Search results

1

Characterization of an acidic α-galactosidase from hemp (Cannabis sativa L.) seeds and its application in removal of raffinose family oligosaccharides (RFOs)

100%

Zhang W., Du F., Tian G., Zhao Y., Wang H., Ng T.

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2018

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vol. 65

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issue 3

383-389

EN

An acidic α-galactosidase designated as hemp seed α-galactosidase (HSG) was purified from hemp (Cannabis sativa L.) seeds. By means of chromatographic procedures which involved chromatography on the cation-exchangers CM-cellulose and SP-Sepharose, chromatography on the anion-exchangers DEAE-cellulose and Q-Sepharose, and gel filtration on Superdex 75 using fast protein liquid chromatography, HSG was purified to electrophoretic homogeneity. Results of SDS-PAGE and gel filtration on FPLC Superdex 75 revealed that the enzyme was a monomeric protein with a molecular weight of 38 kDa. Sequences of the inner peptides of the α-galactosidase obtained by MALDI-TOF-MS showed that HSG was a novel α-galactosidase since there was a little similarity to the majority of α-galactosidases recorded in the literature. A pH of 3.0 and a temperature of 50°C were optimal for the activity of the enzyme. The activity of HSG was inhibited by the chemical modification with N-bromosuccinimide (NBS) reagent. HSG contained 16 tryptophan residues and two tryptophan residues on the surface, which were crucial to the α-galactosidase activity. The heavy metal ions Cd2+, Cu2+, Hg2+ and Zn2+ inhibited its activity. The Km and Vmax for the hydrolysis of pNPGal (4-nitrophenyl α-D-galactopyranoside) were respectively 0.008 mM and 68 μM min-1 mg-1. HSG also catalyzed the hydrolysis of raffinose and other natural substrates. Hence the α-galactosidase possesses a tremendous potential for food and feed industries in the elimination of indigestible oligosaccharides from leguminous products.

2

Optimal expression and purification of sapelovirus A structural protein VP1, and its immunogenicity in mice

100%

Zhao T. T., Cui L., Chen L., Li J. J., Liang Q. L., Wu P. J., Yu X. Q., Zhang Z. H., Hua X. G.

Polish Journal of Veterinary Sciences

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2018

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vol. 21

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issue 3

3

Purification and characterization of a novel laccase from the mushroom Pleurotus nebrodensis

100%

Tian G.-T., Zhang G.-Q., Wang H.-X., Ng T. B.

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2012

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vol. 59

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issue 3

407-412

EN

A novel laccase with a molecular mass of 64 kDa and the N-terminal sequence AIGPDDTINF was isolated from fresh fruiting bodies of the mushroom Pleurotus nebrodensis. The purification protocol comprised ion exchange chromatography on DEAE-cellulose, CM-cellulose, and Q-Sepharose, and gel filtration on Superdex 75. The laccase was adsorbed on DEAE-cellulose and Q-Sepharose, but not on CM-cellulose. It demonstrated an optimal temperature of 70°C. The enzyme activity increased steadily over the temperature range 20°C-70°C. There was only a slight reduction in activity at 80°C. However, all activity disappeared following exposure to 100°C for 10 minutes. The enzyme activity changed only slightly over the pH range 3-5, with the optimum at pH 5, but underwent a precipitous decline when the pH was elevated to 6, and was undetectable at pH 8 and pH 9.

4

Purification and characterization of a novel metalloprotease from fruiting bodies of Oudemansiella radicata

100%

Geng X., Te R., Tian G., Zhao Y., Zhao L., Wang H., Ng T.

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2017

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vol. 64

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issue 3

477-483

EN

In this study, a 39-kDa metalloprotease was purified from a rare edible mushroom with health-promoting activities, Oudemansiella radicata, using a purification protocol which entailed anion exchange chromatography on DEAE-cellulose and Q-Sepharose columns and gel filtration by fast protein liquid chromatography on a Superdex 75 column. Some peptide sequences were obtained by LC-MS/MS analysis and one of the sequences, DAWIQADVNR, manifested 90% identity to Coprinopsis cinerea metalloprotease. The optimal reaction pH and temperature for Oudemansiella radicata protease were pH 7.0 and 50°C, respectively. The protease was purified 79-fold and demonstrated a specific protease activity of 2.42 U/mg. The Km of the purified protease for the casein substrate was 0.65 mg/mL at pH 7.0 and 50°C. The activity of the protease was inhibited by Cd2+, Hg2+, Cu2+, Pb2+ and Fe3+ ions, but was enhanced by K+, Mn2+ and Fe2+ ions. The marked suppression of the protease activity by EDTA indicates that the protease is a metalloprotease.

5

ISOLATION AND PURIFICATION OF CHITINOLYTIC ENZYMES OF RUMEN CILIATES Eudiplodinium maggii

100%

Miltko R., Bełżecki G., Kasperowicz A., Michałowski T.

Progress on Chemistry and Application of Chitin and its Derivatives

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2010

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vol. 15

189 - 196

EN

Results of the earlier studies suggested an involvement of ciliates Eudiplodinium maggii in the digestion and metabolism of chitin in the rumen. In the presented paper we described the results on the preliminary identification and characterization of chitinolytic enzymes of this ciliate as well as the method of their purification. The protozoal crude enzyme preparation was used as source of enzymes, whereas the molecular filtration on Sephadex G-150 (single step method) or separation of protein by precipitation with ammonium sulfate followed by molecular filtration (two step method) were applied to purify the identified enzymes. The identification studies resulted in the detection of endochitinase, exochitinase and N-acetyl-D-glucosaminidase. The highest activity of identified enzymes were obtained in 4.0 - 4.5 pH and at 45 - 50 °C. Results of the comparative study on purification procedures showed that the single-step method enabled us to obtain enzymes of higher purity and higher activity than the two-step purification method.

6

Characterization of a novel laccase purified from the fungus Hohenbuehelia serotina and its decolourisation of dyes

100%

Xu Y., Lu Y., Zhang R., Wang H., Liu Q.

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2016

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vol. 63

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issue 2

273-279

EN

A novel laccase was purified from the white rot fungus, Hohenbuehelia serotina, to investigate the applications of this laccase in the decoloration of various dyes. SDS-PAGE revealed a single band of this laccase corresponding to a molecular weight of approximately 57.8 kDa. The enzyme showed activity towards several substrates, the most sensitive of which was 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS). The highest enzymatic activity using ABTS as a substrate was observed at pH 6.8 and 30°C. The enzyme activity was found to be significantly enhanced in the presence of Zn2+ ions and inhibited by Fe2+ ions. Moreover, SDS and β-mercaptoethanol were inhibitory, and inhibition by L-cysteine was observed while EDTA and DMSO had almost no inhibitory effect. The laccase could effectively decolorize seven different dyes within 30 minutes at 40°C.

7

Effects of acid treatment duration and sulfuric acid molarity on purification of multi-walled carbon nanotubes

100%

Mortazavi S., Novinrooz A., Reyhani A., Mirershadi S.

Open Physics

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2010

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vol. 8

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issue 6

940-946

EN

Multi-walled carbon nanotubes were synthesized using a Fe-Ni bimetallic catalyst supported by MgO using thermal chemical vapor deposition. Purification processes to remove unwanted carbon structures and other metallic impurities were carried out by boiling in sulfuric acid solution. Various analytical techniques such as TGA/DSC, Raman spectroscopy, SEM, HRTEM and EDAX were employed to investigate the morphology, graphitization and quality of the carbon nanotubes. The obtained results reveal the molarity of sulfuric acid and immersed time of the carbon nanotubes in the acid solution is very effective at purifying multi-walled carbon nanotubes. It was also found that 5 M concentration of boiling sulfuric acid for a 3 h treatment duration led to the highest removal of the impurities with the least destructive effect. Moreover, it was observed that acid treatment results in decreasing of CNTs’ diameter.

8

A novel alkaline protease from wild edible mushroom Termitomyces albuminosus

100%

Zheng S., Wang H., Zhang G.

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2011

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vol. 58

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issue 2

269-274

EN

A protease with a molecular mass of 30 kDa and the N-terminal sequence of GLQTNAPWGLARSS, was isolated from fresh fruiting bodies of the wild edible mushroom Termitomyces albuminosus. The purification protocol included ion exchange chromatography on DEAE-cellulose, Q-Sepharose, SP-Sepharose and FPLC-gel filtration on Superdex 75. The protein was unadsorbed on DEAE-cellulose and Q-Sepharose, but adsorbed on SP-Sepharose. The optimal pH and temperature of the purified enzyme were 10.6 and 60 °C, respectively. The enzyme was stable in the presence of 2 % (v/v) Tween 80 and 4 M urea. More than 80 % of the enzyme activity was retained in 2 % (v/v) Triton X 100, 54 % in 10 mM EDTA and 31 % in 2 % (w/v) SDS. The enzyme was strongly inhibited by phenylmethylsulfonyl fluoride (PMSF), but not inhibited by dithiothreitol (DTT), pepstatin or lima bean trypsin inhibitor suggesting that it was a serine protease but not a trypsin-like one. The protease was inhibited by Hg2+, Cu2+, and Fe3+ ions. The Km and Vmax values of the purified enzyme for casein were 8.26 mg ∙ ml-1 and 0.668 mg ∙ ml-1 ∙ min-1, respectively.

9

Carbon, natural and synthetic sorbents for decontamination of objects of ecosystems from pathogenic microflora

100%

Shvets D., Denisova T., Strelko V.

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EN

Physico-chemical characteristics and sorption activity of carbon, organosilica sorbents and their modified forms towards proteins, possessing specific activity, and cholerae vibrio have been studied. It was found, that carbon materials modified by copper (II) effectively extracts cholerae vibrio (100%) and may be recommended for disinfection of drinking water. Sorption capacity of organosilica sorbents and their modified by copper (II) forms towards pathogenic microflora (E.coli, St.aureus, Ps.aeruginosa) depending on the composition of the sorbents, concentration of the modified reagent, pH of medium have been evaluated. The rows of the increase of sorption of pathogenic microorganisms by synthetic sorbents in water-salt solutions were established: Al(III)

10

Purification and properties of an α-(1 → 3)-glucanase (EC 3.2.1.84) from Trichoderma harzianum and its use for reduction of artificial dental plaque accumulation

88%

Wiater A., Pleszczyńska M., Rogalski J., Szajnecka L., Szczodrak J.

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2013

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vol. 60

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issue 1

123-128

EN

Extracellular α-(1 → 3)-glucanase (mutanase, EC 3.2.1.84) produced by Trichoderma harzianum CCM F-340 was purified to homogeneity by ultrafiltration followed by ion exchange and hydrophobic interaction chromatography, and final chromatofocusing. The enzyme was recovered with an 18.4-fold increase in specific activity and a yield of 4.3%. Some properties of the α-(1 → 3)-glucanase were investigated. The molecular mass of the enzyme is 67 kDa, as estimated by SDS/PAGE, its isoelectric point 7.1, and the carbohydrate content 3%. The pH and temperature optima are 5.5 and 45°C, respectively. The enzyme is stable over a pH range of 4.5-6.0 and up to 45°C for 1 h. The Km and Vmax under standard assay conditions are 0.73 mg/ml and 11.39 x 10-2 µmol/min/mg protein, respectively. The enzyme activity is stimulated by addition of Mg2+ and Na+, and significantly inhibited by Hg2+. The α-(1 → 3)-glucanase preparation preferentially catalyzed the hydrolysis of various streptococcal mutans and fungal α-(1 → 3)-glucans. The 20-residue N-terminal sequence of the enzyme is identical with those of other α-(1 → 3)-glucanases from the genus Trichoderma, and highly similar to those from other fungi. The purified α-(1 → 3)-glucanase was effective in preventing artificial dental plaque formation. The easy purification from fermentation broth and high stability, and the effective inhibition of oral biofilm accumulation make this α-(1 → 3)-glucanase highly useful for industrial and medical application.

11

Characterisation and molecular dynamic simulations of J15 asparaginase from Photobacterium sp. strain J15

88%

Yaacob M., Hasan W., Ali M., Rahman R., Salleh A., Basri M., Leow T.

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2014

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vol. 61

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issue 4

745-752

EN

Genome mining revealed a 1011 nucleotide-long fragment encoding a type I l-asparaginase (J15 asparaginase) from the halo-tolerant Photobacterium sp. strain J15. The gene was overexpressed in pET-32b (+) vector in E. coli strain Rosetta-gami B (DE3) pLysS and purified using two-step chromatographic methods: Ni2+-Sepharose affinity chromatography and Q-Sepharose anion exchange chromatography. The final specific activity and yield of the enzyme achieved from these steps were 20 U/mg and 49.2%, respectively. The functional dimeric form of J15-asparaginase was characterised with a molecular weight of ~70 kDa. The optimum temperature and pH were 25°C and pH 7.0, respectively. This protein was stable in the presence of 1 mM Ni2+ and Mg2+, but it was inhibited by Mn2+, Fe3+ and Zn2+ at the same concentration. J15 asparaginase actively hydrolysed its native substrate, l-asparagine, but had low activity towards l-glutamine. The melting temperature of J15 asparaginase was ~51°C, which was determined using denatured protein analysis of CD spectra. The Km, Kcat, Kcat/Km of J15 asparaginase were 0.76 mM, 3.2 s-1, and 4.21 s-1 mM-1, respectively. Conformational changes of the J15 asparaginase 3D structure at different temperatures (25°C, 45°C, and 65°C) were analysed using Molecular Dynamic simulations. From the analysis, residues Tyr24, His22, Gly23, Val25 and Pro26 may be directly involved in the 'open' and 'closed' lid-loop conformation, facilitating the conversion of substrates during enzymatic reactions. The properties of J15 asparaginase, which can work at physiological pH and has low glutaminase activity, suggest that this could be a good candidate for reducing toxic effects during cancer treatment.

12

Heterologous expression and initial characterization of recombinant RbcX protein from Thermosynechococcus elongatus BP-1 and the role of RbcX in RuBisCO assembly

88%

Tarnawski M., Gubernator B., Kolesinski P., Szczepaniak A.

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2008

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vol. 55

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issue 4

777-785

EN

In the cyanobacterial RuBisCO operon from Thermosynechococcus elongatus the rbcX gene is juxtaposed and cotranscribed with the rbcL and rbcS genes which encode large and small RuBisCO subunits, respectively. It has been suggested that the rbcX position is not random and that the RbcX protein could be a chaperone for RuBisCO. In this study, the RbcX protein from T. elongatus was overexpressed, purified and preliminary functional studies were conducted. The recombinant protein purified from Escherichia coli extracts was predominantly present in a soluble fraction in a dimeric form. Coexpression experiments have demonstrated that RbcX can mediate RbcL dimer (L2) formation, and that it is essential for the L8 core complex assembly. This is the first characterization of the RbcX protein from a thermophilic organism.

13

A novel lectin with antiproliferative activity from the medicinal mushroom Pholiota adiposa

88%

Zhang G. Q., Sun J., Wang H. X., Ng T. B.

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issue 3

415-421

EN

Little was known about biological activities of compounds from the medicinal mushroom of the genus Pholiota. A lectin from the Pholiota adiposa has now been isolated and its properties tested. The isolation procedure included ion exchange chromatography on DEAE-cellulose and CM-cellulose, and fast protein liquid chromatography-gel filtration (FPLC) on Superdex 75. The lectin was composed of two identical subunits, each with a molecular mass of 16 kDa. Its N-terminal amino-acid sequence showed little similarity to sequences of other Agaricales lectins. The hemagglutinating activity of the lectin was stable at temperatures up to 50°C, and in NaOH and HCl solutions with concentrations less than 25 mM. It was inhibited by inulin (12.5-200 mM), but enhanced by Cu2+ (6.25-25 mM), Fe2+ (12.5-25 mM), and Al3+ (6.25-25 mM) ions. The lectin showed antiproliferative activity toward hepatoma Hep G2 cells and breast cancer MCF7 cells with an IC50 of 2.1 µM and approximately 3.2 µM, respectively. It exhibited HIV-1 reverse transcriptase inhibitory activity with an IC50 of 1.9 µM. When compared with P. aurivella lectin, the only Pholiota lectin published to date, P. adiposa lectin differs in chromatographic behavior, molecular mass, N-terminal sequence, and effect of cations on hemagglutinating activity. In the case of the lectin from P. aurivella, its antifungal, antiproliferative, and HIV-1 reverse transcriptase inhibitory activities have not been determined.

14

Identification and properties of the Deinococcus grandis and Deinococcus proteolyticus single-stranded DNA binding proteins (SSB)

88%

Filipkowski P., Kur J.

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2007

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vol. 54

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issue 1

79-87

EN

To study the biochemical properties of SSB's from Deinococcus grandis (DgrSSB) and Deinococcus proteolyticus (DprSSB), we have cloned the ssb genes obtained by PCR and have developed Escherichia coli overexpression systems. The genes consist of an open reading frame of 891 (DgrSSB) and 876 (DprSSB) nucleotides encoding proteins of 296 and 291 amino acids with a calculated molecular mass of 32.29 and 31.33 kDa, respectively. The amino-acid sequence of DgrSSB exhibits 45%, 44% and 82% identity and the amino-acid sequence of DprSSB reveals 43%, 43% and 69% identity with Thermus aquaticus (TaqSSB), Thermus thermophilus (TthSSB) and Deinococcus radiodurans SSBs, respectively. We show that DgrSSB and DprSSB are similar to Thermus/Deinococcus SSBs in their biochemical properties. They are functional as homodimers, with each monomer encoding two single-stranded DNA binding domains (OB-folds). In fluorescence titrations with poly(dT), both proteins bind single-stranded DNA with a binding site size of about 33 nt per homodimer. In a complementation assay in E. coli, DgrSSB and DprSSB took over the in vivo function of EcoSSB. Thermostability with half-lives of about 1 min at 65-67.5°C make DgrSSB and DprSSB similar to the known SSB of Deinococcus radiodurans (DraSSB).

15

Thermostable Pyrococcus woesei β-D-galactosidase - high level expression, purification and biochemical properties

88%

Wanarska M., Kur J., Pladzyk R., Turkiewicz M.

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2005

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vol. 52

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issue 4

781-787

EN

The gene encoding β-D-galactosidase from Pyrococcus woesei was PCR amplified, cloned, expressed in Escherichia coli under the control of an inducible T7 promoter, purified and characterized. The expression system was developed by the construction of recombinant plasmid, based on the high copy number pUET1 vector, giving four times more efficient expression of P. woesei β-D-galactosidase (20 mg of enzyme from 1 liter of culture) than that obtained from a previously constructed one. The recombinant enzymes were purified in a two-step procedure: double heat-denaturation of E. coli cell proteins and affinity chromatography on p-aminobenzyl 1-thio-β-D-galactopyranoside-agarose. To achieve efficient purification of P. woesei β-D-galactosidase by immobilized metal-ion affinity chromatography (IMAC), a His-tag was placed either at the N- or the C-terminal of the coding sequence. The obtained fusion proteins revealed the same specific activity of approximately 5400 U/mg, which was 10 times lower than the wild-type β-D-galactosidase (51100 U/mg). The activity of P. woesei β-D-galactosidase was enhanced by thiol compounds, Mg2+ ions and D-galactose, and was inhibited by heavy metal ions and D-glucose, while Ca2+ ions had no effect.

16

Molecular cloning, recombinant expression, and purification of osteocalcin in sika deer (Cervus nippon) antler

75%

Li X., Liu M., Bai X., Li Y., Zhao Y., Wang S., Wang J., Li X., Liu M., Bai X., Li Y., Zhao Y., Wang S., Wang J.

Polish Journal of Veterinary Sciences

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2019

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issue 1

17

A novel alkaline protease with antiproliferative activity from fresh fruiting bodies of the toxic wild mushroom Amanita farinosa

75%

Sun J., Zhao Y., Chai H., Wang H., Ng T. B.

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2011

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vol. 58

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issue 4

567-572

EN

A novel protease with a molecular mass of 15 kDa was purified from fresh fruiting bodies of the wild mushroom Amanita farinosa. The purification protocol entailed anion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, cation exchange chromatography on SP-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The protease was unadsorbed on DEAE-cellulose but adsorbed on Affi-gel blue gel and SP-Sepharose. It demonstrated a single 15-kDa band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS/PAGE) and a 15-kDa peak in gel filtration. The optimal pH and optimal temperature of the protease were pH 8.0 and 65 °C, respectively. Proliferation of human hepatoma HepG2 cells was inhibited by the protease with an IC50 of 25 µM. The protease did not have antifungal or ribonuclease activity.

18

Improved downstream process for the production of plasmid DNA for gene therapy

75%

Urthaler J., Buchinger W., Necina R.

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2005

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vol. 52

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issue 3

703-711

EN

Gene therapy and genetic vaccines promise to revolutionize the treatment of inherited and acquired diseases. Since viral vectors are generally associated with numerous disadvantages when applied to humans, the administration of naked DNA, or DNA packed into lipo- or polyplexes emerge as viable alternatives. To satisfy the increasing demand for pharmaceutical grade plasmids we developed a novel economic downstream process which overcomes the bottlenecks of common lab-scale techniques and meets all regulatory requirements. After cell lysis by an in-house developed gentle, automated continuous system the sequence of hydrophobic interaction, anion exchange and size exclusion chromatography guarantees the separation of impurities as well as undesired plasmid isoforms. After the consecutive chromatography steps, adjustment of concentration and final filtration are carried out. The final process was proven to be generally applicable and can be used from early clinical phases to market-supply. It is scaleable and free of animal-derived substances, detergents (except lysis) and organic solvents. The process delivers high-purity plasmid DNA of homogeneities up to 98% supercoiled form at a high yield in any desired final buffer.

Refine search results

Characterization of an acidic α-galactosidase from hemp (Cannabis sativa L.) seeds and its application in removal of raffinose family oligosaccharides (RFOs)

Optimal expression and purification of sapelovirus A structural protein VP1, and its immunogenicity in mice

Purification and characterization of a novel laccase from the mushroom Pleurotus nebrodensis

Purification and characterization of a novel metalloprotease from fruiting bodies of Oudemansiella radicata

ISOLATION AND PURIFICATION OF CHITINOLYTIC ENZYMES OF RUMEN CILIATES Eudiplodinium maggii

Characterization of a novel laccase purified from the fungus Hohenbuehelia serotina and its decolourisation of dyes

Effects of acid treatment duration and sulfuric acid molarity on purification of multi-walled carbon nanotubes

A novel alkaline protease from wild edible mushroom Termitomyces albuminosus

Carbon, natural and synthetic sorbents for decontamination of objects of ecosystems from pathogenic microflora

Purification and properties of an α-(1 → 3)-glucanase (EC 3.2.1.84) from Trichoderma harzianum and its use for reduction of artificial dental plaque accumulation

Characterisation and molecular dynamic simulations of J15 asparaginase from Photobacterium sp. strain J15

Heterologous expression and initial characterization of recombinant RbcX protein from Thermosynechococcus elongatus BP-1 and the role of RbcX in RuBisCO assembly

A novel lectin with antiproliferative activity from the medicinal mushroom Pholiota adiposa

Identification and properties of the Deinococcus grandis and Deinococcus proteolyticus single-stranded DNA binding proteins (SSB)

Thermostable Pyrococcus woesei β-D-galactosidase - high level expression, purification and biochemical properties

Molecular cloning, recombinant expression, and purification of osteocalcin in sika deer (Cervus nippon) antler

A novel alkaline protease with antiproliferative activity from fresh fruiting bodies of the toxic wild mushroom Amanita farinosa

Improved downstream process for the production of plasmid DNA for gene therapy