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

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 omega-1 hydroxylation of fatty acids with quenched stepwise over-oxidation. One single mutation near the Phe catalytic tripod narrowed the heme cavity, promoting a dramatic shift toward subterminal hydroxylation with a drop in the over-oxidation activity. While crystallographic soaking experiments and molecular dynamic simulations shed light on this unique oxidation pattern, the selective biocatalyst was produced by Pichia pastoris at 0.4 g L-1 in a fed-batch bioreactor and used in the preparative synthesis of 1.4 g of (omega-1)-hydroxytetradecanoic acid with 95 % regioselectivity and 83 % ee for the S enantiomer.

Automated summary

In this study, a highly regioselective fungal peroxygenase was engineered for the omega-1 hydroxylation of fatty acids. The selective biocatalyst was produced by Pichia pastoris and successfully used for the preparative synthesis of (omega-1)-hydroxytetradecanoic acid with high regioselectivity and enantiomeric excess.