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Published on: March 25, 2020
In vitro evolution of a Friedel-Crafts deoxyribozyme
Utpal Mohan1, Ritwik Burai, Brian R McNaughton
1Department of Chemistry, Colorado State University, 200 West Lake Street, Fort Collins, CO, USA.
Organic & Biomolecular Chemistry
|February 28, 2013
Summary
Researchers developed a DNA enzyme (deoxyribozyme) that catalyzes a Friedel-Crafts reaction in water. This catalytic DNA requires copper nitrate for efficient bond formation in both cis and trans reactions.
Area of Science:
- Biochemistry
- Organic Chemistry
- Molecular Biology
Background:
- Friedel-Crafts reactions are fundamental in organic synthesis.
- Catalysis in aqueous solvents is desirable for environmental and practical reasons.
- DNA enzymes (deoxyribozymes) offer programmable catalytic capabilities.
Purpose of the Study:
- To develop a DNA enzyme capable of catalyzing a Friedel-Crafts reaction.
- To investigate the feasibility of deoxyribozyme-mediated Friedel-Crafts reactions in aqueous media.
- To explore the catalytic scope of the selected deoxyribozyme.
Main Methods:
- In vitro selection was used to isolate a 72-nucleotide single-stranded DNA enzyme.
- The deoxyribozyme's catalytic activity was tested for a Friedel-Crafts reaction between indole and acyl imidazole.
- Reaction conditions, including the necessity of copper nitrate, were investigated.
Main Results:
- A DNA enzyme was successfully selected that catalyzes a Friedel-Crafts reaction with good yield in an aqueous solvent.
- The reaction requires both the deoxyribozyme and copper nitrate for significant product formation.
- The deoxyribozyme demonstrated catalytic activity in both cis and trans Friedel-Crafts reactions.
Conclusions:
- DNA enzymes can be evolved to catalyze complex carbon-carbon bond-forming reactions like the Friedel-Crafts reaction.
- The development of deoxyribozymes for organic synthesis provides a novel, environmentally friendly catalytic approach.
- This work expands the repertoire of reactions catalyzed by engineered nucleic acids.
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