Abstract
G-quadruplex (GQ)/hemin DNAzymes represent a class of high-activity artificial peroxidases that have been widely utilized in various redox reactions. However, the limited thermal stability of GQ/hemin systems restricts their application in high-temperature biocatalysis. Herein, we developed a thermally activated peroxidase-mimetic DNAzyme constructed by G-quadruplex nanowire (GQwire) and hemin. A remarkable temperature-enhanced activity is shown on a model reaction of 2,2'-azino-bis(3-ethylben zothiozoline-6-sulfonic acid) (ABTS) oxidation by H(2)O(2), achieving a 4.7-fold increase in catalytic activity and a 3.6-fold increase in cumulative product yield at 70 °C compared to 25°C. Structural analysis reveals that this unique thermal activation arises from the two-step thermal transition of GQwire architecture. GQwire disassembled from nanowire to oligomeric GQ rods that provides additional terminal binding sites for hemin and consequently enhancing catalytic activity at elevated temperatures. This thermal-activated DNAzyme provides an effective strategy for fabricating biocatalysts that expands their potentials in industrial manufacture.