Allergenic activity of some kinds of plant pollen

Allergenic active fractions of ragweed, wormwood, goosefoot and sunflower pollen with a molecular weight of 37 000, 19 000, 35 000 and 14 000, respectively, were isolated by chromatography on Sephadex. All studied allergens had similar properties: affinity to Sephadex which was more pronounced to Sephadex G-75 than to G-100; absorbing components had no activity; allergenic and antigenic activities were determined only in fractions eluted in the bed volume of the column. Affinity of the allergans to Sephadex did not depend on the eluent type, but decreased in potentiation of the buffer ionic strength.     

Purification and partial characterization of a putative mediator of insulin action on cyclic AMP-dependent protein kinase

Summary An insulin mediator which inhibits cAMP-dependent protein kinase has been purified approximately 1 000 2 000-fold from skeletal muscle. Following heat treatment, charcoal adsorption and Sephadex G-25 sieving, Sephadex G-15 sieving and HPLC over an anion exchange column were performed. The mediator has characteristics of a relatively low molecular weight peptide or derivatized peptide which acts on cAMP-dependent protein kinase but not on mitochondrial pyruvate dehydrogenase.     

Characterization of multiple forms of histone phosphatase in rat liver.

By using chromatography on DEAE-cellulose, aminohexyl-Sepharose 4B and Sephadex G-200, rat liver extract was shown to contain at least three fractions, IA, IB and II, of histone phosphatase. Fractions IA and II are probably the same enzymes as the previously described glycogen synthase phosphatase and phosphorylase phosphatase, respectively, but IB exhibits noticeable activities only with phosphohistone as substrate. Approximate molecular weights of 69 000, 300 000 and 160 000 were determined by gel filtration on Sephadex G-200 for IA, IB and II, respectively.     

Further studies on bovine serum amylase. 3. Affinity chromatography

The major bovine serum isoamylases controlled by the AmI locus have been examined by gel filtration. On Sephadex G-200 the isoamylases can be resolved into two classes. The AmI A and AmI B have apparent molecular weights of 307 000 daltons whilst the AmI C isozyme has an apparent molecular weight of 44 400 daltons. The separation of the isozymes into two classes according to their elution behaviour on Sephadex G-200 has been shown to be an affinity separation. All three AmI isozymes are eluted from a non-dextran media (BioGel A1.5m) with apparent molecular weights of 417 000 daltons. The affinity separation on Sephadex G-200 has been shown to be inhibited by the addition of 1% (w/v) maltose to the elution buffer. In the presence of 1 % (w/v) maltose all three AmI isozymes are coeluted from Sephadex G-200 with apparent molecular weights of 321000 daltons. The maltase and amylase activities of the AmI isozymes were eluted coincidentally under all the conditions studied.     

Humic-like substances of bacterial origin. II. Fractionation of the bacterial humic-like substances by gel filtration on sephadex gels.

Humic-like substances obtained from cells of Pseudomonas acidovorans were separated on Sephadex G-25 into two groups of substances of different molecular weight. The substances of the molecular weight greater than 5000 were successively separated on Sephadex gels G-50, G-75, G-100. Five fractions of different molecular weight were obtained, the percentage of which varied depending on the media used and time of incubation of the bacteria. Most (38%--46%) of the compounds contained in the bacterial humic acids were of approximate molecular weight of 40 000--50 000. The distribution of the fractions in the bacterial "humic-acids" was compared with those of the humic acid made by Fluka A. G. The synthetic humic acid contained most (approximately 40%) of the compounds of approximate molecular weight of 8000--10 000. In the bacterial and synthetic material the content of the compounds with the molecular weight above 100 000 was very similar (8%--12%).     

Zinc binding in cow''s milk and human milk

In both cow's milk and human milk, zinc was associated with proteins of high molecular weight (greater than 100 000), as judged by analysis with Sephadex G-75. Precipitation of the casein at pH 4.6 and filtration of the resultant acid whey on Sephadex G-25 led, however, to the recovery of about 90% of the zinc as a compound of low molecular weight, which was tentatively identified as zinc citrate. Over 95% of the zinc of cow's milk was sedimented with the casein micelles on ultracentrifugation. Filtration of these micellar caseins on Sephadex G-150 gave two peaks containing zinc, which corresponded to aggregates of alpha-casein-kappa-casein and of alpha-casein-beta-casein. Ultracentrifugation of human milk sedimented only approx. 40% of total zinc. Analysis of sediment and supernatant on Sephadex G-150, however, indicated that about 85% of the zinc was associated with a protein complex of molecular weight greater than 150 000. The major protein of this complex was identified as lactoferrin. A minor zinc-binding component of average molecular weight 30 000 was also observed in the supernatant. The results indicated that zinc is bound to different macromolecules in cow's and human milk. This may be a factor affecting the bioavailability to the human infant of zinc from the two milks, and it is suggested that in human milk lactoferrin may be involved in the uptake of zinc.     

Purification of multiple forms of adenosine deaminase from rabbit intestine.

Two forms of adenosine deaminase (adenosine aminohydrolase, EC 3.5.4.4), differing in molecular size, have been purified and obtained in homogeneous form from rabbit intestine. The purification procedures involved extraction with acetate buffer, pH 5.5, precipitation and fractional reextraction with (NH4)2SO4, ion-exchange chromatography on DEAE-cellulose and gel filtration on Sephadex G-75 and Sephadex G-200. Gel filtrations analysis gave molecular weight estimates of 265 000 and 32 000 for the large and small deaminases respectively. The two enzymes forms had similar pH optima and pH stability ranges.     

韭菜线粒体锰超氧化物歧化酶纯化及性质研究

经硫酸铵沉淀、ＤＥＡＥ－Ｓｅｐｈａｃｅｌ层析和Ｓｅｐｈａｄｅｘ Ｇ－２００凝胶过滤,将韭菜线粒体ＳＯＤ纯化到均一程度。从６０００ｇ韭菜叶片线粒体中纯化得到２．５ｍｇ酶,酶比活力达１２００Ｕ／ｍｇ蛋白。该酶对ＫＣＮ和Ｈ２Ｏ２都不敏感,热稳定性弱 外光区吸收峰在２８０ｎｍ,凝胶过滤法测得其分子量为８２００Ｄ,ＳＯＳ－ＰＡＧＥ法测定其亚基分子量的２２０００Ｄ,ＤＮＳ法测得其Ｎ－末端氨基酸为缬氨酸。上述结     

Thermal stability of ribosomal ribonucleic acid from baby hamster kidney cells

1. RNA has been prepared from baby hamster kidney cells by extraction with a phenol–EDTA mixture and further purified by passing through a column of Sephadex G-25 that had been equilibrated with water. 2. Aging of the total RNA extracts at 4° or heating at 95° followed by rapid cooling caused a conversion of 28s RNA into material sedimenting in sucrose gradients at approx. 18s. 3. When heated RNA was re-extracted with phenol the sedimentation profile was not returned to that of the unheated RNA. 4. The 28s and 18s RNA fractions were collected separately from sucrose gradients by precipitation with 2vol. of ethanol and passed through a Sephadex G-25 column equilibrated with water. 5. Heat treatment of purified 28s RNA at 95° caused the sedimentation coefficient to increase to approx. 40s, whereas similar treatment of 18s RNA caused no significant increase. If the RNA was heated before the Sephadex G-25 treatment the sedimentation coefficient of the 28s and 18s RNA decreased to approx. 12s and 8s. 6. Heating mixtures of purified 28s and 18s RNA at 95° caused some aggregation of 18s material with the 28s fraction.     

5-Oxoprolinase from rat kidney, II. Molecular weight determinations.

The molecular weight of 5-oxoprolinase from rat kidney was estimated by gel filtration on Sephadex G-200 and G-150 to be 460 000 +/- 30 000. A value of 230 000 +/- 10 000 was obtained by zonal sedimentation in a sucrose gradient. Polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate yielded a molecular weightof 115 000 +/- 6 000. It is concluded that 5-oxoprolinase consists of four subunits of 115 000 daltons each. The dissociation or aggregation behavior of the enzyme seems to be influenced neither by the presence of the substrates 5-oxo-L-proline and MgATP2theta nor by the presence of the stabilizing compounds glutathione mercaptoethanol or dithioerythritol.     

Characterization of the multiple forms and main component of dextransucrase from Leuconostoc mesenteroides NRRL B-512F

Multiple forms of dextransucrase (sucrose:1.6-alpha-D-glucan 6-alpha-D-glucosyltransferae EC 2.4.1.5) from Leuconostoc mesenteroides NRRL B-512F strain were shown by gel filtraton and electrophoretic analyses. Two components of enzyme, having different affinities for dextran gel, were separated by a column of Sephadex G-100. The major component voided from the Sephadex column was treated with dextranase and purified to an electrophoretically homogeneous state. The ]urified enzyme had a molecular weight of 64 000-65 000, pI value of 4.1, and 17% of carbohydrate in a molecule. EDTA showed a characteristic inhibition on the enzyme while stimulative effects were observed by the addition of exogenous dextran to the incubation mixture. The enzyme activity was stimulated by various dextrans and its Km value was decreased with increasing concentration of dextran. The purified enzyme showed no affinity for a Sephadex G-100 gel, and readily aggregated after the preservation at 4 degrees C in a concentrated solution.     

Characterization of two acid proteinases found in rabbit skin homografts.

Two types of acid proteinase activity found in rabbit skin homografts were characterized by studying the effect of temperature, pH and polyacrylamide-gel electrophoresis. Their chromatographic behaviour was characterized on DEAE-cellulose, Sephadex G-75, G-100 and G-200, and their molecular weights were estimated by gel filtration. One of the acid proteinases in the homograft resembled cathepsin D (EC 3.4.23.5) of normal skin. The other acid proteinase differed from cathepsin D with respect to heat inactivation, pH optimum and molecular weight; it was not inactivated on heating at 60 degrees C for 60 min, its pH optimum was 2.5 and its molecular weight measured by Sephadex G-100 chromatography was 100 000. In all these respects, the heat-stable proteinase resembles cathepsin E (EC 3.4.23.5) of rabbit polymorphonuclear leucocytes.     

Lymphokines which influence electrophoretic mobility of macrophages.

Supernatants of blood lymphocytes from immunized guinea pigs after incubation with purified protein derivative (PPD) were fractionated on Sephadex G-75. The fractions were tested for activity to change the electrophoretic mobility of macrophages. Dependent on incubation time, three different regions of activity with an average molecular weight of 13 000, 40 000 and more than 100 000 were estimated.     

An adenosine 3':5' monophosphate dependent protein kinase from sea urchin spermatozoa.

A cyclic AMP dependent protein kinase (EC 2.7.1.37) from sea urchin sperm as purified to near homogeneity and characterized. A 68-fold purification of the enzyme was obtained. This preparation had a specific activity of 389 000 units/mg protein with protamine as the substrate. On the basis of the purification required, it may be calculated that the protein kinase constitutes as much as 1.5% of the soluble protein in sperm. There appeared to be a single form of the enzyme in sea urchin sperm, based on the behavior of the enzyme during DEAE-cellulose and Sephadex G-200 column chromatography. Magnesium ion was required for enzyme activity. The rate of phosphorylation of protamine was stimulated 2.5-fold by an optimal concentration of 0.9 M NaCl. The Km for ATP (minus cyclic AMP) was 0.119 +/- 0.013 (S.D.) and 0.055 mM +/- 0.009 (S.D.) in the presence of cyclic AMP. The specificity of the enzyme toward protein acceptors, in decreasing order of phosphorylation, was found to be histone f1 protamine, histone f2b, histone f3 and histone f2a; casein and phosvitin were not phosphorylated. The holoenzyme was found to have an apparent molecular weight of 230 000 by Sephadex G-200 chromatography. In the presence of 5 - 10(-6) M cyclic AMP, the holoenzyme was dissociated on Sephadex G-200 to a regulatory subunit of molecular weight 165 000 and a catalytic subunit of Mr 73 000. The dissociation could also be demonstrated by disc gel electrophoresis in the presence and absence of cyclic AMP.     

Solubilization of angiotensin I-coverting enzyme from rabbit lung using trypsin treatment.

The solubilization of angiotensin I-converting enzyme (peptidyldipeptide hydrolase, EC 3.4.15.1) from rabbit lung was carried out using trypsin treatment. A good recovery of 76% was obtained. The enzyme from solubilized fraction was purified using colums of Sephadex G-200, hydroxyapatite and DEAE-cellulose. The purified enzyme was shown to convert angiotensin I to angiotensin II and also to inactivate bradykinin. The specific activity of the enzyme was 24.3 units/mg protein for hippurylhistidylleucyl hydroxide and 0.182 mumol/min per mg protein for angiotensin I. The enzymic activity obtained after trypsin treatment for 5 h could be divided into two components: (i) an enzyme of molecular weight 300 000 (peak II) and (ii) an enzyme of molecular weight 145 000 (peak III), by Sephadex G-200 gel filtration. The molecular weight of the denatured enzyme was found to be 155 000 by disc gel electrophoresis in the presence of sodium dodecyl sulfate. Km values of peak II and peak III fraction for Hippuryl-His Leu-OH were 2.6 mM.     

Sephadex-binding RNA ligands: rapid affinity purification of RNA from complex RNA mixtures

Sephadex-binding RNA ligands (aptamers) were obtained through in vitro selection. They could be classified into two groups based on their consensus sequences and the aptamers from both groups showed strong binding to Sephadex G-100. One of the highest affinity aptamers, D8, was chosen for further characterization. Aptamer D8 bound to dextran B512, the soluble base material of Sephadex, but not to isomaltose, isomaltotriose and isomaltotetraose, suggesting that its optimal binding site might consist of more than four glucose residues linked via alpha-1,6 linkages. The aptamer was very specific to the Sephadex matrix and did not bind appreciably to other supporting matrices, such as Sepharose, Sephacryl, cellulose or pustulan. Using Sephadex G-100, the aptamer could be purified from a complex mixture of cellular RNA, giving an enrichment of at least 60 000-fold, compared with a non-specific control RNA. These RNA aptamers can be used as affinity tags for RNAs or RNA subunits of ribonucleoproteins to allow rapid purification from complex mixtures of RNA using only Sephadex.     

Purification of angiotensin I-converting enzyme from human lung.

Angiotensin I-converting enzyme (peptidyl dipeptide hydrolase, EC 3.4.15.1) was solubilized from the membrane fraction of human lung using trypsin treatment and purfied using columns of DE 52-cellulose, hydroxyapatite and Sephadex G-200. The purified enzyme was shown to convert angiotensin I to angiotensin II and also to inactivate bradykinin. The specific activity of the enzyme was 9.5 units/mg protein for Hippuryl-His-Leu-OH and 0.665 mumol/min per mg protein for angiotensin I. The enzymic activity obtained after trypsin treatment (1 mg/200 mg protein) for 2 h could be divided into three components: (i) an enzyme of molecular weight 290 000 (peak I), (ii) an enzyme of molecular weight 180 000 (peak II) and (iii) an enzyme of molecular weight 98 000 (peak III), by columns of DE 52-cellulose and Sephadex G-200. Km values of peak I, II and III fraction for Hippuryl-His-Leu-OH were identical at 1.1 mM. pH optimum of the enzyme was 8.3 for Hippuryl-His-Leu-OH.     

An antigen common to a wide range of bacteria. I. The isolation of a 'common antigen' from Pseudomonas aeruginosa

In crude water-soluble extracts of Pseudomonas aeruginosa 64 antigens can be demonstrated by crossed immunoelectrophoresis in agarose with polyvalent Pseudomonas-immunoglobulin. One of these antigens cross-reacts with antigens prepared from bacteria of a wide range of taxonomic groups. Monospecific immunoglobulins to this antigen (Common Antigen) were produced by immunization with the appropriate immunocomplex extracted from agarose. Common Antigen was purified by the combination of two fractionation methods: Precipitation of the crude extract with 18% (w/v) sodium sulfate, followed by gel filtration of the supernatant on a Sephadex G-200 column. By this method, 35% of Common Antigen from the crude extract was recovered, more than half of the fractions electrophoretically pure. Electrophoresis of reduced Common Antigen on a dodecyl sodium sulfate polyacrylamide gel revealed two protein bands with apparent molecular weights of 59-62 000 and 62-65 000, respectively. The untreated antigen, however, passed a column of Sephadex G-200 with the void volumen, indicating a substance of high molecular weight (> 4-600 000).     

A latent collagenase from rheumatoid synovial fluid. Purification and partial characterization

1. A latent collagenase (EC 3.4.24.3) has been isolated from rheumatoid synovial fluids and purified by (NH4)2SO4 precipitation and column chromatography, utilising Sephadex G-150, DEAE Sephadex A-50 and Sephadex G-100 superfine grade. 2. The final preparation activated by trypsin (EC 3.4.21.4) had a specific activity against thermally reconstituted collagen fibrils of 259 micrograms collagen degraded/min per mg enzyme protein, representing a nearly 800-fold increase over that of the original rheumatoid synovial fluid. 3. The latent collagenase preparation can be activated by trypsin and to some extent by HgCl2 but not by 3 M NaSCN, 3.5 M NaCl, 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) or p-chloromercuribenzoate. 4. Inhibition studies and the acrylamide gel electrophoretic pattern of collagen degradation products showed that the trypsin-activated enzyme has the essential features of a neutral collagenase. 5. The molecular weights, determined by calibrated gel filtration, were 52 000 and 43 000 for the latent and the activated enzyme, respectively. 6. The nature of the latency of synovial fluid collagenase is discussed.     

浒苔多糖的分离、纯化和分析

浒苔（Ｅｎｔｅｒｏｍｏｒｐｈａｐｒｏｌｉｆｅｒａ）经热水提取,Ｓｅｖａｇｅ法除去蛋白质,用乙醇沉淀,ＳｅｐｈａｄｅｘＧ－１００柱层析,得浒苔多糖（简称ＥＰ）精制品。经ＳｅｐｈａｄｅｘＧ－２００柱层析鉴定为单一对称性洗脱峰。红外光谱分析具有多糖特征吸收峰,紫外光谱分析未见有核酸和蛋白质的特征吸收峰。总糖含量为８８．８％,其中糖醛酸含量为３３．６％。单糖组成为Ｌ－阿拉伯糖、Ｌ－岩藻糖、Ｄ－甘露糖、Ｄ－半乳糖及Ｄ－葡萄糖,平均分子量为２５０００。