


This article is cited by 32 publications. The rational design strategy and the easy enzymatic synthetic method presented here provide a versatile way to develop a variety of metal-responsive allosteric DNA materials, including molecular machines and logic circuits, based on metal-mediated artificial base pairing. Similarly, by incorporating a H–Cu II– H pair into an in vitro-selected Ag I-dependent DNAzyme, we have developed a DNAzyme that exhibits an AND logic-gate response to Cu II and Ag I ions. The activity of the H-modified DNAzyme was reversibly switched by the addition and removal of Cu II ions under isothermal conditions. The formation of a H–Cu II– H base pair triggers intrastrand transformation from the inactive to the active structure, enabling allosteric regulation of the DNAzyme activity in response to Cu II ions. Previously reported DNAzymes were modified by introducing a H– H pair into the stem region, and the stem-loop sequences were altered so that the structure becomes catalytically inactive in the absence of Cu II ions. We devised a new enzymatic method using a standard DNA polymerase and a ligase to prepare DNA strands containing H nucleotides.

In this study, we established a rational design strategy for developing Cu II-responsive allosteric DNAzymes by incorporating artificial hydroxypyridone ligand-type nucleotides ( H) that form a Cu II-mediated base pair ( H–Cu II– H). We expected that metal-mediated artificial base pairs, consisting of ligand-type nucleotides and a bridging metal ion, could serve as allosteric units that regulate the function of DNA molecules. Allosteric regulation is gaining increasing attention as a basis for the production of stimuli-responsive materials in many research areas including DNA nanotechnology.
