Fluorescence study of laccase from Trametes versicolor under the effects of pH, chemical denaturants and ionic liquids
| Autor: | O. Saoudi, N. Ghaouar, Tahar Othman |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Analytical chemistry 02 engineering and technology 03 medical and health sciences chemistry.chemical_compound Materials Chemistry Formate Physical and Theoretical Chemistry Spectroscopy Trametes versicolor Laccase Chromatography Aqueous solution biology Tryptophan 021001 nanoscience & nanotechnology Condensed Matter Physics biology.organism_classification Fluorescence Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials 030104 developmental biology chemistry Ionic liquid Urea 0210 nano-technology |
| Zdroj: | Journal of Molecular Liquids. 225:56-63 |
| ISSN: | 0167-7322 |
| DOI: | 10.1016/j.molliq.2016.11.050 |
| Popis: | Herein, we have studied the fluorescence emissions for the laccase from Trametes versicolor in aqueous solutions for various pH, chemical denaturants and ionic liquids (ILs). The fluorescence spectra were recorded from 310 to 450 nm after exciting the Tryptophan (Trp) at 280 nm. We have shown that the fluorescence intensity reaches its maximum around pH = 4 whereas the excitation for pH 7 causes a red shift. The influence of the superficial charges distribution on the fluorescence emission was also investigated. The effects of Pyrrolidinuim Formate ([pyrr][F]) and Morphilinium Formate ([morph][F]) ILs on the laccase fluorescence emissions for various volumetric fractions was studied. From the variation of the maximum wavelength, λmax, versus the volumetric fractions, we have determined the midpoint concentration C1/2 which are equals to 42.62% and 40.91% for [pyrr][F] and [morph][F], respectively. For urea and GdmCl chemical denaturants, we have shown that the fluorescence intensity decreases with increasing denaturants concentration. We have also used the linear regression model to determine the energy of unfolding, ∆ GD. The midpoint concentrations for urea and GdmCl denaturants which are around 3.06 and 3.17 M respectively are determined. |
| Databáze: | OpenAIRE |
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