A High‐Throughput in vitro Assay System for the Detection of the Enzymatic Dihydroxylation of Aliphatic Olefins

Rieske dioxygenase enzymes can perform the cis‐dihydroxylation of aliphatic olefins, representing a potential green alternative to established methods of performing this important transformation. However, the activity of the natural enzymes in this context is low relative to their more well‐known activity in the cis‐dihydroxylation of aromatics. To enable the engineering of dioxygenase enzymes for improved activity in the dihydroxylation of aliphatic olefins, we have developed an assay system to detect the relevant diol metabolites produced from whole‐cell fermentation cultures. Optimization studies were carried out to maximize the sensitivity of the assay system, and its utility in the in vitro screening of enzyme variant libraries was demonstrated. The assay system was utilized in screening studies that identified Rieske dioxygenase variants with significantly improved activity in the dihydroxylation of aliphatic olefins relative to the wild‐type enzyme.