A Promiscuous De Novo Retro-Aldolase Catalyzes Asymmetric Michael Additions via Schiff Base Intermediates.
Garrabou, X., Beck, T., Hilvert, D.(2015) Angew Chem Int Ed Engl 54: 5609-5612
- PubMed: 25777153 
- DOI: https://doi.org/10.1002/anie.201500217
- Primary Citation of Related Structures:  
4PA8 - PubMed Abstract: 
Recent advances in computational design have enabled the development of primitive enzymes for a range of mechanistically distinct reactions. Here we show that the rudimentary active sites of these catalysts can give rise to useful chemical promiscuity. Specifically, RA95.5-8, designed and evolved as a retro-aldolase, also promotes asymmetric Michael additions of carbanions to unsaturated ketones with high rates and selectivities. The reactions proceed by amine catalysis, as indicated by mutagenesis and X-ray data. The inherent flexibility and tunability of this catalyst should make it a versatile platform for further optimization and/or mechanistic diversification by directed evolution.
Organizational Affiliation: 
Laboratory of Organic Chemistry, ETH Zürich, 8093 Zürich (Switzerland); Instituto de Química Avanzada de Cataluña-CSIC, Jordi Girona 18-26, 08034 Barcelona (Spain).