The phosphatidyl-myo-inositol-4,5-bisphosphate phosphatase from Crithidia fasciculata

1981 ◽  
Vol 59 (7) ◽  
pp. 469-476 ◽  
Author(s):  
F. B. St. C. Palmer
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Phosphate Esters ◽  
Relative Mass ◽  
Crithidia Fasciculata ◽  
Specific Activities ◽  
Triton X

The phosphatase which specifically removes one phosphate group from phosphatidyl-myo-inositol 4,5-bisphosphate was purified up to 6000-fold from the cytosol of the protozoan Crithidia fasciculata. Lipoproteins which interfere with the purification were precipitated by reducing the pH to 4.5. The enzyme was isolated from the supernatant by ammonium sulfate fractionation, gel filtration (Sepharose CL-6B), ion–exchange chromatography (DEAE-Sepharose CL-6B), and hydrophobic chromatography on detergent-saturated phenyl-Sepha-rose CL-4B. The preparations had specific activities of 44–110 μmol∙min−1∙mg protein−1 with phosphatidyl-myo-inositol 4,5-bisphosphate, but were inactive with a variety of lipid and nonlipid phosphate esters. The enzyme was stable in the presence of salt and exhibited a relative mass of 117 000. It formed larger aggregates in the absence of salt and was dissociated into monomers of relative mass 57 000 by sodium dodecyl sulfate.Addition of Triton X-100 to the assay mixture reduced the dependence upon moderation of the charge of the substrate by cetyltrimethylammonium bromide. In the presence of both detergents the Mg2+ dependence of the enzyme was reduced (Km for Mg2+ = 40 μM) while the "apparent" Km for the substrate was unchanged at 240 μM. Substrate precipitation at higher Mg2+ concentrations was eliminated.

scholarly journals Salivary apyrase of Rhodnius prolixus. Kinetics and purification

1986 ◽  
Vol 233 (3) ◽  
pp. 885-891 ◽  
Author(s):  
J J F Sarkis ◽  
J A Guimarães ◽  
J M C Ribeiro
Keyword(s):  
Atp Hydrolysis ◽  
Competitive Inhibition ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Rhodnius Prolixus ◽  
Exchange Chromatography ◽  
Phosphate Esters ◽  
Inorganic Pyrophosphatase ◽  
Blood Sucking ◽  
Specific Activities

The salivary apyrase activity of the blood-sucking bug Rhodnius prolixus was found to reside in a true apyrase (ATP diphosphohydrolase, EC 3.6.1.5) enzyme. The crude saliva was devoid of 5′-nucleotidase, inorganic pyrophosphatase, phosphatase and adenylate kinase activities. ATP hydrolysis proceeded directly to AMP and Pi without significant accumulation of ADP. Km values for ATP and ADP hydrolysis were 229 and 291 microM respectively. Ki values for ATP and ADP inhibition of ADP and ATP hydrolysis were not different from the Km values, and these experiments indicated competitive inhibition. Activities were purified 126-fold by combined gel filtration and ion-exchange chromatography procedures with a yield of 63%. The purified enzyme displayed specific activities of 580 and 335 mumol of Pi released/min per mg of protein for ATP and ADP hydrolysis respectively. The action of the purified enzyme on several phosphate esters indicates that Rhodnius apyrase is a non-specific nucleosidetriphosphate diphosphohydrolase.

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 Purification of rabbit bone inhibitor of collagenase

1981 ◽  
Vol 195 (1) ◽  
pp. 159-165 ◽  
Author(s):  
T E Cawston ◽  
W A Galloway ◽  
E Mercer ◽  
G Murphy ◽  
J J Reynolds
Keyword(s):  
Tissue Culture ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Serine Proteinases ◽  
Bacterial Collagenase ◽  
Rabbit Bone

1. Rabbit bones in tissue culture synthesize an inhibitor of collagenase during the first 4 days of culture. 2. The inhibitor was purified by a combination of gel filtration, concanavalin A--Sepharose chromatography, ion-exchange chromatography and zinc-chelate affinity chromatography. 3. The purified inhibitor migrated as a single band on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and had a mol.wt. of 28000. 4. The inhibitor blocked the activity of the metalloproteinases collagenase, gelatinase, neutral proteinase III (proteoglycanase), human leucocyte collagenase and gelatinase, but not thermolysin or bacterial collagenase. The serine proteinases plasmin and trypsin were not inhibited. 5. The inhibitor interacted with purified rabbit bone collagenase with 1:1 stoichiometry. 6. The inhibitory activity was lost after incubation for 1 h at 90 degrees C, after treatment with trypsin (250 micrograms/ml) at 37 degrees C for 30 min and after reduction and alkylation.

scholarly journals Purification and properties of l-mandelate dehydrogenase and comparison with other membrane-bound dehydrogenases from Acinetobacter calcoaceticus

1987 ◽  
Vol 248 (3) ◽  
pp. 871-876 ◽  
Author(s):  
M E Hoey ◽  
N Allison ◽  
A J Scott ◽  
C A Fewson
Keyword(s):  
Lactate Dehydrogenase ◽  
Ion Exchange ◽  
Gel Filtration ◽  
Acinetobacter Calcoaceticus ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Ph Optimum ◽  
Purification And Properties ◽  
Potential Inhibitors ◽  
Triton X

L-Mandelate dehydrogenase was purified from Acinetobacter calcoaceticus by Triton X-100 extraction from a ‘wall + membrane’ fraction, ion-exchange chromatography on DEAE-Sephacel, (NH4)2SO4 fractionation and gel filtration followed by further ion-exchange chromatography. The purified enzyme was partially characterized with respect to its subunit Mr (44,000), pH optimum (7.5), pI value (4.2), substrate specificity and susceptibility to various potential inhibitors including thiol-blocking reagents. FMN was identified as the non-covalently bound cofactor. The properties of L-mandelate dehydrogenase are compared with those of D-mandelate dehydrogenase, D-lactate dehydrogenase and L-lactate dehydrogenase from A. calcoaceticus.

scholarly journals Dephosphorylation of Phytate by Using theAspergillus niger Phytase with a High Affinity for Phytate

1999 ◽  
Vol 65 (10) ◽  
pp. 4682-4684 ◽  
Author(s):  
Tadashi Nagashima ◽  
Tatsuya Tange ◽  
Hideharu Anazawa
Keyword(s):  
Phytic Acid ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Aspergillus Ficuum ◽  
Michaelis Constant ◽  
High Affinity ◽  
Significant Difference

ABSTRACT A phytase (EC 3.1.3.8 ) with a high affinity for phytic acid was found in Aspergillus niger SK-57 and purified to homogeneity in four steps by using ion-exchange chromatography (two types), gel filtration, and chromatofocusing. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified enzyme gave a single stained band at a molecular mass of approximately 60 kDa. The Michaelis constant of the enzyme for phytic acid (18.7 ± 4.6 μM) was statistically analyzed. In regard to the orthophosphate released from phytic acid, a significant difference between a lowKm phytase from A. niger SK-57 and a high Km phytase from Aspergillus ficuum was recognized.

Purification, characterization, and antifungal activity of chitinase from Fusarium chlamydosporum, a mycoparasiteto groundnut rust, Puccinia arachidis

1998 ◽  
Vol 44 (7) ◽  
pp. 646-651 ◽  
Author(s):  
N Mathivanan ◽  
V Kabilan ◽  
K Murugesan
Keyword(s):  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Puccinia Arachidis ◽  
Fusarium Chlamydosporum ◽  
Groundnut Rust ◽  
Germ Tubes

Chitinase (EC 3.2.1.14) was isolated from the culture filtrate of Fusarium chlamydosporum and purified by ion-exchange chromatography and gel filtration. The molecular mass of purified chitinase was 40 kDa as estimated by sodium dodecyl sulfate – polyacrylamide gel electrophoresis. Chitinase was optimally active at a pH of 5 and stable from pH 4 to 6 and up to 40°C. Among the metals and inhibitors tested, mercuric chloride completely inhibited the enzyme activity. The activity of chitinase was high on colloidal and pure chitin. The purified chitinase inhibited the germination of uredospores of Puccinia arachidis and also lysed the walls of uredospores and germ tubes. The results from these experiments indicated that chitinase of F. chlamydosporum plays an important role in the biocontrol of groundnut rust. Key words: Fusarium chlamydosporum, chitinase, purification, Puccinia arachidis, uredospores.

scholarly journals Multiple enzyme purifications from muscle extracts by using affinity-elution-chromatographic procedures

1977 ◽  
Vol 161 (2) ◽  
pp. 265-277 ◽  
Author(s):  
R K Scopes
Keyword(s):  
Gel Filtration ◽  
Phosphoglycerate Kinase ◽  
Gradient Elution ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Rabbit Muscle ◽  
Chromatographic Techniques ◽  
Ph Values ◽  
Chicken Muscle ◽  
Specific Activities

1. Starting with (NH4)2SO4 fractions of muscle extracts, procedures for purifying four to six separate enzymes from each fraction by using affinity-elution-chromatographic techniques are described. 2. Schemes for purifying 12 separate enzymes from rabbit muscle, and eight from chicken muscle extracts, are included. In nearly all cases the overall procedure involves three steps: the initial (NH4)2SO4 fractionation, the ion-exchange chromatography with affinity elution of the enzyme, and gel filtration. The specific activities of the enzymes so purified are comparable with the highest values in the literature. 3. The five schemes described include illustrations of affinity elution of the separate enzymes at different pH values, at different ionic strengths and in combination with conventional gradient elution. They also include stepwise adsorption on columns at different pH values. 4. Separation of two electrophoretically differing forms of phosphoglycerate kinase was achieved by gradient affinity elution from CM-cellulose. The lower-pI form was eluted by a lower concentration of substrate than the higher-pI form.

scholarly journals Cathepsin D. Purification of isoenzymes from human and chicken liver

1970 ◽  
Vol 117 (3) ◽  
pp. 601-607 ◽  
Author(s):  
A. J. Barrett
Keyword(s):  
Isoelectric Focusing ◽  
Cathepsin D ◽  
Ph Dependence ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Ph Optimum ◽  
Specific Activities ◽  
Acetone Fractionation ◽  
High Degree

1. The Barrett (1967) assay for cathepsin D was slightly modified. 2. The enzyme was purified from liver of man and chicken by a procedure involving autolysis, acetone fractionation, ion-exchange chromatography and isoelectric focusing. 3. Several isoenzymes of cathepsin D were resolved in the isoelectric-focusing step, and three major forms, α,β and γ, were distinguished for each species. 4. A modified analytical method of isoelectric focusing in polyacrylamide gel indicated a high degree of homogeneity of the purified β and γ isoenzymes from each species, and this was supported by their constant high specific activities. 5. Gel filtration of the isoenzymes in a calibrated column of Sephadex G-100 showed that each had a molecular weight of 45000. 6. Human cathepsin D had a pH optimum of 3.5, and that of chicken enzyme was 3.0, haemoglobin being used as substrate. In each species, the three isoenzymes have the same pH-dependence curve. 7. The purified cathepsin D samples showed very little action on acid-denatured albumin.

Caractéristiques fonctionnelles des activités peroxydasiques des feuilles et cals d'une plante à métabolisme acide crassulacéen, Pedilanthus tithymaloides variegatus, Euphorbiaceae

1984 ◽  
Vol 62 (9) ◽  
pp. 901-907 ◽  
Author(s):  
Pierre Bricage
Keyword(s):  
Ion Exchange ◽  
Physicochemical Properties ◽  
Affinity Chromatography ◽  
Enzyme Activities ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Leaf Tissues ◽  
Specific Activities ◽  
Isoenzyme Patterns

Peroxidases (donor:hydrogen-peroxide oxidoreductase; EC 1.11.1.7) from leaf tissues and calli were extracted and compared in terms of their specific activities at different pH and temperatures, their isoenzyme patterns and physicochemical properties. Three groups of enzyme activities were detected and their purification was performed by conventional methods (ammonium sulfate fractionation, ion-exchange chromatography, gel filtration, affinity chromatography).

Nutrition during mid to late pregnancy does not affect the birthweight response to mid pregnancy shearing

2002 ◽  
Vol 53 (1) ◽  
pp. 13 ◽  
Author(s):  
P. R. Kenyon ◽  
S. T. Morris ◽  
D. K. Revell ◽  
S. N. McCutcheon
Keyword(s):  
External Surface ◽  
Gel Filtration ◽  
Posterior Part ◽  
Late Pregnancy ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Male Gametes ◽  
Biochemical Fractionation ◽  
Viable Sperm ◽  
Triton X

This study was designed to determine whether dam nutrition during mid to latepregnancy influences birthweight responses from pregnancy shearing.Romney-cross ewes were either shorn during mid pregnancy(n = 68) or left unshorn (n= 66). Ewes were offered either a maintenance level of feed (a level ofnutrition that enabled the dam to maintain conceptus-free liveweight) or aed to apparenthomogeneity by using various biochemical fractionation procedures, such assolubilization with Triton X-100, sephadex gel filtration chromatography,concanavalin A–sepharose affinity chromatography anddiethylaminoethyl–cellulose ion-exchange chromatography. The isolatedPPase has a molecular mass of approximately 36 kDa and an isoelectric point of5.95. Sperm surface topography of the enzyme was investigated usingfluorescein isothiocyanate-conjugated antibody of the purified PPase. Theimmunofluorescent studies have demonstrated that the isolated PPase islocalized on the external surface of viable sperm. Immunocytochemical studiesalso revealed a marked topographical alteration of ecto-PPase duringepididymal transit of the male gametes. Immunoreactivity was observed all overthe surface of caput sperm, but was restricted primarily to the anterior tipof the head in the corpus sperm and to the posterior part of the head in caudasperm cells. The maturation-dependent decrease in PPase activity was alsoconfi

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