Muscle Arylamidase Activity of Several Marine Species

1974 ◽  
Vol 31 (4) ◽  
pp. 445-449
Author(s):  
Beverly A. Bauer ◽  
R. R. Eitenmiller
Keyword(s):  
Blue Crab ◽  
Gel Electrophoresis ◽  
Marine Species ◽  
Maximum Activity ◽  
Crude Extracts ◽  
Muscle Extract ◽  
Optimum Ph

Arylamidase activity in muscle extracts of mackerel, mullet, whiting, blue crab, quahog clam, and shrimp was investigated. The optimum pH for activity was between 7.0 and 7.5 for each species using alanyl-β-naphthylamide as substrate. Enzymes of the three species of fish exhibited maximum activity against alanyl-β-naphthylamide, whereas the clam showed maximum activity with leucyl-β-naphthylamide and the crab and shrimp with lysyl-β-naphthylamide. Puromycin inhibited each of the arylamidases. Acrylamide gel electrophoresis of the crude extracts suggested the presence of one arylamidase in muscle of the fish, crab, and clam. The shrimp muscle extract contained two active enzymes. Upon electrophoresis, the faster moving enzyme from shrimp muscle was active against lysyl-, alanyl-, and leucyl-β-naphthylamides, but the slower moving enzyme was active only against lysyl-β-naphthylamide.

scholarly journals Characterization and Effects of β–Galactosidase in the Crude Extracts of Cuminum cyminum and Curcuma longa in Preparation of Delactosed Milk and Whey

2016 ◽  
Vol 5 (1) ◽  
pp. 1
Author(s):  
Omar M. Atrooz
Keyword(s):  
Enzyme Activity ◽  
Curcuma Longa ◽  
Maximum Activity ◽  
Cow’S Milk ◽  
Enzyme Kinetic ◽  
Optimum Temperature ◽  
Cuminum Cyminum ◽  
Crude Extracts ◽  
Optimum Ph ◽  
Hydrolysis Of

<p>β-galactosidase (EC 3.2.1.23) was extracted from <em>Cuminum cyminum </em>and<em> Curcuma longa</em>. The crude extracts of these plants were then characterized in term of pH, temperature, and enzyme kinetic. The crude extracts were also used in hydrolysis of lactose in milk and whey. The enzyme activity was measured by its ability to hydrolyze the substrate o-nitrophenyl β -D-galactopyranoside (ONPG).</p><p>It was found that β-galactosidase in the crude extracts of <em>Cuminum cyminum </em>exhibited maximum activity at pH 8.0 and optimum temperature at 60 °C. While, β-galactosidase in the crude extracts of <em>Curcuma longa</em> have optimum pH at 5.0 and 7.0 and optimum temperature at 50 °C.The K<sub>m</sub> and V<sub>max</sub> values of the β-galactosidase in the crude extracts of <em>Cuminum cyminum</em> and <em>Curcuma longa </em>were 4.16 mM and 0.087 μmol/min, and 2.63 mM and 0.333μmol/min, respectively.</p><p>The results showed that 96.84-97.08% of lactose was hydrolyzed in cow’s milk and whey when treated with crude extracts of <em>Cuminum cyminum</em> and 90-98.6% when treated with crude extracts of <em>Curcuma longa</em>.</p>

Polygalacturonase isolated from the culture of the psychrophilic fungus Sclerotinia borealis

1997 ◽  
Vol 43 (5) ◽  
pp. 417-424 ◽  
Author(s):  
Toshihide Takasawa ◽  
Keiko Sagisaka ◽  
Koichi Yagi ◽  
Kyoko Uchiyama ◽  
Atsushi Aoki ◽  
...  
Keyword(s):  
Culture Medium ◽  
Enzyme Reaction ◽  
Wheat Seedling ◽  
Maximum Activity ◽  
Reducing Sugar ◽  
Pectic Acid ◽  
Snow Mold ◽  
Viscosity Change ◽  
Optimum Ph ◽  
Psychrophilic Fungus

A polygalacturonase was isolated from the culture medium of Sclerotinia borealis, a psychrophilic fungus that grows on lawn and wheat seedling under the snow in winter and induces the snow mold disease. Pectic acid was a better substrate of this enzyme than pectin when the activity was determined by measuring the reducing sugar produced. However, when the activity was measured by viscosity change, the viscosity of pectin decreased more rapidly than that of pectic acid. The results of viscosity change apparently indicate that the polygalacturonase catalyzes pectin hydrolysis as an endo-type enzyme. Highly methyl-esterified pectin was a poor substrate, as determined by measurements of reducing sugar production and viscosity change. It is suggested from the results that the methoxy group of pectin affects the polygalacturonase reaction. A reaction mechanism was proposed for the polygalacturonase reaction. Molecular mass of this enzyme was 40 kDa and its isoelectric point was pH 7.5. Optimum pH of the enzyme reaction was 4.5 and its optimum temperature was 40–50 °C. Thirty percent of the maximum activity was observed at 5 °C, but it was only slightly active above 60 °C. The activity was preserved for more than 2 years at 5 °C and pH 4.5, but it was lost when kept at room temperature overnight or heated at 50 °C for 30 min. The amino acid sequence of the N-terminal region of the psychrophilic polygalacturonase of Sclerotinia borealis is compared with those of polygalacturonases of mesophilic fungi. The function of this enzyme against the target plants is discussed with reference to the reaction of polygalacturonases of mesophilic fungi.Key words: polygalacturonase, pectin-hydrolyzing enzyme, psychrophilic fungi, snow mold disease, Sclerotinia borealis.

scholarly journals Purification and characterization of acid phosphatase from a germinating black gram (Vigna mungo L.) seedling

2011 ◽  
Vol 63 (3) ◽  
pp. 747-756 ◽  
Author(s):  
A.K.M. Asaduzzaman ◽  
Habibur Rahman ◽  
Tanzima Yeasmin
Keyword(s):  
Acid Phosphatase ◽  
Gel Electrophoresis ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Inhibitory Effect ◽  
Maximum Activity ◽  
Exchange Chromatography ◽  
Black Gram ◽  
Km Value

An acid phosphatase has been isolated and purified from an extract of a germinating black gram seedling. The method was accomplished by gel filtration of a germinating black gram seedling crude extract on sephadex G-75 followed by ion exchange chromatography on DEAE cellulose. The acid phosphatase gave a single band on SDS-polyacrylamide slab gel electrophoresis. The molecular weight of the acid phosphatase determined by SDS-polyacrylamide slab gel electrophoresis was estimated to be 25 kDa. The purified enzyme showed maximum activity at pH 5 and at temperature of 55?C. Mg2+, Zn2+ and EDTA had an inhibitory effect on the activity of the acid phosphatase. Black gram seedling acid phosphatase was activated by K+, Cu2+ and Ba2+. The Km value of the enzyme was found to be 0.49 mM for pNPP as substrate.

scholarly journals Production of glucose and fructose syrups from cassava (Manihot esculenta Crantz) starch using enzymes produced by microorganisms isolated from Brazilian Cerrado soil

2010 ◽  
Vol 30 (1) ◽  
pp. 213-217 ◽  
Author(s):  
Roberto do Nascimento Silva ◽  
Fábio Pereira Quintino ◽  
Valdirene Neves Monteiro ◽  
Eduardo Ramirez Asquieri
Keyword(s):  
Aspergillus Niger ◽  
Manihot Esculenta ◽  
Glucose Isomerase ◽  
Cassava Starch ◽  
Maximum Activity ◽  
Brazilian Cerrado ◽  
Initial Activity ◽  
Manihot Esculenta Crantz ◽  
Streptomyces Sp ◽  
Optimum Ph

The high demands for sugars and the development of enzymatic technology have increased the production of sweeteners, especially for glucose and fructose syrups. This work describe a technology for glucose and fructose syrups from Brazilian cassava starch using enzymes produced by soil microrganisms isolated from the Brazilian Cerrado soil. Firstly, Aspergillus niger and Streptomyces sp. were isolated from the soil and used as glucoamylase (GA) and glucose isomerase (GI) producer sources. After characterization, GA and GI exhibited optimum pH 4.5 and 8.0, respectively. GA showed maximum activity at 60 ºC and GI at 85 ºC. GA and GI retained 65 and 80%, respectively, of initial activity after 180 minutes of incubation at 60 ºC. The kinetic parameters Km and Vmáx were 0.476 (mg.mL-1) and 8.58 (µmol/minute) for GA and 0.082 (M) and 48.20 (µmol/minute) for GI. The maximum glucose syrups production occurred after 24 hours of reaction with a 98% yield. The production of fructose syrups with 42% (w/v) was reached after 96 hours of reaction.

Pyrimidine reducing enzymes of rat liver

1976 ◽  
Vol 54 (2) ◽  
pp. 178-184 ◽  
Author(s):  
Ronald O. Hallock ◽  
Esther W. Yamada
Keyword(s):  
Carbon Dioxide ◽  
Rat Liver ◽  
Gel Electrophoresis ◽  
Marker Enzyme ◽  
Good Separation ◽  
Cytosol Fraction ◽  
Radioactive Carbon ◽  
Mitochondrial Fractions ◽  
Optimum Ph ◽  
Rat Liver Cells

Dihydrouracil dehydrogenase (NADP+) (EC 1.3.1.2) was partially purified from the cytosol fraction of rat liver and fractionated by disc gel electrophoresis. A major and minor band were visualized by staining for enzyme activity. The substrate specificity of these bands was investigated. It was found that both bands were two to three times more active with dihydrothymine as substrate than with dihydrouracil in the presence of NADP+ and the optimum pH of 7.4.Mitochondrial fractions containing most of the NADH-dependent uracil reductase of rat liver cells were fractionated by centrifugation in sucrose density gradients. Two procedures involving linear or discontinuous gradients were used. By both, good separation of NADH- and NADPH-dependent reductases was achieved. Marker enzyme studies supported the view that the NADH-dependent enzyme is located principally in mitochondria whereas the NADPH-dependent enzyme is mainly in plasma and endoplasmic reticulum membranes. For the NADH-dependent reductase the apparent Km for thymine at pH 7.4 was 1.39 times that found for uracil whereas for the NADPH-dependent enzyme the apparent Km values were similar for the two substrates at this pH.Dihydrouracil was the principal product isolated by paper chromatography from the reaction mixture containing a partially purified fraction of mitochondria, uracil and NADH at pH 7.4. This fraction also catalyzed the formation of radioactive carbon dioxide from [2-14C]uracil. The proportion of CO2 formed by the mitochondria was about 10% of that formed by the original homogenate.

scholarly journals Properties of pig synovial collagenase

1980 ◽  
Vol 189 (2) ◽  
pp. 349-357 ◽  
Author(s):  
J A Tyler ◽  
T E Cawston
Keyword(s):  
Isoelectric Focusing ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Active Form ◽  
Sodium Dodecyl ◽  
Type Ii ◽  
Polyacrylamide Gels ◽  
Optimum Ph ◽  
Detectable Difference

1. Properties of a purified chemically activated form of pig synovial collagenase were examined and compared with a spontaneously active form of the enzyme. 2. The active enzyme has a specific activity of 53 000 units (microgram/min)/mg, a mol.wt. of 44 000 (by sodium dodecyl sulphate/polyarcylamide-gel electrophoresis in 2-mercaptoethanol) and pI 5.2 (by isoelectric focusing in polyacrylamide gels). 3. The activity has the characteristics of a metalloproteinase that degrades types I and III soluble or insoluble collagens in preference to type II, at an optimum pH of 6.5-8.5. 4. There is no detectable difference in these properties between the chemically activated and spontaneously active form of collagenase.

scholarly journals Purification of 2-oxoaldehyde dehydrogenase and its dependence on unusual amines

1975 ◽  
Vol 149 (3) ◽  
pp. 609-617 ◽  
Author(s):  
J Dunkerton ◽  
S P James
Keyword(s):  
Enzyme Activity ◽  
Gel Electrophoresis ◽  
General Structure ◽  
Polyacrylamide Gel Electrophoresis ◽  
Maximum Activity ◽  
Polyacrylamide Gel ◽  
Ph Optimum ◽  
Ph Values ◽  
Sheep Liver ◽  
Living Tissues

1. 2-Oxoaldehyde dehydrogenase was purified from sheep liver and gave one band on polyacrylamide-gel electrophoresis. 2. The enzyme was completely dependent for its activity on the presence of Tris or one of a number of related amines, all of general structure: (See article). When more than one R group was hydrogen no enzyme activity was observed. 3. Only one of these amines is known to exist in living tissues and large concentrations of all amines were required for maximum activity. L-2-Aminopropan-1-ol was the most effective amine on the basis of substrate Km and Vmax. values and the amine Km values. 4. The enzyme was activated by phosphate which lowered the Km values for methylglyoxal, amine and NAD+. 5. The pH optimum of the enzyme was 9.3 and there was no activity at pH values below 7.8. A search for activators that might produce activity at pH 7.4 proved unsuccessful. 6. The enzyme was inhibited by rather large concentrations of barbiturates (6-46 mM) and nitro-alcohol analogues of the activating amines (66-139 mM).

Glycosidases in bovine milk: α-mannosidase and its inhibition by zwitterions

1968 ◽  
Vol 46 (11) ◽  
pp. 1351-1356 ◽  
Author(s):  
A. Mellors ◽  
V. R. Harwalkar
Keyword(s):  
Amino Acid ◽  
Polyacrylamide Gel Electrophoresis ◽  
Bovine Milk ◽  
Maximum Activity ◽  
Manganese Ions ◽  
Ammonium Sulfate Precipitation ◽  
Optimum Ph ◽  
High Concentrations ◽  
Hydrolysis Of ◽  
Dibasic Amino Acids

α-Mannosidase is present in bovine milk and is associated with the β-casein fraction following polyacrylamide gel electrophoresis. It was separated from the casein complex by ammonium sulfate precipitation in the presence of 10% (v/v) ethanol. Zinc or manganese ions are required for maximum activity and the enzyme is very labile. The optimum pH for the hydrolysis of p-nitrophenyl α-mannoside is about 3. In the presence of amino acid buffers the enzyme is inhibited. For dibasic amino acids this inhibition is inversely related to the [Formula: see text] of the amino acid and is apparently due to inhibition by zwitterions. High concentrations of the substrate p-nitrophenyl α-mannoside are inhibitory, and the apparent Km for this hydrolysis is 1.2 mM.

scholarly journals Characterization of a Novel β-Xylosidase, XylC, fromThermoanaerobacterium saccharolyticumJW/SL-YS485

2010 ◽  
Vol 77 (3) ◽  
pp. 719-726 ◽  
Author(s):  
Weilan Shao ◽  
Yemin Xue ◽  
Ailian Wu ◽  
Irina Kataeva ◽  
Jianjun Pei ◽  
...  
Keyword(s):  
Gel Electrophoresis ◽  
Glycosyl Hydrolase ◽  
Gel Filtration ◽  
Industrial Applications ◽  
Maximum Activity ◽  
Site Directed Mutagenesis ◽  
Stem Loop ◽  
Translational Initiation ◽  
Reading Frame ◽  
Gradient Gel Electrophoresis

ABSTRACTThe 1,914-bp open reading frame ofxylCfromThermoanaerobacterium saccharolyticumJW/SL-YS485 encodes a calculated 73-kDa β-xylosidase, XylC, different from any glycosyl hydrolase in the database and representing a novel glycohydrolase family. Hydrolysis occurred under retention of the anomeric configuration, and transglycosylation occurred in the presence of alcohols as acceptors. With the use of vector pHsh, expression of XylC, the third β-xylosidase in this bacterium, increased approximately 4-fold when a loop within the translational initiation region in the mRNA was removed by site-directed mutagenesis. The increased expression ofxylCmis due to removal of a stem-loop structure without a change of the amino acid sequence of the heterologously expressed enzyme (XylCrec). When gel filtration was applied, purified XylC had molecular masses of 210 kDa and 265 kDa using native gradient gel electrophoresis. The protein consisted of 78-kDa subunits based on SDS gel electrophoresis and contained 6% carbohydrates. XylC and XylCrecexhibited maximum activity at 65°C and pH65°C6.0, a 1-h half-life at 67°C, aKmforp-nitrophenyl-β-d-xyloside of 28 mM, and aVmaxof 276 U/mg and retained 70% activity in the presence of 200 mM xylose, suggesting potential for industrial applications.

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