Purification of human plasma lecithin:cholesterol acyltransferase and its activation by metal ions

1980 ◽  
Vol 58 (7) ◽  
pp. 539-541 ◽  
Author(s):  
Ginzaburo Suzue ◽  
Camilla Vézina ◽  
Yves L. Marcel
Keyword(s):  
Human Plasma ◽  
Gel Electrophoresis ◽  
Wheat Germ ◽  
Polyacrylamide Gel Electrophoresis ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Lecithin:Cholesterol Acyltransferase ◽  
Preparative Electrophoresis ◽  
Preparative Ultracentrifugation ◽  
Apo Ai

Lecithin:cholesterol acyltransferase (LCAT) has been purified from human plasma by sequential preparative ultracentrifugation, ion-exchange chromatography on DEAE-Sephacel, and affinity chromatography on HDL-Sepharose and on wheat germ agglutinin-Sepharose. After the final step, which included preparative electrophoresis or alternatively, chromatography on hydroxylapatite, a purification of about 24 000-fold was obtained. The LCAT preparation was pure according to alkaline polyacrylamide and SDS–polyacrylamide gel electrophoresis and did not react against antisera to apo AI, AII, and D. The LCAT preparation obtained by preparative electrophoresis was stimulated by Cu2+, Ni2+, Co2+, and Zn2+ at both stages of the reaction, phospholipase reaction and cholesterol esterification. This stimulatory effect was abolished by EDTA.

Rapid separation of bovine caseins by mass ion exchange chromatography

1989 ◽  
Vol 56 (3) ◽  
pp. 391-397 ◽  
Author(s):  
K. F. Ng-Kwai-Hang ◽  
J. P. Pélissier
Keyword(s):  
Liquid Chromatography ◽  
Ion Exchange ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Polyacrylamide Gel ◽  
Rapid Separation ◽  
Rapid Isolation ◽  
Time Required

SummaryThe rapid isolation of major bovine caseins in gram quantities was investigated. Whole casein was precipitated from individual cow's milk by adjusting the pH to 4·6 and the precipitated casein was suspended in 4·5 M urea (pH 8·0) containing 0·02 M imidazole and 0·03 M β-mercaptoethanol, and bound on a QAE Zeta Prep 250 cartridge. Stepwise elution with the urea/imidazole β-mercaptoethanol buffer and varying amounts of NaCl gave five well resolved peaks, which were identified by polyacrylamide gel electrophoresis and fast protein liquid chromatography to be pure γ-casein, κ-casein. β-casein, β-casein and αs-casein, respectively. The ion exchange cartridge was regenerated by flushing with buffer containing 0·50 Μ-NaCl followed by equilibration with starting buffer before separation of next sample. The time required to run each sample including cartridge regeneration and equilibration was 4 hours.

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.

Charge Properties of Mitochondrial Matrix Proteins

1975 ◽  
Vol 53 (11) ◽  
pp. 1150-1157 ◽  
Author(s):  
P. M. Strasberg ◽  
K. B. Freeman
Keyword(s):  
Gel Electrophoresis ◽  
Matrix Protein ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Matrix Proteins ◽  
Mitochondrial Matrix ◽  
Total Fraction ◽  
Acidic Nature

Proteins of the rat liver mitochondrial matrix have been separated into anionic (acidic), cationic (basic), and neutral groups by electrophoresis. These groups represent 69, 8, and 23% of the total matrix protein, respectively, compared to 69, 21, and 10% for the cytosol protein. The acidic nature of the mitochondrial matrix proteins has been confirmed by cellulose ion-exchange chromatography, isoelectric focusing in sucrose gradients, and amino acid analysis. The anionic, cationic, and neutral matrix proteins were separated by sodium dodecyl sulfate – polyacrylamide gel electrophoresis into 18, 6, and 5 bands, respectively, compared to 22 bands for the total fraction. The significance of the charge properties of these proteins in terms of mitochondrial biogenesis is discussed.

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.

Biosynthèse "In Vitro" de l'Hormone Béta-Lipotropique de Boeuf

1974 ◽  
Vol 52 (5) ◽  
pp. 349-358 ◽  
Author(s):  
X. Bertagna ◽  
M. Lis ◽  
C. Gilardeau ◽  
M. Chrétien
Keyword(s):  
Amino Acids ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Usual Method ◽  
Pituitary Hormone ◽  
Melanocyte Stimulating Hormone

Sheep beta-lipotropic hormone (β-LPH) is a pituitary hormone made of 90 amino acids and having a portion of its sequence (41–58) identical with the structure of beta-melanocyte-stimulating hormone (β-MSH). We hypothetized that β-LPH could be the biological precursor of β-MSH. We studied the biosynthesis of these two molecules by monitoring the incorporation of radioactive amino acids in beef pituitary slices. We separated β-LPH from the other radioactive proteins with the usual method of purification described previously and we characterized the proteins by ion-exchange chromatography, gel filtration, and polyacrylamide gel electrophoresis. Our results show that the pituitary slices synthesized a radioactive β-LPH which has all the characteristics of non-radioactive β-LPH. However, in the conditions used, we could not demonstrate any biosynthesis of β-MSH after 4 h incubation. These results suggest that the conversion of β-LPH into β-MSH, if it exists, is a slow process and should be studied in more prolonged incubations.

scholarly journals A cystatin-like cysteine proteinase inhibitor from venom of the African puff adder (Bitis arietans)

1987 ◽  
Vol 246 (3) ◽  
pp. 795-797 ◽  
Author(s):  
H J Evans ◽  
A J Barrett
Keyword(s):  
Gel Electrophoresis ◽  
Cathepsin B ◽  
Proteinase Inhibitor ◽  
Cysteine Proteinase ◽  
Polyacrylamide Gel Electrophoresis ◽  
Minor Component ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Cysteine Proteinase Inhibitor ◽  
Strong Activity

Venoms from eight snakes have been screened for inhibitory activity against papain, strong activity being found in that of the African puff adder, Bitis arietans. The inhibitor from B. arietans venom has been purified by affinity chromatography on carboxymethyl-papain-Sepharose and ion-exchange chromatography. The inhibitor had an apparent Mr of 13,000 in SDS/polyacrylamide gel electrophoresis, and pI value of 6.5 (major component) or 6.3 (minor component). Values of Ki for the inhibition of papain, cathepsin B and dipeptidyl peptidase I were 0.10, 2.7 and 0.23 nM, respectively; chicken calpain was not inhibited.

scholarly journals A cyclic AMP-independent protein kinase from Candida albicans

1986 ◽  
Vol 234 (3) ◽  
pp. 543-546 ◽  
Author(s):  
B Gupta Roy ◽  
A Datta
Keyword(s):  
Candida Albicans ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Gel Electrophoresis ◽  
Thermal Denaturation ◽  
Polyacrylamide Gel Electrophoresis ◽  
Maximal Activity ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Independent Protein

A cyclic AMP-independent protein kinase which phosphorylates casein was purified to homogeneity from Candida albicans by affinity and ion-exchange chromatography. This protein kinase exhibits maximal activity with casein as substrate and is not stimulated by cyclic AMP or cyclic GMP. The Mr of the purified enzyme is 115,000, as determined by h.p.l.c. It migrates as a single band on gel electrophoresis and has three non-identical subunits, of Mr 44,000, 28,500 and 26,000, as determined by SDS/polyacrylamide-gel electrophoresis. This enzyme is insensitive to heparin, but is inhibited by polyamines. Furthermore, it is sensitive to thermal denaturation and to thiol reagents.

scholarly journals α-Lactalbumin and lactose concentrations in rat milk during lactation

1981 ◽  
Vol 194 (1) ◽  
pp. 149-154 ◽  
Author(s):  
K R Nicholas ◽  
P E Hartmann ◽  
B L McDonald
Keyword(s):  
Molecular Weight ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Significant Negative Correlation ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Biologically Active ◽  
Alpha Lactalbumin

Homogeneous rat alpha-lactalbumin was prepared from whey by chromatography on DEAE-Sephadex A-50 and Ultrogel AcA 44. Two biologically active forms of alpha-lactalbumin were apparent after ion-exchange chromatography, but on gel filtration the combined forms were eluted as a single peak with a molecular weight of approx. 33000. The molecular weight when determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis was 15100. Antiserum to alpha-lactalbumin was prepared from rabbits, and single radial immunodiffusion was used to measure the concentration of alpha-lactalbumin in milk expressed from rats during lactation and for 2 days after the cessation of lactation. A significant positive correlation (r = + 0.89) between the concentrations of alpha-lactalbumin and lactose was obtained for the first 20 days of lactation. This is consistent with the suggestion that alpha-lactalbumin may control the concentration of lactose in milk. However, a significant negative correlation (r = -0.91) between the concentration of alpha-lactalbumin and lactose was obtained for 2 days after the cessation of lactation on day 20.

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