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Selective adsorption of heterophile polyglycerophosphate antigen from antigen extracts of Streptococcus mutans and other gram-positive bacteria.

Hamada, S; Tai, S; Slade, H D
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1976 EN
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Hot saline extracts of Streptococcus mutans have been shown to contain antigenic substances which occasionally react nonspecifically with some antisera against whole cells of various serological groups and types of streptococci. Chromatography of the extract of S. mutans strain MT703 (serotype e) on a diethylaminoethyl-Sephadex A-25 column gave two principal antigens. One antigen was eluted without adsorption to the resin and was identified as the serotype-specific polysaccharide. The other antigen, which contained a large quantity of phosphorus, was absorbed to and released from the resin by gradient elution. It was reactive against the antisera specific for polyglycerophosphate (PGP) from group A Streptococcus pyogenes and/or S. mutans strain Ingbritt (type c). The PGP antigen was further purified by gel filtration with Sephadex G-75. Two peaks, PGP-1, and PGP-2, were obtained. Each possessed the same antigenic specificity to anti-PGP serum as shown by immunodiffusion. Chemical analyses revealed that the molar ratio of phosphorus to glycerol in both was about 1:1, although the protein content between the two was significantly different. PGP antigen was found to be widely distributed in hot saline extracts from various gram-positive bacteria...

Separation of Soluble Brucella Antigens by Gel-Filtration Chromatography

McGhee, Jerry R.; Freeman, Bob A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1970 EN
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Soluble precipitating antigens of Brucella suis have been, in various degrees, purified by filtration on Sephadex gels. The most useful gels employed were Sephadex G-150, Sephadex G-200, and Sepharose 4B. Although not all fractions proved to be immunologically pure, some crude molecular-size estimates of most of the 13 soluble antigens of the Brucella cell could be given. In addition, monospecific antisera to three purified Brucella antigens have been prepared. By using purified preparations, physical and chemical data were obtained on two major antigens, E and 1, and a minor antigen, f. Antigen E is not an agglutinogen and may be toxic. Antigen 1 is of low molecular weight and is neither toxic nor agglutinogenic. The minor antigen f is an agglutinogen as well as a precipitinogen and is found on the cell surface. Both major antigens, when purified, were immunogenic in rabbits.

Extracellular Antigens from Listeria monocytogenes I. Purification and Resolution of Hemolytic and Lipolytic Antigens from Culture Filtrates of Listeria monocytogenes

Jenkins, E. M.; Watson, B. B.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/1971 EN
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Two antigens were purified from culture filtrates of Listeria monocytogenes 7973 by the following procedure: (i) acid precipitation with 4 n HCl at pH 3.7, (ii) Sephadex G-75 column fractionation, (iii) diethylaminoethyl-Sephadex A50 batchwise adsorption, and (iv) rechromatography on Sephadex G-75. This procedure resulted in the resolution of two distinct antigens. One antigen, designated a hemolytic antigen because of its ability to lyse erythrocytes from a variety of species, had a specific activity of 25,000 units/mg of protein and an estimated molecular weight of at least 171,000. The other antigen, designated a lipolytic antigen because of its ability to hydrolyze egg yolk saline substrate, had a specific activity of 400 units/mg of protein and an estimated molecular weight of 52,500.

Chemical and immunological properties of the type f polysaccharide antigen of Streptococcus mutans.

Hamada, S; Gill, K; Slade, H D
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1976 EN
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The type-specific cell wall polysaccharide antigen was extracted, purified, and characterized from type f Streptococcus mutans strain OMZ175 and MT557. The antigen was extracted from lyophilized cells with 5% trichloroacetic acid at 85 C for 15 min or saline at 120 C for 30 min. The trichloroacetic acid antigen was chromatographically separated into three antigenic fractions on a diethylaminoethyl-Sephadex A-25 column. Antigen 1 (Ag1P), which was specific for type f antiserum, was further purified by passing through carboxymethyl-Sephadex C-25 and Sephadex G-200 columns. It was a polysaccharide composed of 49% rhamnose and 47% glucose. No reaction was obtained with anti-polyglycerophosphate (PGP) serum. Antigen 2 was reactive with both type f and PGP antisera and contained significant amounts of protein and phosphorus. Antigen 3 was reactive only with PGP antiserum and had no type specificity. The polysaccharide antigen gave a single precipitin band against type-specific antiserum on immunodiffusion and immunoelectrophoresis. The presence of alpha-1,6-glucosidic linkages was indicated by a 90% inhibition of the precipitin reaction by isomaltose and alpha-methyl-D-glucopyranoside, adsorption to and release from a concanavalin A-Sepharose column...

Isolation of a Plant Glycoprotein Involved with Control of Intercellular Recognition 1

Ferrari, Thomas E.; Bruns, Diane; Wallace, Donald H.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1981 EN
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A recognition molecule was isolated from stigmas of S-allele genotype S2S2 of Brassica oleracea var. capitata L. After Sephadex chromatography, it eluted as a single symmetrical peak during diethylaminoethane-cellulose chromatography. A high degree of purity was affirmed by: sedimentation as a single peak during ultracentrifugation through 5 to 20% sucrose gradients; elution as a single peak from Sephadex G-100; visualization as a single band which stains with Coomassie blue and periodic acid Schiff reagent after electrophoresis on polyacrylamide gels. Other criteria supporting the conclusion that it is a glycoprotein are: (a) the highly purified preparation is anthrone-positive and has a Lowry protein to anthrone-positive carbohydrate ratio of 1.3; (b) the preparation contains arabinose, galactose, glucose, and mannose, although it is not precipitated by concanavalin A; (c) the immunological properties of the molecule are lost following protease treatment, and it has a molecular weight of 90,000 by Sephadex gel-filtration analysis and 54,500 by velocity sedimentation analysis.

Studies on the Pectic Substances of Plant Cell Walls: III. DEGRADATION OF CARROT ROOT CELL WALLS BY ENDOPECTATE LYASE PURIFIED FROM ERWINIA AROIDEAE

Konno, Haruyoshi; Yamasaki, Yoshiki
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/1982 EN
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Pectate lyase was isolated from the cell extract of Erwinia aroideae. The enzyme was further purified to a high degree by a procedure involving ammonium sulfate fractionation and chromatography on CM-Sephadex C-50 and on Sephadex G-200. The enzyme attacked its substrate in an endo fashion and was more active on the sodium salt of acid-insoluble polygalacturonate or pectic acid than it was on the methoxylated pectin. The enzyme had an optimum pH at 9.3, was stimulated by calcium ions, and was completely inhibited by ethylenediaminetetraacetic acid. In addition, the reaction products showed an absorption maximum between 230 and 235 nm and reacted with thiobarbituric acid. These results indicate that the purified enzyme is an endopectate lyase. The endopectate lyase also had the ability to solubilize effectively the pectic fraction from the cell walls of carrot (Daucus carota) root tissue. The enzyme released 30.5% of the wall as soluble products and also liberated all of the galacturonic acid present in the walls. The total neutral sugars released by the enzyme were 10.6% of the walls, which corresponded to 71.5% of noncellulosic neutral sugars. The soluble products were separated into five fractions by DEAE-Sephadex A-50 column chromatography. Based on the analysis of sugar composition of each fraction...

Purification and synthesis of eosinophilotactic tetrapeptides of human lung tissue: identification as eosinophil chemotactic factor of anaphylaxis.

Goetzl, E J; Austen, K F
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1975 EN
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Preferential eosinophil chemotactic activity exhibiting a molecular weight comparable to that released from sensitized human lung fragments challenged with specific antigen and designated eosinophil chemotactic factor of anaphylaxis has been isolated from extracts of human lung fragments by sequential purification on Sephadex G-25, Dowex-1, Sephadex G-10, and paper chromatography. Two eosinophilotactic tetrapeptides of amino acid sequence Val-Gly-Ser-Glu and Ala-Gly-Ser-Glu were recovered from the extracts in 4-12% overall yield of the low molecular weight peak from Sephadex G-25. Purified eosinophil chemotactic factor of anaphylaxis and the synthetic tetrapeptides were maximally active in amounts from 0.1 to 1.0 nmol per chemotactic chamber, and the activity was dependent on both the NH2-terminal and the COOH-terminal residues. Both natural and synthetic peptides were preferentially chemotactic for eosinophils and rendered them unresponsive to a subsequent stimulus.

Phosphoprotein Phosphatase of Soybean Hypocotyls: PURIFICATION, PROPERTIES, AND SUBSTRATE SPECIFICITIES 1, 2

Lin, Paul P.-C.; Mori, Tokunori; Key, Joe L.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1980 EN
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A soybean histone-type protein kinase was used to prepare 32P-labeled histone H1 as substrate for purification and characterization of a phosphoprotein phosphatase (EC 3.1.3.16) from soybean hypocotyls. The phosphatase has been purified 169-fold by ammonium sulfate fractionation, ethanol precipitation, and chromatography on Sephadex G-150, DEAE-Sephadex A-25 and Sephadex G-100. The activity of the phosphoprotein phosphatase is distinct from that of acid and alkaline phosphatases (EC 3.1.3.1) as well as from that of nucleotidases. The final enzyme preparation does not contain histone protease activity, although it can be detected during the early stages of purification. The protease(s) apparently can attack phosphorylated histone H1, indicating that phosphorylation does not protect the protein against proteolytic degradation.

Preparation and Properties of Thyroxine-Binding Alpha Globulin (TBG)

Sterling, Kenneth; Hamada, Satoshi; Takemura, Yoshihiro; Brenner, Milton A.; Newman, Edward S.; Inada, Mitsuo
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1971 EN
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Thyroxine-binding alpha globulin (TBG) in human serum was isolated from Cohn fractions IV-5,6 and IV-4 by (1) chromatography on carboxymethyl (CM) cellulose, (2) gel filtration on Sephadex G-200, (3) chromatography on diethylaminoethyl-Sephadex, (4) a novel procedure of “double-gel” electrophoresis, and (5) preparative polyacrylamide gel electrophoresis. The protein was homogeneous by analytical disc gel electrophoresis, immunoelectrophoresis, and ultracentrifugal analyses (sedimentation velocity and sedimentation equilibrium), and after addition of thyroxine-125I showed a constant specific radioactivity on polyacrylamide electrophoresis. The sedimentation and diffusion coefficients were s20, w, 3.0 × 10−13 sec, and D20, w, 8.05 × 10−7 cm2·sec−1, and the molecular weight obtained by sedimentation equilibrium was 36,500. Gel filtration studies on Sephadex G-200 demonstrated that the protein had the same elution volume as that of native TBG in serum, apparently excluding the possibility of a subunit of the native protein. Chemical composition was ascertained by amino acid and carbohydrate analyses. The maximal thyroxine (T4)-binding capacity measured by reverse flow paper electrophoresis was 15,000 μg per g of protein, representing more than 2100 times that of the starting material...

Radioiodination of human intrinsic factor

Mackenzie, Iain L.; Donaldson, Robert M.; Schilling, Robert F.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1969 EN
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Human intrinsic factor (IF) saturated with 60Co-labeled cyanocobalamin (60CoB12) was purified and then iodinated with 125I to yield 125I-labeled IF-60CoB12 preparations of high specific activity. Sephadex G200 and DEAE-cellulose chromatography of the iodinated IF-60CoB12 complex showed coincidence of the major 125I and the 60Co radioactivity peaks. During starch-gel electrophoresis 60Co radioactivity from noniodinated and iodinated complexes migrated to the same extent while 125I radioactivity from the iodinated complex migrated slightly further anodally than did the 60Co radioactivity. After the iodinated complex was mixed with antibody to the IF-B12 complex (antibody II) the 125I and 60Co radioactivity were: (a) precipitated in similar amounts by antiglobulin serum. (b) eluted coincidentally in the 19S region on Sephadex G200, and (c) excluded to the same extent from starch gel during electrophoresis. After equilibrium exchange of IF “blocking” antibody (antibody I) for 60Co-vitamin B12 on 125I-labeled IF. 125I radioactivity from the IF-antibody I complex: (a) was precipitated by antiglobulin serum, (b) was eluated in the 19S region on Sephadex G200 gel filtration, and (c) migrated slowly towards the anode on starch-gel electrophoresis. Urinary excretion of 60Co radioactivity in pernicious anemia patients after oral administration of 60Co-vitamin B12 bound to freshly prepared 125I-labeled IF was similar to that obtained with noniodinated intrinsic factor.

In Vitro Stability of Nitrate Reductase from Wheat Leaves: III. Isolation and Partial Characterization of a Nitrate Reductase-inactivating Factor 1

Sherrard, Joseph H.; Kennedy, Jillian A.; Dalling, Michael J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1979 EN
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A nitrate reductase (EC 1.6.6.1)-inactivating factor has been isolated from 8-day-old wheat leaves. The purification schedule involved ammonium sulfate precipitation, Sephadex G-100 filtration, DEAE-cellulose chromatography, and Sephadex G-150 filtration. No accurate assessment could be made as to the degree of purification relative to crude extract as the inactivating factor could not be detected in crude extract. However a 2,446-fold purification was achieved from the ammonium sulfate fraction to the pooled enzyme from the Sephadex G-150 step.

Amylases from Aleurone Layers and Starchy Endosperm of Barley Seeds

Bilderback, D. E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1974 EN
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Amylases from incubated aleurone layers or from starchy endosperm of barley seeds (Hordeum vulgare L. cv. Himalaya) were investigated using acrylamide gel electrophoresis and analytical gel filtration with Sephadex G-200. Electrophoresis of amylase from aleurone layers yields seven visually distinct isozymes with an estimated molecular weight of 43,000. Because each isozyme hydrolyzes β-limit dextrin azure and incorporates calcium-45, they are α-amylases. On Sephadex G-200, amylase from the aleurone layers is separated into seven fractions ranging in estimated molecular weights from 45,000 to 3,000. Little or no activity is observed when six fractions are subjected to electrophoresis. Electrophoresis of only the fraction with the estimated molecular weight of 45,000 gave the seven isozymes. The amylases are heat labile and cannot be stabilized by the presence of substrate or by the protease inhibitor, phenylmethylsulfonylfluoride. Electrophoresis of amylase from the starchy endosperm yields nine β-amylases. Four of these β-amylases are isozymes with an estimated molecular weight of 43,000. The other five forms of β-amylase represent molecular aggregates of the four basic β-amylase monomers. A dimer, a tetramer, and an octamer of β-amylase can be identified with estimated molecular weights of about 86...

Enhancement of urate solubility by connective tissue. II. Inhibition of sodium urate crystallisation by cation exchange.

Perricone, E; Brandt, K D
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1979 EN
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The urate concentration of the supernatant was greater after supersaturated solutions of sodium urate were incubated in a suspension of CM-Sephadex C-25 than in one of Sephadex G-25. The supernatant urate concentration was greater when the CM-Sephadex had been equilibrated with potassium than with sodium. The results are analogous with those obtained in studies of urate solubility in proteoglycan solutions. They are consistent with the Donnan effect and the hypothesis that the glycosaminoglycans within the proteoglycan molecule function as cation exchangers which, when charged with potassium, exchange with the sodium of the urate molecule, leading to formation of highly soluble potassium urate.

Cytokinin Production by Bradyrhizobium japonicum1

Sturtevant, Dawn B.; Taller, Barbara J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/1989 EN
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Although there is considerable circumstantial evidence for the involvement of cytokinins in legume nodulation, the cytokinins produced by rhizobia have not been well characterized. Bradyrhizobium japonicum 61A68, a bacterium which nodulates soybean (Glycine max [L.] Merr.), was grown in defined medium. Cytokinins were purified from the culture medium by Amberlite XAD-2 chromatography and fractionated by column chromatography on Sephadex LH-20 in 35% ethanol. Pooled fractions from the Sephadex column were analyzed for cytokinin activity with the tobacco callus bioassay. Cytokinin activity was observed in fractions corresponding to the elution volumes of zeatin, ribosylzeatin, and methylthiozeatin. No activity corresponding to the elution volumes of isopentenyladenine or its riboside was found. Total cytokinin activity in the B. japonicum culture filtrate was equivalent to approximately 1 microgram of kinetin per liter. Transfer RNA was isolated from B. japonicum cells by phenol extraction, followed by potassium acetate extraction, cetyltrimethylammonium bromide precipitation, and DEAE cellulose chromatography. Transfer RNA was enzymically hydrolyzed to nucleosides. High performance liquid chromatographic analysis of cytokinin nucleosides showed peaks corresponding to the retention times of trans-ribosylzeatin...

Invertase Inhibitor from Potatoes: Purification, Characterization, and Reactivity with Plant Invertases

Pressey, Russell
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1967 EN
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Invertase inhibitor was extracted from potato tubers and purified nearly 1000-fold. The purification procedure involved precipitation at pH 4.0, fractionation with ammonium sulfate, adsorption on alumina Cγ gel, and gel filtration on Sephadex G-100 and DEAE-Sephadex A-50. The product obtained was homogeneous to electrophoresis on polyacrylamide gel. Exclusion chromatography on Sephadex G-100 indicated a molecular weight of about 17,000. The inhibitor did not inhibit yeast, Neurospora, and several plant invertases. It completely inhibited potato tuber invertase and a number of other plant invertases. Some plant invertases were partially inhibited.

Purification and N-terminal partial sequence of anti-epilepsy peptide from venom of the scorpion Buthus martensii Karsch.

Zhou, X H; Yang, D; Zhang, J H; Liu, C M; Lei, K J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/01/1989 EN
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An anti-epilepsy peptide (AEP) was isolated and purified from venom of the scorpion Buthus martensii Karsch. The purification procedure included CM-Sephadex C-50 chromatography, gel filtration on Sephadex G-50 and DEAE-Sephadex A-50 chromatography. Its homogeneity was demonstrated by pH 4.3 polyacrylamide-disc-gel electrophoresis, focusing electrophoresis and SDS/polyacrylamide-disc-gel electrophoresis. The Mr of this peptide, calculated from measurements in SDS/15%-polyacrylamide-disc-gel and SDS/20%-polyacrylamide-disc-gel electrophoresis, is 8300. The isoelectric point is 8.52 by pH 8-9.5-range isoelectric focusing. No haemorrhagic or toxic activities were found. No toxicity was found even after the dose reached 28 mg/kg. The pharmacological tests showed that the AEP had no effect on heart rate, blood pressure or electrocardiogram, but strongly inhibited epilepsy induced by coriaria lactone and cephaloridine. The fluorescence spectrum showed that the peptide has a strong emission peak at 337 nm. Amino acid analysis suggested that the AEP is composed of 66 residues from 18 amino acids and has an Mr of 8290. The sequence of the first 50 N-terminal residues is as follows: Asp-Gly-Tyr-Ile-Arg-Gly-Ser-Asp-Asn-Cys-Lys-Val-Ser-Cys-Leu-Leu-Gly-Asn- Glu-Gly - Cys-Asn-Lys-Glu-Cys-Arg-Ala-Tyr-Gly-Ala-Ser-Tyr-Gly-Tyr-Cys-Trp-Thr-Val- Lys-Leu - Ala-Gln-Asp-Cys-Glu-Gly-Leu-Pro-Asp-Thr-.

An anti-neoplastic glycan isolated from Mycobacterium bovis (BCG vaccine).

Wang, R; Klegerman, M E; Marsden, I; Sinnott, M; Groves, M J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/11/1995 EN
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Tice substrain BCG is used clinically as an immunotherapeutic agent against superficial bladder cancer. A boiling-water extract of this BCG showed anti-tumour activity against a murine S180 sarcoma model and was fractionated into three fractions, A, B and C, by the use of Sephadex LH-20 chromatography. An anti-tumour glucan, PS1A1, was isolated from fraction PS1A with Sephadex G-75. The molecular mass of PS1A1 was between 65 and 87 kDa by Sephadex G-100 chromatography. The structure of PS1A1 was investigated by one- and two-dimensional NMR spectroscopy and methylation analysis and was demonstrated to be primarily 1-->6-alpha-linked glucose units. We postulate that the repeating unit is: [Formula: see text]

Purification and characterization of glutathione-dependent dehydroascorbate reductase from rat liver.

Maellaro, E; Del Bello, B; Sugherini, L; Santucci, A; Comporti, M; Casini, A F
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/07/1994 EN
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GSH-dependent enzymic reduction of dehydroascorbic acid to ascorbic acid has been studied in rat liver cytosol. After gel filtration of cytosol on Sephadex G-100 SF, dehydroascorbate reductase activity was recovered in two distinct peaks, one corresponding to glutaredoxin (an enzyme already known for its dehydroascorbate reductase activity) and another, much larger one, corresponding to a novel enzyme different from glutaredoxin. The latter was purified to apparent homogeneity. The purification process involved (NH4)2SO4 fractionation, followed by DEAE-Sepharose, Sephadex G-100 SF and Reactive Red chromatography. SDS/PAGE of the purified enzyme in either the presence or absence of 2-mercaptoethanol demonstrated a single protein band of M(r) 31,000. The M(r) determined by both Sephadex G-100 SF chromatography and h.p.l.c. was found to be approx. 48,000. H.p.l.c. of the denatured enzyme gave an M(r) value identical with that obtained by SDS/PAGE (31,000). The apparent Km for dehydroascorbate was 245 microM and the Vmax. was 1.9 mumol/min per mg of protein; for GSH they were 2.8 mM and 4.5 mumol/min per mg of protein respectively. The optimal pH range was 7.5-8.0. Microsequence analysis of the electro-transferred enzyme band showed that the N-terminus is blocked. Data on internal primary structure were obtained from CNBr-and N-chlorosuccinimide-derived fragments. No significative sequence similarity was found to any of the protein sequences contained in the Protein Identification Resource database.

Purification and characterization of a tartrate-resistant acid phosphatase from human osteoclastomas.

Hayman, A R; Warburton, M J; Pringle, J A; Coles, B; Chambers, T J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/07/1989 EN
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Tartrate-resistant acid phosphatase is one of the major enzymes produced and secreted by osteoclasts. To obtain sufficient enzyme for biochemical characterization, we have purified this enzyme from human osteoclastomas by sequential chromatography on SP-Sephadex, CM-Sephadex, hydroxylapatite, Sephadex G-150 and concanavalin A-Sepharose. The purification over the original tumour extract was about 2000-fold, with a yield of 10%. The enzyme appeared to be homogeneous when assessed by SDS/polyacrylamide-gel electrophoresis. Both gel filtration and SDS/polyacrylamide-gel electrophoresis indicated an Mr of about 30,000. The reduced and alkylated enzyme consists of two subunits with Mrs of 15,000 and 17,500. The N-terminal amino acid sequence of both subunits indicates that there is a high degree of identity between the osteoclastoma enzyme and similar enzymes purified from spleen and uterus. Using 4-methylumbelliferyl phosphate as substrate, the specific activity of the purified enzyme was 387 units.mg-1, and the Km was 284 microns. The pH optimum was 5.7. Unlike similar enzymes purified from human and bovine bone, osteoclastoma acid phosphatase is not activated by reducing agents (2-mercaptoethanol or ascorbic acid). The enzyme contains 4.8 mol of Fe2+/3+...

Specific and non-specific folate binding protein in normal and malignant human tissues

Corrocher, R.; De Sandre, G.; Ambrosetti, A.; Pachor, M. L.; Bambara, L. M.; Hoffbrand, A. V.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1978 EN
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Binding of tritiated folic acid by supernatants prepared from extracts of normal and leukaemic leucocytes, normal mucosa, and malignant tumours from different parts of the gastrointestinal tract has been measured using Sephadex-gel filtration and albumin-coated charcoal techniques. Non-specific binding (measured by Sephadex G-75 gel filtration) was almost invariably greater than specific binding measured by albumin-coated charcoal separation of bound and unbound folate. In nine normal leucocyte extracts, binding measured by Sephadex G-75 filtration ranged from 1·3 to 18·2 (mean 8·2) pg/mg protein and by albumin-coated charcoal from 1·0 to 14·8 (mean 6·7) pg/mg protein. Raised specific binding was found in the extracts from leucocytes of eight of 14 patients with chronic granulocytic leukaemia, in four substantially so (389, 121, 108, 59·7 pg/mg protein), but was only marginally increased in one of eight cases of acute myeloid leukaemia and in two of five cases of chronic lymphocytic leukaemia. Binding was normal in the extracts of all three cases of acute lymphoblastic leukaemia tested.