Nanoscale Molecular Transport by Synthetic DNA Machines

Biological systems have evolved motor proteins programmed to perform intracellular transport powered by ATP hydrolysis [23, 14]. Striding along a microtubule with a hand-over-hand gait and a step size of ≈8 nm [26], kinesin is capable of taking ≈100 steps per second, typically negotiating ≈100 steps before falling off the microtubule [4]. Replicating these performance characteristics with a synthetic mimic presents a daunting challenge to molecular engineers pursuing programmable active transport as a means to assembling or probing nanoscale systems.