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bioRxiv · 10.1101/2022.09.26.509444

Programming super DNA-enzyme molecules for on-demand enzyme activity modulation

Zhao, H.·Xiu, X.·Li, M.·Gou, M.·Tao, L.·Zuo, X.·Fan, C.·Tian, Z.·Song, P.
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Abstract

Dynamic interactions of enzymes, including programmable configuration and cycling of enzymes, play important roles in the regulation of cellular metabolism. Here, we construct a super DNA-enzymes molecule (SDEM) that comprises at least two cascade enzymes and linked DNA strands to control and detect metabolism. We find that the programmable SDEM which comprises glucose oxidase (GOx) and horseradish peroxidase (HRP) has a 50-fold lower detection of limit and a 1.6-fold higher reaction rate than free enzymes. SDEM can be assembled and disassembled using a hairpin structure and a displacement DNA strand to complete multiple cycles. An entropically driven catalytic assembly (catassembly) enables different SDEMs to switch from SDEM with GOx and HRP cascades to SDEM with sarcosine oxidase (SOX) and HRP cascades by over six orders of magnitude less time than no catassembly to detect different metabolisms (glucose and sarcosine) on demand.

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Zhao, H., Xiu, X., Li, M., Gou, M., Tao, L., Zuo, X., Fan, C., Tian, Z., Song, P.. 2022-09-27. Programming super DNA-enzyme molecules for on-demand enzyme activity modulation. https://doi.org/10.1101/2022.09.26.509444

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