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Cofactor Binding Dynamics Influence the Catalytic Activity and Selectivity of an Artificial Metalloenzyme.

ABSTRACT: We present an artificial metalloenzyme based on the transcriptional regulator LmrR that exhibits dynamics involving the positioning of its abiological metal cofactor. The position of the cofactor, in turn, was found to be related to the preferred catalytic reactivity, which is either the enantioselective Friedel-Crafts alkylation of indoles with ?-substituted enones or the tandem Friedel-Crafts alkylation/enantioselective protonation of indoles with ?-substituted enones. The artificial metalloenzyme could be specialized for one of these catalytic reactions introducing a single mutation in the protein. The relation between cofactor dynamics and activity and selectivity in catalysis has not been described for natural enzymes and, to date, appears to be particular for artificial metalloenzymes.

SUBMITTER: Villarino L

PROVIDER: S-EPMC7574625 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Cofactor Binding Dynamics Influence the Catalytic Activity and Selectivity of an Artificial Metalloenzyme.

Villarino Lara L Chordia Shreyans S Alonso-Cotchico Lur L Reddem Eswar E Zhou Zhi Z Thunnissen Andy Mark W H AMWH Maréchal Jean-Didier JD Roelfes Gerard G

ACS catalysis 20200918 20

We present an artificial metalloenzyme based on the transcriptional regulator LmrR that exhibits dynamics involving the positioning of its abiological metal cofactor. The position of the cofactor, in turn, was found to be related to the preferred catalytic reactivity, which is either the enantioselective Friedel-Crafts alkylation of indoles with β-substituted enones or the tandem Friedel-Crafts alkylation/enantioselective protonation of indoles with α-substituted enones. The artificial metalloen ...[more]

PMID: 33101759

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