Mechanosensing Potentials Gate Fuel Consumption in a Bipedal DNA Nanowalker

Abstract

The molecular machines known as DNA nanowalkers turn fuel into motion with unrivaled efficiency, serving as artificial parallels to naturally evolved motor proteins, but their study is hampered by a lack of quantitative, experimentally useful models. Using three-dimensional molecular modeling, the authors visualize the ability of a nanowalker's foot to accept or reject a fuel molecule, based on whether it is pulled forward or backward respectively. This lets a two-footed nanowalker step forward instead of backward along a suitable track, despite its feet being chemically identical. Optimization predicts that the shorter this nanowalker's body is, the more efficient it will be.