Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.2.13 (aldolase)
 3,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Histochemical studies have been conducted by applying hexokinase (HK), aldolase (AD), glyceraldehyde-3-phosphate dehydrogenase (G3), succinate dehydrogenase (SDH), glucose-6-phosphate dehydrogenase (G6PD), and thiamine pyrophosphatase (TPPase) methods, as well as Nissl staining and Gomori's chrome-alum-hematoxylin-phloxine (CHP) methods to intercalated neurons of the supraoptic nucleus (SO) on Wistar strain rats. Intercalated neurons reacted weakly to the AD, G3, G6PD, and SDH tests, indicating that they belong to the category of ordinary neurons with low carbohydrate metabolism. Many fibrous astrocytes showing strong HK reactions surround neurosecretory neurons. However, they do not surround intercalated neurons with mild HK activity. These results indicate that the latter receive a poor supply of energy from glucose in the circulating blood in contrast to the former. Intercalated neurons are very rich in Nissl substance but lack CHP-positive material. They may have a high potential for synthesizing protein. The principal morphological features of the TPPase-positive Golgi material are peculiar and heterogeneous shape and poor development. These findings together with mild G6PD activity suggest that intercalated neurons are very likely to have poor synthesizing activity.
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PMID:Histochemical studies on the distribution of thiamine pyrophosphatase and enzymes related to carbohydrate metabolism in the intercalated neurons of the rat supraoptic nucleus. 613 41

We report the establishment of a phylogenetic relationship between the sterol-nonrequiring mycoplasmas (Acholeplasma species) and streptococci. Three specific antisera prepared against purified Streptococcus faecalis fructose diphosphate aldolase and glyceraldehyde-3-phosphate dehydrogenase and Pediococcus cerevisiae glyceraldehyde-3-phosphate dehydrogenase were used for comparative enzyme immunological studies; the Ouchterlony double-diffusion technique and the quantitative microcomplement fixation procedure were employed. The reactions obtained provide evidence showing that all seven ACholeplasma species studied (A. laidlawii, A. granularum, A. modicum, A. oculi, A. axanthum. A. hippikon, and A. equifetale) are phylogenetically related to streptococci and that they evolved from streptococci. The data strongly suggest that the acholeplasmas comprise a distinct evolutionary group that has diverged from streptococci belonging to Lancefield group D or N. No reactions were observed between these enzyme antisera and cell extracts from six fermentative Mycoplasma species. These results support the view that mycoplasmas are derived from various bacteria.
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PMID:Origins of the mycoplasmas: sterol-nonrequiring mycoplasmas evolved from streptococci. 617 74

Red cell enzymes, 2,3-diphosphoglycerate (2,3-DPG) and adenosine triphosphate (ATP), were evaluated in a 23-mo-old boy with juvenile chronic myelocytic leukemia (JCML) at the onset of his illness and 6 mo later during the accelerated phase. The activities of the age-dependent red cell enzymes, hexokinase, aldolase, pyruvate kinase, and glucose-6-phosphate dehydrogenase, were elevated, as were the concentrations of red cell 2,3-DPG and ATP, consistent with a young red cell population metabolizing at an increased glycolytic rate. The activities of the non-age-dependent enzymes, glyceraldehyde-3-phosphate dehydrogenase (G3PD), phosphoglycerate kinase, and enolase, were also increased to levels similar to or greater than those observed in term infants. As the illness progressed, the activity of red cell G3PD increased further, and phosphoglucose isomerase activity increased markedly. These results are consistent with the prior suggestion that JCML represents a reversion to "fetal" erythropoiesis.
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PMID:Fetal erythropoiesis in juvenile chronic myelocytic leukemia. 622 20

In order to evaluate properly red cell metabolic data obtained in newborns with congenital hemolytic disorders, the unique metabolic characteristics and normal developmental changes that occur prenatally and postnatally are presented. The age-dependent red cell glycolytic enzymes (hexokinase, aldolase, pyruvate kinase) and glucose-6-phosphate dehydrogenase and most glycolytic intermediates are elevated at birth and at 11 to 12 months of age, consistent with the presence of a young red cell population the entire first year of life. However, certain red cell enzymes are elevated out of proportion to the age of the red cell population [phosphoglucose isomerase. glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase (PGK), and enolase (ENO)] whereas others are decreased [phosphofructokinase (PFK), glutathione peroxidase, carbonic anhydrase, and others]. These metabolic characteristics are felt to be unique and representative of "fetal erythropoiesis." Activities of PGK and ENO decrease the PFK increases toward normal adult values beginning at eight to nine weeks of age. The concentration of glucose-6-phosphate steadily increases after birth and peaks at three to four weeks of age, at a time when PFK activity remains relatively unchanged, suggesting a relative block in glycolysis at the PFK step secondary to an enzyme with both decreased activity and altered kinetic properties (a "fetal" isozyme). Thus, evaluation of red cell enzyme and glycolytic intermediate data obtained in the first year of life should be related to the knowledge that a young red cell population is present and the characteristic unique metabolic red cell alterations described in cord blood persist beyond the immediate neonatal period.
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PMID:Red cell enzymopathies in the newborn. I. Evaluation of red cell metabolism. 628 May 78

A histochemical multi-step technique for the demonstration of phosphofructokinase activity in tissue sections is described. With this technique a semipermeable membrane is interposed between the incubating solution and the tissue sections preventing diffusion of the non-structurally bound enzyme into the medium during incubation. In the histochemical system the enzyme converts the substrate D-fructose-6-phosphate to D-fructose-1,6-diphosphate, which in turn is hydrolyzed by exogenous and endogenous fructose diphosphate aldolase to dihydroxyacetone phosphate and D-glyceral-dehyde-3-phosphate. The dihydroxyacetone phosphate is reversibly converted into D-glyceraldehyde-3-phosphate by exogenous and endogenous triosephosphate isomerase. Next the D-glyceraldehyde-3-phosphate is oxidized by exogenous and endogenous glyceraldehyde-3-phosphate dehydrogenase into 1,3-diphospho-D-glycerate. Concomitantly the electrons are transported via NAD+, phenazine methosulphate and menadione to nitro-BT. Sodium azide and amytal are incorporated to block electron transfer to the cytochromes.
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PMID:Histochemical technique for the demonstration of phosphofructokinase activity in heart and skeletal muscles. 644 32

The extent of binding of glycolytic enzymes to the particulate fraction of homogenates was measured in sheep hind muscles after electrical stimulation. As compared to the control muscles, stimulation led to significant increases in the amount of phosphofructokinase, aldolase and glyceraldehyde-3-phosphate dehydrogenase bound to the particulate fraction. The binding of other glycolytic enzymes was not significantly altered. A servey of different hind limb muscles at variable rates of stimulation revealed that each muscle exhibited its own characteristic response pattern in terms of the level of increased enzyme binding. Generally, an increased stimulation rate led to greater enzyme adsorption. The increase in enzyme binding was rapidly reversible for it was shown that the amount of enzyme bound quickly returned to control values when the muscles were allowed to recover in the live anaesthetised animal following cessation of stimulation. Those muscles which exhibited increased enzyme binding were characterised by a marked loss of glycogen and accumulation of lactate suggesting that accelerated glycolytic flux was a necessary condition for the observation of increased enzyme binding. In support of this, enzyme adsorption was observed to the greatest on stimulation of ischemic muscles, whereas in trained muscles, or muscles with depleted glycogen stores induced by prior adrenalin treatment, the increased enzyme binding response was greatly diminished. It is concluded that the variable binding of key glycolytic enzymes has a role to play in the regulation of glycolytic behaviour in skeletal muscle.
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PMID:The reversible binding of glycolytic enzymes in ovine skeletal muscle in response to tetanic stimulation. 645 61

Assay of maximal activities of 11 glycolytic enzymes in cell-free buffalo sperm extracts showed that hexokinase, phosphofructokinase and glyceraldehyde-3-phosphate dehydrogenase had the lowest activities, suggesting regulation of fructolysis at steps catalysed by these enzymes. The ratios of glyceraldehyde-3-phosphate dehydrogenase/phosphofructokinase (0.67) and phosphoglycerate kinase/phosphofructokinase (4.60) are typical of cells exhibiting high Pasteur effect (50% for ejaculated buffalo spermatozoa). The regulatory nature of phosphofructokinase was shown through its modulation by ATP, AMP and inorganic phosphate. The determination of fructolytic intermediates and cofactors and calculation of mass action ratios for each enzymic step revealed that hexokinase, phosphofructokinase, fructose-biphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase and pyruvate kinase catalysed reactions far removed from the equilibrium. A regulatory role by glyceraldehyde-3-phosphate dehydrogenase appeared to be most likely because triosephosphates and inorganic phosphate accumulated more under anaerobic than under aerobic conditions.
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PMID:REgulation of glycolysis/fructolysis in buffalo spermatozoa. 645 53

A simple screening procedure for the detection of glucose-phosphate isomerase (GPI), phosphofructokinase (PFK), aldolase (AL) and glyceraldehyde-3-phosphate dehydrogenase (GAPD) deficiencies in blood, is described. These enzymes catalyze the second, third, fourth, and sixth reactions in the Embden-Meyerhof pathway. The procedure is based on the conversion of glucose-6-phosphate to 1,3-diphosphoglycerate (1,3-DPG) which is catalyzed by the sequential action of the GPI, PFK, AL and GAPD. The presence of the enzyme activities is visually estimated by the reduction of NAD+ (non-fluorescent) to NADH (fluorescent) which occurs when 1,3-DPG is formed. Absence of fluorescence indicates the deficiency of anyone of the four enzymes, which are specified by using separately the PFK, AL and GAPD respective substrates.
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PMID:A simple screening procedure for glucose phosphate isomerase, phosphofructokinase, aldolase and glyceraldehyde-3-phosphate dehydrogenase deficiencies. 646 Apr 65

Results of studies on the interactions of aldolase and glyceraldehyde-3-phosphate dehydrogenase with erythrocyte ghosts have been reinterpreted by making allowance for possible multivalency of the enzymes in regard to their interactions with matrix sites. It is shown that the curvilinearity of the experimental Scatchard plots may be attributed fully to the formation of enzyme-membrane complexes in which tetravalent enzyme may form crosslinks between several membrane sites. This interpretation of the results is preferable to earlier analyses based on heterogeneity of membrane sites in that (a) it takes into account the tetrameric nature of aldolase and glyceraldehyde-3-phosphate dehydrogenase, and (b) it is consistent with experimental demonstrations that band 3 protein is the sole site for enzyme interaction with the erythrocyte matrix. The dependence on ionic strength of the intrinsic association constant for either interaction is such that the binding of neither aldolase nor glyceraldehyde-3-phosphate dehydrogenase could be detected at ionic strengths in excess of 0.08 I. This finding is discussed in relation to the claims and counterclaims concerning the physiological significance of these interactions between glycolytic enzymes and erythrocyte membranes.
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PMID:Quantitative characterization of the interactions of aldolase and glyceraldehyde-3-phosphate dehydrogenase with erythrocyte membranes. 649 88

Perfused rat hearts show a markedly increased binding of phosphofructokinase and fructose-bisphosphate aldolase as a consequence of ischaemia, but little change in binding of pyruvate kinase, lactate dehydrogenase or glyceraldehyde-3-phosphate dehydrogenase. After 10 min ischaemia over one quarter of the phosphofructokinase and three quarters of the aldolase are bound. The effect of anoxia is less well marked in its influence on binding with only aldolase showing a significant increase in binding. These results suggest that one factor involved in the increased binding during ischaemia is the fall in pH of the heart. Binding studies with isolated myofibrils confirm that the affinity and stoichiometry of aldolase binding are considerably increased as the pH is lowered over a range comparable to that which occurs in ischaemic heart. The low level of binding of glyceraldehyde-3-phosphate dehydrogenase in perfused rat hearts correlates with the relatively low affinity of this enzyme for binding to rat or rabbit cardiac myofibrils. There are species differences in the enzyme binding response to ischaemia. Sheep hearts show rapid and large increases in the binding of glyceraldehyde-3-phosphate dehydrogenase in addition to changes in aldolase and phosphofructokinase binding. The greater binding of glyceraldehyde-3-phosphate dehydrogenase reflects the greater affinity of sheep cardiac myofibrils. It is suggested that the altered metabolic demands of ischaemia are satisfied by changes in glycolytic enzyme organisation as the enzymes shift from the soluble to the particulate phase of cardiac muscle.
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PMID:Metabolic dependence of glycolytic enzyme binding in rat and sheep heart. 669 39


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