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)

In this study pyruvate kinase, hexokinase and aldolase are investigated in two types of embryonal tumors, neuroblastomas and medulloblastomas; the results are compared with similar studies in gliomas. The activities of hexokinase and pyruvate kinase are significantly decreased in neuroblastomas. In neuroblastoma and medulloblastoma all five forms of pyruvate kinase (K4, K3M, K2M2, KM3 and M4) are present. In contrast, the gliomas investigated are characterized by the presence of mainly K4 and a little K3M. In neuroblastomas, medulloblastomas and gliomas, hexokinase type I is present; in addition, hexokinase type II is present in two medulloblastomas. Aldolase A is the predominant isozyme in all tumors investigated; this is in contrast with normal nervous tissue. It can be concluded that the isozyme characteristics especially of pyruvate kinase from neuroblastomas and medulloblastomas are comparable with similar findings in retinoblastoma; these findings support the hypothesis that these three tumors have a common embryonic origin.
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PMID:Glycolytic enzymes from human neuroectodermal tumors of childhood. 632 86

Aldolase activity with the two substrates fructose-1-phosphate and fructose-1,6-diphosphate was measured in the homogenate of small intestinal biopsy specimens from children with different malabsorptive diseases (celiac disease, cow's milk protein intolerance, infectious diarrhea, giardiasis, and Crohn's disease) and controls. It is demonstrated that the ratio of fructose-1,6-diphosphate/fructose-1-phosphate activity, which reflects the relative amounts of the crypt enzyme aldolase A (EC 4.1.2.13) and the villous enzyme aldolase B (EC 4.1.2.7), correlates very well with both the ratio of crypt to villous height (correlation factor r = 0.92) and the mitotic index (r = 0.80).
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PMID:Biochemical quantification of crypt hyperplastic villous atrophy by aldolase activity assay. 648 61

13 patients were undergone a resection of their lung tumours. Under operation aldolase were determined in V. pulmonalis, A. pulmonalis and V. basilica. First time it is demonstrated: Human bronchial carcinomas give aldolase in circulating blood. Aldolase-level in V. pulmonalis of carcinoma increases with size and dedifferentiation of tumours.
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PMID:[Increase in serum aldolase caused by bronchial carcinoma]. 649 83

Several aldolase B clones from a human liver cDNA library have been identified by using a rabbit aldolase A cDNA as a hybridization probe. The most complete of these, pHL413, is 1389 base pairs long and covers approximately equal to 80% of the length of the mRNA, including 90% of the translated region. The cDNA, pHL413, was used to identify a genomic clone, lambda HG313, which encoded the remaining amino acids of human aldolase B. We demonstrate that the amino acid and nucleotide sequences of aldolase are strongly conserved even between different isozymes. Furthermore, in the 3'-untranslated regions of the mRNAs for the B isozyme of human and rat there is an extensive stretch of homology. Aldolase B lacks a cysteine at positions 72 and 338 and lacks a histidine at position 361. These residues, which are present in rabbit aldolase A, have previously been proposed to take part in catalysis. Our findings suggest that this may not be the case.
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PMID:Complete amino acid sequence for human aldolase B derived from cDNA and genomic clones. 658 24

Cathepsin L was capable of destroying rabbit muscle aldolase (D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase, EC 4.1.2.13) activity towards the substrate fructose 1,6-bisphosphate. The rate of loss of activity towards this substrate was stimulated (approx. 2-fold) by physiological concentrations of ATP and to a lesser degree by GTP, CTP, UTP, ADP and cyclic AMP, while PPi and Pi decreased the rate of inactivation. Other proteinases (cathepsin B, cathepsin D, trypsin and chymotrypsin) also decreased aldolase activity toward fructose 1,6-bisphosphate more rapidly in the presence of ATP and more slowly in the presence of Pi. Cathepsin L, at higher concentrations, was capable of inactivating aldolase activity towards fructose 1-phosphate and extensively degrading the enzyme; these reactions were not affected by ATP and Pi. The thermostability of aldolase was also unaffected by these ligands. ATP and Pi had no effect on the rates of hydrolysis of other proteins (hemoglobin, bovine serum albumin, casein and azocasein) by cathepsin L. These data indicate that the effects of ATP and Pi are due to interactions of these ligands with aldolase that make the enzyme more vulnerable to limited but not extensive proteolysis; these ligands do not directly affect cathepsin L activity.
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PMID:Inactivation of fructose-1,6-bisphosphate aldolase by cathepsin L. Stimulation by ATP. 669 88

A solid-phase, noncompetitive radioimmunoassay has been developed for aldolase B in human serum and tissues. Aldolase B was purified from human liver, and specific antisera to purified aldolase B were obtained from chickens. Specific antihuman aldolase B IgG was purified by affinity chromatography. Disposable polypropylene plates were coated with affinity purified specific IgG antibody and used for radioimmunoassay with 125I-specific IgG antibody to aldolase B. The nonspecific binding was minimized by saturating the binding sites of the plates with 2% ovalbumin in 0.1% Tween 20. This radioimmunoassay is specific for the aldolase B subunit, with no cross-reactivity with human aldolase A or aldolase C subunits. Aldolase B is predominantly found in normal liver. Relatively high aldolase B levels are also observed in kidney. Serum levels of aldolase B in 21 normal subjects ranged from 21 to 39 ng per ml, with a mean of 28.7 +/- 8.6 (2 S.D.) ng per ml. Forty of 42 (95%) patients with acute and chronic hepatitis without cirrhosis had serum aldolase B levels greater than 40 ng per ml. Serum aldolase B levels correlated well with total serum aldolase enzyme activities (r = 0.967) and SGPT (r = 0.951) in patients with liver diseases. In cancer patients, serum aldolase B was slightly elevated in 15 of 26 (58%) patients with cancer metastatic to the liver or primary liver cell carcinoma, whereas no elevation of serum aldolase B was observed in 16 cancer patients without liver metastasis. Measurements of aldolase B serum levels by radioimmunoassay appear to be a useful measure of liver cell necrosis from benign or malignant liver diseases.
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PMID:Human aldolase B serum levels: a marker of liver injury. 672 19

The localization of a fetal isoenzyme of aldolase (A) in rat liver cells early after a single injection of carcinogen 4-dimethylaminoazobenzene and its noncarcinogenic analog 4-diethylaminoazobenzene has been studied using the immunofluorescent method. Aldolase A was found in the cytoplasm of oval and "transition" cells. These cells appeared in rat liver as a result of treatment with carcinogen and its analog. In mature hepatocytes aldolase A was not found either in intact rat liver, after the treatment with carcinogen or its analog.
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PMID:[Localization of embryonic aldolase isoenzyme in rat liver cells after a single injection of the carcinogen, 4-dimethylaminoazobenzene, and its noncarcinogenic analog]. 677 94

Alkanediol monoglycolate bisphosphoric esters (P-O-CH2-CO-O-(CH2)n-O-P), which are analogues of the aldolase (D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase, EC 4.1.2.13) substrate fructose 1,6-bisphosphate, were synthesized and used for probing its active site. The Ki value was lowest when the maximum distance between the phosphorus atoms of the bisphosphate was brought close to that of fructose 1,6-bisphosphate. The binding constants estimated from difference spectra correlate well with Ki values for the substrate analogues. Propanediol monoglycolate bisphosphoric ester protected aldolase from inactivation by 1,2-cyclohexanedione, which preferentially attacks arginine-55. However, propanol phosphate had little protective effect. The synthesized phosphate compounds protected the enzyme against inactivation by trypsin, and also against spontaneous denaturation. These results suggest that the synthesized phosphate compounds bind to aldolase at the active site, which tends to keep the distance constant between the two phosphate-binding sites for the open-chain form of fructose 1,6-bisphosphate, and stabilize the natural conformation of the enzyme. Both arginine-55 and lysine-146 are shown to participate in the phosphate-binding site for the C-1-phosphate of fructose 1,6-bisphosphate.
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PMID:An exploration of the binding site of aldolase using alkanediol monoglycolate bisphosphoric esters. 682 94

When leupeptin, a thiol protease inhibitor of microbial origin, was injected into rats, the activity of fructose-1,6-bisphosphate aldolase (D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase, EC 4.1.2.13) in the liver decreased to about 60% of that in control rats. However, the concentration of aldolase protein in the liver extracts, measured with a specific antibody obtained with enzyme purified on a phosphocellulose column, remained unchanged. Injection of leupeptin also caused a marked increase in the activities of free lysosomal proteases, such as cathepsin B (EC 3.4.22.1), cathepsin L (EC 3.4.22.-), cathepsin D (EC 3.4.23.5) and lysosomal carboxypeptidase A in the cytosol fraction. A clear inverse relationship between aldolase and cathepsin B activities in the cytosol fraction was demonstrated. The possibility that the less active form of aldolase detected in the livers of leupeptin-treated rats was produced during homogenization was excluded by showing that the aldolase activity was not changed by addition of various protease inhibitors to the homogenization medium., When insulin was coinjected with leupeptin, increase in the activity of free cathepsin L and decrease of activity of aldolase produced by the injection of leupeptin was prevented. These findings indicate that modification of aldolase may be due to the action of a lysosomal protease(s). Enhanced sensitivity of lysosomes to osmotic shock was demonstrated in the livers of leupeptin-treated rats, suggesting that the lysosomal membrane is labilized by administration of leupeptin. Incubation of the purified aldolase with the lysosomal fraction produced the same changes in properties of aldolase as those observed in vivo on injection of leupeptin.
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PMID:Proteolytic modification of rat liver fructose-1,6-bisphosphate aldolase by administration of leupeptin in vivo. 702 Jul 65

At pH 7.0 and 25 degrees C, NBF-Cl (4-chloro-7-nitrobenzofurazan) reacts rapidly with rabbit muscle aldolase (D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase, EC 4.1.2.13) to yield a product with an absorption maximum at 402 nm, which is shifted to 422 nm upon acid denaturation. The reaction involves arylation of a single cysteine residue per subunit of tetrameric aldolase, as shown by the molar absorptivity of NBF-aldolase and by titration of sulfhydryl groups of the enzyme with 5,5'-dithiobis(2-nitrobenzoic acid), DTNB. The site of arylation appears to be Cys-237, which is the cysteine residue that reacts most rapidly with DTNB. The site of arylation appears to be Cys-237, which is the cysteine residue that reacts most rapidly with DTNB, and which is not essential for aldolase activity. Arylation of the enzyme is 13-20-times more rapid than that of model compounds. The relatively high rate of arylation is not due to medium effects, to an anomalously low pKa of Cys-237, or to the presence of a binding site for NBF-Cl, and is tentatively assigned to acid-base catalysis by other functional groups in the vicinity of the reactive sulfhydryl group. The NBF-Cl reaction provides the most efficient means of titrating Cys-237 residues in rabbit muscle aldolase.
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PMID:Selective arylation of cysteine-237 of rabbit muscle aldolase with 4-chloro-7-nitrobenzofurazan. 705 73


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