Asymmetric enzymatic hydrophosphorylation through O2 activation.

Enzymatic carbon-phosphorus bond formation is extremely rare in nature, limiting biocatalytic access to phosphorus-containing compounds that are widely used in pharmaceuticals and agrochemicals. Here, we report an asymmetric enzymatic hydrophosphorylation through oxygen activation using a repurposed flavin-dependent enzyme. Mechanistic studies revealed that reactive oxygen species are converted into productive phosphorus-centered radicals, followed by radical addition and enzymatic hydrogen atom transfer, achieving high enantioselectivity. The enzyme accommodates diverse phosphorus-hydrogen donors that pose challenges to chemical catalysis, enabling the biosynthesis of valuable phosphorus-containing scaffolds. This work expands the scope of biocatalysis to programmable carbon-phosphorus bond formation and establishes a paradigm for channeling oxygen reactivity in enzymes.