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1.
Two cytolytic toxins (cytolysins Or-A and Or-G) were isolated from the Sea of Japan anemone Oulactis orientalis and characterized. Their purification scheme involved a hydrophobic chromatography on Polychrom 1, a gel filtration on Akrilex P-4, a cation-exchange chromatography on CM-32 cellulose, and a reversed-phase HPLC on a Nucleosil C18 column. The molecular masses of Or-A and Or-G were determined by SDS-PAGE in 14% PAG to be ca. 18 kDa. The absence of Cys residues and a high content of basic amino acid residues are characteristic of their amino acid compositions. The hemolytic activities of Or-A and Or-G were found to be 295.86 and 322.58 HU/mg, respectively; these are by three orders of magnitude lower than those of sphingomyelin-inhibitable cytolysins from the tropic sea anemones. The amino acid sequences of the N-terminal fragments of Or-A and Or-G were determined to be ATFRVLAK and GAIIAGAA, respectively. Action of the cytolysins on the erythrocyte membrane is inhibited by exogenous sphingomyelin. They form ion channels in bilayer lipid membranes with the conductivity of 16, 32, and 40 pSm in 0.1 M NaCl and 168, 240, and 320 pSm in 1 M NaCl at pH 7.2. Therefore, they were attributed to the group of actinoporins.  相似文献   

2.
Two cytolytic toxins (cytolysins Or-A and Or-G) were isolated from the Sea of Japan anemone Oulactis orientalis and characterized. Their purification scheme involved a hydrophobic chromatography on Polychrom-1, a gel filtration on Akrilex P-4, a cation-exchange chromatography on CM-32 cellulose, and a reverse-phase HPLC on a Nucleosil C18 column. The molecular masses of Or-A and Or-G were determined by SDS-PAGE in 14% PAG to be ca. 18 kDa. The absence of Cys residues and a high content of basic amino acid residues are characteristic of their amino acid compositions. The hemolytic activities of Or-A and Or-G were found to be 295.86 and 322.58 HU/mg, respectively; these are by three orders of magnitude lower than those of sphingomyelin-inhibitable cytolysins from the tropic sea anemones. The amino acid sequences of the N-terminal fragments of Or-A and Or-G were determined to be ATFRVLAK and GAIIAGAA, respectively. Action of the cytolysins on the erythrocyte membrane is inhibited by exogenous sphingomyelin. They form ion channels in bilayer lipid membranes with the conductivity of 16, 32, and 40 pSm in 0.1 M NaCl and 168, 240, and 320 pSm in 1 M NaCl at pH 7.2. Therefore, they were attributed to the group of actinoporins.Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 1, 2005, pp. 39–48.Original Russian Text Copyright © 2005 by Ilina, Monastyrnaya, Sokotun, Egorov, Nazarenko, Likhatskaya, Kozlovskaya.  相似文献   

3.
The chromatographic behavior of a number of globular proteins was studied on a Bio-Sil TSK CM-2-SW weak cation exchange HPLC column under acidic conditions. A linear gradient of 0-1 M NH4Ac in 1 M HOAc, inducing a convex pH gradient from 2.4-4.8, resulted in an excellent separation of highly basic proteins. For these proteins a linear relationship between isoelectric point and retention time was determined experimentally. The effect of pH and the ion composition of the eluting buffer system on this linear correlation was studied. Although the exact basis for protein separation on the CM-2-SW column at low pH is not clear yet, both the pH-dependent net positive charge per unit surface area and most likely the relative percentage of arginine in the total number of basic residues contribute to this separation. Because of the high resolving power and the high protein recovery obtained in a system using only acidic volatile buffer solutions, the cation exchanger is particularly suitable for the purification of nanogram amounts of acid-stable basic growth factors. The present sterile conditions (1 M HOAc/NH4Ac system, pH less than 4) and the easy removal of salt by lyophilization facilitate the detection of these proteins by biological assays.  相似文献   

4.
Purothionin isolated from commercial wheat flour contained several components and two of them (A-I and A-II) were isolated in pure form by CM-52 column chromatography. Each component contained 45 amino acid residues with a 4 disulfide bonds. Purothionin A-II was digested with trypsin and thermolysin to isolate cystine peptides. These were separated and purified by chromatography on an SP-Sephadex column, and paper electrophoresis and chromatography. A peptide containing a -Cys-Cys- sequence was hydrolyzed with 10 N sulfuric acid. Amino acid compositions and partial sequence studies of the cystine peptides and their performic acid-oxidized peptides revealed the positions of all 4 disulfide bonds in purothionin A-II. They were formed between residues 3 and 39, 4 and 31, 12 and 29, and 16 and 25. The results of a partial study of purothionin A-I are also presented.  相似文献   

5.
Three toxins (CM-2e, CM-4a and CM-7) were purified from the venom of Naja haje annulifera by gel filtration on Sephadex and by ion-exchange chromatography on CM-cellulose. They comprise 60 amino acid residues and are cross-linked by four intrachain disulphide bridges. The complete amino acid sequences of the three toxins have been elucidated. The toxicities, the serological properties, the sequences and the invariant amino acid residues of toxin CM-2e, CM-4a and CM-7 resemble the corresponding properties of the cytotoxin group.  相似文献   

6.
Ch21 protein, a developmentally regulated chick embryo protein of 21,000 apparent molecular weight, was purified from culture medium of hypertrophic chondrocytes. The purification method included a DEAE cellulose chromatography column, a CM cellulose chromatography column and a HPLC molecular sieve column. The amino acid sequence of the amino terminal end of the protein was determined. Computer assisted analysis showed significant homology between this sequence and the amino terminal sequences of proteins that belong to the superfamily of the low molecular weight binding proteins sharing a basic framework for the binding and transport of small hydrophobic molecules. Determination of the amino terminal sequence of the chicken retinol binding protein excluded identity between this protein and the Ch21.  相似文献   

7.
Three abundant proteins of approximate molecular masses of 22, 23, and 24 kilodaltons were purified from potato (Solanum tuberosum L.) tubers by DEAE cellulose and CM-52 cellulose ion exchange column chromatography, electroelution, and high-pressure liquid chromatography (HPLC). Antibodies specific to the gel-purified 22-kilodalton protein were prepared. Immunoblot analysis showed that the 22-, 23-, and 24-kilodalton proteins are immunologically related and that these proteins are present in tubers and as higher molecular mass forms in leaves, but not in stems, roots, and stolons. The ratios of amino acid composition were compared among the three purified proteins, and the aminoterminal amino acid sequences were determined for these three proteins. All three proteins have identical amino-terminal sequences that match the deduced amino acid sequence of an abundant tuber protein cDNA.  相似文献   

8.
Toxin CM-13b was purified from the venom of Naja haje annulifera by gel filtration on Sephadex G-50 and by ion-exchange chromatography on CM-cellulose. The toxin comprises 65 amino acid residues and is cross-linked by five disulphide bridges. The complete amino acid sequence of toxin CM-13b was elucidated. The reduced and S-carboxymethylated toxin was digested with trypsin and chymotrypsin and the peptides purified by DEAE-cellulose chromatography and chromatography or electrophoresis on paper. The amino acid sequences of the intact toxin and its constituent peptides were determined by the Edman-Begg procedure, either through the use of the automatic sequenator or by manual manipulation. The chymotryptic digest provided the necessary overlapping peptides for aligning the tryptic peptides. The primary structure of toxin CM-13b shows a high degree of homology with that of protein S4C11 from Naja melanoleuca venom[1], but their toxicities are very different.  相似文献   

9.
Three toxins (CM-8, CM-11, and CM-13a) were purified from the venom of Naja haje annulifera by gel filtration on Sephadex G-50 and by ion-exchange chromatography on CM-cellulose. Whereas toxin CM-8 and CM-11 comprise 60 amino acid residues, toxin CM-13a contains 61 residues. All three toxins are cross-linked by four intrachain disulphide bridges. The complete amino acid sequences of these toxins have been elucidated. The reduced and S-carboxymethylated toxins were digested with trypsin and chymotrypsin and the peptides purified by ion-exchange chromatography, gel filtration and chromatography or electrophoresis on paper. The Edman procedure, either through the use of the automatic sequencer or by manual manipulation, was employed to obtain the sequence of the intact toxins and the pure peptides. The chymotryptic digests provided the necessary overlapping peptides which allowed the alignment of the tryptic peptides. The properties of the three toxins were compared with those of the cytotoxin group. The toxicities the serological properties, the sequences and the invariant amino acid residues of toxin CM-8 and CM-11 resemble the corresponding properties of the cytotoxin group. The sequence and serological properties of toxin CM-13a show that it is related to the cytotoxin group, but its toxicity is much lower than those encountered in the cytotoxin group.  相似文献   

10.
Two forms of chorismate mutase (EC 5.4.99.5), designated as CM-1 and CM-2, have been detected in etiolated seedlings of Sorghum bicolor after DEAE-cellulose chromatography. CM-1 and CM-2 contained 44 and 56%, respectively, of the total activity measured after DEAE-cellulose chromatography. CM-1 was activated by tryptophan and inhibited by phenylalanine and tyrosine. In contrast, CM-2 was insensitive to all three aromatic amino acids. CM-1 and CM-2 were purified 1389- and 1018-fold, respectively, by anion exchange, hydrophobic, and dye matrix chromatography. The molecular weights estimated by gel filtration on Sephacryl S-200 were 56,000 for CM-1 and 48,000 for CM-2. Subunit molecular weights of the two forms were estimated by sodium dodecyl sulfate-gel electrophoresis at 36,000 and 51,000 for CM-1 and CM-2, respectively. Tryptophan was required for the stability of CM-1 at all stages of purification. Both isoenzymes were stable at 0 or -20 degrees C and had broad pH optima (6-10 for CM-1 and 7.5-9.5 for CM-2).  相似文献   

11.
八棱丝瓜籽核糖体失活蛋白的分离纯化及其生化性质   总被引:7,自引:0,他引:7  
通过盐溶液抽提、硫酸铵分级沉淀、CM 5 2纤维素阳离子交换层析、反相毛细管液相色谱 (re verse phasecapillaryliquidchromatography ,RP CLC)等步骤 ,从八棱丝瓜籽中分离到 2种单链核糖体失活蛋白luffaculin 1和luffaculin 2 .在SDS PAGE和IEF上均显示为单一条带 ,表观分子量均为 2 8kD ,其等电点分别为 8 86 (luffaculin 1)和 9 0 5 (luffaculin 2 ) .实验表明 ,它们具有RNAN 糖苷酶活性 .蛋白质合成抑制活性测试表明 ,它们对蛋白质合成具较强的抑制作用 .体外抑制肿瘤细胞生长活性检测表明 ,luffaculin 1和luffaculin 2对人白血病细胞株K5 6 2有较强的毒性 ,IC50 分别为 1 1×10 -6mol L和 2 0× 10 -7mol L .八棱丝瓜籽核糖体失活蛋白具有可以用于或构成免疫毒素治疗癌症的应用前景  相似文献   

12.
Folded chromosomes were prepared as membrane-associated complexes from vegetative cells of Bacillus subtilis by stepwise sucrose gradient centrifugation. From nucleoids, a deoxyribonucleic acid-bound polypeptide with a molecular weight of 6,000 (P6) was purified by KCl-(NH4)2SO4 salting out, diethylaminoethyl cellulose column chromatography, and deoxyribonucleic acid cellulose column chromatography. The amino acid composition of polypeptide P6 was determined.  相似文献   

13.
A simple procedure using human basic fibroblast growth factor (FGF) was utilized for the selection of COS cell mutants with defects in the biosynthesis or expression of heparan sulfate proteoglycan (HSPG). Our approach was based on the strong binding affinity exhibited by COS cells to human basic FGF that had been adsorbed to plastic dishes. Cell binding to basic FGF could be inhibited by heparin and heparan sulfate (HS), but not by chondroitin sulfate, dermatan sulfate, keratan sulfate, or hyaluronic acid, suggesting that the cell binding involved an interaction between basic FGF and cell surface heparin-like molecules. COS cells were treated with ethyl methanesulfonate and four stable mutants were subsequently isolated that did not bind strongly to basic FGF adsorbed to plastic. These mutants cell lines (CM-2, CM-8, CM-9, and CM-15) exhibited significantly reduced 35SO4 incorporation into HS (40-70% depending on the cellular pool analyzed). In one of these cell lines, CM-15, the incorporation of [6-3H]glucosamine into HS was unaltered, suggesting that the extent of oligosaccharide polymerization was equivalent to that observed for the wild-type cells. Structural analysis revealed that N-sulfated glucosamine residues were present much less frequently in HS derived from these cells as compared with that derived from wild-type cells. Furthermore, CM-15 was found to be three-fold deficient in HS N-sulfotransferase activity, but contained wild-type levels of HS O-sulfotransferase activities.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
The hemoglobin of the Pale-Throated Three-Toed Sloth (Bradypus tridactylus, Xenarthra) was separated into two components (ratio 4:1) with identical amino-acid analyses for the alpha- and beta-chains. The primary structures of both chains from the major component are given. They could be isolated by chromatography on carboxymethyl cellulose CM-52. The sequences have been determined by automatic Edman degradation of the native chains and their tryptic peptides. The comparison with human hemoglobin showed 27 substitutions in the alpha-chains and 33 in the beta-chains. In the alpha-chains one amino-acid exchange involves an alpha 1/beta 1-contact. In the beta-chains two heme- and four alpha 1/beta 1-contacts are substituted. The hemoglobin of the Sloth is compared to that of the Nine-Banded Armadillo (Dasypus novemcinctus), another representative of the order Xenerthra.  相似文献   

15.
Etiolated mung bean seedlings were examined for chorismate mutase activity. Evidence for the occurrence of two forms of the enzyme (designated CM-1 and CM-2) was obtained by ammonium sulfate fractionation, anion exchange cellulose chromatography, and isoelectric focusing. The two forms showed distinctly different properties, as CM-1 was inhibited by phenylalanine and tyrosine and activated by tryptophan, but inhibition by phenylalanine and tyrosine was reversed by tryptophan. The other form, CM-2, was unaffected by any of the three aromatic amino acids. Isoelectric points of the two forms were CM-1, pH 4.6, and CM-2, pH 5.6. The molecular weights estimated by molecular sieving on Sephadex G-200 were CM-1, 50,000, and CM-2, 36,000.  相似文献   

16.
Two isoenzymes of chorismate mutase (EC 5.4.99.5), designated as CM-1 and CM-2, were isolated and partially purified from suspension-cultured cells of Ruta gravelens by DEAE-sephacel chromatography and gel filtration. 60–72% of the total activity measured after DEAE-sephacel chromatography were obtained as CM-1 and 28–40% were CM-2 activity. CM-1 was inhibited by phenylalanine (K1 = 4 · 10?6 M) and tyrosine (K1 = 8. 10?6M) and activated by tryptophan. In contrast, CM-2 was not influenced by these three amino acids. The molecular weights estimated by gel filtration on SEPHADEX G-150 were 56000 for CM-1 and 45000 for CM-2, respectively. Both isoenzymes were stable at ?20°C, but exhibited different behaviour during thermal inactivation and different optima of reaction temperature. CM-1 catalysed the reaction at a pH optimum of pH 7.8 and CM-2 showed a broad optimum between 6–10. The Km-values for chorismic acid were determined to be 1.1 mM for CM-1 and 0.5 mM for CM-2. The isoenzymes showed different behaviour to inhibitors of sulfhydryl groups. There were no differences in all parameters of chorismate mutase examined for two various cell lines of Ruta graveolens.  相似文献   

17.
Hemoglobin from an adult camel (Camelus dromedarius) was prepared from the red cell lysate by CM- and DEAE-cellulose chromatography. The purified hemoglobin showed a lesser mobility on starch gel electrophoresis at pH 8.5 than that of human hemoglobin C. Native camel hemoglobin contains 95-99% alkali-resistant hemoglobin and in soluble in 2.94 M K2HPO4/KH2PO4 buffer. Different forms of camel hemoglobin show similar ammonium sulfate precipitation curves. Indirect evidence for the stability of camel hemoglobin solutions was obtained from several sources. Spontaneous met-hemoglobin formation is extremely slow and minimal quantities of degradation products appear on starch gel electrophoresis and on chromatographic separation. The alpha and beta chains of camel hemoglobin A were separated on a CM-23 column by the use of a pyridine formate gradient. Large peptide fragments were obtained by tryptic digestion of maleylated alpha and beta chains. The N-terminal structure of the alpha and beta chains and of tryptic maleylated peptides derived from alpha and beta chains are presented. Between adult camel hemoglobin and adult human hemoglobin six amino acid differences in the N-terminal 20 amino acid residues of the alpha chain, at residues: 4, 5, 12, 14, 17, and 19; eight amino acid substitutions were found in the beta chain at positions: 4, 5, 6, 9, 12, 13, 16, and 19. Substitutions at alpha5 Ala leads to Lys, and beta19 Asn leads to Lys, increase the net positive charge of camel hemoglobin by two, while other substitutions result in no charge differences. The molecular basis of the stability of camel adult hemoglobin is discussed.  相似文献   

18.
An enzyme extract from Cellulase-Onozuka, a commercial product of Trichoderma viride, was fractionated by Amberlite CG-50 column chromatography into three cellulase [EC 3.2.1.4] groups, peaks I to III. A noval enzyme, which has both beta-glucosidase [EC 3.2.1.21] and exo-carboxymethyl-cellulase (exo-CMCase) properties was obtained from peak III by extensive purification throuh consecutive column chromatography. The enzyme was homogeneous on ultracentrifugation, SDS-gel and cellulose acetate film electrophoreses and molecular sieve chromatography on Bio-Gel P-150. The molecular weight of this enzyme was estimated to be 53,000. The enzyme appeared to release cellobiose residues one by one from the nonreducing end of higher cellooligosaccharides and CM-cellulose (CMC), but to release glucosyl residues from reduced cellotriose and beta-cellobioside, resembling a beta-glucosidase in this respect. Furthermore, this exo-CMCase also attacked xylan exo-wise to produce xylobiose moleculaes one by one, but it scarcely attacked insoluble cellulose, except for a cellodextrin apparently rich in amorphous structure.  相似文献   

19.
A modified method was developed to isolate lactoferrin from women's colostrum by means of ion-exchange chromatography on a Servacel CM-52 column and gel filtration on a Toyoperal HW-52 column. These changes simplified the basic method and decreased the length of the procedure without affecting the biological activity and purity of the preparation. The modified method can be recommended to produce lactoferrin suitable for the use as a pharmaceutical preparation and nutritional additive to milk substitutes.  相似文献   

20.
猪精子中与卵透明带糖蛋白ZP3结合的蛋白质   总被引:3,自引:0,他引:3  
依次经PSL-Sepharose亲和层析柱和纤维素CM-52离子交换层析柱,从猪精子的CHAPS抽提液分离得4个蛋白质组分。用固相透明带精蛋白结合试验(IZPGBA)检测;表明精子蛋白SP1和SP2具有结合透明带糖蛋白ZP3的活性,SP2并显示凝集血球的活性。精子蛋白SP1与卵预温育明显抑制精卵结合,抑制活性与加入的精子蛋白的浓度呈正相关。用生物素标记的ZP3和蛋白质印迹技术,证明SP1中的68kD精子蛋白与ZP3结合,提示68kD精子蛋白参与精卵结合。  相似文献   

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