scholarly journals Purification and characterization of polyamine oxidase from Ascaris suum

1992 ◽  
Vol 283 (1) ◽  
pp. 75-80 ◽  
Author(s):  
S Müller ◽  
R D Walter

The interconversion of polyamines in the parasite nematode Ascaris suum by a novel type of polyamine oxidase was demonstrated. The nematode enzyme was clearly distinguishable from monoamine and diamine oxidases as well as from the mammalian polyamine oxidase, as shown by the use of the specific inhibitors pargyline, aminoguanidine and MDL 72527 respectively. All three inhibitors had no effect on the parasite polyamine oxidase, and the enzyme did not accept diamines such as putrescine, cadaverine or histamine as substrates. The parasite polyamine oxidase selectively oxidizes spermine and spermidine but not N-acetylated polyamines, whereas the mammalian tissue-type polyamine oxidase shows preference for the N-acetylated polyamines. These results suggest a regulatory function of the nematode polyamine oxidase in the degradation and interconversion of polyamines in parasite nematodes. The enzyme was purified to homogeneity by gel filtration, preparative isoelectric focusing and subsequent affinity chromatography on spermine- and berenil-Sepharose 4B. With respect to reaction type, the prosthetic group FAD, the molecular mass (66 kDa) and the contents of thiol and carbonyl groups, the polyamine oxidase from A. suum is similar to the isofunctional enzyme of mammalian tissue.

1981 ◽  
Vol 46 (03) ◽  
pp. 658-661 ◽  
Author(s):  
C Korninger ◽  
J M Stassen ◽  
D Collen

SummaryThe turnover of highly purified human extrinsic plasminogen activator (EPA) (one- and two-chain form) was studied in rabbits. Following intravenous injection, EPA-activity declined rapidly. The disappearance rate of EPA from the plasma could adequately be described by a single exponential term with a t ½ of approximately 2 min for both the one-chain and two-chain forms of EPA.The clearance and organ distribution of EPA was studied by using 125I-labeled preparations. Following intravenous injection of 125I-1abeled EPA the radioactivity disappeared rapidly from the plasma also with a t ½ of approximately 2 min down to a level of 15 to 20 percent, followed by a small rise of blood radioactivity. Gel filtration of serial samples revealed that the secondary increase of the radioactivity was due to the reappearance of radioactive breakdown products in the blood. Measurement of the organ distribution of 125I at different time intervals revealed that EPA was rapidly accumulated in the liver, followed by a release of degradation products in the blood.Experimental hepatectomy markedly prolonged the half-life of EPA in the blood. Blocking the active site histidine of EPA had no effect on the half-life of EPA in blood nor on the gel filtration patterns of 125I in serial plasma samples.It is concluded that human EPA is rapidly removed from the blood of rabbits by clearance and degradation in the liver. Recognition by the liver does not require a functional active site in the enzyme. Neutralization in plasma by protease inhibitors does not represent a significant pathway of EPA inactivation in vivo.


1985 ◽  
Vol 54 (02) ◽  
pp. 485-489 ◽  
Author(s):  
Yukiyoshi Hamaguchi ◽  
Masuichi Ohi ◽  
Yasuo Sakakura ◽  
Yasuro Miyoshi

SummaryTissue-type plasminogen activator (TPA) was purified from maxillary mucosa with chronic inflammation and compared with urokinase. Purification procedure consisted of the extraction from delipidated mucosa with 0.3M potassium acetate buffer (pH 4.2), 66% saturation of ammonium sulfate, zinc chelate-Sepharose, concanavalin A-Sepharose and Sephadex G-100 gel filtration chromatographies.The molecular weight of the TPA was approximately 58,000 ± 3,000. Its activity was enhanced in the presence of fibrin and was quenched by placental urokinase inhibitor, but not quenched by anti-urokinase antibody. The TPA made no precipitin line against anti-urokinase antibody, while urokinase did.All these findings indicate that the TPA in maxillary mucosa with chronic inflammation is immunologically dissimilar to urokinase and in its affinity for fibrin.


1992 ◽  
Vol 287 (3) ◽  
pp. 911-915 ◽  
Author(s):  
G Nguyen ◽  
S J Self ◽  
C Camani ◽  
E K O Kruithof

The binding of tissue-type plasminogen activator (t-PA) to membranes prepared from human liver was investigated, and a specific, saturable, high-affinity binding site (Kd = 3.4 nM) was identified. The binding of t-PA to liver membranes was not affected by an excess of D-mannose or D-galactose, or by active urokinase (u-PA), whereas binding of t-PA to membranes prepared from human HepG2 hepatoma cells was inhibited by u-PA. HepG2-membrane-bound t-PA was fully complexed to PA inhibitor 1 (PAI-1), whereas liver-membrane-bound t-PA was not complexed. Gel filtration on Sephacryl S300 of membrane proteins solubilized in deoxycholate revealed that high-affinity t-PA binding activity elutes at an apparent molecular mass of 40 kDa. Monoclonal antibodies specific for the growth factor and the kringle 2 domains inhibited the binding of t-PA to liver membranes and the catabolism of t-PA by rat hepatoma cells. Human liver membranes also bound u-PA; binding was inhibited by pro-u-PA, the N-terminal fragment of u-PA, but not by the 33 kDa form of u-PA or by t-PA. Our results show that human liver membranes contain a specific 40 kDa binding protein for t-PA that is different from the PAI-1-dependent receptor described on HepG2 cells and the mannose receptor isolated from human liver.


1971 ◽  
Vol 19 (1) ◽  
pp. 1-15 ◽  
Author(s):  
M. HARADA ◽  
C. ISERSKY ◽  
P. CUATRECASAS ◽  
D. PAGE ◽  
H. A. BLADEN ◽  
...  

The morphology of the fibril of amyloid derived from different individuals is similar, but occasionally significant differences are noted. All human amyloid filaments have a "β-pleated sheet" conformation as revealed by x-ray diffraction, and those examined after orientation show a "cross-β" pattern. All amyloid fibril concentrates studied so far can be fractionated to obtain the major amyloid protein component(s) by sequential gel filtration with 5 M guanidine-HCl in 1 N acetic acid on Sepharose 4B and Sephadex G-100 or G-75 columns with the removal of over 28% of proteins representing minor constituents. The major amyloid protein(s) obtained from the spleen and/or liver of six patients is found to contain tryptophan, to be deficient in hydroxylysine and hydroxyproline and usually at least one commonly occurring amino acid and to have a high content of dicarboxylic acid and short chain amino acids and unreactive (blocked) NH2-terminal groups or aspartic acid-asparagine (Asx). However, the amyloid protein(s) from each individual differs from that of the others in molecular weight, in amino acid composition and in the presence or absence of specific tryptic peptides. Amyloid protein(s) from the liver and spleen of the same individual is identical. No chemical characteristics distinguish amyloid proteins derived from cases classified clinically as "primary" from those classified as "secondary." There is a striking chemical similarity between amyloid proteins and the NH2-terminal variable fragment of the light and heavy chain of immumoglobulin proteins.


1981 ◽  
Author(s):  
R Wallin ◽  
M Belew ◽  
K Ohlsson ◽  
T Saldeen

The presence of leucocytes around extravascular fibrin deposits suggests that the leucocyte elastases might be partly responsible for the extravascular degradation of fibrin. Our previous studies have shown that the degradation of fibrin(ogen) by plasmin leads to the release of 2 small peptides which markedly increase vascular permeability and induce oedema e.g. in the lungs. The results of this investigation show that small peptides released from fibrinogen after degradation by leucocytes elastases also increase vascular permeability.Human fibrinogen (Kabi, Grade L) was made plasminogenfree by affinity chromatography on Lysine-Sepharose 4B prior to use. The human leucocyte elastases were isolated from extracts of lysosome-like granules of human leukaemic myeloid cells by a combination of gel filtration, affinity chromatography and preparative agarose gel electrophoresis. The fibrinogen (0.5 %) and the leucocyte elastases (in a molar ratio of 100:1) were incubated together for 48 h at +37°C and at pH 8.5. The mixture was then cooled to +4°C to stop the lysis and ultrafiltrated on a DIAFLO PM 10 membrane until the retentate was approximately 10 % of the starting volume. The peptides in the diffusate accounted for about 20 % of the starting material as estimated from absorbance measurements at 280 nm. The diffusate was concentrated by lyophilization and fractionated by chromatography on a column of Bio-Gel P-6. At least 8 fractions were obtained of which only two showed a significant activity in their ability to increase vascular permeability in rat skin. The active peptides in these two fractions were further purified to homogeneity by column zone electrophoresis at various pHs and their amino acid compositions established.


1979 ◽  
Vol 82 (3) ◽  
pp. 383-NP ◽  
Author(s):  
M. A. AL-AWQATI ◽  
Y. B. GORDON ◽  
T. CHARD

An homogenate of human foetal adrenal gland was subjected to negative immunoabsorption by column chromatography using anti-whole human serum coupled to Sepharose 4B. Two peaks were eluted and used to immunize rabbits. The antisera produced were absorbed and tested for specificity by double immunodiffusion. Two antigens, which appeared to be specific to the adrenal gland, were identified having molecular weights of 25 000 and 65 000 as determined by gel filtration. The lower molecular weight antigen was isolated by physicochemical methods and found to be a protein. The amino acid composition is reported.


2019 ◽  
Vol 20 (10) ◽  
pp. 2434 ◽  
Author(s):  
Evgeniya E. Burkova ◽  
Alina E. Grigor’eva ◽  
Dmitrii V. Bulgakov ◽  
Pavel S. Dmitrenok ◽  
Valentin V. Vlassov ◽  
...  

Exosomes are nanovesicles (30–100 nm) containing various RNAs and different proteins. Exosomes are important in intracellular communication, immune function, etc. Exosomes from different sources including placenta were mainly obtained by different types of centrifugation and ultracentrifugations and were reported to contain from a few dozen to thousands of different proteins. First crude exosome preparations from four placentas (normal pregnancy) were obtained here using several standard centrifugations but then were additionally purified by gel filtration on Sepharose 4B. Individual preparations demonstrated different gel filtration profiles showing good or bad separation of exosome peaks from two peaks of impurity proteins and their complexes. According to electron microscopy, exosomes before gel filtration contain vesicles of different size, ring-shaped structures forming by ferritin and clusters of aggregated proteins and their complexes. After filtration through 220 nm filters and gel filtration exosomes display typically for exosome morphology and size (30–100 nm) and do not contain visible protein admixtures. Identification of exosome proteins was carried out by MS and MS/MS MALDI mass spectrometry of proteins’ tryptic hydrolyzates after their SDS-PAGE and 2D electrophoresis. We have obtained unexpected results. Good, purified exosomes contained only 11–13 different proteins: CD9, CD81, CD-63, hemoglobin subunits, interleukin-1 receptor, annexin A1, annexin A2, annexin A5, cytoplasmic actin, alkaline phosphatase, serotransferin, and probably human serum albumin and immunoglobulins. We assume that a possible number of exosome proteins found previously using crude preparations may be very much overestimated. Our data may be important for study of biological functions of pure exosomes.


1978 ◽  
Vol 173 (3) ◽  
pp. 941-947 ◽  
Author(s):  
G P Roberts

The depolymerization of bovine cervical glycoprotein resulting from cleavage of disulphide bonds. Pronase digestion and both procedures sequentially was assessed by using gel filtration. Cleavage of disulphide bonds followed by Pronase digestion produced more extensive depolymerization than did either treatment alone, and gel filtration of the products resulted in two major peaks of glycosylated material on Sepharose CL-2B and Sepharose 4B. The glycopolypeptides in both peaks had similar sugar and sulphate compositions, but they migrated to different extents on gel electrophoresis. Electrophoretic studies indicated that both glycopolypeptides were derived from the same glycoprotein molecule and not from a mixture of two similar glycoproteins. Pronase digestion of glycoproteins in which the disulphide bonds had been labelled with iodo-[1-14C]acetamide revealed that most of the cysteine residues were situated in regions susceptible to Pronase. The results show the presence of two types of structural regions in bovine cervical glycoprotein, namely ‘naked’ peptide or non-glycosylated regions and glycopolypeptide subunit regions in which glycopolypeptides of two different sizes predominate. Comparison of the cervical glycoproteins isolated from mucus secreted during oestrus and pregnancy, by the methods outlined above, did not reveal any structural differences in the glycoproteins to explain the different physical properties of the mucus secreted under these conditions.


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