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1.
Soybean gamma-conglycinin was isolated by isoelectric precipitation and ammonium sulphate fractionation. The crude protein was purified by ion-exchange chromatography on DEAE-Sepharose CL-6B and gel filtration on Sepharose CL-6B. The purified gamma-conglycinin was homogeneous on two kinds of gel electrophoresis and an ultracentrifugal analysis. A subunit band, distinguishable from other subunit bands of beta-conglycinin and glycinin, was detected by sodium dodecyl sulphate electrophoresis. Amino acid composition was similar to those of the other storage proteins of soybean. Some physical properties were also studied.  相似文献   

2.
Arylsulphatases A and B (EC 3.1.6.1) of rabbit kidney cortex were purified 5250- and 7720-fold respectively by a multiple-column-chromatography method. The specific activity toward 4-nitrocatechol sulphate was 42mumol/min per mg for arylsulphatase A and 62 mumol/min per mg for arylsulphatase B. Each enzyme migrated as a single band on polyacrylamide-gel electrophoresis, and the enzyme activity corresponded to the band of protein on the gel. The rate of hydrolysis of ascorbic acid 2-sulphate by arylsulphatase A was three times that for cerebroside 3-sulphate. Arylsulphatase B hydrolysed UDP-N--acetylgalactosamine 4-sulphate and glucosamine 4,6-disulphate, but not galactosamine 6-sulphate.  相似文献   

3.
A procedure is described for the use of immunoadsorption chromatography of hydroxyindole O-methyltransferase (HIOMT). HIOMT was purified from bovine pineal extract by affinity chromatography on immunoglobulins (Ig)-Sepharose. The overall purification was about 45-fold; the yield was 84%. This enzyme constitutes about 2.0% of the soluble proteins in the pineal gland. The enzyme represented a single precipitin line on Ouchterlony double diffusion plate and immunoelectrophoresis. Ultracentrifugation analysis indicated the existence of molecular aggregates of enzyme and disc gel electrophoresis showed one main protein band and several minor bands. However sodium dodecyl sulphate (SDS) gel electrophoresis showed a single protein band with subunit molecular weight 38,000 demonstrating bovine pineal HIOMT to be polymer enzyme of a single subunit. The properties of the purified enzyme including disc gel electrophoretic pattern, the effect of pH, chemicals and substrates and immunological properties were identical with those of the crude enzyme.  相似文献   

4.
The recently discovered heat-stable inhibitor protein of the Ca2+-activated cyclic nucleotide phosphodiesterase (Sharma, R. K., Wirch, E. & Warg, J. H. (1978) J. Biol. Chem., in press) has been purified 238 214-fold from bovine brain extract using an affinity column of the modulator protein--Sepharose 4B conjugate. The purified sample appears to be homogeneous as judged by sodium dodecyl sulphate (SDS) gel electrophoresis. The protein band has a mobility corresponding to that of a polypeptide of molecular weight 68 000. Since the heat-stable inhibitor protein has a molecular weight of 70 000 under nondenaturing conditions, it suggests that it is a monomeric protein. The protein has no inhibitory activity toward the cAMP-dependent protein kinase or protein phosphatase. The purified sample has been tested for various enzyme activities which include ATPase, GTPase, cAMP phosphodiesterase, cGMP phosphodiesterase, 5'-nucleotidase, and protein kinase. None of these activities are exhibited by the purified sample.  相似文献   

5.
Rabbit testis arylsulphatase A was purified 140-fold with a recovery of 20% from detergent extracts of an acetone-dried powder by using DE-52 cellulose column chromatography, gel filtration on Sephadex G-200 and preparative isoelectric focusing. The purified enzyme showed one major band with one minor contaminant on electrophoresis in a 7.5% (w/v) polyacrylamide gel at pH8.3. On sodiumdodecyl sulphate/polyacrylamidegel electrophoresis, a single major band was observed with minor contaminants. The final preparation of enzyme was free from general proteolytic, esterase, hyaluronidase, beta-glucuronidase and beta-galactosidase activities. Rabbit testicular arylsulphatase A exists as a dimer of mol.wt. 110000 at pH7.1. At pH5.0 the enzyme is a tetramer of mol.wt. 220000. Arylsulphatase A appears to consist of two identical subunits of mol.wt. 55000 each. The highly purified enzyme has pI4.6. The enzyme hydrolyses p-nitrocatechol sulphate with Km and Vmax, of 4.1 mM and 80nmol/min respectively, but has no activity toward p-nitrophenyl sulphate. The pH optimum of the enzyme varies with the incubation time. By applying Sephacex G-200 chromatography and preparative isoelectric focusing, one form of enzyme was obtained. The enzyme has properites common to arylsulphatase A of other sources with respect to the anomalous time-activity relationship, pI, inhibition by PO42-, SO32- and Ag+ ions and substrate affinity to p-nitrocatechol sulphate. However, the enzyme shows the temperature optimum of arylsulphatase B of other species.  相似文献   

6.
Purification and characterization of an extracellular invertase produced by Aspergillus ochraceus TS are reported. The enzyme was purified (42-fold) from culture filtrate by salt precipitation, ion-exchange and gel filtration. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) of the purified enzyme showed a single band of molecular mass 66 kDa. The molecular mass of the native enzyme was found to be 130 kDa by gel filtration. The purity of the protein was also checked against its antiserum raised in rabbits by two-dimensional immunodiffusion in agarose gel and Western blot that showed a single band. It is a glycoprotein with mannose as its carbohydrate residue. The enzyme showed high affinity for sucrose with a Km of 3.5 mM. The amino acid analysis revealed a high proportion of acidic residues but it had a low content of cysteine, histidine and arginine comparable to other fungal invertases.  相似文献   

7.
A chitinase (EC. 3.2.1.14) from autolysed culture filtrate of Penicillium oxalicum was purified by precipitation with ammonium sulphate, gel filtration and ion exchange chromatographies. The purified enzyme showed a single protein band in SDS gel electrophoresis. The enzyme is an acidic protein with a pI of 4.5 and has a molecular weight of 54 900 as estimated from SDS gel electrophoresis and 21 500 from gel filtration. The optimum pH and temperature were 5.0 and 35°C, respectively. The enzyme was stable at temperatures up to 45°C and in a pH range between 4.0 and 6.0. The Km was 2.5 mg ml-1 for colloidal chitin, Hg2+ and Ag+ were effective inhibitors. The viscosimetric study carried out using carboxymethyl chitin as substrate revealed the endotype action of this enzyme.  相似文献   

8.
CSF-1 was isolated from a large volume of human normal urine (10,000 l), using the following 5 stages of purification: concentration by dialysis, silica gel adsorption, hydrophobic chromatography on phenyl-Sepharose CL-6B, fast protein liquid chromatography (FPLC) and finally preparative electrophoresis on polyacrylamide gels. We have isolated 8 mg of purified CSF-1 which migrated as a single band under non-reducing conditions in SDS-PAGE (staining with Coomassie Blue and the sensitive silver techniques). But in the presence of dithiothreitol, the SDS-PAGE pattern revealed a minor second band with a molecular mass of 50,000 Da. CSF-1 was purified 100,000-fold and has a specific activity of 2.16 X 10(7) units/mg protein. Its apparent molecular mass is 57,000 Da with an isoelectric point, pI = 5.8-6.0. The amino-acid composition is reported and compared with that of murine CSF-1. The carbohydrate content (sialic acid, sulphate groups, N-acetylglucosamine, N-acetylgalactosamine) was also determined, and it shows that CSF is a glycoprotein.  相似文献   

9.
Hyaluronic acid binding protein (HBP) has been purified to homogeneity from normal rat brain by using Hyaluronate-Sepharose affinity chromatography. It appears as a single band in non-dissociating gel electrophoresis. The molecular weight of native protein, as determined by gel filtration is found to be 68,000 daltons, and has a single subunit of molecular weight approximately 13,500 as determined under denaturing conditions in polyacrylamide gel electrophoresis, indicating that this protein is apparently composed of five identical subunits. Amino acid analysis shows the purified HBP to be rich in glycine and glutamic acid content, and is distinct from fibronectin, link proteins, and gelatin binding proteins which are known to bind to hyaluronic acid. This protein is further characterised as sialic acid containing glycoprotein.  相似文献   

10.
Incubation of purified cyclic guanosine 3':5'-monophospate-dependent protein kinase with [gamma-32P]ATP and Mg2+ led to formation of one 32P-labeled protein, Mr = 75,000, which corresponded to the single protein band detected after polyacrylamide gel electrophoresis in sodium dodecyl sulfate. When electrophoresis was performed without detergent, the labeled protein coincided with the position of cGMP-dependent protein kinase activity. Phosphorylation was enhanced severalfold by either histone or cAMP and was inhibited by the addition of cGMP. Low concentrations of cGMP blocked the stimulatory effects of cAMP or histone (or both). Since neither cAMP-dependent protein kinase nor cGMP-dependent phosphoprotein phosphatase activities were detected in the purified enzyme, we concluded that the cGMP-dependent protein kinase is a substrate for its own phosphotransferase activity and that other protein substrates (histone) and cyclic nucleotides modulate the process of self-phosphorylation.  相似文献   

11.
Abstract A cell-associated hemagglutinin (HA) was isolated and purified from a clinical isolate of Shigella dysenteriae type 1 by affinity chromatography on a fetuin-agarose column. The purified hemagglutinin produced a single-stained protein band of around 66 kDa in sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). In an immunodiffusion test, HA-antisera produced a single precipitin band against the purified HA without exhibiting any reactivity towards lipopolysaccharide (LPS) of S. dysenteriae type 1 strain. Inhibition of the hemagglutination by the glycoproteins fetuin, asialofetuin and a sugar derivative N -acetyl-neuraminic acid but not by simple sugars, suggested the specific requirement of complex carbohydrate for binding. Electron micrographs of the purified HA revealed a morphology typical of globular protein.  相似文献   

12.
A glycolipid-specific lipid transfer protein has been purified to apparent homogeneity from pig brain post-mitochondrial supernatant. The purified protein was obtained after about 6,000-fold purification at a yield of 19%. Evidence for the homogeneity of the purified protein includes the following: (i) a single band in acidic gel electrophoresis, in sodium dodecyl sulfate-gel electrophoresis, (ii) a single band in analytical gel isoelectric focusing, (iii) exact correspondence between the glycolipid transfer activity and stained protein absorbance in the acidic gel electrophoresis, and (iv) coincidence between the transfer activity and protein absorption at 280 nm in gel filtration through Ultrogel AcA 54. The protein has an isoelectric point of about 8.3 and a molecular weight of 22,000, as measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A molecular weight of 15,000 was calculated from AcA 54 gel filtration. The amino acid composition has been determined. The protein binds [3H]galactosylceramide but not [3H]phosphatidylcholine. Under the conditions used, 1 mol of the transfer protein bound about 0.13 mol of [3H]galactosylceramide. The glycolipid transfer protein-[3H]galactosylceramide complex was isolated by a Sephadex G-75 chromatography. An incubation of the complex with liposomes resulted in the transfer of [3H]galactosylceramide from the complex to the acceptor liposomes. The result indicates that the complex functions as an intermediate in the glycolipid transfer reaction. The protein facilitates the transfer of [3H]galactosylceramide from donor liposomes to acceptor liposomes lacking in glycolipid as well as to acceptor liposomes containing galactosylceramide.  相似文献   

13.
N5-(L-1-Carboxyethyl)-L-ornithine:NADP+ oxidoreductase (EC 1.5.1.-) from Streptococcus lactis K1 has been purified 8,000-fold to homogeneity. The NADPH-dependent enzyme mediates the reductive condensation between pyruvic acid and the delta- or epsilon-amino groups of L-ornithine and L-lysine to form N5-(L-1-carboxyethyl)-L-ornithine and N6-(L-1-carboxyethyl)-L-lysine, respectively. The five-step purification procedure involves ion-exchange (DE52 and phosphocellulose P-11), gel filtration (Ultrogel AcA 44), and affinity chromatography (2',5'-ADP-Sepharose 4B). Approximately 100-200 micrograms of purified enzyme of specific activity 40 units/mg were obtained from 60 g of cells, wet weight. Anionic polyacrylamide gel electrophoresis revealed a single enzymatically active protein band, whereas three species (pI 4.8-5.1) were detected by analytical electrofocusing. The purified enzyme is active over a broad pH range of 6.5-9.0 and is stable to heating at 50 degrees C for 10 min. Substrate Km values were determined to be: NADPH, 6.6 microM; pyruvate, 150 microM; ornithine, 3.3 mM; and lysine, 18.2 mM. The oxidoreductase has a relative molecular mass (Mr = 150,000) as estimated by high pressure liquid chromatography exclusion chromatography and by polyacrylamide gradient gel electrophoresis. Conventional gel filtration indicated an Mr = 78,000, and a single protein band of Mr = 38,000 was revealed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme is composed of identical subunits of Mr = 38,000, which may associate to yield both dimeric and tetrameric forms. Polyclonal antibody to the purified protein inhibited enzyme activity. The amino acid composition of the enzyme is reported, and the sequence of the first 37 amino acids from the NH2 terminus has been determined by stepwise Edman degradation.  相似文献   

14.
Purification of larvicidal protein from Bacillus sphaericus 1593   总被引:4,自引:0,他引:4  
Coat proteins from the spores of Bacillus sphaericus 1593 were separated by preparative polyacrylamide gel electrophoresis. Neutralising antibodies were raised against a single protein band exhibiting toxicity to mosquito larvae. IgG was purified and coupled to CNBr-activated Sepharose 4B to be used as an immunoaffinity matrix. The larvicidal protein was purified to electrophoretic homogeneity using this immunoaffinity column. The single protein species resolved into four peptides of molecular weights 42.6, 44.1, 50.7 and 51.3 KDa on polyacrylamide gel electrophoresis under denaturing conditions. This protein contained 12% carbohydrates. The purified protein exhibited an LC50 value of 8.3 +/- 1.6 ng/ml when tested against early third instar larvae of the mosquito Culex pipiens var quinquefasciatus.  相似文献   

15.
Two anion-transporting systems, i.e., the dicarboxylate carrier and the 2-oxoglutarate carrier, have been purified from rat liver mitochondria and functionally identified. The dicarboxylate carrier has been isolated in active form by hydroxyapatite chromatography after partial removal of the solubilizing detergent Triton X-114 from the mitochondrial extract. The SDS gel electrophoresis of this preparation consists mainly of one protein band with an apparent Mr of 28,000, identified as the dicarboxylate carrier. Complete purification of the 28 kDa protein in inactive form has been achieved by sequential chromatography on hydroxyapatite and Celite followed by SDS extraction of the retained protein. The 2-oxoglutarate carrier has been purified by hydroxyapatite chromatography after extensive removal of Triton X-114 from the detergent extract. SDS gel electrophoresis of the purified fraction shows a single band with an apparent Mr of 32,500. When reconstituted into liposomes, the functional properties of the two isolated carrier proteins resemble closely those of the dicarboxylate and the 2-oxoglutarate transport systems characterized in mitochondria.  相似文献   

16.
1. The polypeptide composition of purified QH2: cytochrome c oxidoreductase prepared by three different methods from beef-heart mitochondria has been determined. Polyacrylamide gel electrophoresis in the presence of dodecyl sulphate resolves eight intrinsic polypeptide bands; when, in addition, 8 M urea is present and a more highly cross-linked gel is used, the smallest polypeptide band is resolved into three different bands. 2. The identity of several polypeptide bands has been established by fractionation. The two heaviest polypeptides (bands 1 and 2) represent the so-called core proteins, band 3 the hemoprotein of cytochrome b, band 4 the hemoprotein of cytochrome c1, band 5 and Rieske Fe-S protein, band 6 a polypeptide associated with cytochrome c1 and identified with the so-called oxidation factor, and band 7 a polypeptide peptide associated with cytochrome b. 3. The validity of molecular weight estimate for the polypeptides of the enzyme based on their mobility on dodecyl sulphate gels has been examined. The polypeptides of bands 1, 2 and 3 showed anomalous migration rates. The molecular weights of the other polypeptides have been estimated from their relative mobilities on either dodecyl sulphate gels or 8 M urea-dodecyl sulphate gels as 29 000, 24 000, 12 000, 8000, 6000, 5000 and 4000, respectively. 4. The stoicheiometry of the different polypeptides in the intact complex was determined using separate staining factors for the individual polypeptide band.  相似文献   

17.
The product of the incorporation of [14C]tyrosine as single unit into a protein of the soluble fraction of rat brain homogenate was purified by following a procedure used to purify tubulin. Sodium dodecylsulphate-polyacrylamide gel electrophoresis of the purified material showed a single protein band containing all the radioactivity. Purification data indicate that this protein accounts for 10.2% of the total protein of the supernatant fraction. This is in good agreement with the amount found for tubulin by the [3H]colchicine-binding method (10.5% of the total protein). The incorporated [14C]-tyrosine was found in the alpha-subunit of tubulin. Protein labelled with [3H]colchicine and [14C]tyrosine was precipatated with vinblastine sulphate and the radioactivity of 3H and that of 14C were quantitatively recovered in the precipitate (98%). Sodium dodecylsulphate-polyacrylamide gel electrophoresis of the vinblastine precipitate showed that the 14C radioactivity moved with the tubulin band. Results obtained in experiments with phenylalanine and 3,4-dihydroxyphenylalanine were identical to those obtained for tyrosine. Bineing of colchicine did not interfere with the incorporation of tyrosine. About 30% of tubulin from rat brain supernatant fraction can incorporate tyrosine as single unit.  相似文献   

18.
Brush border membrane trehalase was purified from monkey small intestine by a procedure which includes solubilisation by Triton X-100, ammonium sulphate fractionation, and chromatography on DE-52 and hydroxyapatite. The purified enzyme had a specific activity of 11 units/mg protein and was purified 140-fold. The enzyme showed a single protein band on Polyacrylamide gel electrophoresis. It had aK m value of 17.4 mM for trehalose and a Vmax of 1.33 units. Sucrose and Tris acted as competitive inhibitors of the enzyme.  相似文献   

19.
郭慧  R.  N.  库利 《菌物学报》1990,9(4)
本文报道了利用具有潮霉素抗性标记的质粒(pAN7-1)对粟长蠕孢菌原生质体进行转化的结果。经pAN7-1质粒DNA转化处理的粟长蠕孢菌原生质体在含潮霉素(200μg/ml)的选择性培养基上出现两类转化子。一类是正常转化子,其转化率为2个转化子/μg DNA;另一类是流产转化子,其产生频率为500—600个转化子/μg DNA。DNA杂交分析结果表明,在正常转化子中质粒DNA以首尾相接、重复排列的形式整合入受体菌染色体DNA。初筛获得的转化子多数以异核状态存在,经单孢分离纯化后可通过有丝分裂稳定传代。  相似文献   

20.
Hyaluronic acid binding protein (HBP) was purified homogeneously from normal adult rat liver by hyaluronate-sepharose affinity chromatography. The molecular weight of this protein as determined by gel filtration was found to be 64,000 daltons. This protein HBP appeared as a single band in non-dissociating gel electrophoresis and has a subunit of molecular weight approximately 12,000 as determined by SDS-gel electrophoresis.  相似文献   

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