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Refolding of laccase in dilution additive mode with copper-based ionic liquid
Sang-Woo Bae1, Kihun Ahn, Yoon-Mo Koo
1Department of Biological Engineering, Inha University, Incheon, 402-751, Republic of Korea.
Applied Biochemistry and Biotechnology
|August 27, 2013
Summary
A novel copper-based ionic liquid ([EMIM][CuCl₃]) significantly enhances laccase refolding by over 2.7 times. This ionic liquid specifically aids copper-containing proteins, unlike non-copper proteins like lysozyme.
Area of Science:
- Biochemistry
- Materials Science
- Protein Engineering
Background:
- Ionic liquids (ILs) are tunable molten salts with diverse applications.
- Protein refolding is crucial for enzyme activity but often challenging.
- Copper is an essential cofactor for some enzymes, including laccase.
Purpose of the Study:
- To investigate the efficacy of a copper-based ionic liquid in improving protein refolding.
- To determine the optimal conditions for using this ionic liquid in protein refolding.
- To assess the specificity of the ionic liquid's effect on copper-containing proteins.
Main Methods:
- Utilized 1-ethyl-3-methylimidazolium trichlorocuprate ([EMIM][CuCl₃]) as a refolding agent for laccase from Trametes versicolor.
- Compared refolding yields with conventional urea-based buffers.
- Evaluated refolding efficiency at various temperatures (4, 25, and 37 °C).
- Tested the ionic liquid's effect on lysozyme, a non-copper-containing protein.
Main Results:
- The copper-based ionic liquid ([EMIM][CuCl₃]) improved laccase refolding yield by more than 2.7 times compared to urea.
- Optimal refolding temperature for laccase using this ionic liquid was found to be 25 °C.
- The ionic liquid did not enhance the refolding of lysozyme, indicating specificity.
Conclusions:
- Copper-based ionic liquids, specifically [EMIM][CuCl₃], are highly effective in enhancing the refolding of copper-containing proteins like laccase.
- The observed enhancement is attributed to the presence of copper within the ionic liquid.
- [EMIM][CuCl₃] offers a promising alternative to conventional refolding agents for specific metalloproteins.
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