Dynamics of Metal Complex Binding in Relation to Catalytic Activity and Selectivity of an Artificial Metalloenzyme

We present an artificial metalloenzyme based on the transcriptional regulator LmrR that exhibits a unique form of structural dynamics involving the positioning of its abiological cofactor. The position of the cofactor was found to relate to the preferred catalytic activity, which is either the enantioselective Friedel-Crafts alkylation of indoles with beta-substituted indoles or the tandem Friedel-Crafts alkylation / enantioselective protonation of indoles with alpha-substituted enones. The artificial metalloenzyme could be specialized for one of these reactions by introducing a single mutation in the protein.