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1.
A simple method, involving NAD+-Sepharose chromatography, was developed for the preparation of snake venom phosphodiesterase (EC 3.1.4.1) almost free from 5'-Nucleotidase (EC 3.1.3.5). Using an NAD+-Sepharose 4B column, phosphodiesterase was eluted in the unadsorbed fraction, whereas 5'nucleotidase was strongly adsorbed. The latter enzyme was desorbed when 0.2 M sodium bicarbonate buffer containing 1mM beta-NADH was used as a solvent. The affinity column could be used at least four times without any decrease of potency, and the method was applicable for the preparation of phosphodiesterase from the venoms of rattlesnake (Crotalus adamanteus) and Japanese mamushi (Agkistrodan halys blomhoffi).  相似文献   

2.
A method for purifying the platelet membrane glycoprotein IIb-IIIa complex   总被引:8,自引:0,他引:8  
A method has been developed for the rapid isolation of platelet membrane glycoproteins (GP) IIb and IIIa. This method produces an excellent yield and does not require the prior isolation of platelet membranes. Outdated platelets were washed and solubilized in Triton X-100. Concanavalin A affinity chromatography was used to purify a platelet glycoprotein fraction. The concanavalin A-retained glycoproteins were eluted and adsorbed with a heparin-Sepharose column to remove a major contaminant, thrombospondin. Sephacryl S-300 gel filtration was used as the final purification step to remove most fibrinogen and low-molecular-weight contaminants. Wheat germ agglutinin affinity chromatography was used to completely remove trace amounts of fibrinogen. The purified GP IIb and GP IIIa were analyzed by sucrose gradient sedimentation and found to consist of heterodimer complexes.  相似文献   

3.
Homologous whole histone from calf thymus was adsorbed on Sepharose 4B columns with covalently coupled histone fractions H2a, H2b, H3 or H4 in 0.01 M phosphate buffer, pH 6.7–1 M NaCl. The adsorbed histones were eluted from the columns with 5 M urea in the same buffer. Electrophoretic analysis has shown that the different columns exhibit selective affinity to the histone fractions: the H2b column to histone H2b and H2a (with only weak affinity to histones H3 and H4), the H2a column to histones H2b and H3 (moderate affinity to histones H2a and H4), the H3 column to histones H3, H4, H2a (moderate affinity to histone H2b), and the H4 column to histone H3, H4 and H2b (weak affinity to histone H2a). Histone H1 displayed no fixation by either of the columns tested.  相似文献   

4.
Purification of thiamine-binding protein from Escherichia coli   总被引:2,自引:0,他引:2  
An affinity column coupled with thiamine pyrophosphate quantitatively absorbs the thiamine-binding activity from a partially purified preparation of Escherichiacoli. The thiamine-binding protein can be eluted from the affinity column in high yield by use of 8 M urea-containing buffer. Approximately 90-fold purification occurs by affinity chromatography yielding a preparation which appears to be homogenous.  相似文献   

5.
A simple purification procedure for raw starch-adsorbable and -digesting amylases (RSAs) was devised. The method depended on an affinity column, which was prepared by mixing raw corn starch and Hyflo Super-Cel. RSAs were specifically adsorbed on the matrix, and eluted with a buffer containing 1% β-cyclodextrin. This column could be used to purify RSAs from Streptomyces thermo-cyaneoviolaceus and a recombinant strain of E. coli.  相似文献   

6.
During affinity chromatography on N-(epsilon-aminocaproyl)-beta-L-fucopyranosylaminosepharose of the enzyme preparation of alpha-L-fucosidase from human kidney the elution profile of the enzyme revealed two components, which can be designated as alpha-L-fucosidases A and B. In the absence of sodium aside in the buffer mixtures used one of the components (fucosidase A) was retained by an affinity adsorbent, while the other one (fucosidase B) was adsorbed under the same conditions; the latter component was eluted with a solution containing the enzyme inhibitor--L-fucose. Data from the enzyme rechromatography suggest an equilibrium of the fucosidases A and B, which differ in their affinities for the affinity sorbent.  相似文献   

7.
ω-Aminohexyl-Sepharose 4B served as an excellent biospecific adsorbent for affinity chromatography of amine oxidase (monoamine:O2 oxidoreductase (deaminating), EC 1.4.3.4) from Aspergillus niger. The enzyme was completely adsorbed on this affinity resin when applied to a column in 0.1 M potassium phosphate buffer (pH 7.2). Although a small part of the enzyme was retained on the column through ionic interaction and eluted with 1.0 M potassium phosphate buffer (pH 7.2), most of the enzyme adsorbed was eluted with 0.5 M potassium phosphate buffer (pH 7.2) containing 10 mM butylamine. Essentially no retention of the enzyme on a column of ε-aminopentyl-Sepharose or δ-aminobutyl-Sepharose occurred under the same conditions, indicating that an appropriate length (more than approx. 12 Å) of a hydrocarbon extension between the agarose matrix and the terminal amino group would be necessary for efficient adsorption of amine oxidase. The modification of the enzyme with 3-methyl-2-benzothiazolinone hydrazone (carbonyl inhibitor) or dithionite (reducing agent) resulted in loss of the ability to bind to ω-aminohexyl-Sepharose. I was also demonstrated that the affinity chromatography on ω-aminohexyl-Sepharose can be used as a powerful means of purifying this enzyme from crude extracts of Aspergillus niger. All of the three adsorbents were effective as a substrate in the amine oxidase reaction, but their substrate activities were as low as the corresponding free diamines.  相似文献   

8.
1. A gingival epithelial cell surface receptor for laminin was isolated from bovine gingival tissue by affinity chromatography on laminin. 2. The protein bound by the affinity matrix from octylglucoside extracts of gingival membrane preparation eluted from the column with the cation-free buffer containing EDTA, and exhibited a mol. wt of 67 kDa. 3. The 67 kDa protein following radioiodination was incorporated into liposomes, which showed a specific affinity towards laminin-coated surfaces, as well as to the tooth cementum. 4. The results provide for the first time evidence for the existence of a gingival cell surface laminin receptor, and indicate that the maintenance of the cemento-epithelial junction involves the interaction between the cementum laminin and its receptor on gingival epithelium.  相似文献   

9.
Omega-Aminohexyl-Sepharose 4B served as an excellent biospecific adsorbent for affinity chromatography of amine oxidase (monoamine:O2 oxidoreductase (deaminating), EC 1.4.3.4) from Aspergillus niger. The enzyme was completely adsorbed on this affinity resin when applied to a column in 0.1 M potassium phosphate buffer (pH 7.2). Although a small part of the enzyme was retained on the column through ionic interaction and eluted with 1.0 M potassium phosphate buffer (pH 7.2), most of the enzyme adsorbed was eluted with 0.5 M potassium phosphate buffer (pH 7.2) containing 10 mM butylamine. Essentially no retention of the enzyme on a column of epsilon-aminopentyl-Sepharose or delta-aminobutyl-Sepharose occurred under the same conditions, indicating that an appropriate length (more than approx. 12 A) of a hydrocarbon extension between the agarose matrix and the terminal amino group would be necessary for efficient adsorption of amine oxidase. The modification of the enzyme with 3-methyl-2-benzothiazolinone hydrazone (carbonyl inhibitor) or dithionite (reducing agent) resulted in loss of the ability to bind to omega-aminohexyl-Sepharose. It was also demonstrated that the affinity chromatography on omega-aminohexyl-Sepharose can be used as a powerful means of purifying this enzyme from crude extracts of Aspergillus niger. All of the three adsorbents were effective as a substrate in the amine oxidase reaction, but their substrate activities were as low as the corresponding free diamines.  相似文献   

10.
The mitochondrial isoenzyme of creatine kinase (MiMi-CK) was separated by affinity chromatography on Cibachrome-Blue-Sepharose (Sepharose-Blue, Pharmacia). While the soluble CK isoforms (BB-CK and MM-CK) were specifically eluted by raising the pH of the column buffer from pH 6.0 to pH 8.0, MiMi-CK remained bound under these conditions but was specifically eluted by subsequent addition of ADP to the pH 8.0 buffer. This one-step method allows a fast and efficient separation of MiMi-CK from MM-and BB-CK isoenzymes and at the same time an enrichment of MiMi-CK by about 50-fold. Since MiMi-CK can be assayed separately after isolation by affinity chromatography on Sepharose-Blue, this method may be of clinical importance.  相似文献   

11.
Preparations of one-chain tissue plasminogen activator (tPA), usually a mixture of 65- and 63-kDa differentially glycosylated forms, contain variable amounts of two-chain tPA. There is no effective procedure currently available for removal of the two-chain contaminant from one-chain tPA preparations. In this report, affinity chromatography on benzamidine-Sepharose was investigated for the separation of two-chain from one-chain tPA. Activase, a preparation of recombinant tPA containing 80% one-chain tPA, a mixture of 65- and 63-kDa variants, and 20% two-chain tPA, was applied to a column of benzamidine-Sepharose, equilibrated with 1 M ammonium bicarbonate. Under this condition, both one-chain and two-chain forms of tPA were adsorbed by the column. Addition of 0.1 M arginine to the equilibration buffer led to elution of two-peaks, corresponding to the 65- and 63-kDa variants of one-chain tPA. Two-chain tPA remained bound to the column, but could be eluted with sodium acetate buffer, pH 4.0, containing 0.1 M arginine. The present procedure allows rapid and effective removal of two-chain tPA with concomitant separation of 65- and 63-kDa one-chain glycoforms from preparations of one-chain tPA. Kinetic analysis for the hydrolysis of D-Ile-Pro-Arg-p-nitroanilide (S-2288) by the highly purified molecular forms of tPA suggests that 63-kDa one-chain tPA possesses 30% higher catalytic efficiency than the 65-kDa variant, while two-chain tPA is 9- or 12-fold more efficient than 63- or 65-kDa one-chain tPA, respectively.  相似文献   

12.
A rapid procedure for the isolation of 3,4-dihydroxyphenylalanine-containing proteins has been developed in which the protein is selectively bound to a m-phenylboronate agarose column, and eluted with 1.0 M ammonium acetate, pH 3.0. The method is based on the affinity of boronates for diols including catechol. The chromatography is carried out in the absence of oxygen to prevent oxidation of the catechol. Other proteins are eluted beforehand with 0.25 M ammonium acetate, pH 8.5, or for glycoproteins with a Tris buffer containing 0.2 M sorbitol, pH 8.5.  相似文献   

13.
Lectin affinity chromatography was used to demonstrate that digitonin-solubilized opiate receptors contain a carbohydrate moiety. Receptors solubilized from toad, rat, chicken, bovine and human brains were retained on columns of wheat germ agglutinin (WGA)-agarose and eluted specifically with N-acetylglucosamine. The fraction retained and subsequently eluted ranged from 40–60% of the applied receptors. The eluted receptor was enriched approx. 30-fold. Evidence is presented which shows that the site of lectin interaction is functionally independent of the opiate binding site.  相似文献   

14.
Cytidinediphospho-sn-1,2-diaclglycerol (CDP-diglyceride) has been covalently linked to Sephrose 4B via adipic acid dihydrazide spacer arm forming an effective affinity chromatography column. This liponucleo-tide ligand and sn-glycero-3-phosphate are subtracts for the formation of 3-sn-phoshatidyl-1'-sn-glycero-3'-phosphate (PGP) catalyzed in both eukaryotic and prokaryotic organisms by sn-glycero-3-phosphate: CMP phosphatidlytranferase (PGP synthetase). Using this CDP-diglyceride Sephrose affinity column we were able to resolve the membrane associated 3-sn-phosphatidyl'1-sn-glycerol (PG) synthesizing system present in Bacillus licheniformis into two activities. A PGP synthetase activity was adsorbed to the affinity column and was eluted using buffer containg CDP-diglyceride; a PGP phosphatease acactivity had no affinity for the column. Both PGP synthase and PGP phosphatase of B. licheniformis were associated with a membrane component of the cell as evidenced by sucrose gradient centrifugation, differential centrifugation, and solubilization by buffers containing detergent...  相似文献   

15.
An affinity chromatography method for purification of β-amylase from cytoledons of whit mustard seedlings (Sinapsi alba L.) is described. β-Amylase is bound to starch column, while other contaminating proteins are eluted with the binding buffer. The bound β-amylase is eluted by including dextrin (1%, w/v) in binding buffer. This method yielded a homogenous preparation of β-amylase enzyme, which migrated as a single polypetide band in SDS electrophoresis.  相似文献   

16.
A simple and rapid affinity chromatographic method for the isolation of aspartate transcarbamylase from germinated seedlings of mung bean (Phaseolus aureus) was developed. A partially purified preparation of the enzyme was chromatographed on an affinity column containing aspartate linked to CNBr-activated Sepharose 4B. Aspartate transcarbamylase was specifically eluted from the column with 10 mm aspartate or 0.5 m KCl. The enzyme migrated as a single sharp band during disc electrophoresis at pH 8.6 on polyacrylamide gels. Electrophoresis of the sodium dodecyl sulfate-treated enzyme showed two distinct protein bands, suggesting that the mung bean aspartate transcarbamylase was made up of nonidentical subunits. Like the enzyme purified by conventional procedures, this enzyme preparation also exhibited positive homotropic interactions with carbamyl phosphate and negative heterotropic interactions with UMP. This method was extended to the purification of aspartate transcarbamylase from Lathyrus sativus, Eleucine coracona, and Trigonella foenum graecum.  相似文献   

17.
We have reported the solubilization of complexes between vasoactive intestinal peptide (VIP) and its receptor from rat liver in a GTP-sensitive form of Mr 150,000 [Couvineau, A., Amiranoff, B. & Laburthe, M. (1986) J. Biol. Chem. 261, 14482-14489]. In the present study, we demonstrate a stable association of solubilized VIP receptor and stimulatory guanine nucleotide-binding protein (Gs protein), taking advantage of the ability of the glycoproteic VIP receptor (Mr 48,000), and the inability of the Gs protein, to adsorb to wheat germ agglutinin (WGA). 125I-VIP-receptor complexes solubilized in Triton X-100 were adsorbed on WGA-Sepharose, extensively washed and the radioactivity retained was eluted with 1 mM GTP showing that: (a) radioactivity corresponds to free 125I-VIP and (b) alpha s (Mr 42,000) and beta (Mr 35,000) subunits of Gs protein are detectable in the GTP eluate by immunoblotting using antisera against these subunits. Such an effect of GTP implied that a stable ternary complex consisting of VIP, receptor and Gs protein had been adsorbed to WGA-Sepharose. When Triton-solubilized 125I-VIP-receptor complexes were adsorbed on WGA-Sepharose, then retained material was specifically eluted with 0.3 M N-acetylglucosamine, analysis of the sugar eluate showed the following results. (a) GTP induces the dissociation of 125I-VIP-receptor complexes of Mr 150,000 contained in the eluate indicating that 125I-VIP-receptor-G protein complexes had been adsorbed to the WGA column. (b) The Mr-42,000 alpha s subunit can be specifically ADP-ribosylated by cholera toxin. (c) Immunoblotting using antisera against the alpha s and beta subunits of Gs protein, reveals Mr-42,000 and Mr-35,000 components corresponding to alpha s and beta subunits, respectively. (d) Affinity cross-linking using dithiobis(succinimidyl-propionate) of 125-I-VIP-receptor complexes eluted from the WGA column reveals a major band corresponding to Mr 150,000. Immunoblotting using antisera against the beta-subunit shows the presence of the beta subunit (Mr 35,000) in this Mr-150,000 component. In conclusion, these data provide functional and immunochemical evidence for the physical association of solubilized VIP-receptor complexes with alpha s and beta subunits of Gs protein.  相似文献   

18.
Solubilization and partial purification of GABAB receptor from bovine brain   总被引:1,自引:0,他引:1  
gamma-Aminobutyric acid (GABA)B receptor has been solubilized and partially purified by an affinity column chromatography. GABAB receptor was solubilized by 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS) in the presence of asolectin. The solubilized GABAB receptor was adsorbed on baclofen-coupled epoxy-activated Sepharose 6B. The affinity matrix adsorbed 80% of the solubilized [3H]GABA binding activity to GABAB receptor, and approximately 75% of the adsorbed activity could be eluted with 1 M KC1. GABAB receptor binding in the fraction eluted from affinity column was displaced by GABA, baclofen and 2-hydroxy saclofen in a dose-dependent manner. Furthermore, the purified GABAB receptor showed approximately 2800-fold purification as compared with the original solubilized fraction and possessed the specific binding activity of 17.68 p mol/mg of protein. This binding consisted of a single binding site with a dissociation constant of 64.4 nM. The present results indicate that affinity column chromatographic procedures using baclofen-coupled epoxy-activated Sepharose 6B are suitable for the partial purification of GABAB receptor from cerebral tissues.  相似文献   

19.
A rapid and simple method was developed, using perfusion chromatography media, to separate the fruit-specific pectin methylesterase (PME) isoform from the depolymerizing enzyme polygalacturonase (PG) and other contaminating pectinases present in a commercial tomato enzyme preparation. Pectinase activities were adsorbed onto a Poros HS (a strong cation exchanger) column in 20 M HEPES buffer at pH 7.5. The fruit-specific PME was eluted from the column with 80 mM NaCl, followed by a step to 300 mM NaCl to elute PG activity. Rechromatography of the PME activity peak with a linear gradient further resolved two PME isoenzymes and removed residual traces of PG activity. The PG activity peak was further treated with lectin affinity chromatography to provide purified PG enzyme, which was separated from a salt-dependent PME (tentatively identified as a "ubiquitous-type" isoform), and a pectin acetylesterase. The later enzyme has not been reported previously in tomato. This method provides monocomponent enzymes that will be useful for studying enzyme mechanisms and for modifying pectin structure and functional properties.  相似文献   

20.
The neurotensin receptor was purified from newborn mouse brain by affinity chromatography. Active neurotensin binding sites were solubilized from brain homogenates using the nondenaturing detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic acid (CHAPS) in the presence of cholesteryl hemisuccinate. Chromatography of the soluble extract on SP-Sephadex C-25 and hydroxylapatite eliminated 50% of proteins without loss of neurotensin binding activity. This prepurified material was loaded into an affinity column prepared by coupling neurotensin (2-13) to glutaraldehyde-activated Ultrogel AcA22. Nonspecifically adsorbed proteins were eliminated by extensive washing, and the receptor was eluted with a buffer containing 1 M NaCl, 0.1% CHAPS, and 0.02% cholesteryl hemisuccinate. After desalting, the purified receptor bound 125I-labeled neurotensin with a dissociation constant of 0.26 nM and retained its specificity towards a series of neurotensin analogues. The desalted NaCl eluate appeared on sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a major band of molecular weight 100,000 which was identified as the receptor by affinity labeling with 125I-labeled neurotensin in the presence of disuccinimidyl suberate. The purity of the mouse brain receptor eluted from the affinity column was estimated to be 78%. Electroelution of the 100-kDa protein band gave an homogenous preparation of receptor. Very similar results were obtained with CHAPS-solubilized neurotensin receptors from rat and rabbit brain.  相似文献   

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