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bioRxiv · 10.1101/2023.07.19.549658

Design of artificial molecular motor inheriting directionality and scalability.

Ito, K. I.·Sato, Y.·Toyabe, S.
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Abstract

Realizing artificial molecular motors with autonomous functionality and high performance is a major challenge in biophysics. Such motors not only provide new perspectives in biotechnology but also offer a novel approach for the bottom-up elucidation of biological molecular motors. Directionality and scalability are critical factors for practical applications. However, the simultaneous realization of both remains challenging. In this study, we propose a novel design for a rotary motor that can be fabricated using a currently available technology, DNA origami, and validate its functionality through simulations with practical parameters. We demonstrate that the motor rotates unidirectionally and processively in the direction defined by structural asymmetry, which induces kinetic asymmetry in motor motion. The motor also exhibits scalability, such that increasing the number of connections between the motor and stator allows for a larger speed, run length, and stall force. Statement of SignificanceBiological molecular motors are the most sophisticated nanomachines found in nature. Despite a long history of research, we have yet to understand how they work in detail. A simple and promising approach involves the building of artificial molecular motors. The process of achieving these goals helps us understand how the structures and mechanisms of the biological motors have been optimized through the evolution of their functions. Some artificial motors have already been achieved. However, each realization implements only a part of the characteristics of biological motors. In this work, we propose a novel motor mechanism that simultaneously implements two essential characteristics: scalability and directionality. These results will help us improve the biophysics of molecular motors and contribute to developing high-performance artificial molecular motors with possible industrial applications.

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Ito, K. I., Sato, Y., Toyabe, S.. 2023-07-19. Design of artificial molecular motor inheriting directionality and scalability.. https://doi.org/10.1101/2023.07.19.549658

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