Engineering a Highly Regioselective Fungal Peroxygenase for the Synthesis of Hydroxy Fatty Acids (Póster)

Abstract

The hydroxylation of fatty acids is an appealing reaction in synthetic chemistry, although the lack of selective catalysts hampers its industrial implementation. In this study, we have engineered a highly regioselective fungal peroxygenase for the ¿-1 hydroxylation of fatty acids with quenched stepwise over-oxidation. One single mutation (A77L, Fett variant) found by structural studies and saturation mutagenesis near the Phe catalytic tripod narrowed the heme cavity, promoting a dramatic shift toward subterminal hydroxylation with a drop in the over-oxidation activity as determined by GC/MS. While molecular dynamic simulations shed light on this unique oxidation pattern, the selective biocatalyst was overexpressed in Pichia pastoris at 0.4 g/L-1 operating a fed-batch bioreactor and used for the preparative synthesis of 1.4 g of (¿-1)-hydroxytetradecanoic acid with 95% regioselectivity and 83% ee for the S-enantiomer.