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Updated: May 10, 2026
08:59
Defining Substrate Specificities for Lipase and Phospholipase Candidates
Published on: November 23, 2016
Optimization of a small laccase by active-site redesign
Miguel D Toscano1, Leonardo De Maria, Sune Lobedanz
1Department of Protein Diversity, Novozymes A/S, Krogshoejvej 36, 2880 Bagsvaerd, Denmark. mdto@novozymes.com
Chembiochem : a European Journal of Chemical Biology
|June 19, 2013
Summary
Engineered small laccase from Streptomyces coelicolor (SLAC) exhibits significantly enhanced activity on industrial substrates. This protein engineering breakthrough offers a faster, more efficient biocatalyst for various applications.
Area of Science:
- Enzyme engineering
- Biocatalysis
- Protein structure-function relationships
Background:
- Laccases are multi-copper oxidases with broad substrate specificity.
- Streptomyces coelicolor small laccase (SLAC) is a potential biocatalyst but requires optimization for industrial use.
- Enhancing enzyme efficiency on specific substrates is crucial for biocatalytic applications.
Purpose of the Study:
- To engineer a small laccase from Streptomyces coelicolor (SLAC) for improved activity on commercially relevant substrates.
- To investigate the impact of structure-based design and site-directed mutagenesis on SLAC's catalytic efficiency.
- To broaden the substrate scope and mediator usability of engineered SLAC variants.
Main Methods:
- Structure-based design of SLAC variants.
- Site-directed mutagenesis to introduce specific amino acid changes.
- Enzyme activity assays using commercially relevant substrates and mediators.
- Characterization of kinetic parameters and redox potential compatibility.
Main Results:
- Engineered SLAC variants demonstrated up to a 40-fold increase in efficiency on 2,6-dimethoxyphenol.
- Variants exhibited enhanced ability to utilize mediators with higher redox potentials, including methylsyringate and TEMPO.
- Successful application of structure-based design and mutagenesis to enhance laccase performance.
Conclusions:
- Protein engineering strategies can significantly improve the performance of small laccases like SLAC.
- The engineered SLAC variants are more efficient and versatile biocatalysts for industrial applications.
- This work provides a foundation for developing tailored laccases for specific biotechnological needs.
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