Cross-linked cytochrome P450 BM3 aggregates promoted by Ru(II)-diimine complexes bearing aldehyde groups
Minh Quan Do1, Evelynn Henry1, Mallory Kato1
1San José State University, Department of Chemistry, One Washington Square, San José, CA 95192-0101, United States.
Journal of Inorganic Biochemistry
|June 12, 2018
Summary
Novel cross-linking agents improve immobilized enzyme stability and activity. Cross-linked enzyme aggregates (CLEAs) of cytochrome P450 BM3 variants show high activity recovery and enhanced stability after reduction, boosting overall protein performance.
Area of Science:
- Biocatalysis
- Protein Immobilization
- Enzyme Engineering
Background:
- Cytochrome P450 BM3 variants are crucial biocatalysts.
- Enzyme immobilization via cross-linked enzyme aggregates (CLEAs) can enhance stability and reusability.
- Traditional cross-linking agents like glutaraldehyde have limitations.
Purpose of the Study:
- To immobilize cytochrome P450 BM3 variants (F87A and 21B3) using novel cross-linking agents.
- To evaluate the efficiency of Ru(II)-diimine complexes as cross-linkers compared to traditional agents.
- To enhance the stability and activity recovery of immobilized enzymes.
Main Methods:
- Application of cross-linked enzyme aggregate (CLEA) methodology.
- Immobilization of cytochrome P450 BM3 variants (F87A and 21B3).
- Utilizing Ru(II)-diimine complexes as cross-linking agents and comparing with glutaraldehyde and dextran aldehyde.
- Reduction of imine bonds using sodium cyanoborohydride to minimize enzyme leaching.
Main Results:
- Ru(II)-diimine complexes proved effective cross-linking agents, offering modular aldehyde functionalities and a rigid framework.
- F87A CLEAs showed significant activity loss, while 21B3 CLEAs achieved up to 95% activity recovery.
- Reduced 21B3 CLEAs demonstrated sustained activity over multiple reaction rounds, yielding a 170% increase in overall protein activity compared to the free enzyme.
Conclusions:
- Ru(II)-diimine complexes are superior cross-linking agents for specific cytochrome P450 BM3 variants.
- Enzyme reduction significantly enhances CLEA stability and reusability, leading to improved biocatalytic performance.
- This immobilization strategy offers a promising approach for developing robust and efficient enzymatic systems.
Keywords:
Cross-linked enzyme aggregatesHeterogeneous biocatalysisP450 peroxygenaseRu(II)-diimine complexes with aldehydeMore Related Videos
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