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)

1) A lysosomal protease, a new cathepsin that inactivates glucose-6-phosphate dehydrogenase [EC 1.1.1.49] and some other enzymes and differs from cathepsin B [EC 3.4.22.1] was purified about 2,200-fold from crude extracts of rat liver by cell-fractionation, freezing and thawing, acetone treatment, gel filtration, and DEAE Sephadex and CM-Sephadex column chromatographies. 2) The new cathepsin was markedly activated by the thiol-reagent, 2-mercaptoethanol and inhibited by monoiodoacetate. 3) The molecular weight of the new cathepsin was found by Sephadex G-75 column chromatography to be 22,000, which is smaller than that of cathepsin B. 4) The optimum pH of the enzyme for inactivation of glucose-6-phosphate dehydrogenase was pH 5.0--5.5. The enzyme was unstable in alkali and on heat treatment. 5) The rates of inactivation of glucose-6-phosphate dehydrogenase, apo-ornithine aminotransferase [EC 2.6.1.13], apo-tyrosine aminotransferase [EC 2.6.1.5], apo-cystathionase [EC 4.4.1.1], glucokinase [EC 2.7.1.2], glyceraldehyde-3-phosphate dehydrogenase [EC 1.2.1.12], and malate dehydrogenase [EC 1.1.1.37] by the new cathepsin were higher than those by cathepsin B. However aldolase [EC 4.1.2.13] was inactivated more rapidly by cathepsin B than by the new cathepsin. Lactate dehydrogenase [EC 1.1.1.27], glutamate dehydrogenase [EC 1.4.1.2] and alcohol dehydrogenase [EC 1.1.1.1] were not inactivated by either cathepsin. Unlike cathepsin B, the new cathepsin scarcely hydrolyzes N-substituted derivatives of arginine.
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PMID:Purification and properties of a new cathepsin from rat liver. 3 59

Cathepsin B from rat liver was purified to apparent homogeneity by cell-fractionation, freezing and thawing, acetone treatment, gel filtration, DEAE-Sephadex and CM-Sephadex column chromatography, and was crystallized. The purified enzyme formed spindle-shaped crystals and its homogeneity was proved by disc gel electrophoresis in the presence of sodium dodecyl sulfate and by ultracentrifugal analysis. Its s20,w value was 2.8 S and its relative molecular mass was calculated to be 22,500 (+/- 900) by sedimentation equilibrium analysis. Crystalline cathepsin B was shown to consist of four isozymes with isoelectric points between pH 4.9 and 5.3, the main isozyme having an isoelectric point of pH 5.0. The enzyme was irreversibly inactivated by exposure to weak alkali. The pH optimum was 6.0 with alpha-N-benzoyl-DL-arginine-4-nitroanilide as substrate. Amino acid analysis showed that the enzyme contained hexosamine, glucosamine and galactosamine. Cathepsin B inactivated aldolase, glucokinase, apo-ornithine aminotransferase, and apo-cystathionase, but the rates of inactivation of glucokinase, apo-ornithine aminotransferase, and apocystathionase were lower than that of aldolase. Studies by polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate showed that cathepsin B degraded apo-ornithine aminotransferase to two polypeptide chains differing in relative molecular mass and electrophoretic mobility.
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PMID:Crystallization and properties of cathepsin B from rat liver. 4 40

Rat muscle was extracted at pH 4 and submitted to gel-filtration on Sephadex G-75 and to chromatography on DEAE-Sephadex. Gel-filtration gave a large peak of activity towards Bz-Arg-NNap with an estimated molecular weight of 25,500. Activity towards Bz-Arg-NH2 was present in this peak and in another peak of molecular weight 45,000. The second peak also hydrolysed benzoyl-glycyl-L-arginine. DEAE-Sephadex gave five peaks of Bz-Arg-NNap hydrolysing activity; all showed thiol dependence. Peaks III, IV and V hydrolysed Z-Ala-Arg-Arg-NNap-OMe rapidly; they also inactivated aldolase and were strongly inhibited by leupeptin. They are probably isoenzymes of cathepsin B1. Peak I showed these properties to a relatively small extent. 7-(N-Benzoyl-DL-argininamide)-4-methylcoumarin appears to be an alternative substrate for cathepsin B1; it was hydrolysed also by peak I, but relatively less rapidly. Peaks I and II were inhibited more than peaks III, IV and V by a muscle extract. Total activity of the Bz-Arg-NH2-hydrolysing enzyme in extensor digitorum longus muscle increased after denervation.
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PMID:Separation of cathepsin B1 and related enzymes from rat skeletal muscle. 45 46

1. The enzyme activity in the particulate fraction from rat liver that hydrolyzes alpha-N-benzoyl-DL-arginine-2-naphthylamide (Bz-Arg-NNap) has been separated into two approximately equal components by chromatography on DEAE-cellulose. One component (peak II) is completely retained by the column at low ionic strength while the other component (peak I) passes through. 2. In contrast to the enzyme in peak I, the enzyme in peak II is extremely sensitive to inhibition by leupeptin, it will hydrolyze carbobenzoxy-alanylarginylarginyl-4-methoxy-2-naphthylamine, and it will inactivate aldolase. 3. There appears to be also a minor high molecular weight component of the alpha-N-benzoyl-DL-arginyl-2-naphthylamine-hydrolyzing activity that is retained by the DEAE-cellulose but which has properties similar to those of the peak I enzyme.
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PMID:Fractionation of the rat liver enzymes that hydrolyze benzoyl-arginine-2-naphthylamide. 115 86

Candida albicans antigens which reacted with immunoglobulin E (IgE) antibodies of 57 allergic patients were detected by immunoblotting. Of the various antigens, the 175-, 125-, 46-, 43-, and 37-kDa antigenic components reacted most frequently with the patient sera. To purify the major antigens, C. albicans cells were fractionated. The 46-, 43-, and 37-kDa antigens were recovered in cytoplasmic fractions, but the 175- and 125-kDa antigens were not recovered in any fraction. The 46-, 43-, and 37-kDa antigens were purified from cytoplasmic fractions by DEAE and P11 ion-exchange chromatography. Antigens were isolated by cutting bands out of sodium dodecyl sulfate-polyacrylamide gels. The purified components confirmed by immunoblotting were next processed for amino acid sequencing. Parts of the sequences of the 46-, 43-, and 37-kDa antigens had significant levels of homology with Saccharomyces cerevisiae glycolytic enzyme enolase, phosphoglycerate kinase, and aldolase, respectively. Rabbit IgG antibodies prepared against the 46- and 43-kDa antigens strongly cross-reacted with the homologous proteins of S. cerevisiae. However, S. cerevisiae enolase and phosphoglycerate kinase did not cross-react with IgE of patient sera. This result suggests that IgE antibodies against only small parts of their epitopes are elevated in the allergic patients. Since enolase is reported to be a major antigen for systemic candidiasis, this enzyme may be the immunodominant protein in both allergies and fungal infections.
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PMID:Identification of Candida albicans antigens reactive with immunoglobulin E antibody of human sera. 154 78

Deoxyribose 5-phosphate aldolase was purified 41 times from Bacillus cereus induced by growth on deoxyribonucleosides. The purification procedure includes ammonium sulphate fractionation, gel filtration on Sephadex G-100, ion-exchange chromatography on DEAE-Sephacel and preparative electrophoresis on 10% polyacrylamide gel. The enzyme is stable above pH 6.5, but is rapidly inactivated by sulfhydryl reagents. Being insensitive to EDTA, it may be considered as a Class I aldolase. Among a number of compounds tested (including some carboxylic acids, free and phosphorylated pentoses, nucleotides and nucleosides), none has been found to affect the enzyme activity. The enzyme appears to be dimeric, with a subunit Mr of 23,600. A Km of 4.4 x 10(-4) M was calculated for dRib 5-P.
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PMID:Deoxyribose 5-phosphate aldolase of Bacillus cereus: purification and properties. 173 28

1. Aldolases were isolated from the ordinary muscle of red sea bream Pagrus major, Pacific mackerel Scomber japonicus, and carp Cyprinus carpio by ammonium sulfate fractionation, followed by ion-exchange chromatography on DEAE-cellulose and CM-Sepharose CL-6B columns, and examined for enzymatic properties. 2. The aldolases showed the highest activity in a pH range from 6.8-7.8 Km values for fructose-1,6-bisphosphate ranged from 0.025-0.10 mM. 3. Irrespective of fish species, aldolase activity was inhibited by ATP, ADP, and AMP. ATP showed the strongest inhibition and was competitive with fructose-1,6-bisphosphate. 4. The aldolases did not require divalent metal ions for activation and were completely inhibited at 0.1 mM Cu2+. 5. Thermal inactivation of the enzymes was of the first-order reaction. Red sea bream, Pacific mackerel and carp enzymes lost the activity by 50% when incubated at 50 degrees C for 8, 14 and 23 min, respectively.
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PMID:Enzymatic properties of fish muscle aldolase. 292 47

We have developed a method for the simultaneous purification of hexokinase, glucosephosphate isomerase, phosphofructokinase, fructose-1,6-bisphosphate aldolase, triosephosphate isomerase, D-glyceraldehyde-phosphate dehydrogenase, phosphoglycerate kinase, glycerol-3-phosphate dehydrogenase and glycerol kinase from Trypanosoma brucei in yields varying over 8-55%. Crude glycosomes were prepared by differential centrifugation of cell homogenates. Subsequent hydrophobic interaction chromatography on phenyl-Sepharose resulted in six pools containing various mixtures of enzymes. These pools were processed via affinity chromatography (immobilized ATP), hydrophobic interaction chromatography (octyl-Sepharose) and ion-exchange chromatography (CM- and DEAE-cellulose) which resulted in the purification of all nine enzymes. The native enzyme and subunit molecular masses, as determined by gel filtration and gel electrophoresis under denaturing conditions, were compared with those of their homologous counterparts from other organisms. Trypanosomal hexokinase is a hexamer and differs in subunit composition from the mammalian enzymes (monomers) as well as in subunit size (51 kDa versus 96-100 kDa, respectively). Phosphofructokinase only differs in subunit size (51 kDa for T. brucei versus 80-90 kDa for mammals) but had identical subunit composition (tetrameric). The others all have the same subunit composition as their mammalian counterparts. Except for triosephosphate isomerase, all Trypanosoma enzymes have subunits which are 1-5 kDa larger in size. Together these nine enzymes contribute 3.3 +/- 1.6% to the total cellular protein of T. brucei and at least 90% to the total glycosomal protein. A comparison of calculated intraglycosomal concentrations of the enzymes with the glycosomal metabolite concentrations shows that in the case of aldolase, glyceraldehyde-phosphate dehydrogenase and phosphoglycerate kinase, the concentration of active sites is of the same order of magnitude as that of their reactants. A common feature of the glycosomal glycolytic enzymes (with the exception of glucosephosphate isomerase) is that they are highly basic proteins with pI values between 8.8 and 10.2, values which are 1-4 higher than in the case of their mammalian cytosolic counterparts and 3-6 higher than in the case of the various unicellular organisms. It is suggested that both the larger subunit size and the basic character of the T. brucei glycolytic proteins are involved in the routing of the enzymes from their site of biogenesis (the cytosol) towards their site of action (the glycosome).
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PMID:Glycolytic enzymes of Trypanosoma brucei. Simultaneous purification, intraglycosomal concentrations and physical properties. 294 90

A human hybridoma clone (4E3) has been established by fusing lymphocytes from a lymph node taken from a breast cancer patient and human lymphoblastoid cells, LICR-LON-HMy2, by the poly(ethylene glycol) method. 4E3 has been stabilized and continued to secrete IgMk antibody into culture medium (greater than 10 micrograms/ml) for over 1 year. The following characteristics of the antigen strongly suggested that 4E3 recognizes liver-type aldolase B (EC 4.1.2.13): the Mr of the native molecule is 160,000 and that of the subunit is 40,000, and thus it has a tetrameric structure of identical subunits; the antigen is abundant in the liver and kidney of human, mouse and rabbit, and is localized by immunohistochemical methods in the cytoplasm of hepatocytes and in the proximal tubules of the kidney; the antigen is precipitable by 50-80% saturation with (NH4)2SO4; the antigen shows charge-dependent heterogeneity on DEAE-cellulose chromatography. To confirm this notion, aldolase B was purified to homogeneity from the liver of human, mouse and rabbit by phosphocellulose chromatography. During the chromatographic purification, the antigen activity as assayed by enzyme-linked immunosorbent assay (e.l.i.s.a.) was superimposed on the enzymic activity of aldolase. Furthermore, monoclonal antibody 4E3 strongly reacted with purified aldolase B in SDS/polyacrylamide-gel electrophoresis followed by Western blotting and also in e.l.i.s.a. using microplates coated with purified enzyme. The reaction between aldolase B and 4E3 activated the human complement system as assessed by the attachment of C3 to the immune complex of aldolase B and 4E3.
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PMID:Human monoclonal antibody recognizing liver-type aldolase B. 382 73

Two fructose diphosphate aldolases (EC 4.1.2.13) were detected in extracts of Escherichia coli (Crookes' strain) grown on pyruvate or lactate. The two enzymes can be resolved by chromatography on DEAE-cellulose at pH7.5, or by gel filtration on Sephadex G-200, and both have been obtained in a pure state. One is a typical bacterial aldolase (class II) in that it is strongly inhibited by metal-chelating agents and is reactivated by bivalent metal ions, e.g. Ca(2+), Zn(2+). It is a dimer with a molecular weight of approx. 70000, and the K(m) value for fructose diphosphate is about 0.85mm. The other aldolase is not dependent on metal ions for its activity, but is inhibited by reduction with NaBH(4) in the presence of substrate. The K(m) value for fructose diphosphate is about 20mum (although the Lineweaver-Burk plot is not linear) and the enzyme is probably a tetramer with molecular weight approx. 140000. It has been crystallized. On the basis of these properties it is tentatively assigned to class I. The appearance of a class I aldolase in bacteria was unexpected, and its synthesis in E. coli is apparently favoured by conditions of gluconeogenesis. Only aldolase of class II was found in E. coli that had been grown on glucose. The significance of these results for the evolution of fructose diphosphate aldolases is briefly discussed.
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PMID:Purification and characterization of two fructose diphosphate aldolases from Escherichia coli (Crookes' strain). 419 24


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