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Enzymatic activity regulated by a surfactant and hydroxypropyl β-cyclodextrin
Qingzhong Li1, Tao Zhai, Kun Du
1Beijing Key Lab of Bioprocess, Department of Biochemical Engineering, Beijing University of Chemical Technology, Beijing, China.
Colloids and Surfaces. B, Biointerfaces
|September 10, 2013
Summary
Sodium dodecyl benzene sulfonate (SDBS) prevents lysozyme aggregation at low concentrations but causes structural changes at high concentrations, inhibiting its activity. Hydroxypropyl β-cyclodextrin (HP-β-CD) fully restores enzyme function.
Area of Science:
- Biochemistry
- Protein Chemistry
- Biophysical Chemistry
Background:
- Lysozyme is a key enzyme in biological systems.
- Understanding protein-surfactant interactions is crucial for biochemical applications.
- Sodium dodecyl benzene sulfonate (SDBS) is a common anionic surfactant.
Purpose of the Study:
- To investigate the effect of SDBS on lysozyme structure, aggregation, and enzymatic activity.
- To elucidate the interaction mechanism between SDBS and lysozyme.
- To explore methods for reversing SDBS-induced enzyme inactivation.
Main Methods:
- Circular dichroism (CD) spectroscopy to assess protein structure and aggregation.
- Fluorescence and UV-Vis spectroscopy to probe microenvironmental changes.
- Two-dimensional Fourier-transform infrared (2D-FTIR) spectroscopy to analyze secondary structures.
- Enzyme activity assays to quantify lysozyme function.
Main Results:
- SDBS prevents lysozyme aggregation at low concentrations.
- High SDBS concentrations induce conformational and structural changes in lysozyme.
- SDBS inhibits lysozyme enzymatic activity in a dose-dependent manner.
- Spectroscopic analyses revealed microenvironmental changes around the active site.
- Hydroxypropyl β-cyclodextrin (HP-β-CD) successfully detached SDBS, restoring enzyme activity.
Conclusions:
- SDBS exhibits concentration-dependent effects on lysozyme structure and function.
- The interaction mechanism involves microenvironmental and structural modifications.
- Enzymatic activity of lysozyme can be modulated by SDBS and HP-β-CD.
- HP-β-CD offers a viable strategy for enzyme activity recovery.
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