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Fast and Specific Assessment of the Halogenating Peroxidase Activity in Leukocyte-enriched Blood Samples
Published on: July 28, 2016
A catalysis-based selection for peroxidase antibodies with increased activity.
Jun Yin1, Jeremy H Mills, Peter G Schultz
1Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|March 12, 2004
Summary
Researchers developed a new method to evolve peroxidase antibodies. This technique uses biotin-tyramine conjugates and phage display to select for antibodies with significantly increased catalytic activity.
Area of Science:
- Biotechnology
- Enzyme Engineering
- Immunology
Background:
- Peroxidase antibodies are crucial tools in various biological assays.
- Enhancing the catalytic efficiency of antibodies is a key goal in protein engineering.
- Existing methods for antibody evolution may not directly target catalytic activity.
Purpose of the Study:
- To develop a novel selection strategy for evolving peroxidase antibodies with enhanced activity.
- To utilize a biotin-tyramine conjugate for covalent cross-linking with peroxidase antibodies.
- To identify mutations that increase the catalytic turnover (kcat/Km) of antibody 7G12 Fab.
Main Methods:
- A biotin-tyramine conjugate was synthesized and its cross-linking with peroxidase antibody 7G12 via catalytic oxidation was demonstrated.
- A phage display library of antibody 7G12 was subjected to selection based on enhanced peroxidase activity.
- Selection involved hydrogen peroxide-catalyzed oxidation of tyramine, preferential biotin labeling of active antibodies, and streptavidin-based phage capture.
Main Results:
- The developed strategy successfully selected for mutants of antibody 7G12 Fab with improved peroxidase activity.
- Mutations leading to a 10 to 20-fold increase in catalytic efficiency (kcat/Km) were identified.
- The method demonstrated the feasibility of evolving peroxidase antibodies directly based on catalytic turnover.
Conclusions:
- The biotin-tyramine conjugate-based selection strategy is effective for evolving peroxidase antibodies.
- This method allows for direct selection of antibodies with enhanced catalytic function.
- The findings pave the way for engineering improved enzymatic antibodies for diverse applications.
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