Interfacing microbial styrene production with a biocompatible cyclopropanation reaction.

The introduction of new reactivity into living organisms is a major challenge in synthetic biology. Despite an increasing interest in both the development of small-molecule catalysts that are compatible with aqueous media and the engineering of enzymes to perform new chemistry in vitro, the integration of non-native reactivity into metabolic pathways for small-molecule production has been underexplored. Herein we report a biocompatible iron(III) phthalocyanine catalyst capable of efficient olefin cyclopropanation in the presence of a living microorganism. By interfacing this catalyst with E. coli engineered to produce styrene, we synthesized non-natural phenyl cyclopropanes directly from D-glucose in single-vessel fermentations. This process is the first example of the combination of nonbiological carbene-transfer reactivity with cellular metabolism for small-molecule production.