Regioselective Arene Halogenation using the FAD‐Dependent Halogenase RebH

Together we're strong: Co-expression of the halogenase RebH with GroEL/ES and fusion of the flavin reductase RebF to MBP enabled production of both enzymes on scales sufficient for preparative regioselective oxidative halogenation of arenes. The activity and selectivity of RebH contrasts with those reported for the structurally homologous halogenase PrnA, which only enabled halogenation of nonnatural substrates at their most electronically activated positions.