Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 4

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Novel galactonic acid-binding hexameric lectin from Hibiscus mutabilis seeds with antiproliferative and potent HIV-1 reverse transcriptase inhibitory activities

100%
Lam S., Ng T.
|
|
issue 4
649-654
EN
A hexameric 150-kDa lectin was isolated from dried Hibiscus mutabilis seeds using a chromatographic protocol that involved ion exchange chromatography on SP-Sepharose, and gel filtration on Superdex 75 and Superdex 200. The lectin was not adsorbed on SP-Sepharose and was eluted from the Superdex 75 column in the void volume. It was eluted in the first peak from Superdex 200. It was strongly adsorbed on DEAE-cellulose and Q-Sepharose and could not be easily desorbed. The hemagglutinating activity of the lectin, which was stable at pH 4-7 and up to 50°C, could be inhibited by 25 mM galactonic acid. This is the first report of a galactonic acid-binding lectin. It potently inhibited HIV-1 reverse transcriptase with an IC50 of 0.2 µM. It exhibited weak antiproliferative activity towards both hepatoma HepG2 cells (40% inhibition) and breast cancer MCF-7 cells (50% inhibition) at 100 µM concentration of the lectin. It did not inhibit mycelial growth of a number of fungi tested.
2
Content available remote

Purification and characterization of an antibacterial protein from dried fruiting bodies of the wild mushroom Clitocybe sinopica

71%
Zheng S., Liu Q., Zhang G., Wang H., Ng T.
|
2010
|
vol. 57
|
issue 1
43-48
EN
A novel antibacterial protein with a molecular mass of 44 kDa has been isolated from dried fruiting bodies of the wild mushroom Clitocybe sinopica. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis showed that the protein was composed of two subunits each with a molecular mass of 22 kDa. Its N-terminal amino-acid sequence, SVQATVNGDKML, has not been reported for other antimicrobial proteins. The purification protocol included ion exchange chromatography on DEAE-cellulose, CM-cellulose and Q-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The antibacterial protein was adsorbed on all three ion exchangers. The antimicrobial activity profile of the protein against tested bacterial and fungal strains disclosed that it possessed potent antibacterial activity against Agrobacterium rhizogenes, A. tumefaciens, A. vitis, Xanthomonas oryzae and X. malvacearum with a minimum inhibitory concentration mostly below 0.6 µM. However, it had no antibacterial activity against Pseudomonas batatae, Erwinia herbicola, Escherichia coli, and Staphylococcus aureus, and no antifungal activity against Setosphaeria turcica, Fusarium oxysporum, Verticillium dahliae, Bipolaris maydis, and B. sativum. The antibacterial antivity against A. tumefaciens was stable after exposure to 20-60°C for 30 min and to pH 4-9 for 1h.
3
Publication available in full text mode
Content available

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

61%
Zhang W., Du F., Tian G., Zhao Y., Wang H., Ng T.
|
2018
|
vol. 65
|
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.
4
Publication available in full text mode
Content available

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

61%
Geng X., Te R., Tian G., Zhao Y., Zhao L., Wang H., Ng T.
|
2017
|
vol. 64
|
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.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.