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1.
An acidic heteropolysaccharide preparation derived from the mycelium of Fusarium sp. M7-1 was fractionated into two fractions, precipitable and nonprecipitable, by treatment with cetyltrimethylammonium bromide (Cetavlon). These two fractions were further purified to apparent homogeneity on ultracentrifugation by treatment with charcoal and gel filtration chromatographies. Two glycoproteins, precipitable GP I and nonprecipitable GP II, were obtained. The molecular weights of GP I and GP II were estimated to be about 8.8 x 10(4) and 3.7 x 10(4), respectively, on gel filtration chromatography. Both GP I and GP II contained a high proportion of serine and threonine. Treatment of GP I and GP II with alkaline solution resulted in an increase in absorbance at 240 nm. Alkaline borohydride treatment markedly decreased the number of seryl and threonyl residues and resulted in an increase in alanine and the formation of 2-aminobutyric acid. It also resulted in release of low and high molecular weight carbohydrate chains. From these results, we conclude that both GP I and GP II are glycoproteins with carbohydrate chains attached to the protein moiety through O-glycosidic linkages to the hydroxyl group of serine and/or threonine.  相似文献   

2.
Lipoprotein-lipase extracted from rat adipose tissue acetone-ether powders, was separated by gel filtration on Biogel A 1.5 M into two active fractions: lipoprotein-lipase “a” and lipoprotein-lipase “b” as named by Garfinkel et al. (1). Then each of these two fractions was again chromatographed on heparin-Sepharose column according to our own method (2). The lipoprotein-lipase “b” was eluted in the first fraction like the microsomal lipoprotein-lipase; lipoprotein-lipase “a” was eluted in the second one like plasma membranes lipoprotein-lipase (3). We compared the properties of the two lipoprotein-lipases obtained by those two different chromatographic methods.  相似文献   

3.
In commercial digested and purified horse diphtheria antitoxin, which is formed largely of the gamma globulin fragment with the sedimentation coefficient 5.3 S, the reactive disulphide bonds were destroyed by S-sulphonation. Gel filtration on Sephadex G-100 in 0.05 M formic acid with 6 M urea showed that the molecule of the S-sulphonated preparation dissociated into chains similar in character to the peptide chains of native horse antitoxins. Antibody activity was still partly maintained even after treatment with 6 M urea. On mixing the two types of chains isolated by gel filtration, antibody activity was recovered, the amount of antibody protein determined in the mixed fractions being greater than the sum of the amounts in the separate fractions. The neutralizing activity of the mixed fractions tested against toxinin vivo was also greater than the sum of the activity of the separate fractions.  相似文献   

4.
RNase T2 bound to an affinity adsorbent, 5'-adenylate-aminohexyl-Sepharose 4B, specifically at pH 4.5. The colorless enzyme was eluted only by the simultaneous addition of 2'(3')-AMP (1 mM) and NaCl (greater than 1 M) at pH 4.5. By applying this affinity chromatography to the purification of RNase T2, pure enzyme with a specific activity of 60 was obtained in only four steps and the yield was about 10 times higher than that of the previous purification method. This enzyme preparation was found to be heterogeneous in molecular weight and was separated into two fractions on Sephadex G-75 gel filtration. As the smaller enzyme with a molecular weight of 36,000 was identical with RNase T2 in every property examined, we tentatively designated the larger one with an apparent molecular weight of 80,000 as high molecular weight RNase T2 (RNase T2-L). RNase T2-L was still heterogeneous and was separated into five fractions, RNases T2-L 1-5, by repeated Sephadex G-150 gel filtration. The amino acid and carbohydrate analyses revealed that each of these fractions has a protein moiety in common with RNase T2 and the heterogeneities were due to the carbohydrate content, mainly galactose content.  相似文献   

5.
The heterogeneity and chemical composition were investigated in κ-casein from colostrum. The acid casein was obtained from four different Holstein cow colostra. The yield of acid casein from colostrum was higher than that from normal milk. κ-Casein from colostrum was prepared by the gel filtration method of Yaguchi et al. The gel filtration profiles differed among the four colostrum acid caseins.

Colostrum κ-casein was fractionated on a DEAE-cellulose column into one nonadsorbed and six adsorbed fractions with increasing salt concentration. Six adsorbed fractions had the same molecular weight and stabilizing ability for αs1-casein in the presence of calcium ion. The amino acid composition and the phosphorus content of the adsorbed fractions were identical, but fractions eluted with high salt concentrations had more carbohydrates (galactose, sialic acid, glucosamine, galactosamine). Colostrum κ-casein was characterized by a higher content of carbohydrate moiety in comparison with normal κ-casein. Also glucosamine which has not been found in normal κ-casein was detected in colostrum κ-casein. The κ-casein component from colostrum contained at least one molecule of carbohydrate, though the carbo hydrate-free component was detected in normal κ-casein.  相似文献   

6.
We have isolated a “soluble” fraction of Streptomyces albus G membranes or membranes previously solubilised by sodium dodecylsulphate, using n-butanol extraction. Polyacrylamide gel electrophoresis in sodium dodecylsulphate of the whole membrane showed a complex protein pattern (about 20–25 bands) with two predominant groups. The “soluble” fraction represented about 25% of the membrane protein and contained part of the major polypeptides. The yield of protein in “soluble” form decreased when membranes were suspended in water and di not significantly change if membranes were reduced with sodium dithionite and then treated with iodoacetamide. A change in relative mobility of some of these polypeptides seemed to occur with membrane delipidation. The proteins of the fraction appear to be glycoproteins as indicated by their simultaneous staining for protein and carbohydrate and the parallel sensitivity to trypsin of both stains. The apparent molecular weights by sodium dodecylsulphate gel electrophoresis of the proteins (glycoproteins) were: 63 000, 40 000 and 17 000. Similar protein patterns were obtained by extraction of the membranes with EDTA and non-ionic detergents. Lipid and nucleotide material were also found in the “soluble” fraction.The “soluble” fraction showed by gel filtration on Sephadex G-200 the existence of different states of aggregation. These states of aggregation revealed the same electrophoretic pattern of proteins, which seemingly corresponded to that of the original fraction (i.e. three protein groups with relative mobilities 0.65, 0.80 and 1.0). Treatment of the samples under different conditions with 1% dodecylsulphate (supplemented or not with 0.5% β-mercaptoethanol) failed to completely dissociate the fraction as shown by Sephadex filtration.  相似文献   

7.
Cell envelope glycoproteins were extracted with sodium dodecyl sulfate from isolated cell walls of two strains of Serratia marcescens and purified by gel filtration column chromatography on Sepharose 4B. There was no significant difference in the chemical composition. Both fractions contained approximately 50% proteins and 10% carbohydrates. Glucosamine and glucose were identified as the only sugar components in the carbohydrate moiety. Immunochemically they shared at least one common antigenic component with each other and possibly with their corresponding lipopolysaccharide fractions.  相似文献   

8.
Using immobilized monoclonal antibodies, a tissue-specific antigen, chordin, was isolated from cell extracts of giant sturgeon (beluga) notochord. The antigen was further purified by gel filtration through SP-Sephadex (pH 2.1) and gel chromatography on TSK Toyopearl HW-60. Purified chordin preparations contained 40% of protein and 60% of carbohydrates. The predominant polar amino acids were threonine, serine, glycine, asparagine and glutamine (or aspartic and glutamic amino acids). The carbohydrate moiety comprised mannose, fucose, galactose, galactosamine and glucosamine. Treatment of chordin with three enroglycosidases specifically hydrolyzing the carbohydrate chains of proteoglycans did not affect the antigenic properties of chordin or its behaviour on gel filtration. These findings and the fact that 75% of galactosamine was converted to galactosaminite after treatment with alkaline NaBH4 permitted to relate chordin to glycoproteins carrying O-glycosidic carbohydrate-peptide bonds between the N-acetyl-galactosamine and beta-hydroxyamino acid residues. Besides, chordin seems to contain a N-glycosylamide carbohydrate-peptide bond as can be judged from glucosaminite formation after treatment of the antigen with alkaline LiHB4. The changes in the antigenic properties of chordin after its treatment with neuraminidase, pronase, sodium periodate, alkali, alkaline NaBH4 or LiBH4 suggest that the polypeptide moiety of the chordin molecule and, perhaps, the N-acetylgalactosamine within the composition of the carbohydrate-peptide bond are involved in the construction of its most immunogenic determinants (P-determinants).  相似文献   

9.
The chemical constitution of the carbohydrate portion of mycodextranase, an exocellular endo-alpha(1 yields 4) D-glucanase of Penicillium melinii, has been investigated. At least 80% of the carbohydrate, consisting exclusively of mannose and glucose, is released from protein by treatment of the enzyme with 0.05 M potassium hydroxide plus 1 M sodium borohydride or 0.5 M sodium hydroxide at 50 degrees. There is concomitant destruction of 60% of the threonine and 15% of the serine of the treated enzyme and an increase in absorption, at 241 nm, of the treated protein's spectrum, indicative of an O-glycosidic beta-hydroxyamino acyl linkage between untreated protein and its associated carbohydrate. Mannose is the monosaccharide involved in this linkage. Smith degradation, methylation, and glycosidase digestions of the carbohydrate indicate that it is present in mycodextranase as side chains of mannose, glucosyl alpha(1 yields 2)-mannose, and mannosyl alpha(1 yields 2)-glucosyl alpha(1 yields 2)-mannose units with each enzyme molecule bearing a calculated average of 25 side chains. Separation of pronase glycopeptides by gel filtration on Sephadex G-25 revealed that 96% of the carbohydrate is present in the highest molecular weight fraction which contains 60% of the threonine of mycodextranase but only 3.5% of the aromatic acids judged by its absorbance at 280 nm. Further fractionation of this glycopeptide component on Sephadex G-75 indicates carbohydrate is restricted to two fractions, one containing 71% by weight of the threonine and serine of mycodextranase and 56% of its carbohydrate. These results suggest carbohydrate chains of mycodextranase are clustered in a few threonin-rich regions along the polypeptide chain rather than being separated from each other by nonglycosylated areas.  相似文献   

10.
Two carbohydrate rich fractions A and B were isolated from wheat gluten. Fraction B contained more lipid than fraction A. Lipid portion of fraction B consisted mainly of glycolipid and was fractionated into five fractions by thin-layer chromatography. The two main fractions were extracted and determined to be galactolipid and glucolipid, respectively, by the analyses of fatty acid and sugar components by gas chromatography. Defatted fraction A was assumed to consist of glycoprotein. After complete pronase digestion of defatted fraction A, the remaining glycopeptide moiety was isolated by column chromatography on DEAE-cellulose followed by gel filtration through Sephadex G–25. The amino acid and sugar components of the glycopeptide were investigated.  相似文献   

11.
Purified Japanese monkey pepsinogens I and II contain carbohydrate as a part of the enzyme molecule. By gel filtration on Sephadex G-100, chromatography on DE-32 cellulose, and polyacrylamide disc gel electrophoresis, the carbohydrate moiety could not be separated from the enzyme protein, and the content did not decrease on repeated chromatography. Glycopeptides were obtained by successive digestion of pepsinogens with thermolysin and aminopeptidases and isolated by chromatography on Sephadex G-25 and G-50. Identification and determination of carbohydrate components was performed by paper and gas-liquid chromatographies. The presence of 4 glucosamines, 6 galactoses, 6--8 mannoses, and 8--11 fucoses per molecule of the glycopeptide of both pepsinogens was observed, of which the high content of fucose is especially unique. The molecular weight of the carbohydrate chains should be around 4,000--5,000. The amino acid sequence of a major glycopeptide was deduced to be Ile-Gly-Ile-Gly-Thr-Pro-Gln-Ala-Asn, in which the asparagine residue is the site of attachment of the carbohydrate chain.  相似文献   

12.
A chondroitin sulfate-dermatan sulfate proteoglycan was isolated from bovine aorta intima by extraction of the tissue by 4 M guanidine hydrochloride. The proteoglycan was purified by CsCl isopycnic centrifugation followed by gel filtration and ion-exchange chromatography. The proteoglycan had 21.9% protein, 22.1% uronate, 21.4% hexosamine and 10.8% sulfate. Glycosaminoglycan chains obtained from the proteoglycan by beta-elimination were resolved by gel filtration into two fractions, one containing chondroitin 6-sulfate with an approximate molecular weight of 49 000 and the other containing chondroitin 4-sulfate and dermatan sulfate in a proportion of 2:1 with an approximate molecular weight of 37 000. Digestion of the proteoglycan by chondroitinase ABC or AC yielded a protein core with similar composition and behavior in gel filtration and SDS-polyacrylamide gel electrophoresis. An approximate molecular weight of 180 000 was estimated for the core protein. Dermatan sulfate chains with an approximate molecular weight of 10 000 were observed only in the digest of chondroitinase AC. Limited trypsin hydrolysis of the proteoglycan yielded three peptide fragments containing chondroitin 6-sulfate, chondroitin 4-sulfate and dermatan sulfate in varied proportions. A tentative structure for the proteoglycan was suggested.  相似文献   

13.
A chondroitin sulfate - dermatan sulfate proteoglycan was isolated from bovine aorta intima by extraction of the tissue by 4 M guanidine hydrochloride. The proteoglycan was purified by CsCl isopycnic centrifugation followed by gel filtration and ion-exchange chromatography. The proteoglycan had 21.9% protein, 22.1% uronate, 21.4% hexosamine and 10.8% sulfate. Glycosaminoglycan chains obtained from the proteoglycan by β-elimination were resolved by gel filtration into two fractions, one containing chondroitin 6-sulfate with an approximate molecular weight of 49 000 and the other containing chondroitin 4-sulfate and dermatan sulfate in a proportion of 2:1 with an approximate molecular weight of 37 000. Digestion of the proteoglycan by chondroitinase ABC or AC yielded a protein core with similar composition and behavior in gel filtration and SDS-polyacrylamide gel electrophoresis. An approximate molecular weight of 180 000 was estimated for the core protein. Dermatan sulfate chains with an approximate molecular weight of 10 000 were observed only in the digest of chondroitinase AC. Limited trypsin hydrolysis of the proteoglycan yielded three peptide fragments containing chondroitin 6-sulfate, chondroitin 4-sulfate and dermatan sulfate in varied proportions. A tentative structure for the proteoglycan was suggested.  相似文献   

14.
Pituitary homogenates and plasma from untreated and estrogen treated ovariectomized rats were subjected to gel filtration chromatography and the prolactin in fractions collected between the void and total elution volumes of the columns was determined by radio- immunoassay. Three components of prolactin, identified as “void volume”, “big” and “little” according to increasing elution volumes, were observed in pituitary homogenates of ovariectomized rats. These three components accounted for 4, 11 and 85% of the total prolactin activity respectively. Estrogen treatment of ovariectomized rats increased the total prolactin in the pituitary and also selectively increased the “big” component to 21% of the prolactin activity on the column. A smaller increase was also observed in the “void volume” component. Gel filtration of the plasma obtained from estrogen-treated rats before and during the estrogen-induced afternoon surge of prolactin showed that “little” prolactin was the predominate form being secreted and that the “void volume” and “big” components were also released. The release of the components was not in proportion to that observed in the pituitary and the larger components were released in a nonuniform manner. The “void volume” component appeared in the plasma as the surge began but then disappeared as the “big” component appeared at the peak of the surge. The big component decreased as the surge waned leaving primarily “little” component in plasma. The data indicate (1) that estrogen stimulates the formation of the larger components of prolactin in the pituitary (2) that the types of prolactin released into plasma of estrogen-treated ovariectomized rats is not in proportion to that found in the pituitary and (3) that the heterogeneous forms of prolactin are selectively released into plasma during the prolonged secretory episode of the afternoon surge of prolactin induced by estrogen.  相似文献   

15.
Buffer-soluble and pronase-liberated glycoproteins from experimental granulation tissue were fractionated by gel filtration and DEAE-cellulose chromatography. The age of the granuloma was reflected in the gel filtration pattern. Two glycoproteins were isolated, purified to homogeneity and analyzed for their carbohydrate and amino acid compositions.The collagen synthesis in embryonic chick tendon cells was measured in the presence of these fractions, which were found to be inhibiting even at 10?6 M. These glycoproteins may be significant in the feedback regulation of the development of granulation tissue and fibrosis.  相似文献   

16.
Protein and carbohydrate moieties of a preparation of β-lactamase II   总被引:3,自引:3,他引:0  
1. A crystalline preparation of beta-lactamase II has been separated into two moieties by gel filtration on a column of Sephadex G-100. 2. The first moiety consisted mainly of carbohydrate and showed virtually no beta-lactamase activity. 3. The second moiety was a protein of molecular weight 22500, which was enzymically active. 4. The protein moiety, like the original protein-carbohydrate complex, required Zn(2+) for beta-lactamase activity. It did not differ significantly from the complex in its behaviour to a number of cephalosporin substrates, but was less stable to heat than the complex. 5. About 30% of the total beta-lactamase activity was lost when the protein-carbohydrate complex was separated into the two moieties. This activity was regained when the protein and carbohydrate moieties were mixed, but the mixture did not show the heat stability of the original complex.  相似文献   

17.
A heparan sulfate proteoglycan from bovine lung gas-exchange tissue was isolated by extraction of the tissue with 4.0 M guanidine HCl in the presence of multiple protein inhibitors. The proteoglycan was purified by precipitation with cetylpyridinium chloride in 0.5 M KCl followed by CsCl isopycnic centrifugation (po = 1.45) in 4.0 M guanidine/HCl. Further purification was achieved by gel filtration on Sepharose CL-2B and by chromatography in DEAE-Sepharose CL-6B column. The proteoglycan had 14.9% protein and 22.4% uronate. Heparan sulfate chains from the proteoglycan were isolated after beta-elimination. Fractionation of heparan sulfate chains was achieved on Dowex-1 Cl- column, eluting with a stepwise increase in the concentration of NaCl, 1.0 to 2.0 M with 0.2 M increments. Of the total heparan sulfate recovered from the column, about 10% eluted by 1.2 M NaCl, 68% by 1.4 M NaCl, 18% by 1.6 M NaCl and 4% by 1.8 M NaCl. The fractions varied in their total and N-sulfate ester contents and iduronic acid to glucuronic acid ratios. The fraction that eluted from the Dowex-1 Cl- column at 1.6 M NaCl had the highest molecular weight, 37000, and the fraction that eluted at 1.8 M NaCl had the lowest molecular weight, 12000, as determined by gel filtration method, and the greatest sulfate content. The core protein, obtained by digestion of proteoglycan by heparan sulfate lyase, showed mostly a single band in SDS-polyacrylamide gel electrophoresis. The observations indicate a heterogeneity of the composition of heparan sulfate chains in the proteoglycan. This heterogeneity likely contributes to variations in biologic properties of different heparan sulfate proteoglycan preparations.  相似文献   

18.
Demembranated cilia of Tetrahymena pyriformis were extracted with KCl or Tris-EDTA and the crude dyneins from each resolved by sucrose density gradient sedimentation into 14S-K, 30S-K, 14S-E and 30S-E dyneins, respectively. The calmodulin activation ratio (ATPase activity in presence of added calmodulin/ATPase activity in absence of added calmodulin) did not vary across the 30S dynein fractions regardless of the method of extraction nor did it vary across the 14S-E region. However, in going from the “heavy” fractions to the “light” fractions of the 14S-K region, it increased markedly. The concentration of calmodulin required for half-maximal activation did not differ appreciably in the “light” versus the “heavy” fractions of the 14S-K region, suggesting that the affinity for calmodulin does not vary in these fractions. SDS-polyacrylamide gel electrophoresis studies showed the presence of several polypeptides that varied in a systematic fashion across the 14S-K region and hence may be involved in regulating the sensitivity of 14S-K dynein ATPase activity to added calmodulin.  相似文献   

19.
M Ledig  P Mandel 《Biochimie》1978,60(1):25-34
We describe a method of extraction and partial purification of phosphopeptides isolated from pig brain or from the electrical organ of Torpedo marmorata. The extraction of the phosphopeptides was achieved by alcoholic 0,04 N potassium hydroxyde solution or by 10(-1) M KCL containing 10(-3) M EDTA and 10(-4) M DTT. After having tried various fractionation methods like ion exchange chromatography or gel filtration we chose chromatography on DEAE Sephadex followed by purification of the isolated fractions by Sephadex G 25 filtration. The most important phosphate fractions (one was purified to about 90 per cent) were characterized by the determination of the N/P ratio which was different from one phosphopeptide to another. The amino acid composition showed a high glycin, serine and "acid" amino acid content.The presence of phosphoserine was shown by electrophoresis and chromatography of a partial hydrolysate of in vivo 32P labelled phosphopeptides isolated from rat liver. The polyanionic structure of these phosphopeptides allow them to act as real ion exchangers which might be involved during active transport mechanisms in cellular membranes.  相似文献   

20.
Correlated ultrastructural and biochemical methods were used to identify and localize Concanavalin A (Con A) receptors in the desmosomes of bovine epidermis. Specific carbohydrate residues were labeled with ferritin-Con A in thin sections of tissue embedded in a hydrophilic resin. Quantitative mapping of ferritin distribution in labeled desmosomes revealed that Con A receptors are localized in the intercellular zone and concentrated along the desmosomal midline or central dense stratum. Labeling was almost entirely absent when sections were treated with ferritin-Con A in the presence of 0.1 M α-methyl mannoside, a hapten-inhibitor of Con A. “Whole” desmosomes and desmosomal intercellular regions (desmosomal “cores”) were purified from bovine muzzle epidermis. Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis reveals a limited number of major desmosomal protein constituents. Certain of these are glycoproteins and are greatly enriched in the core fraction. Almost all the desmosomal glycoproteins are intensely labeled when electrophoretic gels of whole desmosome or core fractions are exposed to fluorescent Concanavalin A.  相似文献   

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