scholarly journals Characterization of a proteolytic-enzyme inhibitor with allergenic activity. Multiple functions of a parasite-derived protein

1979 ◽  
Vol 177 (1) ◽  
pp. 41-47 ◽  
Author(s):  
P Willadsen ◽  
G A Riding
Keyword(s):  
Hypersensitivity Reaction ◽  
Sodium Dodecyl Sulphate ◽  
Enzyme Inhibitor ◽  
Specific Activity ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Intradermal Injection ◽  
Boophilus Microplus ◽  
Polyacrylamide Gels ◽  
Allergenic Activity

1. A trypsin inhibitor from the tick Boophilus microplus was purified by ion-exchange chromatography and gel filtration. 2. It is pure by the criteria of constant specific activity on gel filtration and by electrophoresis on polyacrylamide gels containing sodium dodecyl sulphate. 3. The protein undergoes reversible polymerization, dissociating at low pH. 4. The apparent molecular weight measured by electrophoresis on polyacrylamide gels containing sodium dodecyl sulphate is 18,500. 5. Inhibition of trypsin occurs by formation of a 1 :1 molar complex. 6. Chymotrypsin is also inhibited, though the dissociation constant of the complex formed is larger than with trypsin. The protein possesses independent sites for the inhibition of chymotrypsin and trypsin. 7. The inhibitor preparation gives an immediate hypersensitivity reaction on intradermal injection into cattle that have been exposed to the tick. The allergenic activity is due to the inhibitor protein itself and not to contaminating material, since the two activities were not separated during purification or in two subsequent affinity-chromatography procedures. 8. The hypersensitivity reaction is a true immunological response, since it is found in almost all cattle that have been exposed to the tick, but not in unexposed animals. In addition, passive cutaneous anaphylaxis can be demonstrated with serum from exposed, but not from unexposed, animals.

scholarly journals Properties of pig synovial collagenase

1980 ◽  
Vol 189 (2) ◽  
pp. 349-357 ◽  
Author(s):  
J A Tyler ◽  
T E Cawston
Keyword(s):  
Isoelectric Focusing ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Active Form ◽  
Sodium Dodecyl ◽  
Type Ii ◽  
Polyacrylamide Gels ◽  
Optimum Ph ◽  
Detectable Difference

1. Properties of a purified chemically activated form of pig synovial collagenase were examined and compared with a spontaneously active form of the enzyme. 2. The active enzyme has a specific activity of 53 000 units (microgram/min)/mg, a mol.wt. of 44 000 (by sodium dodecyl sulphate/polyarcylamide-gel electrophoresis in 2-mercaptoethanol) and pI 5.2 (by isoelectric focusing in polyacrylamide gels). 3. The activity has the characteristics of a metalloproteinase that degrades types I and III soluble or insoluble collagens in preference to type II, at an optimum pH of 6.5-8.5. 4. There is no detectable difference in these properties between the chemically activated and spontaneously active form of collagenase.

scholarly journals Purification of 5-enolpyruvylshikimate 3-phosphate synthase from Escherichia coli

1983 ◽  
Vol 213 (1) ◽  
pp. 187-191 ◽  
Author(s):  
A Lewendon ◽  
J R Coggins
Keyword(s):  
Escherichia Coli ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Polyacrylamide Gel ◽  
Purification Step ◽  
Phosphate Synthase

A procedure for the purification of 5-enolpyruvylshikimate 3-phosphate synthase from Escherichia coli is described. Homogeneous enzyme of specific activity 17.7 units/mg was obtained in 22% yield. The key purification step involves substrate elution of the enzyme from a cellulose phosphate column. The subunit Mr was estimated to be 49 000 by polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate. The native Mr was estimated to be 55 000 by gel filtration, indicating that the enzyme is monomeric.

scholarly journals Isolation of lysyl hydroxylase, an enzyme of collagen synthesis, from chick embryos as a homogeneous protein

1980 ◽  
Vol 189 (2) ◽  
pp. 247-253 ◽  
Author(s):  
T M Turpeenniemi-Hujanen ◽  
U Puistola ◽  
K I Kivirikko
Keyword(s):  
Molecular Weight ◽  
Affinity Chromatography ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Polymeric Form ◽  
Lysyl Hydroxylase ◽  
Enzyme Form

Two procedures are reported for the purification of lysyl hydroxylase, both procedures involving (NH4)2SO4 fractionation, affinity chromatography on concanavalin A-agarose and elution of the column with ethylene glycol. The additional steps in procedure A consist of gel filtration and chromatography on a hydroxyapatite column, and in procedure B of affinity chromatography on collagen linked to agarose and gel filtration. The best preparations obtained with either of the two procedures were pure when examined by sodium dodecyl sulphate-polyacrylamide-disc-gel or slab-gel electrophoresis, but about half of the preparations obtained by procedure A had minor contaminants. The specific activity of a typical preparation purified by procedure B was 13 4000 times that of the 15 000 g supernatant of the chick-embryo homogenate, with a recovery of about 4%. The molecular weight of the pure enzyme was bout 200 000 by gel filtration, and that of the enzyme subunit about 85 000 by sodium dodecyl sulphate/polyacrylamide-disc-gel or slab-gel electrophoresis. It is suggested that the active enzyme is a dimer consisting of only one type of monomer, and that a previously described enzyme form with an apparent molecular weight of about 550 000 is a polymeric form of this dimer. The catalytic-centre activity of the pure enzyme, as determined with a saturating concentration of a synthetic peptide substrate and under conditions specified, was about 3-4 mol/s per mol.

scholarly journals Multiple forms of γ-butyrobetaine hydroxylase (EC 1.14.11.1)

1984 ◽  
Vol 223 (1) ◽  
pp. 119-127 ◽  
Author(s):  
S Lindstedt ◽  
I Nordin
Keyword(s):  
Isoelectric Focusing ◽  
Sodium Dodecyl Sulphate ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Human Kidney ◽  
Polyacrylamide Gels ◽  
Multiple Forms ◽  
Bacterial Enzyme ◽  
Isoelectric Points ◽  
Liver And Kidney

gamma-Butyrobetaine hydroxylase [4-trimethylaminobutyrate, 2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating), EC 1.14.11.1] from human kidney was resolved into three forms by chromatofocusing. After further chromatography on an anion-exchanger, each form appeared as a single band on electrophoresis in polyacrylamide gel containing sodium dodecyl sulphate. The isoelectric points of isoenzymes 1, 2 and 3 were 5.6, 5.7 and 5.8 respectively, as estimated by isoelectric focusing. Their specific activities were 17-29 mu kat/g of protein. The concentrations of the three isoenzymes were about equal, possibly slightly lower for isoenzyme 1. The requirement for Fe2+ and the Km values for gamma-butyrobetaine and 2-oxoglutarate were about the same for the different enzyme forms. L- and D-Carnitine caused decarboxylation of 2-oxoglutarate to the same extent (8 and 29%) with the three forms. The enzyme forms had the same mass, 64 kDa, as determined by gel filtration in nondenaturing media. The same subunit mass, 42 kDa, was obtained for the multiple forms by electrophoresis in polyacrylamide gels containing sodium dodecyl sulphate. Isoenzyme 2 was resolved into two protein bands by isoelectric focusing in polyacrylamide gels containing urea. Isoenzyme 1 contained only one of these bands and isoenzyme 3 the other. The three enzyme forms of gamma-butyrobetaine hydroxylase thus appear to be dimeric combinations of two subunits differing in charge but not in size. gamma-Butyrobetaine hydroxylase from crude extracts of human, rat and calf liver was also separated into multiple forms by a chromatofocusing technique. The isoenzyme pattern was the same in human liver and kidney. The technique used to resolve the mammalian enzymes gave no evidence for the presence of multiple forms of the bacterial enzyme from Pseudomonas sp. AK 1.

scholarly journals Structural properties of homogeneous protein disulphide-isomerase from bovine liver purified by a rapid high-yielding procedure

1983 ◽  
Vol 213 (1) ◽  
pp. 225-234 ◽  
Author(s):  
N Lambert ◽  
R B Freedman
Keyword(s):  
Amino Acid ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Sedimentation Coefficient ◽  
Bovine Liver ◽  
Polyacrylamide Gel ◽  
Protein Disulphide Isomerase

Protein disulphide-isomerase from bovine liver was purified to homogeneity as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, two-dimensional electrophoresis and N-terminal amino acid analysis. The preparative procedure, a modification of that of Carmichael, Morin & Dixon [(1977) J. Biol. Chem. 252, 7163-7167], is much faster and higher-yielding than previous procedures, and the final purified material is of higher specific activity. The enzyme has Mr 57 000 as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, both in the presence and in the absence of thiol compounds. Gel-filtration studies on Sephadex G-200 indicate an Mr of 107 000, suggesting that the native enzyme is a homodimer with no interchain disulphide bonds. Ultracentrifugation studies give a sedimentation coefficient of 3.5S, implying that the enzyme sediments as the monomer. The isoelectric point, in the presence of 8 M-urea, is 4.2, and some microheterogeneity is detectable. The amino acid composition is comparable with previous analyses of this enzyme from bovine liver and of other preparations of thiol:protein disulphide oxidoreductases whose relation to protein disulphide-isomerase has been controversial. The enzyme contains a very high proportion of Glx + Asx residues (27%). The N-terminal residue is His. The pure enzyme has a very small carbohydrate content, determined as 0.5-1.0% by the phenol/H2SO4 assay. Unless specific steps are taken to remove it, the purified enzyme contains a small amount (5 mol/mol of enzyme) of Triton X-100 carried through the purification.

scholarly journals Effects of pronase and neuraminidase treatment on a myelin-associated glycoprotein in developing brain

1976 ◽  
Vol 156 (1) ◽  
pp. 143-150 ◽  
Author(s):  
R H Quarles
Keyword(s):  
Molecular Weight ◽  
Sialic Acid ◽  
Sodium Dodecyl Sulphate ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Apparent Molecular Weight ◽  
Weight Class ◽  
Developmental Difference ◽  
Adult Rats ◽  
Neuraminidase Treatment

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.

scholarly journals Isolation, partial purification and characterization of phospholipase A2 from Naja Katiensis venom

2021 ◽  
Vol 13 (2) ◽  
pp. 107-112
Author(s):  
C.F. Okechukwu ◽  
P.L. Shamsudeen ◽  
R.K. Bala ◽  
B.G. Kurfi ◽  
A.M. Abdulazeez
Keyword(s):  
Ion Exchange ◽  
Phospholipase A2 ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Partial Purification ◽  
Crude Venom

The most effective and acceptable therapy for snakebite victims is the immediate administration of antivenin which is limited by problems of hypersensitivity reactions in some individuals and its inability to resolve the local effects of the venom. The aim of this study was to isolate, partially purify and characterize phospholipase A2 from Naja Katiensis venom. Phospholipase A2 was partially purified via a two-step process: gel filtration on Sephadex G-75 and ion exchange chromatography using CM Sephadex, and subjected to SDS-PAGE analysis. From the results, the specific activity of the partially purified PLA2 decreased from 0.67μmol/min/mg in crude venom to 0.29μmol/min/mg after ion exchange chromatography with a yield of 5% and purification fold of 0.43. The optimum temperature of the purified PLA2 was found to be 35ºC and optimum p.H of 7. velocity studies for the determination of kinetic constants using L-a-lecithin as substrate revealed a Km  of 1.47mg/ml and Vmax  of 3.32μ moles/min/mg. The sodium dodecyl sulphate polyacrylamide gel electrophoresis of the purified PLA2 showed a distinct band with molecular weight estimated to be 14KDa. In conclusion, the present study shows that phospholipase A2 was isolated, purified and characterized. This may serve as a promising candidate for future development of a novel anti-venin drug.

scholarly journals Characterization of proteins from the cytoskeleton of Giardia lamblia

1983 ◽  
Vol 59 (1) ◽  
pp. 81-103 ◽  
Author(s):  
R. Crossley ◽  
D.V. Holberton
Keyword(s):  
Molecular Weight ◽  
Sodium Dodecyl Sulphate ◽  
Giardia Lamblia ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Molecular Size ◽  
Molecular Weights

Proteins from the axonemes and disc cytoskeleton of Giardia lamblia have been examined by sodium dodecyl sulphate/polyacrylamide gel electrophoresis. In addition to tubulin and the 30 X 10(3) molecular weight disc protein, at least 18 minor components copurify with the two major proteins in Triton-insoluble structures. The most prominent minor bands have the apparent molecular weights of 110 X 10(3), 95 X 10(3) and 81 X 10(3). Protein of 30 X 10(3) molecular weight accounts for about 20% of organelle protein on gels. In continuous 25 mM-Tris-glycine buffer it migrates mostly as a close-spaced doublet of polypeptides, which are here given the name giardins. Giardia tubulin and giardin have been purified by gel filtration chromatography in the presence of sodium dodecyl sulphate. Well-separated fractions were obtained that could be further characterized. Both proteins are heterogeneous when examined by isoelectric focusing. Five tubulin chains were detected by PAGE Blue 83 dye-binding after focusing in a broad-range ampholyte gel. Giardin is slightly less acidic than tubulin. On gels it splits into four major and four minor chains with isoelectric points in the pI range from 5.8 to 6.2. The amino acid composition of the giardin fraction has been determined, and compared to Giardia tubulin and a rat brain tubulin standard. Giardins are rich in helix-forming residues, particularly leucine. They have a low content of proline and glycine; therefore they may have extensive alpha-helical regions and be rod-shaped. As integral proteins of disc microribbons, giardins in vivo associate closely with tubulin. The properties of giardins indicate that in a number of respects - molecular size, charge, stoichiometry - their structural interaction with tubulin assemblies will be different from other tubulin-accessory protein copolymers studied in vitro.

scholarly journals Molecular Characterization of a Recombinant Manganese Superoxide Dismutase fromLactococcus lactisM4

2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
Boon Hooi Tan ◽  
Thean Chor Leow ◽  
Hooi Ling Foo ◽  
Raha Abdul Rahim
Keyword(s):  
Superoxide Dismutase ◽  
Active Sites ◽  
Manganese Superoxide Dismutase ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Maximal Activity ◽  
Gel Filtration Chromatography ◽  
T7 Promoter

A superoxide dismutase (SOD) gene ofLactococcus lactisM4 was cloned and expressed in a prokaryotic system. Sequence analysis revealed an open reading frame of 621 bp which codes for 206 amino acid residues. Expression ofsodAunder T7 promoter exhibited a specific activity of 4967 U/mg when induced with 1 mM of isopropyl-β-D-thiogalactopyranoside. The recombinant SOD was purified to homogeneity by immobilised metal affinity chromatography and Superose 12 gel filtration chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blot analyses of the recombinant SOD detected a molecular mass of approximately 27 kDa. However, the SOD was in dimer form as revealed by gel filtration chromatography. The purified recombinant enzyme had a pI of 4.5 and exhibited maximal activity at 25°C and pH 7.2. It was stable up to 45°C. The insensitivity of this lactococcal SOD to cyanide and hydrogen peroxide established that it was a MnSOD. Although it has 98% homology to SOD ofL. lactisIL1403, this is the first elucidated structure of lactococcal SOD revealing active sites containing the catalytic manganese coordinated by four ligands (H-27, H-82, D-168, and H-172).

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