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Chromatographic Media (chromatographic + media)
Selected AbstractsPurification of Angularin, A Novel Antifungal Peptide from Adzuki BeansJOURNAL OF PEPTIDE SCIENCE, Issue 3 2002Dr X. Y. Ye Abstract An antifungal peptide was isolated from the adzuki bean with a procedure involving affinity chromatography on Affi-gel blue gel and ion exchange chromatography on CM-Sepharose. The protein designated angularin was adsorbed on both types of chromatographic media and possessed a molecular weight of 8 kDa. Angularin exhibited antifungal activity against a variety of fungal species including Mycospharella arachidiocola and Botrytis cinerea. It inhibited mycelial growth in B. cinerea with an IC50 of 14.3 µM. Fusarium oxysporum and Rhizoctonia solani were not inhibited. Angularin demonstrated inhibitory activity on translation in the rabbit reticulocyte lysate system (IC50 = 8.0 µM) but did not affect proliferation of splenocytes. The activity of HIV-1 reverse transcriptase was inhibited in the presence of angularin. Its N -terminal sequence was GEPGQKE. Copyright © 2002 European Peptide Society and John Wiley & Sons, Ltd. [source] Characterisation of a haemagglutinin from Hokkaido red bean (Phaseolus vulgaris cv. Hokkaido red bean)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2010Jack H Wong Abstract BACKGROUND: A haemagglutinin was purified from Japanese Hokkaido red beans (Phaseolus vulgaris cv. Hokkaido red bean) with a procedure that included three chromatographic media. RESULTS: Haemagglutinating activity was adsorbed on DEAE cellulose, Affi-gel blue gel and Mono S. The pure haemagglutinin was a homodimer and each subunit was around 30 kDa in molecular mass. The haemagglutinating activity of this agglutinin could not be inhibited by a variety of simple sugars at 200 mmol L,1 concentration including ,- L -fucose, D(+)-galactose, D(+)-glucose, D(+)-glucosamine, D(,)galactosamine, galacturonic acid, (+)-lactose, D(+)-melibose, L(,)-mannose, D(+)-mannose, D -mannosamine, D(+)-raffinose, L -rhamnose, (+)-xylose and galacturonic acid. The haemagglutinating activity was fully retained at pH 4,11 and at 0,80 °C, but was completely lost at extreme pH values (0,2 and 13,14) and at very high temperatures (90 °C and 100 °C). The haemagglutinin exhibited a weak mitogenic activity toward mouse splenocytes, a stronger anti-proliferative activity than Con A toward HepG2 (human hepatoma) cells and inhibited >80% of HIV-1 reverse transcriptase inhibitory activity at 3.3 µmol L,1. It was devoid of anti-fungal activity. CONCLUSION: Hokkaido red bean haemagglutinin possesses a potent anti-proliferative effect on HepG2 cells. Copyright © 2009 Society of Chemical Industry [source] Serum biomarker profiling by solid-phase extraction with particle-embedded micro tips and matrix-assisted laser desorption/ionization mass spectrometry,RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 7 2008Arti Navare One of the main challenges in high-throughput serum profiling by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is the development of proteome fractionation approaches that allow the acquisition of reproducible profiles with a maximum number of spectral features and minimum interferences from biological matrices. This study evaluates a new class of solid-phase extraction (SPE) pipette tips embedded with different chromatographic media for fractionation of model protein digests and serum samples. The materials embedded include strong anion exchange (SAX), weak cation exchange (WCX), C18, C8, C4, immobilized metal affinity chromatography (IMAC) and zirconium dioxide particles. Simple and rapid serum proteome profiling protocols based on these SPE micro tips are described and tested using a variety of MALDI matrices. We show that different types of particle-embedded SPE micro tips provide complementary information in terms of the spectral features detected for , -casein digests and control human serum samples. The effect of different sample pretreatments, such as serum dilution and ultrafiltration using molecular weight cut-off membranes, and the reproducibility observed for replicate experiments, are also evaluated. The results demonstrate the usefulness of these simple SPE tips combined with offline MALDI-TOF MS for obtaining information-rich serum profiles, resulting in a robust, versatile and reproducible open-source platform for serum biomarker discovery. Copyright © 2008 John Wiley & Sons, Ltd. [source] Protein instability during HIC: Hydrogen exchange labeling analysis and a framework for describing mobile and stationary phase effectsBIOTECHNOLOGY & BIOENGINEERING, Issue 1 2007Yunzhi Xiao Abstract Unfolding of marginally stable proteins is a significant factor in commercial application of hydrophobic interaction chromatography (HIC). In this work, hydrogen-deuterium isotope exchange labeling has been used to monitor protein unfolding on HIC media for different stationary phase hydrophobicities and as a function of ammonium sulfate concentration. Circular dichroism and Raman spectroscopy were also used to characterize the structural perturbations experienced by solution phase protein that had been exposed to media and by protein adsorbed on media. As expected, greater instability is seen on chromatographic media with greater apparent hydrophobicity. However, increased salt concentrations also led to more unfolding, despite the well-known stabilizing effect of ammonium sulfate in solution. A thermodynamic framework is proposed to account for the effects of salt on both adsorption and stability during hydrophobic chromatography. Using appropriate estimates of input quantities, analysis with the framework can explain how salt effects on stability in chromatographic systems may contrast with solution stability. Biotechnol. Bioeng. 2007;96: 80,93. © 2006 Wiley Periodicals, Inc. [source] | ||||||||||