterization of sugar: phosphotransferase systems in Streptococcus lactis. 10 23

A host response to infection by Coxiella burneti was investigated. Infectedyolk sacs were harvested from embryonated eggs and assayed for glycolytic activity. Assays of glycolytic enzymes included glucose isomerase, aldolase, phosphofructokinase,fructose-1,6-diphoshatase, glyceraldehyde-3-phosphate dehydrogenase, enolase, and pyruvate kinase. No significant differences in enzymatic activity between normal and infected tissues through the 12th day was observed. From the 13th day through the 16thday, the glycolytic activity of normal tissues decreased. Glycolytic activity of infected tissues did not decrease, but showed a gradual increase during this same time period. Embryos from infected eggs demonstrated a gradual decrease in total weight fromthe 12th day until death occurred on the 16th day.
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PMID:Host response to infection by Coxiella burneti. 16 99

Iodoacetate inhibits glyceraldehyde-3-phosphate dehydrogenase activity in pancreatic islets and causes a time- and dose-related inhibition of glucose oxidation and lactate output by the islets. High concentrations of the drug (0.3 mM or more) fail to affect Ba2+-induced insulin secretion but inhibit glucose-stimulated proinsulin biosynthesis, 45Ca net uptake and insulin release. A mixture of fumarate, glutamate, and pyruvate, the oxidation of which is only partially reduced by iodoacetate, fails to protect the B-cell against the inhibitory effect of the drug. These findings are compatible with the view that glycolysis plays an essential role in the process of glucose-induced insulin release. At low concentrations of iodoacetate (up to 0.2 mM), the reduction in glucose metabolism coincides with a partial inhibition of proinsulin biosynthesis. However, the expected reduction in 45Ca net uptake and subsequent insulin release is masked by a concomitant facilitating action of iodoacetate, possibly due to interference with native ionophoretic processes. It is concluded that iodoacetate is not an adequate tool to dissociate, if they are dissociable, the fuel and secretory functions of glucose.
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PMID:The stimulus-secretion coupling of glucose-induced insulin release XXVI. Are the secretory and fuel functions of glucose dissociable by iodoacetate? 35 90

Glycerolization of freshly collected human erythrocytes leads to a reduction in ATP levels which return to their original values following deglycerolization. The reduction in ATP levels is largely prevented by pyruvate but not by inosine and glucose, singly or in combination. This implies that the ATP lesion associated with glycerolization reflects mainly a decrease in the NAD/NADH ratio and accordingly a reduced glyceraldehyde-3-phosphate dehydrogenase activity. 2,3-DPG levels were not influenced by glycerolization and deglycerolization. Erythrocytes depleted of ATP in the presence of glycerol can have their ATP levels repleted by either pyruvate or inosine, but require the presence of both compounds for maintenance during a post-rejuvenation incubation period. This indicates that the prolonged presence of glycerol influences both the NAD/NADH ratio and the carbon-containing intermediates of glycolysis. Glycerol did not influence ATP repletion of erythrocytes stored at 4 degrees C for 20 days by inosine in combination with pyruvate, but substantially decreased the repletion of their 2,3-DPG levels.
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PMID:Influence of glygerol on ATP and 2,3-DPG levels of human erythrocytes. 46 14

A reduction in myocardial oxygen supply during ischemia, not only leads to reduced aerobic ATP production but does not stimulate glycolytic ATP synthesis. The residual aerobically synthesized ATP comes primarily from continued inefficient (i.e., compared to glucose in terms of moles of ATP produced per mole of O2 consumed) oxidation of fatty acids. This leads to elevated tissue levels of long chain fatty acyl-CoA and fatty acyl-carnitine. Both are potentially cell damaging metabolic intermediates. Restriction of glycolysis is due to inhibition of glyceraldehyde-3-phosphate dehydrogenase by accumulated metabolites, such as H+, lactate and NADH. The reduced production of ATP leads to decreased levels of high energy phosphate stores which in turn may impair myocardial mechanical function.
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PMID:Energy metabolism in the ischemic heart. 55 21

1. The changes with the time of the activities of some energy-supplying enzymes and of the hydrolytic enzyme, acid phosphatase, were studied over 2 weeks of complete ischaemia, produced in the rat soleus muscle by section of the abdominal aorta and terminal devascularization, leaving nerve and tendon intact. 2. Activities of glycolytic enzymes, oxidative enzymes, hexokinase and acid phosphatase are affected in a different manner. Activities of the glycolytic enzymes, lactate dehydrogenase, triosephosphate dehydrogenase and glycerolphosphate dehydrogenase, are lowest on the 1st day and increase thereafter. The first two reach the control values again on the 4th and 14th day, respectively, while glycerolphosphate dehydrogenase reaches about 50% of the control value on the 14th day. The maximum decrease in activity of the oxidative enzymes, citrate synthase, beta-hydroxyacyl-CoA-dehydrogenase and malate dehydrogenase occurs later (4th day); thereafter their activity returns slowly to control values, but does not reach them even on the 14th day. Hexokinase activity is slightly decreased on the 1st day; then it increased and reached on the 7th day twice the control value. Thus on the 1st day the activity of the enzymes of aerobic metabolism prevail, and on the 4th day those of anaerobic carbohydrate (glucose) metabolism; the recovery of enzyme activity of aerobic oxidation occurs later. 3. Acid phosphatase activity increased from the 2nd day onwards, reaching up to 3 times the control value on the 4th day and still twice that value on the 14th day. This agrees well with the histochemical picture of acid phosphatase. 4. Histochemical changes of alkaline phosphatase activity reveal destruction of capillary endothelial cells during the first few days after operation and their later proliferation from the periphery, correlating with the loss and recovery of oxidative enzyme activity.
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PMID:Effects of ischaemia on enzyme-activities in the soleus muscle of the rat. 57 Nov 16

8 and 24 hours after alloxan administration, diabetic rat brain shows decreased glycogen content, significantly increased FDP, triose phosphates, pyruvate and lactate levels, a large rise in glucose and a 27% activation of anaerobic lactate production from glycogen. 48 hours after alloxan administration there is a recovery of glycogen and a fall in lactate levels. ATP and AMP levels are unchanged 8 and 24 hours after alloxan administration but the former is increased and the latter decreased 48 hours posttreatment. Insulin given to rats 8 hours after alloxan treatment reverses glycogen, FDP, triose phosphates, pyruvate and lactate levels seen in the diabetic rat brain. In addition the increament in glucose is reduced by half and the rate of anaerobic lactate formation from glycogen is restored to control values. G-6-P levels, unaffected by alloxan or insulin alone, are significantly lowered in animals which received insulin after alloxan. Phosphorylase, HK, PFK, ALD, GAPDH, PK, LDH and Glycogen synthetase activities are not modified in rat brain by administration of alloxan or insulin or both.
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PMID:Effect of alloxan and insulin on carbohydrate metabolism in rat brain. 73 60


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