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

Rabbit muscle aldolase catalyzes the exchange with solvent of all three methyl hydrogens of hydroxyacetone phosphate. Under saturating conditions, rates of the following processes have been measured: deuteration of hydroxyacetone phosphate in 2H2O (by an NMR method), tritiation of hydroxyacetone phosphate in H2O and 2H2O, and detritiation of tritiated hydroxyacetone phosphate in H2O and 2H2O. It is clear from these measurements (1) that there is no primary kinetic isotope effect and hence that hydrogen abstraction is not rate determining to the exchange and (2) that only one (as the closest integer) methyl hydrogen exchanges per turnover. The argument is made that these observations are mutually exclusive in terms of the accepted aldolase mechanism in the absence of further restrictions imposed by the enzyme. Possible restrictions are discussed.
 ...
PMID:Rabbit muscle aldolase catalyzed proton exchange of hydroxyacetone phosphate with solvent. 91 52

The influence of cysteamine on the metabolic activity of red blood cells has been estimated in vitro. Cysteamine has a marked influence on the activity of mainly aldolase F-1, 6-P and glucose-6-P dehydrogenase in red blood cells in vitro. The anaerobic metabolism of erythrocytes is more active in the presence of lower doses of cysteamine. Higher concentrations of radioprotector stimulate the pentose phosphate shunt.
 ...
PMID:The influence of the known radioprotective compounds on the metabolism of human red blood cell. Part II. The influence of cysteamine on enzymic systems. 93 45

A comparison of the product-inhibition patterns during cleavage of D-fructose 1,6-diphosphate by aldolases from yeast, rabbit muscle and Bacillus stearothermophilus shows an ordered reaction sequence for all three enzymes, with dihydroxyacetone phosphate the last-leaving product. Addition of Zn2+, Co2+, Fe2+, Mn2+ or Cd2+ ions to the inactive apo-(Bacillus stearothermophilus aldolase) restores activity to different extents, whereas Ni2+, Mg2+ or Cu2+ ions have no effect. The cleavage activity of this aldolase is not enhanced by added K+ ion. The effects of metal replacement on thermal stability, Km and Vmax. are given and the possible role of the metal is discussed in the light of these results.
 ...
PMID:Metal-replacement studies in Bacillus stearothermophilus aldolase and a comparison of the mechanisms of class I and class II aldolases. 94 70

Fifteen red cell enzyme activities of growth-retarded patients with and without growth hormone (GH) deficiency were investigated before and after GH administration. The 15 enzymes were Hexokinase, phosphoglucomutase, glucose phosphate, isomerase, phosphofructokinase, fructose diphosphate aldolase, glyceraldehyde-3-phosphae dehydrogenase, triosephosphate isomerase, 2,3-diphosphoglycerate mutase, 3-phosphoglycerate kinase, 3-phosphoglycerate mutase, enolase, pyruvate kinase, glycose-6-phosphate dehydrogenase, 6-phosphogluconic dehydrogenase, glutathione reducase. Sixty-six subjects were studied: 30 normal control subjects (group N) and 36 patients (aged 5-23 years) with short stature. Complete endocrine evaluation showed 21 (group I) to have GH deficiency (10 patients with isolated GH deficiency) and 15 (group II) to have normal hypothalamic and pituitary function except for two patients with a moderate hypothyroidism. Both had been receiving thyroid hormone treatment for a long time before our studies. All 36 patients were treated with 2 mg human growth hormone intramuscularly for 7 days. Before GH treatment no significant difference was observed between hematologic data in group I (GH deficiency) and group II (no GH deficiency). After GH therapy there was a significant increase in reticulocyte count in both groups of patients with short stature. The mean pretreatment value in group I was 1.294% +/- 0.084 (SEM); the mean post-treatment value was 2.081% +/- 0.287 (SEM)< P less than 0.005. The mean pretreatment value in group II was 1.0% 0.184 (SEM); the mean post-treatment value was 1.407% +/- 0.193 (SEM), P less than 0.01. In group II (no GH deficiency) mean pretreatment erythrocyte enzyme activities were not significantly different from those activities observed in normal control subjects (group N). However, in patients who lacked GH, the pretreatment activities of five red cell enzymes (glucose phosphate isomerase, triosephosphate isomerase, glyceraldehyde-3-phosphate dehydrogenase, 2,3-diphosphoglycerate mutase, 3-phosphoglycerate kinase) were significantly decreased before GH administration compared with the values in normal control subjects...
 ...
PMID:Action of growth hormone on erythropoiesis: changes in red blood cell enzyme activities in growth-retarded patients with and without growth hormone deficiency. 95 53

An X-ray crystallographic structure determination has been carried out on 2-keto-3-deoxy-6-phosphogluconic (KDPG) aldolase at 3.5-A resolution using the multiple isomorphous replacement method with three heavy atom derivatives along with anomalous dispersion contributions from two of the derivatives. Crystals grown from ammonium sulfate-phosphate buffered (pH 3.5) solutions were: cubic, a= 103.40 (4) A, space group P213. KDPG aldolase consists of trimeric heterologous assemblages utilizing crystallographic threefold symmetry. The overall profile of the oligomeric structure viewed down the threefold axis resembles that of a ship propeller while the subunits are approximate irregular oblate ellipsoids (25 X 45 X 45 A). The folding of most of the polypeptide chain was traced unambiguously. Secondary structural features consist of nine helical regions (75 residues, 35%) and a pair of two parallel chains. The subunit contains a long empty channel which is about 9 X 9 X 30 A with one of the pair of parallel chains forming part of the wall. Three mercury binding sites are located in this channel. These might correspond to the two readily accessible and one of the two buried cysteine residues of each subunit. The channel terminates with another cavity of about 8 X 10 X 25 A near the surface of the oligomeric structure. The regions of the subunits near the threefold axis are characterized by a high degree of secondary structural organization and these make close intersubunit contacts. Quarternary interactions are due mainly to side-chain interactions of helices.
 ...
PMID:The folding and quaternary structure of trimeric 2-keto-3-deoxy-6-phosphogluconic aldolase at 3.5-A resolution. 97 67

Activities of both aldolases were distinctly decreased in acute kidney insufficiency, caused by administration of uranyl acetate. The decrease in the activity of fructose-1,6-diphosptate aldolase was more distinct which led to alteration in ratio between fructose -1,6-diphosphate and ketose-1-phosphate aldolases. The isozyme spectra of the enzymes were also altered. Isozymes of fructose-1,6-diphosphate aldolase AB2 and of ketose-1-phosphate aldolase form 22 possessed the same electrophoretic mobility but their relative activity was increased 2-3-fold under conditions of the acute kidney insufficiency. At the same time, the more electrophoretically mobile isozymes were not detected.
 ...
PMID:[Fructose-1,6-diphosphate aldolase and ketose-1-phosphate aldolase isoenzyme spectra in the kidneys normally and in uranyl acetate poisoning]. 102 33

Rabbit muscle aldolase is irreversibly modified by the arginine-selective alpha-dicarbonyl, phenylglyoxal, loss of activity correlating with the unique modifications of one arginine residue per subunit, as determined by amino acid analysis, and (7-14C)phenylglyoxal incorporation. The affinity of the modified enzyme for dihydroxyacetone phosphate is significantly reduced while substantial protection against inactivation is afforded by fructose 1,6-disphosphate, dihydroxyacetone phosphate or phosphate ion. The nature of the substrate C-1 phosphate binding site in this enzyme is discussed in the light of these and other results.
 ...
PMID:A functional arginine residue in rabbit-muscle aldolase. 103 58

Escherichia coli GH352, which was originally described as a temperature-sensitive strain containing a thermolabile acyl coenzyme A:monoacylglycerol 3-phosphate acyltransferase, does not now contain a thermolabile form of this enzyme. It has a defect in fructose-1,6-diphosphate aldolase and at least one additional temperature-sensitive lesion. Both strains GH352 and NP315, a temperature-sensitive aldolase mutant, show rapid cessation of 32-P1 incorporation into nucleic acids and phospholipids at 42 C. These characteristics of strain GH352 are therefore no longer attributed to thermolabile phospholipid synthesis, but can be attributed to the fructose-1,6-diphophate aldolase lesion.
 ...
PMID:Rapid cessation of phospholipid synthesis in fructose-1,6-diphosphate aldolase mutants of Escherichia coli. 109 57

Chemostat cultures of Erwinia amylovora 595, grown in mineral salts-nicotinic acid medium at 30 degrees C, and limited by D-glucose concentrations in the presence of dissolved oxygen tensions (D.O.T.) greater than about 6mm Hg, became limited by oxygen availability below about 4 mm Hg. This latter limitation was accompanied by a marked increase in acid production as the D.O.T. was depressed. The transition between D-glucose- and oxygen-limitation was also characterized by a maximum in succinate oxidase activity, and a minimum in the in situ respiration. D-Glyceraldehyde-3-phosphate dehydrogenase and D-fructose-1, 6-diphosphate aldolase showed small reductions in specific activity in the region 4-6 mm Hg D.O.T., but further reduction to 2 mm Hg resulted in a marked increase in the specific activity of aldolase. Malate dehydrogenase followed the converse trend, and attained very low activity levels when the D.O.T. decreased beyond the lower limits of detection. The in situ respiration was maximal at 2 mm Hg D.O.T., while potential respiration values were minimal at 2 mm Hg, and maximal at about 8 mm Hg D.O.T. The insitu respiration rate was proportional to dilution rate (D), in presence of excess oxygen, up to 0.18 h-1, after which a marked diminution occurred and continued until the wash-out rate was attained. Succinate oxidase activity decreased with increase in dilution rate, but remained constant above D equals 0.18 h-1. Malate dehydrogenase showed a persistent decline with increase in dilution rate, while D-glyceraldehyde-3-phosphate activity increased somehwat at higher dilution rates. The data are interpreted in terms of two transition points, at 6 and 2 mm Hg D.O.T., and of a change from respiratory to fermentative metabolism at low D.O.T., and at high dilution rates.
 ...
PMID:Variation in the activity levels of selected enzymes of Erwinia amylovora 595 in response to changes in dissolved oxygen tension and growth rate of D-glucose-limited chemostat cultures. 111 45

Polyacrylamide-disc gel electrophoresis and quantitative enzyme assays showed that the pathways of glucose catabolism and secondary metabolism in Penicillium expansum were dependent on the degree of aeration of the cultures. The isoenzyme patterns and specific activities of aldolase and succinate dehydrogenase indicated that glycolysis and the tricarboxylic acid cycle operated under conditions of both limited and efficient aeration (i.e. in cultures grown statically or on an orbital shaker). At high levels of aeration the growth rate was faster and synthesis of extracellular pectolytic enzymes was enhanced, whilst the activities of glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase showed that the pentose-phosphate shunt was important in glucose catabolism during the trophophase of growth. In contrast, under conditions of low aeration this latter pathway was virtually undetectable, growth was slower, pectolytic enzyme production low and large concentrations of secondary metabolites (6-methylsalicylic acid, patulin and citrinin) accumulated.
 ...
PMID:The effects of aeration on glucose catabolism in Penicillium expansum. 117 56


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>