De Novo biosynthesis of a Nitro-Containing Amino Acid

Nitroaromatic compounds serve many purposes, and the development of metabolic pathways for their biosynthesis offers a green chemistry alternative to hazardous industrial synthesis methods. However, investigation of de novo nitro-product biosynthesis and the associated enzymes that catalyze nitro-group formation has been limited. Here, we present an integrated heterologous pathway for the production of a stable, non-toxic nitroaromatic product in Escherichia coli. Expression of four exogenous enzymes redirects metabolic flux in the shikimate pathway, including a previously uncharacterized amine oxygenase, to a nitro-containing amino acid with titers above 0.5 mM. Integration of our pathway with technology for site-specific incorporation of non-standard amino acids should enable the in situ production of nitro-containing proteins.