Recent developments in the application of P450 based biocatalysts.

Cytochrome P450 monooxygenases (P450s) catalyze regioselective and stereoselective oxidative modifications of a wide variety of substrates, and are involved in the biosynthesis of many natural products. Despite the complex requirements of the P450 reaction system and its intransigence to recombinant expression, the promise of harnessing P450 reactivity for the industrial-scale production of specialty chemicals has led to much effort invested in P450 engineering. Here we review recent developments (between 2015 and 2017) in the application of P450s and their engineered variants as biocatalysts. We describe strategies for the reconstitution of P450 activity in heterologous microbial hosts, and the expanding repertoire of non-natural reactions catalyzed by engineered P450s.