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Host-Guest Allosteric Control of an Artificial Phosphatase.

ABSTRACT: The activity of many enzymes is regulated by associative processes. To model this mechanism, we report here that the conformation of an unstructured bimetallic Zn(II) complex can be controlled by its inclusion in the cavity of a γ-cyclodextrin. This results in the formation of a catalytic bimetallic site for the hydrolytic cleavage of the RNA model substrate HPNP, whose reactivity is 30-fold larger with respect to the unstructured complex. Competitive inhibition with 1-adamantanecarboxylate displaces the metal complex from the cyclodextrin decreasing the reactivity.

SUBMITTER: Czescik J

PROVIDER: S-EPMC7997383 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Host-Guest Allosteric Control of an Artificial Phosphatase.

Czescik Joanna J Lyu Yanchao Y Neuberg Samuele S Scrimin Paolo P Mancin Fabrizio F

Journal of the American Chemical Society 20200406 15

The activity of many enzymes is regulated by associative processes. To model this mechanism, we report here that the conformation of an unstructured bimetallic Zn(II) complex can be controlled by its inclusion in the cavity of a γ-cyclodextrin. This results in the formation of a catalytic bimetallic site for the hydrolytic cleavage of the RNA model substrate HPNP, whose reactivity is 30-fold larger with respect to the unstructured complex. Competitive inhibition with 1-adamantanecarboxylate disp ...[more]

PMID: 32212681

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