scholarly journals CHARACTERIZATION OF ENZYMES HYDROLYZING ACYL NAPHTHYLAMIDES: II. TRIHALOGEN DERIVATIVES

1965 ◽  
Vol 13 (2) ◽  
pp. 117-124 ◽  
Author(s):  
V. K. HOPSU ◽  
R. S. SANTTI ◽  
G. G. GLENNER

Enzymes in guinea pig homogenates hydrolyzing a variety of halogenated and nonhalogenated acyl α- and β-naphthylamide substrates can be separated into two major groups on the basis of substrate hydrolysis rates, solubility and affector characteristics. Both groups of enzymes, those acting on the non-, mono- and dihalogenated acyl naphthylamides and those acting on trihalogen derivatives, have characteristics like those of arylesterases and are inseparable from enzymes hydrolyzing naphthol AS acetate. These enzymes are, However, separable on fractionation by starch gel electrophoresis and DEAE-cellulose chromatography from several enzymes catalyzing the hydrolysis of N-acyl amino acids (acylase I and II) and several amino acid β-naphthylamides. Species differences exist in the characteristics of enzymic hydrolysis of these acylarylamides.

1963 ◽  
Vol 41 (1) ◽  
pp. 671-696
Author(s):  
D. R. Whitaker ◽  
K. R. Hanson ◽  
P. K. Datta

Two methods are described for purification of the cellulase of Myrothecium verrucaria from concentrated culture filtrates. The steps of method I are (1) fractionation with ammonium sulphate, (2) elution through Sephadex G25, (3) elution through Sephadex G75, (4) precipitation with polymethacrylic acid, and (5) elution through Amberlite CG50 with citrate buffer containing a gradient of urea concentration. The steps of method II are precipitation by saturated ammonium sulphate, (2) and (4) as above, elution through DEAE-cellulose with phosphate buffer containing 7 M urea, followed by (2) and (3) as above. The two methods gave final products with identical specific activities toward carboxymethyl cellulose; the increase in specific activity was approximately 12-fold. Starch-gel electrophoresis at pH 6.8 showed no major indications of heterogeneity. The purified enzyme was unstable but could be stored frozen in dilute salt solution.Enzyme passed through DEAE-cellulose without an inhibitor of cellulase activity was contaminated by DEAE-substituted oligoglucosides and subject to proteolysis. Urea could be replaced by cellobiose as an inhibitor but the latter gave enzyme contaminated by products of transfer reactions.Binding of urea by the resin is shown to influence significantly the resolution attainable in chromatographic fractionations on Amberlite CG-50 with buffers containing gradients of urea concentration.Procedures for dialysis and desalting of cellulases and a compact reaction vessel for pH stats are described.


1963 ◽  
Vol 41 (3) ◽  
pp. 671-696 ◽  
Author(s):  
D. R. Whitaker ◽  
K. R. Hanson ◽  
P. K. Datta

Two methods are described for purification of the cellulase of Myrothecium verrucaria from concentrated culture filtrates. The steps of method I are (1) fractionation with ammonium sulphate, (2) elution through Sephadex G25, (3) elution through Sephadex G75, (4) precipitation with polymethacrylic acid, and (5) elution through Amberlite CG50 with citrate buffer containing a gradient of urea concentration. The steps of method II are precipitation by saturated ammonium sulphate, (2) and (4) as above, elution through DEAE-cellulose with phosphate buffer containing 7 M urea, followed by (2) and (3) as above. The two methods gave final products with identical specific activities toward carboxymethyl cellulose; the increase in specific activity was approximately 12-fold. Starch-gel electrophoresis at pH 6.8 showed no major indications of heterogeneity. The purified enzyme was unstable but could be stored frozen in dilute salt solution.Enzyme passed through DEAE-cellulose without an inhibitor of cellulase activity was contaminated by DEAE-substituted oligoglucosides and subject to proteolysis. Urea could be replaced by cellobiose as an inhibitor but the latter gave enzyme contaminated by products of transfer reactions.Binding of urea by the resin is shown to influence significantly the resolution attainable in chromatographic fractionations on Amberlite CG-50 with buffers containing gradients of urea concentration.Procedures for dialysis and desalting of cellulases and a compact reaction vessel for pH stats are described.


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.


2014 ◽  
Vol 30 (3) ◽  
pp. 377-390 ◽  
Author(s):  
S.S.A. Egena ◽  
R.O. Alao

Biochemical diversity or polymorphism is the occurrence of varieties attributed to biochemical differences which are under genetic control. It has created a leeway for the genetic improvement of farm animals. This is because it can be used as a useful tool for the characterization of livestock breeds and population. This way, the degree of similarity or differences within and between breeds can be ascertained and this differences or similarity are important raw materials for genetic improvement of animals. Data obtained on gene frequencies and genotypes through polymorphism study makes it not only possible to compare the gene stocks of animals, the possible effects of the genes on reproductive and performance traits, but also study genetic variability under different environmental conditions of selection. This study was carried out to review haemoglobin (Hb) polymorphism in selected farm animals with the view of finding out the type of polymorphism observed by starch gel electrophoresis due to variation in the amino acid sequence in the polypeptide chains of Hb. The review showed clearly that there is a gene-controlled diversity in the different farm animals considered. This could serve as a reference point for future studies earmarked for the improvement of the animals possibly via marker-assisted selection.


1986 ◽  
Vol 32 (6) ◽  
pp. 481-486 ◽  
Author(s):  
C. Osothsilp ◽  
R. E. Subden

To obtain NAD-dependent malic enzyme mutants of Schizosaccharomyces pombe, a colony color indicator screening system was developed. Mutants defective for malic acid utilization (mau mutants) are yellow, while wild-type colonies are blue on the defined bromcresol green based indicator medium. NAD-dependent malic enzyme mutants were distinguished from other mau mutants by subsequent, starch gel electrophoresis, spectrophotometry, complementation tests, and intermediate pool analysis with cell-free extracts.


1990 ◽  
Vol 269 (1) ◽  
pp. 13-18 ◽  
Author(s):  
Y Homma ◽  
Y Emori ◽  
F Shibasaki ◽  
K Suzuki ◽  
T Takenawa

A novel bovine spleen phosphoinositide-specific phospholipase C (PLC) has been identified with respect to immunoreactivity with four independent antibodies against each of the PLC isoenzymes, and purified to near homogeneity by sequential column chromatography. Spleen contains three of the isoenzymes: two different gamma-types [gamma 1 and gamma 2, originally named as PLC-gamma [Rhee, Suh, Ryu & Lee (1989) Science 244, 546-550] and PLC-IV [Emori, Homma, Sorimachi, Kawasaki, Nakanishi, Suzuki & Takenawa (1989) J. Biol. Chem. 264, 21885-21890] respectively] and delta-type of the enzyme, but PLC-gamma 1 is separated from the PLC-gamma 2 pool by the first DEAE-cellulose column chromatography. Subsequently, PLC-delta is dissociated on the third heparin-Sepharose column chromatography. The purified enzyme has a molecular mass of 145 kDa on SDS/polyacrylamide-gel electrophoresis and a specific activity of 12.8 mumol/min per mg with phosphatidylinositol 4,5-bisphosphate as substrate. This enzyme activity is dependent on Ca2+ for hydrolysis of all these phosphoinositides. None of the other phospholipids examined could be its substrate at any concentration of Ca2+. The optimal pH of the enzyme is slightly acidic (pH 5.0-6.5).


1967 ◽  
Vol 105 (3) ◽  
pp. 1307-1312 ◽  
Author(s):  
R. Helen Eaton ◽  
D W Moss

1. Purified human liver and small-intestinal alkaline orthophosphatases release inorganic phosphate at appreciable rates from a variety of organic pyrophosphate substrates. 2. The pyrophosphatase action is inhibited by Mg2+ ions at concentrations that activate the hydrolysis of orthophosphate substrates by these enzymes. 3. The results of mixed-substrate experiments, denaturation studies with heat or urea and starch-gel electrophoresis suggest that both orthophosphatase and pyrophosphatase activities are, in each preparation, properties of a single enzyme. 4. Intestinal phosphatase shows greater pyrophosphatase activity relative to orthophosphatase than the liver enzyme.


OENO One ◽  
1998 ◽  
Vol 32 (1) ◽  
pp. 17
Author(s):  
Ferjani Ben Abdallah ◽  
Farhat Chibani ◽  
Asma Fnayou ◽  
Abdelwahed Ghorbel ◽  
Jean-Michel Boursiquot

<p style="text-align: justify;">61 tunisian autochton grapevine varieties have been collected for biochemical identification. Isozymes analysis with starch gel electrophoresis technique was used to confirn or to cancel random denominations awarded to the majority of these local varieties. In our conditions, concentrated plant extracts were obtained from vigorous donnant canes newly cut off from selected mother plants during automn. These allowed us to dispose of rigorously interpretable isozyme banding patterns of GPI and PGM systems and to overcome difficulties often related to the use of PGM system. The study of GPII and PGM enzyme systems allowed us to classify the autochton accessions into 16 different groups from which 5 groups containing only 2 or 3 varieties.</p><p style="text-align: justify;">On the other hand, the study of AAT and peroxydase enzyme systems has shown stable and legible isozyme banding patterns allowing to discriminate between equivalent accessions such as Sakasly and Kahli (two black local vines very similar), 3 varieties of Bidh Hamem (Bidh Hamem, Bidh Hamem Rafraf and Bidh Hamem Sfax), and 2 varieties of Bezzoul Kelba Bidha (Sfax and Gabes). In addition, certain varieties having for longtime the same denominations were characterized. A case of point the 4 varieties Khalt meaning mixture (Bouchemma, Abiedh, Mdaouer and Souche 1) and the 3 varieties of Arich (Ahmar, Dressée, and Jerba) were proved to be completely different from each other. In the same way, Bezzoul Khadem has been differed from Hemri variety. The complementary use of berry colour allowed to discriminate between Saouadi, Khdhiri and Jebbi varieties and to subdivise the remainig groups into sub-groups.</p><p style="text-align: justify;">The study of GPI, PGM, AAT and peroxydase isozyme banding patterns in combination with berry colour has led to establish a classification of the 61 autochton varieties into 37 groups including 26 varieties definitely differentiated through the results of this biochemical study.</p>


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.


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