scholarly journals Purification of the chloroplast-membrane dicyclohexylcarbodi-imide-binding proteolipid by ion-exchange chromatography

1979 ◽  
Vol 177 (2) ◽  
pp. 687-692 ◽  
Author(s):  
K Sigrist-Nelson ◽  
A Azzi
Keyword(s):  
Ion Exchange ◽  
Major Part ◽  
Membrane Lipids ◽  
Binding Protein ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Chloroplast Membranes ◽  
Rapid Procedure ◽  
Chloroplast Membrane ◽  
Endogenous Lipid

An efficient, mild and rapid procedure is reported for the separation of the dicyclohexyl-carbodi-imide-binding protein of chloroplast membranes from endogenous lipid components. By the use of ion-exchange chromatography the chloroplast proteolipid can be successfully separated from the major part of chlorophyll and other membrane lipids while being retained in a butan-1-ol milieu.

Inhibitors of Fibrinolysis in Amniotic Fluid

1980 ◽  
Vol 44 (01) ◽  
pp. 032-034 ◽  
Author(s):  
J E Walker ◽  
D M Campbell ◽  
D Ogston
Keyword(s):  
Ion Exchange ◽  
Amniotic Fluid ◽  
Inhibitory Activity ◽  
Major Part ◽  
Competitive Inhibition ◽  
Kinetic Studies ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Porcine Heart ◽  
Esterolytic Activity

SummaryAmniotic fluid inhibited the fibrinolytic, amidolytic and esterolytic activity of urokinase. Kinetic studies with AGLMe demonstrated non-competitive inhibition. A major part of the inhibitory activity could be separated from α1-antitrypsin by ion-exchange chromatography on DEAE-Sephadex A-50. Plasminogen activator prepared from porcine heart was not inhibited by amniotic fluid. Amniotic fluid also inhibited the caseinolytic and amidolytic activities of plasmin.

scholarly journals Insulin release and the microtubular system of the islets of Langerhans. Identification and characterization of tubulin-like protein

1975 ◽  
Vol 148 (2) ◽  
pp. 237-243 ◽  
Author(s):  
W Montague ◽  
S L Howell ◽  
I C Green
Keyword(s):  
Ion Exchange ◽  
Insulin Release ◽  
Islets Of Langerhans ◽  
Islet Cell ◽  
Time Course ◽  
Islet Cells ◽  
Binding Protein ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Supernatant Fraction

1. Incubation of islets of Langerhans in vitro in the presence of colchicine produced a progressive inhibition of the insulin-secretory response to glucose, which was dependent on the time of incubation. 2. The uptake of [3-H]colchicine by islet cells was a rapid process, equilibrium being reached in less than 30 min. Part of the colchicine taken up was bound to protein material, which was recovered largely in a post-microsomal supernatant fraction prepared from the islets. In contrast with this rapid uptake, the binding of colchicine by islet-cell proteins in intact islets or in islet homogenates was a slow process, and equilibrium was not reached for 60-90 min. After an initial 30 min delay, the time-course of the binding of [3-H]colchicine to islet-cell proteins paralleled that for the inhibitory effect of colchicine on insulin release. 3. Some purification of the colchicine-binding material present in islet homogenates could be achieved by precipitation of the protein with 2mM-CaCl2 (2.8-fold). However, ion-exchange chromatography on DEAE-Sephadex produced a further 27-fold purification on elution with 0.6M-NaCl. 4. Colchicine-binding protein prepared from islets by ion-exchange chromatography showed an intrinsic association constant for colchicine of 1.4muM and an apparent molecular weight on gel filtration of 110000. 5. These results suggest that colchicine-binding protein in islet cells closely resembles tubulin extracted from the other tissues. The delayed effectiveness of colchicine in inhibiting insulin secretion is not due to poor penetration of colchicine into the cells but rather to slow binding of the alkaloid to islet-cell tubulin. It seems likely that, as in other tissues, this binding prevents polymerization of the tubulin into microtubules, and thus interferes with the release process.

Studies on an Inhibitor of Plasminogen Activation in Human Serum

1973 ◽  
Vol 30 (02) ◽  
pp. 414-424 ◽  
Author(s):  
Ulla Hedner
Keyword(s):  
Ion Exchange ◽  
Human Serum ◽  
Antithrombin Iii ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Specific Adsorption ◽  
Partial Purification ◽  
Plasminogen Activation ◽  
Preparative Electrophoresis

SummaryA procedure is described for partial purification of an inhibitor of the activation of plasminogen by urokinase and streptokinase. The method involves specific adsorption of contammants, ion-exchange chromatography on DEAE-Sephadex, gel filtration on Sephadex G-200 and preparative electrophoresis. The inhibitor fraction contained no antiplasmin, no plasminogen, no α1-antitrypsin, no antithrombin-III and was shown not to be α2 M or inter-α-inhibitor. It contained traces of prothrombin and cerulo-plasmin. An antiserum against the inhibitor fraction capable of neutralising the inhibitor in serum was raised in rabbits.

Review on the Application of Mixed-mode Chromatography for Separation of Structure Isoforms

2018 ◽  
Vol 20 (1) ◽  
pp. 56-60 ◽  
Author(s):  
Tsutomu Arakawa
Keyword(s):  
Ion Exchange ◽  
Mixed Mode ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Charged State ◽  
Partial Structure ◽  
Reverse Phase ◽  
Oligomer Formation ◽  
Structure Rearrangement ◽  
Disulfide Scrambling

Proteins often generate structure isoforms naturally or artificially due to, for example, different glycosylation, disulfide scrambling, partial structure rearrangement, oligomer formation or chemical modification. The isoform formations are normally accompanied by alterations in charged state or hydrophobicity. Thus, isoforms can be fractionated by reverse-phase, hydrophobic interaction or ion exchange chromatography. We have applied mixed-mode chromatography for fractionation of isoforms for several model proteins and observed that cation exchange Capto MMC and anion exchange Capto adhere columns are effective in separating conformational isoforms and self-associated oligomers.

Sign in / Sign up

Export Citation Format

Share Document