Constructing Submonolayer DNA Origami Scaffold on Gold Electrode for Wiring of Redox Enzymatic Cascade Pathways

Advances in biomimetic microelectronics offer a range of patterned assemblies of proteins and cells for in vitro metabolic engineering where coordinated biochemical pathways allow cell metabolism to be characterized and potentially controlled on a chip. To achieve these goals, developing new methods for interfacing biological systems to microelectronic devices has been in urgent demand. Here, we report the assembly of a DNA origami-templated enzymatic cascade (glucose oxidase and horseradish peroxidase) on gold electrodes, where a monolayer of DNA origami is anchored on gold electrodes via Au-S chemistry, to create programmable, electrochemically driven biomimetic device containing both biochemical and electronic components. Upon the posing of a specific electrical potential, substrates/products flow through the enzyme pair and the end product transfers electrons to the electrode. The steady state flux of the distance-dependent enzymatic cascade reactions is translated into a steady state current signal that records the overall enzyme activity. This biological system can be finely tuned by varying the distance between the enzyme pair, which opens new routes to interface microelectronic devices to biological functions.