scholarly journals Brain arylamidase. Purification and characterization of the soluble bovine enzyme

1969 ◽  
Vol 112 (3) ◽  
pp. 335-342 ◽  
Author(s):  
A. S. Brecher ◽  
J. B. Suszkiw

1. An enzyme acting on aminoacyl-β-naphthylamides has been isolated from the soluble fraction of bovine brain and purified 205-fold by means of ammonium sulphate fractionation, hydroxyapatite adsorption and DEAE-Sephadex column chromatography. 2. Arylamidase requires thiol groups for retention of its activity, is heat-labile and is susceptible to freezing. p-Chloromercuribenzoate and N-ethylmaleimide inactivate the enzyme rapidly. 3. Metal ions are not required for its activity, but stimulation by Mn2+ and Mg2+ and inactivation by Co2+ and Zn2+ are observed. 4. Optimum pH7·5 in phosphate buffer was exhibited for all substrates tested except l-leucyl-β-naphthylamide, for which optimum pH is 6·5. 5. Km values for a number of substrates have been obtained and substrate inhibition at high concentrations was demonstrated. 6. The molecular weight is approx. 70000 as determined by Sephadex-gel filtration.

1992 ◽  
Vol 288 (2) ◽  
pp. 475-482 ◽  
Author(s):  
I Ishii-Karakasa ◽  
H Iwase ◽  
K Hotta ◽  
Y Tanaka ◽  
S Omura

For the purification of a new type of endo-alpha-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242 (endo-GalNAc-ase-S) [Iwase, Ishii, Ishihara, Tanaka, Omura & Hotta (1988) Biochem. Biophys. Res. Commun. 151, 422-428], a method for assaying enzyme activity was established. Using purified pig gastric mucus glycoprotein (PGM) as the substrate, oligosaccharides liberated from PGM were pyridylaminated, and the reducing terminal sugars of oligosaccharides larger than Gal beta 1-3GalNAc were analysed by h.p.1.c. The crude enzyme of endo-GalNAc-ase-S was prepared as an 80% (w/v) ammonium sulphate precipitate from the concentrated culture medium. The enzyme was partially purified by gel chromatofocusing and subsequent DEAE-Toyopearl chromatography. Endo-enzyme activity eluted around pI 4.8 on a gel chromatofocusing column and eluted with 0.19-0.25 M-NaCl on a DEAE-Toyopearl column. In the enzyme fraction obtained, no exo-glycosidases or proteases could be detected. The molecular mass of the enzyme was estimated as 105 kDa by gel filtration, and the optimum pH was 5.5. Endo-GalNAc-ase-S hydrolysed the O-glycosidic linkage between GalNAc and Ser (Thr) in 3H-labelled and unlabelled asialofetuin, liberating both the disaccharide (Gal beta 1-3GalNAc) and the tetrasaccharide [Gal beta 1-3 (Gal beta 1-4GlcNAc beta 1-6)GalNAc]. When endo-alpha-N-acetylgalactosaminidase from Alcaligenes sp. (endo-GalNac-ase-A) was incubated with 3H-labelled and unlabelled asialofetuin, only the disaccharide (Gal beta 1-3GalNAc) was liberated.


2013 ◽  
Vol 10 (3) ◽  
pp. 844-853
Author(s):  
Baghdad Science Journal

Endoglucanase produced from Aspergillus flavus was purified by several steps including precipitation with 25 % ammonium sulphate followed by Ion –exchange chromatography, the obtained specific activity was 377.35 U/ mg protein, with a yield of 51.32 % .This step was followed by gel filtration chromatography (Sepharose -6B), when a value of specific activity was 400 U/ mg protein, with a yield of 48 %. Certain properties of this purified enzyme were investigated, the optimum pH of activity was 7 and the pH of its stability was 4.5, while the temperature stability was 40 °C for 60 min. The enzyme retained 100% of its original activity after incubation at 40 °C for 60 min; the optimum temperature for enzyme activity was 40 °C.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Hanaa H. Abd El Baky ◽  
Gamal S. El Baroty

L-asparaginase (L-AsnA) is widely distributed among microorganisms and has important applications in medicine and in food technology sectors. Therefore, the ability of the production, purification, and characterization of AsnA fromSpirulina maxima(SM) were tested. SM cultures grown in Zarrouk medium containing different N2(in NaNO3form) concentrations (1.25, 2.50, and 5.0 g/L) for 18 days contained a significant various quantity of dry biomass yields and AsnA enzyme levels. MS L-AsnA activity was found to be directly proportional to the N2concentration. The cultures of SM at large scales (300 L medium, 5 g/L N2) showed a high AsnA enzyme activity (898 IU), total protein (405 mg/g), specific enzyme activity (2.21 IU/mg protein), and enzyme yield (51.28 IU/L) compared with those in low N2cultures. The partial purification of crude MS AsnA enzyme achieved by 80% ammonium sulfate AS precipitated and CM-Sephadex C-200 gel filtration led to increases in the purification of enzyme with 5.28 and 10.91 times as great as that in SM crude enzymes. Optimum pH and temperature of purified AsnA for the hydrolyzate were 8.5 and 37 ± 0.2°C, respectively. To the best of our knowledge, this is the first report on L-asparaginase production inS. maxima.


2010 ◽  
Vol 4 (2) ◽  
pp. 78-85
Author(s):  
Jasim M. Awdaa

Inulinase was produced from local isolate of Aspergillus niger J3. The inulinase was purified by two steps included precipitation by amonium sulphate at (30-80) % sa-turation and gel filtration on sephadex G100. The final purification folds and the yield of the enzyme were 3.15 times and 28.24%, respectively. The purified enzyme has the following characteristics: The optimum pH of the enzyme activity was 5.5. The enzyme was most stable at pH (4.5 - 6). The optimum temperature for its activity was 45c. The enzyme retained its original activity when incubates at (30-55) c for 20 minutes. Mercury chloride inhibited the enzyme completely at concentration of 10mM, cupper sulphate and calisium chloride inhibited the enzyme at concentrations of 85% and 7% respectively. It was revealed that the enzyme had the efficiency to hydrolyze 87% of 5% inulin solution when treated at 45c for 120 min.


1982 ◽  
Vol 47 (4) ◽  
pp. 1139-1148 ◽  
Author(s):  
Karel Hauzer ◽  
Linda Servítová ◽  
Tomislav Barth ◽  
Karel Jošt

Post-proline endopeptidase was isolated from pig kidneys and partially purified. The procedure consisted of fractionation with ammonium sulphate, ion exchange chromatography on DEAE-Sephadex A-50, gel filtration on Sephadex G-200 and rechromatography on DEAE-Sephadex A-50. The preparation had 55 times higher specific activity than the crude extract and did not contain any contaminating enzymic activities. The enzyme cleaved a number of proline-containing peptides and was strictly specific in catalyzing the hydrolysis of the peptide bond on the carboxyl side of the proline residue. The optimum pH for the hydrolysis of the synthetic peptides benzyl-oxycarbonylglycyl-prolyl-leucyl-glycinamide and benzyloxycarbonyl-glycyl-proline β-naphtylamide was 7.8-8.0 and, in the case of benzyloxycarbonylglycyl-proline p-nitroanilide, 7.2 to 7.5. For the hydrolysis of the tetrapeptide benzyloxycarbonylglycyl-prolyl-leucyl-glycinamide, the Km value of 75 μ mol l-1 was obtained.


1983 ◽  
Vol 61 (1) ◽  
pp. 54-62 ◽  
Author(s):  
Kiyoshi Takeuchi

Exo-β-1,3-glucanase from the sea urchin embryos was purified 114-fold from the initial hatching supernatant by the following procedures: (a) gel filtration on Sephadex G-100; (b) hydrophobic chromatography on 4-phenylbutylamine-Sepharose (PBA-Sepharose); (c) two ion-exchange chromatographic steps on DEAE-cellulose; (d) gel filtration on Ultrogel AcA 34; (e) gel filtration on Sephadex G-100. The purified enzyme contained 2.2% carbohydrate and gave a single protein band corresponding to a molecular weight of 136 000 following electrophoresis on sodium dodecyl sulfate (SDS) – urea – polyacrylamide gel. Gel filtration on Ultrogel AcA 34 with a nondenaturing solvent gave a molecular weight of 130 000 ± 6000. The enzyme displayed an optimum pH at 5.0–5.5 and hydrolysed laminarin and PS(curdlan)-beads at the nonreducing ends, releasing glucose. Although activity of the purified enzyme was not affected by SDS, urea, some divalent ions, and 2-mercaptoethanol, both dithiothreitol and Hg2+ were markedly inhibitory.


2019 ◽  
Vol 6 (6) ◽  
pp. 280-286
Author(s):  
Aarthi Ravichandran ◽  
Ramya G Rao ◽  
Maheswarappa Gopinath ◽  
Manpal Sridhar

Versatile Peroxidases are high redox potential peroxidases capable of degrading lignin of lignocellulosic crop residues. Hence Versatile Peroxidases are prominent biocatalysts in upgrading lignocellulosic biomass for biotechnological applications. In the interest of exploiting the potential of Versatile Peroxidase in improving the digestibility of crop residues through delignification, a novel Versatile Peroxidase was purified and characterized from the immobilized cultures of native isolate Lentinus squarrosulus. The enzyme was purified with a specific activity of 62 U/mg through ion exchange and gel filtration chromatographic procedures. The enzyme possessed high affinity towards RB5 and manganese with a Km value of 6.84 µM for RB5 and 0.15 mM for manganese. The optimum temperature for oxidation was identified to be 30°C and optimum pH for manganese and RB5 oxidation was 5 and 3 respectively. Reactivity of the enzyme towards diverse substrates was investigated besides studying the effect of metal ions and inhibitors on RB5 oxidation. The enhanced potential of this purified Versatile Peroxidase in biodegradation of crop residues was demonstrated through augmentation of digestibility of finger millet and paddy straws by 20%.The results demonstrated that Versatile Peroxidase from Lentinus squarrosulus is capable of enhancing the nutritive value of crop residues through delignification


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 520f-521
Author(s):  
Chunlin Xiao ◽  
Mosbah M. Kushad

The polyamine and ethylene biosynthetic pathways utilize methionine as substrate for their biosynthesis. However, methionine pool in fruits and other plant tissues is very limited and is not sufficient to accommodate the amount of ethylene or polyamines that are synthesized during development and senescence. To compensate for the insufficient amount of methionine, plant tissues have evolved a mechanism to salvage 5'-deoxy-5'-methylthioadenosine (MTA), a by-product of polyamine and ethylene biosynthesis, back into methionine. The first enzyme involved in this salvage pathway is MTA nucleosidase. Purification of MTA nucleosidase from mature avocado fruits showed that there are two isozymes of MTA nucleosidase. In this study we will report on the purification of one of the isozymes, MTA nucleosidase I. Using ammonium sulfate fractionation, DEAE-Sepharose, Sephadex G-100 gel filtration, and hydroxyapatite chromatography, the isozyme was purified 3712-fold yielding about 11% protein. The isozyme migrated as a single band of 40 kDa molecular weight on SDS-polyacrylamide gel electrophoresis. MTA nucleosidase I exhibited an optimum pH of 7.2 and optimum temperature of 55 °C. The Km value of the isozyme for its substrate MTA is 7.69 μM and the Vmax is 58.82 × 10–6 μmol·min-1. Incubation of MTA nucleosidase I with analogs of MTA, 2.5 mM ethylthioadenosine and 2.5 mM 5'-S-isobutyl-5'-deoxyadenosine, completely blocked its activity. The isozyme activity was also inhibited by putrescine, spermidine, and spermine.


2020 ◽  
Vol 38 (1B) ◽  
pp. 26-33
Author(s):  
Azhar M. Haleem

The objective of the present study was to extract and purified proliferative factor for peripheral blood lymphocytes from Nigella sativa seeds. Dimeric 44, 32 and 26 -kDa glucosamine-specific lectins were extracted and purified from seeds of N. sativa L. by using different ionic strength solvents (deionized distilled water, phosphate buffer slain and 0.1 M HCl) purification procedure included, precipitation in saturated ammonium sulphate, then Sephadex G-100 gel filtration was used for further purification, finally electrophoresis by polyacrylamide gel to estimate the molecular weight in the presence of sodium dodecylsulphate. Single absorbance peak at 280 nm was recorded in each extracted method.  The temperature and pH value on mitogenic activity was studied in temperature ranged from 4°C-60°C, the mitogenic activity reduced with gradual increase of temperatures, 50% of activity lost at temperature greater than 40°C, while the optimum pH for mitogenic activity ranged from 5-9, at pH value less than 3, and greater than 12 the activity disappeared. Interestingly, lectin extracted from N. sativa seeds have high activity especially that extracted with 0.1 M HCl and showed stability at temperature from 4°C to 10°C and pH from 5 to 9. The pure lectin is a homodimeric molecule of 26 kDa with subunit molecular mass of 12.9 kDa. The novel lectin  exceed the PHA-Sigma in mitogenic activity.


2012 ◽  
Vol 87 (2) ◽  
pp. 212-221 ◽  
Author(s):  
M. Dmitryjuk ◽  
M. Dopieralska ◽  
E. Łopieńska-Biernat ◽  
R.J. Frączek

AbstractTrehalose 6-phosphate (T6P) synthase (TPS;EC2.4.1.15) was isolated from muscles ofAscaris suumby ammonium sulphate fractionation, ion-exchange DEAE SEPHACELTManion exchanger column chromatography and Sepharose 6B gel filtration. On sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE), 265-fold purified TPS exhibited a molecular weight of 66 kDa. The optimum pH and temperature of the purified enzyme were 3.8–4.2 and 35°C, respectively. The isoelectric point (pI) of TPS was pH 5.4. The studied TPS was not absolutely substrate specific. Besides glucose 6-phosphate, the enzyme was able to use fructose 6-phosphate as an acceptor of glucose. TPS was activated by 10 mMMgCl2, 10 mMCaCl2and 10 mMNaCl. In addition, it was inhibited by ethylenediaminetetra-acetic acid (EDTA), KCl, FeCl3and ZnCl2. Two genes encoding TPS were isolated and sequenced from muscles of the parasite. Complete coding sequences fortps1(JF412033.2) andtps2(JF412034.2) were 3917 bp and 3976 bp, respectively. Translation products (AEX60788.1 and AEX60787.1) showed expression to the glucosyltransferase-GTB-type superfamily.


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