The bakers' yeast reduction of ß-keto nitriles has been difficult to achieve due to a dominant alkylating mechanism. A library of 18 bakers' yeast reductases, that are overexpressed in E. coli, were used to screen a variety of these compounds. In some cases, both antipodes of the corresponding alcohol could be isolated with a high e.e. In addition, the E. coli whole-cell system can be optimized to nearly eliminate the competing alkylating mechanism. This strategy affords a scaleable process towards asymmetric ß-hydroxy alcohols.