scholarly journals Purification and Characterization of Glucose-6-Phosphate Dehydrogenase from Camel Liver

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Mahmoud A. Ibrahim ◽  
Abdel-Hady M. Ghazy ◽  
Ahmed M. H. Salem ◽  
Mohamed A. Ghazy ◽  
Mohamed M. Abdel-Monsef

Glucose-6-phosphate dehydrogenase from camel liver was purified to homogeneity by ammonium sulfate precipitation and a combination of DEAE-cellulose, Sephacryl S-300 gel filtration, and 2′, 5′ ADP Sepharose 4B affinity chromatography columns. The specific activity of camel liver G6PD is increased to 1.80438 units/mg proteins with 63-fold purification. It turned out to be homogenous on both native PAGE and 12% SDS PAGE, with a molecular weight of 64 kDa. The molecular weight of the native form of camel liver G6PD was determined to be 194 kDa by gel filtration indicating a trimeric protein. The Km value was found to be 0.081 mM of NADP+. Camel liver G6PD displayed its optimum activity at pH 7.8 with an isoelectric point (pI) of pH 6.6–6.8. The divalent cations MgCl2, MnCl2, and CoCl2 act as activators; on the other hand, CaCl2 and NiCl2 act as moderate inhibitors, while FeCl2, CuCl2, and ZnCl2 are potent inhibitors of camel liver G6PD activity. NADPH inhibited camel liver G6PD competitively with Ki value of 0.035 mM. One binding site was deduced for NADPH on the enzyme molecule. This study presents a simple and reproducible purification procedure of G6PD from the camel liver.

2009 ◽  
Vol 6 (2) ◽  
pp. 249-256
Author(s):  
Baghdad Science Journal

Proteus mirabilis ? -lactamase of local isolates number 4TF represent karkh side and 20TF represent rusafa side of Baghdad were extracted and purified 23.17, 25.23 fold with yield of 36.66 %, 37.5% and specific activity 11.8, 12.6 of unit/ mg protein by DEAE –cellulose and Sepharose 4B (respectively ).Molecular weight of both enzyme was about 35500 Dalton determined by gel filtration. The study indicated that the isoelectric point of purified ? -lactamase that extracted from isolate number 4TF and 20TF was 5.4.


2020 ◽  
Vol 64 (1) ◽  
pp. 153-164
Author(s):  
Mohammed M. Abdel-Monsef ◽  
Hind A. Zidan ◽  
Doaa A. Darwish ◽  
Hassan M. Masoud ◽  
Mohamed S. Helmy ◽  
...  

AbstractThe hyaluronidase enzyme has been used in many such fields of medicine as ophthalmology, orthopaedia, internal medicine, gynecology, surgery, oncology and dermatology. In this study, the hyaluronidase enzyme was purified and characterized for the first time from Egyptian bee venom homogeneously using DEAE-cellulose and Sephacryl S-300 columns. Bee venom hyaluronidase specific activity was 411.7 units/mg protein with 49.9% yield and 3.23-fold purification. The molecular weight of the purified bee venom hyaluronidase native form was 37 kDa. The purified enzyme was found homogeneous on native PAGE and SDS-PAGE, with two congruent subunits of 18.4 kDa and isoelectric point (pI) of 8.6–8.8. The enzyme was found to be stable over a wide range of temperature (20–60°C) and pH (4.5–6.5), and its optimum activity at 37°C, pH 5.4 and 0.15 M NaCl. Km for bee venom hyaluronidase was 0.029 mg/ml hyaluronic acid and its activity was elevated in presence of MgCl2 and ZnCl2 and lowered in presence of FeCl2. Heparin inhibited the hyaluronidase enzyme noncompetitively with a Ki value of 2.9 units heparin and one binding site on the enzyme molecule.


2012 ◽  
Vol 47 (No. 10 - 11) ◽  
pp. 283-288 ◽  
Author(s):  
M. Çiftci ◽  
V. Turkoglu ◽  
S. Aldemir

In vitro effects of penicillin, sulbactam, cefazolin, and amikacine on the activity of the enzyme glucose-6-phosphate dehydrogenase in sheep liver were investigated. Glucose 6-phosphate dehydrogenase was purified from sheep liver, using a simple and rapid method. The purification consisted of two steps, preparation of homogenate and 2’, 5’-ADP Sepharose 4B affinity chromatography. As a result of the two consecutive procedures, the enzyme, having the specific activity of 11.76 EU/mg proteins, was purified with a yield of 35.72% and 1.913 fold. In order to control the enzyme purification SDS polyacrylamide gel electrophoresis (SDS-PAGE) was done. SDS-PAGE showed a single band for the enzyme. In addition, I50 values of the antibiotics were determined by plotting activity % vs. antibiotic concentrations. I50 values were 17.71 mM for penicillin, 27.38 mM for sulbactam, 28.88 mM for cefazolin, and 30.59 mM for amikacine.


2003 ◽  
Vol 69 (12) ◽  
pp. 7116-7123 ◽  
Author(s):  
Ho-Young Shin ◽  
Sun-Young Park ◽  
Jong Hwan Sung ◽  
Dong-Hyun Kim

ABSTRACT Two arabinosidases, α-l-arabinopyranosidase (no EC number) and α-l-arabinofuranosidase (EC 3.2.1.55), were purified from ginsenoside-metabolizing Bifidobacterium breve K-110, which was isolated from human intestinal microflora. α-l-Arabinopyranosidase was purified to apparent homogeneity, using a combination of ammonium sulfate fractionation, DEAE-cellulose, butyl Toyopearl, hydroxyapatite Ultrogel, QAE-cellulose, and Sephacryl S-300 HR column chromatography, with a final specific activity of 8.81 μmol/min/mg.α -l-Arabinofuranosidase was purified to apparent homogeneity, using a combination of ammonium sulfate fractionation, DEAE-cellulose, butyl Toyopearl, hydroxyapatite Ultrogel, Q-Sepharose, and Sephacryl S-300 column chromatography, with a final specific activity of 6.46 μmol/min/mg. The molecular mass ofα -l-arabinopyranosidase was found to be 310 kDa by gel filtration, consisting of four identical subunits (77 kDa each, measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis [SDS-PAGE]), and that ofα -l-arabinofuranosidase was found to be 60 kDa by gel filtration and SDS-PAGE. α-l-Arabinopyranosidase and α-l-arabinofuranosidase showed optimal activity at pH 5.5 to 6.0 and 40°C and pH 4.5 and 45°C, respectively. Both purified enzymes were potently inhibited by Cu2+ and p-chlormercuryphenylsulfonic acid.α -l-Arabinopyranosidase acted to the greatest extent on p-nitrophenyl-α-l-arabinopyranoside, followed by ginsenoside Rb2. α-l-Arabinofuranosidase acted to the greatest extent on p-nitrophenyl-α-l-arabinofuranoside, followed by ginsenoside Rc. Neither enzyme acted on p-nitrophenyl-β-galactopyranoside or p-nitrophenyl-β-d-fucopyranoside. These findings suggest that the biochemical properties and substrate specificities of these purified enzymes are different from those of previously purified α-l-arabinosidases. This is the first reported purification ofα -l-arabinopyranosidase from an anaerobic Bifidobacterium sp.


1987 ◽  
Author(s):  
P P Masci ◽  
A N Whitaker ◽  
J J Morrison ◽  
E A Bennett

Tropidechis carinatus is a venomous elapid snake distributed throughout Eastern Queensland. It has been considered as a tropical relative of Notechis scutatus and, similarly, the crude venom contains an indirect prothrombin activator, which will clot plasma provided that Factor V is present. Myotoxins and neurotoxins are also present. Envenomated patients regularly develop disseminated intravascular coagulation. The crude whole venom of T.carinatus was shown to have five major components by gel filtration, SDS PAGE and HPLC, and even more components by isoelectric focusing. The procoagulant eluted with a molecular weight of 55,000, being found in peak II on gel filtration on Sephadex-G150. The procoagulant was purified using a combination of Sephadex-G150 chromatography and ion-exchange on DEAE Sephadex-A50 and shown to migrate as a single band of molecular weight 55.000 by SDS PAGE. On reduction by β -mercaptoethanol this component was resolvec into u heavy chain of molecular weight 30.000 and a light chain of 25,000. The procoagulant was shown to bind to con A-Sepharose 4B and Blue Sepharose 4B. Coagulation studies using this purified procoagulant confirmed a factor Xa-like activity activating prothrombin in the presence of factor V. The purified fraction is unstable in buffer solutions at 4°C, probably because of trypsin - like autodigestion. Ouchterlony studies of the procoagulants of T.carinatus and N.scutatus show both lines of homogeneity and spurring, indicating similarities but also significant differences between the two proteins. The purified procoagulant was lethal to adult rats, an IV injection of 10 μg killing in 1 - 2 minutes. Death was prevented by prior heparinization, suggesting that the procoagulant is toxic in the absence of neurotoxin and other components.


1986 ◽  
Vol 234 (1) ◽  
pp. 157-162 ◽  
Author(s):  
N N Dewji ◽  
D R De-Keyzer ◽  
J L Stirling

beta-N-Acetylhexosaminidase I2 was purified from human liver by a combination of concanavalin A chromatography, DEAE-cellulose chromatography, gel filtration and affinity chromatography on 2-acetamido-N-(6-aminohexanoyl)-2-deoxy-beta-D-glucopyranosylamine coupled to CNBr-activated Sepharose 4B. Its specific activity was 130 mumol/min per mg of protein compared with values of 150 and 320 mumol/min/mg of protein for beta-N-acetylhexosaminidases A and B purified from the same tissue. Km values for I2, A and B were 1.0 mM, 0.8 mM and 0.74 mM respectively. On gradient gel electrophoresis under non-denaturing conditions, hexosaminidase I2 behaved similarly to A and appeared to have an Mr between 100 000 and 110 000. beta-N-Acetylhexosaminidase I2 was resolved into two major polypeptides, of Mr 56 000 and 29 000, on SDS/polyacrylamide-gel electrophoresis under denaturing conditions. Immunoblotting with anti-(hexosaminidase alpha-subunit) serum confirmed that the 56 000-Mr component was the alpha-subunit and anti-(hexosaminidase B) serum reacted with the 29 000 Mr component. beta-N-Acetylhexosaminidase I2 more closely resembles form A than B, but the features of its structure that allow it to be separated from A on the basis of net charge have not yet been found.


2013 ◽  
Vol 2013 ◽  
pp. 1-9
Author(s):  
Peechapack Somyoonsap ◽  
Vichein Kitpreechavanich ◽  
Somchai Pornbanlualap

A sequence-specific nicking endonuclease from Streptomyces designated as DC13 was purified to near homogeneity. Starting with 30 grams of wet cells, the enzyme was purified by ammonium sulfate fractionation, DEAE cellulose, and phenyl-Sepharose chromatography. The purified protein had a specific activity 1000 units/mg and migrated on SDS-PAGE gel with an estimated molecular weight of 71 kDa. Determination of subunit composition by gel filtration chromatography indicated that the native enzyme is a monomer. When incubated with different DNA substrates including pBluescript II KS, pUC118, pET-15b, and pET-26b, the enzyme converted these supercoiled plasmids to a mixture of open circular and linear DNA products, with the open circular DNA as the major cleavage product. Analysis of the kinetic of DNA cleavage showed that the enzyme appeared to cleave super-coiled plasmid in two distinct steps: a rapid cleavage of super-coiled plasmid to an open circular DNA followed a much slower step to linear DNA. The DNA cleavage reaction of the enzyme required Mg2+ as a cofactor. Based on the monomeric nature of the enzyme, the kinetics of DNA cleavage exhibited by the enzyme, and cofactor requirement, it is suggested here that the purified enzyme is a sequence-specific nicking endonuclease that is similar to type IIS restriction endonuclease.


2011 ◽  
Vol 14 (3) ◽  
pp. 5-11
Author(s):  
Thy Bao Vuong ◽  
Lam Bich Tran ◽  
Duan Luu

Lipase from the hepatopancreas of Tra (Pangasius) catfish was purified by ammonium sulfate fractionation, followed by ion-exhange chromatography on DEAE Cellulose and gel filtration Sephadex G-75. The preparation was homogeneous on polyacrylamide disc gel electrophoresis. The specific activity of the purified enzyme was 37.95 times higher than that of the crude extract. The enzyme showed a molecular weight of 57000 Da. The pH and temperature optima of purified lipase were 8 and 500C respectively. Enzyme activity was enhanced by Ca2+ but inhibited by heavy metals Zn2+, Cd2+, Mg2+.


2014 ◽  
Vol 7 (1) ◽  
pp. 57-63 ◽  
Author(s):  
Safinur Yildirim Çelik ◽  
Nazan Demir ◽  
Yaşar Demir ◽  
Ahmet Adiguzel ◽  
Medine Gulluce

Abstract A bacterial strain was isolated from Pasinler hot spring, Erzurum, Turkey. The purified thermophilic isolate was identified as Geobacillus pallidus P26 and used to produce extracellular pectin lyase (EC 4.2.2.10). Pectin lyase enzyme was purified 34 fold by using DEAE-cellulose anion exchange column chromatography and characterized. Molecular weight of the enzyme was determined as 56 kDa by using Sephadex G-100 gel filtration chromatography. Purification of enzyme was verified by SDS-PAGE. The pH- and temperature optima of enzyme were determined (pH 9.0 and 60°C, respectively). Pectin lyase was mostly stable at 50 oC for 24 hours. Its’ activity decreased to 50 % for 24 h at 60°C. KM and Vmax were calculated as 24.8 mg/mL and 2.28 μmol/L min, respectively. Purified pectin lyase was inhibited by Fe3+, Zn2+, Cu2+, Ca2+, Co2+ and Hg2+ but not by Mg2+. The purified pectin lyase enzyme was used for getting fruits juices. It was found that yields of fruits juices increased when they were compared with control.


2012 ◽  
Vol 61 (1) ◽  
pp. 51-55 ◽  
Author(s):  
PONNUSWAMY VIJAYARAGHAVAN ◽  
S.G. PRAKASH VINCENT

A microorganism hydrolyzing carboxymethyl cellulose was isolated from a paddy field and identified as Bacillus sp. Production of cellulase by this bacterium was found to be optimal at pH 6.5, 37 degrees C and 150 rpm of shaking. This cellulase was purified to homogeneity by the combination of ammonium sulphate precipitation, DEAE cellulose, and sephadex G-75 gel filtration chromatography. The cellulase was purified up to 14.5 fold and had a specific activity of 246 U/mg protein. The enzyme was a monomeric cellulase with a relative molecular mass of 58 kDa, as determined by SDS-PAGE. The enzyme exhibited its optimal activity at 50 degrees C and pH 6.0. The enzyme was stable in the pH range of 5.0 to 7.0 and its stability was maintained for 30 min at 50 degrees C and its activity got inhibited by Hg2+, Cu2+, Zn2+, Mg2+, Na2+, and Ca2+.


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