scholarly journals Purification and properties of a kininogenin from the venom of Vipera ammodytes ammodytes

1976 ◽  
Vol 153 (2) ◽  
pp. 409-414 ◽  
Author(s):  
G S Bailey ◽  
R A Shipolini

A kininogenin (EC 3.4.21.8) was purified from the venom of Vipera ammodytes ammodytes (European sand viper) by a combination of gel filtration and ion-exchange chromatography. The enzyme is approximately six times more active than bovine trypsin in its ability to release vasoactive peptides from a plasma precursor. The kininogenin is a glycoprotein containing 18-20% by weight of carbohydrate. It showed a mol. wt. of 40500 on gel filtration. Gel electrophoresis of the reduced sample in the presence of sodium dodecyl sulphate and 2-mercaptoethanol revealed the presence of two major components of mol.wt. 34300 and 31300. The heterogeneity, which was also observed on disc electrophoresis, was removed by incubation with neuraminidase. After incubation with neuraminidase the kininogenin retained full enzymic activity and possessed an isoelectric point of pH7.2. The carbohydrate content has been decreased to 10% by weight, and the single component seen on electrophoresis in the presence of sodium dodecyl sulphate and 2-mercaptoethanol corresponded to a mol.wt. of 29500.

1982 ◽  
Vol 207 (1) ◽  
pp. 133-138 ◽  
Author(s):  
M G Battelli ◽  
E Lorenzoni

A new GSSG-dependent thiol:disulphide oxidoreductase was extensively purified from rat liver cytosol. The enzymic protein shows molecular weight 40 000 as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, and 43 000 as determined by thin-layer gel filtration on Bio-Gel P-100. The pI is 8.1. This enzyme converts rat liver xanthine dehydrogenase into an oxidase, in the presence of oxidized glutathione. Other disulphide compounds are either inactive or far less active than oxidized glutathione in the enzymic oxidation of rat liver xanthine dehydrogenase. The enzyme also catalyses the reduction of the disulphide bond of ricin and acts as a thioltransferase and as a GSH:insulin transhydrogenase. The enzymic activity was measured in various organs of newborn and adult rats.


1974 ◽  
Vol 77 (3) ◽  
pp. 485-497 ◽  
Author(s):  
P. A. Torjesen ◽  
T. Sand ◽  
N. Norman ◽  
O. Trygstad ◽  
I. Foss

ABSTRACT Highly purified human LH, FSH and TSH were isolated from batches of 300 frozen pituitary glands (200 g) by pH, acetone and ethanol fractionation, Sephadex gel filtration, ion-exchange chromatography on DEAE-cellulose and CM-Sephadex, and preparative polyacrylamide-gel electrophoresis. Sodium dodecyl-sulphate (SDS) polyacrylamide gel electrophoresis was used in order to check the purity, the identity and the molecular weight of the purified LH, FSH and TSH. This procedure showed that the hormone preparations consisted of two subunits with molecular weights of: LH: 21 300 and 17 900, FSH: 22 100 and 18 300 and TSH: 20 800 and 16 400. The purity of the hormone preparations was also evaluated by analytical disc electrophoresis at pH 8.9. The purified hormone preparations had radioimmunological activity as follows: LH: 20 000 IU/mg, FSH: 16 500 IU/mg and TSH: 5 IU/mg. All preparations had high biological potency.


1981 ◽  
Vol 59 (11-12) ◽  
pp. 916-920 ◽  
Author(s):  
Hugh S. Keeping ◽  
Shioko Kimura ◽  
Jane Lovsted ◽  
Peter H. Jellinck

Peroxidase was purified 3700-fold from homogenates of estradiol-treated rat uteri by affinity chromatography on concanavalin A (ConA) – Sepharose followed by gel filtration on Bio-Gel P-150 with high recovery of enzyme. A single protein (molecular weight (MW) 45 000) staining for heme was shown by sodium dodecyl sulfate – polyacrylamide gel electrophoresis to be present in the peak fractions of enzymic activity eluted from the ConA–Sepharose column. This protein had the same mobility as bovine lactoperoxidase (MW 78 000) in a cationic gel electrophoretic system under nondenaturing conditions. Peroxidase activity in a NaCl extract of the uterus was lower than that in a CaCl2 extract but was unaffected by prolonged storage at −20 °C. In contrast, the CaCl2-extracted enzyme lost much, of its activity under these conditions by a process which could be prevented by the addition of glycerol. The sulfhydryl reagent, N-ethylmaleimide, which caused a marked increase in the activity of uterine peroxidase, provided only partial protection against inactivation during storage of CaCl2 extracts of this enzyme at low temperature.


1977 ◽  
Vol 167 (3) ◽  
pp. 693-701 ◽  
Author(s):  
Peter Hechtman ◽  
Dorothy LeBlanc

Human liver extracts contain an activating protein which is required for hexosaminidase A-catalysed hydrolysis of the N-acetylgalactosaminyl linkage of GM2 ganglioside [N-acetylgalactosaminyl-(N-acetylneuraminyl) galactosylglucosylceramide]. A partially purified preparation of human liver hexosaminidase A that is substantially free of GM2 ganglioside hydrolase activity is used to assay the activating protein. The proceudres of heat and alcohol denaturation, ion-exchange chromatography and gel filtration were used to purify the activating protein over 100-fold from crude human liver extracts. When the purified activating protein is analysed by polyacrylamide-gel disc electrophoresis, two closely migrating protein bands are seen. When purified activating protein is used to reconstitute the GM2 ganglioside hydrolase activity, the rate of reaction is proportional to the amount of hexosaminidase A used. The activation is specific for GM2 ganglioside and and hexosaminidase A. The activating protein did not stimulate hydrolysis of asialo-GM2 ganglioside by either hexosaminidase A or B. Hexosaminidase B did not catalyse hydrolysis of GM2 ganglioside with or without the activator. Kinetic experiments suggest the presence of an enzyme–activator complex. The dissociation constant of this complex is decreased when higher concentrations of substrate are used, suggesting the formation of a ternary complex between enzyme, activator and substrate. Determination of the molecular weight of the activating protein by gel-filtration and sedimentation-velocity methods gave values of 36000 and 39000 respectively.


1985 ◽  
Vol 232 (1) ◽  
pp. 151-160 ◽  
Author(s):  
G J Hart ◽  
A R Battersby

Uroporphyrinogen III synthase (co-synthetase) purified from Euglena gracilis is a monomer of Mr 38 500 by gel-filtration studies and 31 000 by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The pI is apparently in the range 4.8-5.1. No evidence for any cofactors was found, and folate derivatives were shown to be absent; no metal ions appear to be present in the enzyme. The Km for hydroxymethylbilane is in the range 12-40 microM, and the product, uroporphyrinogen III, is an inhibitor. Modification studies suggest that arginine residues are essential for the activity of co-synthetase; lysine residues may also be essential, but histidine, cysteine and tyrosine residues are not.


1976 ◽  
Vol 159 (3) ◽  
pp. 707-713 ◽  
Author(s):  
I W Davidson ◽  
I W Sutherland ◽  
C J Lawson

An unidentified pseudomonad isolated by enrichment procedures from decomposing seaweed was grown in defined medium containing sodium alginate as the sole carbon source. The alginate lyase recovered from disrupted bacterial cells was purified by a procedure of (NH4)2SO4 precipitation, gel filtration and ion-exchange chromatography. From sodium dodecyl sulphate/polyacrylamide-gel-electrophoresis experiments a mol.wt. of about 50 000 was determined. The enzyme was active against both algal and bacterial alginate preparations. Kinetic studies together with analysis of the unsaturated oligouronide products of alginate lyase action indicated the enzyme was specific for guluronic acid-containing regions of the macromolecular substrate. The specificity of the enzyme can be used to give information about the primary composition of alginate samples.


1975 ◽  
Vol 151 (3) ◽  
pp. 645-653 ◽  
Author(s):  
Z Werb ◽  
J J Reynolds

1. A specific collagenase from the culture medium of rabbit synovial fibroblasts was purified by gel filtration and ion-exchange chromatography. 2. The enzyme was homogenous on polyacrylamide-gel electrophoresis and showed only traces of contaminants when tested in gels with a non-specific antiserum. 3. The rabbit fibroblast collagenase could hydrolyse collagen both in solution and in fibrillar form. Viscometry showed that at 35°C the purified enzyme could hydrolyse >50 nmol of collagen/min per mg of enzyme. 4. The purified collagenase cleaved collagen in solution at either 24°or 35°C into the characteristic 1/4 and 3/4-length fragments. However, as compared with the impure enzyme, the purified enzyme at 35°C had a much decreased capacity to further degrade the initial specific cleavage products. 5. The specific rabbit collagenase had a mol. wt. of approx. 32000 as estimated by sodium dodecyl sulphate-polyacrylamide-gel electrophoresis, and 35000 by gel filtration.


1977 ◽  
Vol 167 (1) ◽  
pp. 71-75 ◽  
Author(s):  
R F Matagne ◽  
J P Schlösser

Argininosuccinate lyase (EC 4.3.2.1) was purified by (NH4)2SO4 fractionation, chromatography on DEAE-cellulose and gel filtration on Sephadex G-200. The final enzyme preparation was purified 46-fold compared with the crude extract. Electrophoresis of this preparation revealed three bands, the major one having the enzyme activity. Analysis of the enzyme by gel filtration and by disc electrophoresis (in two different concentrations of acrylamide) gave mol.wts. of 200000 (+/- 15000) and 190000 (+/- 20000) respectively. Treatment with sodium dodecyl sulphate and mercaptoethanol dissociated the enzyme into subunits of mol.wt. 39000 (+/-2000). The results are indicative of the multimeric structure of the enzyme, which is composed of five (perhaps four or six) identical subunits.


1997 ◽  
Vol 324 (3) ◽  
pp. 951-956 ◽  
Author(s):  
Jianxin REN ◽  
Francis J. CASTELLINO ◽  
Roger K. BRETTHAUER

An α-mannosidase II-like activity was identified in baculovirus-infected Spodoptera frugiperda (IPLB-SF21-AE) cells. The enzyme responsible was purified from Golgi-type membranes to apparent homogeneity by using a combination of steps including DEAE-cellulose, hydroxyapatite, concanavalin A–Sepharose and gel filtration chromatography. The molecular mass of this purified protein was approx. 120 kDa by SDS/PAGE under reducing conditions and approx. 240 kDa under non-reducing conditions, indicating that the enzyme is a disulphide-linked dimer. Substrates demonstrated to undergo hydrolysis with this enzyme were GlcNAc-Man5-GlcNAc-GlcNAc (non-reduced and reduced) and p-nitrophenyl α-d-mannopyranoside. The oligosaccharide substrate was converted into GlcNAc-Man3-GlcNAc-GlcNAc through an intermediate GlcNAc-Man4-GlcNAc-GlcNAc. Treatment of the isolated intermediate oligosaccharide with endoglycosidase H resulted in its conversion into GlcNAc-Man4-GlcNAc. This indicated that it contained the α-1,3-linked mannose residue on the α-1,6-linked mannose arm and showed that the α-1,6-linked mannose residue on the α-1,6-linked mannose arm had been preferentially hydrolysed by the mannosidase. The oligosaccharide lacking the β-1,2-linked GlcNAc residue on the α-1,3-linked mannose arm (Man5-GlcNAc-GlcNAc) was not hydrolysed in the presence of the enzyme. Metal ions were not required for enzymic activity on any of the substrates, but Cu2+ was strongly inhibitory. The activity of the enzyme was inhibited at low concentrations of swainsonine, but much higher concentrations of 1-deoxymannojirimycin were required to achieve inhibition. All of these properties are characteristic of mannosidase II enzymes from other eukaryotic tissues. The presence of mannosidase II in lepidopteran insect cells would allow entry of N-linked glycoproteins into the complex processing reaction pathway or into the terminal Man3-GlcNAc-GlcNAc pathway.


1976 ◽  
Vol 156 (1) ◽  
pp. 143-150 ◽  
Author(s):  
R H Quarles

Rats (14 days old) were injected with [14c]fucose and young adult rats with [3H]fucose in order to label the myelin-associated glycoproteins. As previously reported, the major [14C]fucose-labelled glycoprotein in the immature myelin had a higher apparent molecular weight on sodium dodecyl sulphate/polyacrylamide gels that the [3H]fucose-labelled glycoprotein in mature myelin. This predominant doubly labelled glycoprotein component was partially purified by preparative gel electrophoresis and converted to glycopeptides by extensive Pronase digestion. Gel filtration on Sephadex G-50 separated the glycopeptides into several clases, which were designted A,B, C AND D, from high to low molecular weight. The 14C-labelled glycopeptides from immature myeline were enriched in the highest-molecular-weight class A relative to the 3H-labelled glycopeptides from mature myelin. Neuraminidase treatment of the glycoprotein before Pronase digestion greatly decreased the proportion of glycopeptides fractionating in the higher-molecular-weight classes and largely eliminated the developmental differences that were apparent by gel filtration. However, neuraminidase treatment did not decrease the magnitude of the developmental difference revealed by electrophoresing the intact glycoprotein on sodium dodecyl sulphate gels, although it did decrease the apparent molecular weight of the glycoprotein from both the 15-day-old and adult rats by an amount comparable in magnitude to that developmental difference. The results from gel filtration of glycopeptides indicate that there is a higher content of large molecular weight, sialic acid-rich oligosaccharide units in the glycoprotein of immature myelin. However, the higher apparent molecular weight for the glycoprotein from 15-day-old rats on sodium dodcyl sulphate gels is not due primarily to its higher sialic acid content.


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