scholarly journals A chromatographic preparation of ox growth hormone

1966 ◽  
Vol 100 (3) ◽  
pp. 593-600 ◽  
Author(s):  
M Wallis ◽  
HBF Dixon

1. A method is described for the chromatographic preparation of ox growth hormone. It involves chromatography of an extract of anterior pituitary lobes on DEAE-cellulose, followed by rechromatography on a dextran gel of low cross-linkage (Sephadex G-100). 2. The product is highly active in growth-hormone assays, and is obtained in good yield. It was homogeneous by several criteria, but showed some heterogeneity on starch-gel electrophoresis. 3. The molecular weight of the hormone was estimated from its behaviour on gel-filtration columns under various conditions. Evidence that the hormone may dissociate into sub-units under some conditions is presented.

1977 ◽  
Vol 167 (3) ◽  
pp. 765-773 ◽  
Author(s):  
R J Pierce ◽  
R G Price

beta-D-Galactosidase and beta-D-glucosidase activities were determined in homogenates of marmoset kidney by using the appropriate 4-methylumbelliferyl glycoside, beta-D-Galactosidase activity was separated into two main components by ion-exchange chromatography on DEAE-cellulose, starch-gel electrophoresis, isoelectric focusing and gel filtration on Sephadex G-200. One form designated A had a pI of 5.1, was loosely bound to DEAE-cellulose at pH7.0, remained near the origin on starch-gel electrophoresis at pH 7.0 and had an apparent molecular weight of 160000. The second beta-D-galactosidase component, designated B, was associated with the total beta-D-glucosidase activity, had a pI of 4.3, was firmly bound to DEAE-cellulose, migrated rapidly towards the anode on starch-gel electrophoresis and had an apparent molecular weight of 50000. The optimum pH values of beta-D-galactosidase A and B were 4.5 and 6.0 respectively. beta-D-Galactosidase A was activated by 0.1 M-NaC1 but the activity of the B form was inhibited by 1 M-NaC1 at pH 4.5. beta-D-galactosidase had a bimodal distribution, the A form being recovered in the lysosomal fraction whereas the B form was present in the soluble fraction, as was the major portion of the beta-D-glucosidase activity. The lysosomal and soluble forms were further characterized by DEAE-cellulose chromatography.


1963 ◽  
Vol 26 (2) ◽  
pp. 259-263 ◽  
Author(s):  
A. L. C. WALLACE ◽  
K. A. FERGUSON

SUMMARY Growth hormone has been prepared from sheep pituitary glands by chromatography of a simple buffer extract on DEAE-cellulose. The preparation appears to be free of other anterior pituitary hormones but shows two main components when analysed by starch gel electrophoresis. These components appear similar to those present in standard preparations of ox growth hormone. Sheep growth hormone prepared by this method is not significantly less active than purified ox growth hormone when compared by the tibial-epiphysial cartilage response in hypophysectomized rats.


1965 ◽  
Vol 32 (3) ◽  
pp. 321-327 ◽  
Author(s):  
A. L. C. WALLACE ◽  
W. R. SOBEY

SUMMARY The NIH-B2-GH preparation of ox growth hormone (GH) was separated by chromatography on DEAE-cellulose into six fractions. Five of these fractions when assayed in hypophysectomized rats showed GH activity ranging in potency from 0·25 to 2·5 times the starting material. Growth activity could not be correlated with the concentration of any single component revealed by starch gel electrophoresis. Antisera produced to NIH-B2-GH had antihormone activity and produced two precipitin lines in Ouchterlony diffusion tests. One of these lines was associated with serum γ-globulin and was shared by all five fractions. The other line was present in only two of the fractions, and these contained the more anionic components. It is suggested that the more cationic growth-active components present in bovine and ovine GH preparations do not readily produce precipitating antibodies and that this may complicate the results of precipitin and gel diffusion tests when heterogeneous GH preparations have been used to prepare the antisera.


1972 ◽  
Vol 50 (1) ◽  
pp. 9-15 ◽  
Author(s):  
D. J. Ecobichon

The cytoplasmic carboxylesterases of bovine, ovine, equine and human liver were fractionated by starch gel electrophoresis and by gel filtration on Sephadex. While species-specific, heterogeneous bands were observed in starch gel, the esterases of the bovine, ovine and equine liver were eluted from Sephadex G-100 as single peaks of activity, each with a characteristic elution volume. Gel filtration of human liver extracts yielded two peaks of activity, one containing electrophoretically slow esterases, the other electrophoretically fast esterases. Extracted equine and human hepatic carboxylesterases aggregated readily on storage or concentration, forming larger units which could be dissociated by a combination of acidic pH and high salt concentration. Molecular weight estimates of the hepatic esterases by gel filtration on Sephadex G-100 and G-200 yielded values of 65 000 for ovine, 55 000 for bovine, 96 000 and 70 000 for equine variants and 180 000 and 65 000 for human variants. The observations suggested that the cytoplasmic enzymes in relatively crude hepatic extracts had a lower molecular weight than those in concentrated or partially purified preparations which formed stable dimers or trimers.


1966 ◽  
Vol 44 (4) ◽  
pp. 469-473 ◽  
Author(s):  
John Y. S. Chan ◽  
Edwin T. Mertz

Bovine and human plasminogen preparations were analyzed by starch-gel electrophoresis at pH 2.5 and 0.10 ionic strength. The bands were activated with urokinase and the proteolytic and esterolytic activities measured. Bovine euglobulin contains one plasminogen band, B-1. Plasminogen prepared from bovine euglobulin by continuous electrophoresis at pH 3.5 contains B-1 and a faster plasminogen band, B-2. B-1 and B-2 are also found in bovine plasminogen prepared by DEAE-cellulose chromatography. All three preparations on activation give the same two plasmin bands on starch gel. Human euglobulin also contains two active plasminogen bands H-1 and H-2. Plasminogen prepared from human euglobulin by continuous electrophoresis at pH 3.5 contains H-1, H-2, and a faster minor plasminogen band, H-3. All highly purified human plasminogens derived from Cohn fraction III contain either H-3 as a major band and an additional plasminogen band, H-4, or only H-3, but no H-1 and H-2. On activation with urokinase or streptokinase, human plasminogen preparations give one or two plasmin bands. It is concluded that bovine B-2 and human H-3 and H-4 are altered forms of euglobulin plasminogen created during isolation procedures. Essentially pure human H-3 can be prepared by continuous electrophoresis from Cutter plasminogen.


1974 ◽  
Vol 41 (2) ◽  
pp. 269-282 ◽  
Author(s):  
Margaret L. Green ◽  
P. M. D. Foster

SummaryThe rates of proteolysis during ripening were followed in cheeses made with either calf rennet or swine pepsin and either starter or δ-gluconic acid lactone (GAL) as a replacement for the starter. A gel-filtration column technique and starch-gel electrophoresis were used for analysis, and bacterial counts were made on all samples. Proteolysis was faster in cheeses made using GAL than in those made using starter and also slightly faster in GAL cheeses made with swine pepsin than in those made with rennet. Further, it was considerably slower in starter-containing cheeses made with swine pepsin than in those made with rennet. It is suggested that these differences were due to the much greater rate of development of acidity in cheeses made with GAL than in those made with starter, which resulted in more of the coagulant being incorporated into the curd in an active state. The rate of proteolysis in starter-containing cheeses appeared to follow a characteristic course, being initially slow, then markedly increasing with a later slow decline. It is suggested that the increase in the rate of proteolysis was due to an increase in the total activity of bacterial proteinases released by lysis of the bacteria. Indications were obtained that the coagulants and bacterial proteinases catalysed broadly similar patterns of protein breakdown in cheese, and that medium-sized peptides (mol. wt 9000–14000) were formed as definite intermediates in the process. The results also showed that rennet and swine pepsin remained active for at least 7 months in GAL cheeses, that rennet contributed significantly to proteolysis in starter-containing cheeses, and that swine pepsin was at least extensively inactivated and possibly completely inactivated during cheese-making with starter.


The enzyme benzylamine oxidase of pig plasma has been purified and some of the properties of the pure preparation have been studied. The purification procedure included several precipitations with ammonium sulphate and separations of proteins by column chromatography, first on DEAE-cellulose, followed by DEAE-Sephadex and lastly on a hydroxyapatite column. Crystals were prepared from solutions of the purified enzyme by adding ammonium sulphate. The crystalline preparation was homogeneous when studied by starch-gel electrophoresis and by ultracentrifugation. The molecular weight, as determined on the analytical ultracentrifuge, was 195 000. The copper content of the enzyme, as determined by radioactivation analysis, was about four atoms of Cu per molecule of enzyme. Concentrated solutions of the enzyme had a pink colour; the colour disappeared when substrate (benzylamine) was added under anaerobic conditions. The amines which were tested and found to be oxidized by the pure enzyme were: benzylamine, histamine, mescaline and 4-picolylamine. The affinity of the enzyme for benzylamine was more than one hundred times that for histamine.


1964 ◽  
Vol 42 (6) ◽  
pp. 841-849 ◽  
Author(s):  
W. H. McShan ◽  
B. B. Saxena ◽  
R. O. Creek

The results of this study indicate that highly purified follicle-stimulating hormone (FSH) was prepared from human anterior pituitary glands by ammonium sulphate (AS) fractionation, zone electrophoresis, and starch gel electrophoresis. The activity of this preparation was approximately 14.7 times that of the sheep pituitary FSH standard. The fractions from zone and starch gel electrophoresis with which luteinizing hormone (LH) was associated also contained thyrotropic hormone (TSH). There was little decrease in the gonadotropic activity of human anterior pituitary glands recovered at different times up to 24 hours post-mortem.


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