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The noncovalent dimerization of a G-quadruplex/hemin DNAzyme improves its biocatalytic properties.

ABSTRACT: While many protein enzymes exert their functions through multimerization, which improves both selectivity and activity, this has not yet been demonstrated for other naturally occurring catalysts. Here, we report a multimerization effect applied to catalytic DNAs (or DNAzymes) and demonstrate that the enzymatic efficiency of G-quadruplexes (GQs) in interaction with the hemin cofactor is remarkably enhanced by homodimerization. The resulting non-covalent dimeric GQ-DNAzyme system provides hemin with a structurally defined active site in which both the cofactor (hemin) and the oxidant (H₂O₂) are activated. This new biocatalytic system efficiently performs peroxidase- and peroxygenase-type biotransformations of a broad range of substrates, thus providing new perspectives for biotechnological application of GQs.

SUBMITTER: Cheng Y

PROVIDER: S-EPMC8163442 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Zippered G-quadruplex/hemin DNAzyme: exceptional catalyst for universal bioanalytical applications.

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