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Enantioselective Switch and Potential Applications in Biocatalysis
Lucia Robustini1, Francesca Paradisi2
1Dept. Chemistry, Biochemistry and Pharmaceutical Sciences. University of Bern, Freiestrasse 3, CH-3012 Bern. lucia.robustini@unibe.ch.
Chimia
|December 4, 2023
Summary
Enzymatic synthesis can achieve specific enantioselectivity by adjusting reaction conditions. A Halomonas elongata transaminase (ω-HeWT) demonstrated a switch from S- to R-enantiomer production under specific conditions.
Area of Science:
- Biocatalysis and Enzymatic Synthesis
- Stereoselective Chemical Transformations
Background:
- Enantioselectivity is crucial for enzymatic synthesis, impacting product purity and efficacy.
- Enzymes often exhibit high stereoselectivity, but some require optimization for specific enantiomers.
Purpose of the Study:
- To investigate the potential for inducing enantioselective switches in enzymes.
- To explore the manipulation of reaction conditions to alter enzymatic stereochemical outcomes.
- To highlight enzymes capable of conditional enantioselectivity and their applications.
Main Methods:
- Utilized a transaminase from Halomonas elongata (ω-HeWT) as a model enzyme.
- Systematically varied reaction parameters, including amino acceptor concentration and ionic strength.
- Analyzed the enantiomeric excess of the product under different conditions.
Main Results:
- The ω-HeWT enzyme, typically S-selective, showed a shift towards producing the R-enantiomer.
- This enantioselective switch was achieved by increasing amino acceptor concentration and ionic strength.
- Similar conditional enantioselectivity was observed in other enzyme systems.
Conclusions:
- Reaction condition tuning can successfully induce enantioselective switches in certain enzymes.
- This strategy offers a method to access both enantiomers using a single enzyme.
- The findings have implications for developing versatile biocatalytic processes.
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