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Updated: May 20, 2026
08:56
Synthesis of 1,2-Azaborines and the Preparation of Their Protein Complexes with T4 Lysozyme Mutants
Published on: March 25, 2017
Interaction mechanism between berberine and the enzyme lysozyme
Ling-Li Cheng1, Mei Wang, Ming-Hong Wu
1Shanghai Applied Radiation Institute, Shanghai University, Shanghai 200444, China.
Summary
Berberine (BBR) interacts with lysozyme (Lys) via hydrophobic binding, forming a complex. Under photoexcitation, BBR selectively oxidizes tryptophan residues in lysozyme through electron transfer, relevant for photodynamic therapy.
Area of Science:
- Biochemistry
- Photodynamic Therapy
- Spectroscopy
Background:
- Lysozyme (Lys) is a model protein.
- Berberine (BBR) is an antitumorigenic compound.
- Investigating BBR-protein interactions is crucial for developing novel photosensitizers.
Purpose of the Study:
- To investigate the interaction between lysozyme and berberine.
- To explore the potential of BBR as a photosensitizer in photodynamic therapy.
- To elucidate the mechanism of BBR-Lys interaction under photoexcitation.
Main Methods:
- Spectroscopic methods (fluorescence spectroscopy).
- Laser flash photolysis.
- Thermodynamic calculations.
Main Results:
- BBR binds to Lys at one site via hydrophobic interactions, causing changes in tryptophan residue environment.
- Static quenching is the primary fluorescence quenching mechanism.
- BBR neutral radicals react with tryptophan residues via electron transfer, forming radical cations and neutral radicals.
- BBR selectively oxidizes tryptophan residues in Lys.
Conclusions:
- BBR forms a complex with Lys through hydrophobic interactions.
- The interaction mechanism involves electron transfer, particularly the oxidation of tryptophan residues by BBR radicals.
- Findings support BBR's potential as a photosensitizer for photodynamic therapy.
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