The EcDERA L20A and F76A variants showed significant improvement over both EcDERAWT and FSAWT. For both variants, conversions ranging from 34-91% were obtained towards all substrates screened with the exception of O-TBDMS which showed no activity towards any of the enzyme variants. For the majority of substrates EcDERAF76A gave higher conversion than EcDERAL20A. The double alanine mutation at these two positions EcDERAL20A/F76A showed increased conversion with some of the larger aldehyde substrates (MOE, OBn, heptanal) at the cost of decreased conversion with a selection of other functional groups (OH, Cl, OMe).