Laboratory evolution of stereoselective enzymes as a means to expand the toolbox of organic chemists

This is a personal account of the author's research in the area of directed evolution of the past 15 years. It focuses on a novel concept first reported in 1997, which has proven to be useful in the development of catalysts for asymmetric transformations in synthetic organic chemistry. When performing such reactions, organic chemists can choose between synthetic transition metal catalysts, organocatalysts or enzymes. However, the latter suffer from traditional disadvantages, such as the often observed insufficient stereoselectivity, limited substrate scope and/or rate. The concept of laboratory evolution of stereoselective mutant enzymes eliminates these long-standing limitations and therefore extends the toolbox of synthetic organic chemistry.