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bioRxiv · 10.64898/2026.02.17.706383

High-Performance, Computer-Controlled Bipedal DNA Motor

Basak, S.·Berger, Y.·Perel, O.·Shapira, H.·Tomov, T. E.·Sheheade, B.·Tsukanov, R.·Uralevitch, M.·Nir, E.
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Abstract

Achieving precise, repeatable motion at the molecular scale remains a central challenge in the development of synthetic molecular machines. Here we report a high-fidelity, fast bipedal DNA walker that moves bidirectionally along a DNA origami track using a fuel-before-antifuel operational scheme that suppresses trap states typical of externally powered DNA motors. Automated, computer-controlled microfluidics enables programmable trajectory execution with >98% yield per step and sustained bidirectional walking over distances of up to 360 nm, as monitored by single-molecule FRET. Kinetic analysis reveals rapid leg lifting but slower leg placement due to inhibitory fuel-antifuel heterocomplex formation, identifying a mechanistic bottleneck that can be mitigated through optimization of fuel, antifuel and foothold design. The resulting motor operates with efficiencies of up to 4 orders of magnitude higher than previous externally controlled DNA walkers, establishing a robust framework for deterministic, programmable molecular transport.

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Basak, S., Berger, Y., Perel, O., Shapira, H., Tomov, T. E., Sheheade, B., Tsukanov, R., Uralevitch, M., Nir, E.. 2026-02-18. High-Performance, Computer-Controlled Bipedal DNA Motor. https://doi.org/10.64898/2026.02.17.706383

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