Tumbleweed stands with two of its three feet attached to a DNA strand, with each foot binding to a specific DNA sequence. By adding or removing molecules that control which feet can bind, the protein motor can be guided on a walk along the DNA strand.
Illustration Credit: Courtesy of the research group
Scientific Frontline: Extended "At a Glance" Summary: Artificial Protein Motor "Tumbleweed"
The Core Concept: An international research team has engineered "Tumbleweed," an artificial protein motor capable of taking externally controlled, directed steps along a DNA track to mimic the biological engines found inside living cells.
Key Distinction/Mechanism: Unlike previous molecular machines constructed from synthetic molecules or DNA, or static AI-designed proteins, Tumbleweed is built entirely from complex protein components. It navigates by alternating three distinct "feet" that bind to specific DNA sequences; researchers direct its movement by modifying the surrounding chemical environment to control which feet attach to the track..
Major Frameworks/Components:
- Tumbleweed Protein Motor: A dynamic, engineered protein structure featuring three distinct binding appendages, or "feet."
- DNA Track: A structured nucleic acid pathway containing specific sequences that correspond to the motor's feet.
- Chemical Environment Control: A mechanism where the addition or removal of specific molecules triggers the binding and unbinding of the feet, forcing the motor to take a step.
- Biological Analogs: Modeled after naturally occurring motor proteins such as myosin, which powers muscle contraction and cell division, and kinesin, which transports intracellular signaling molecules.
Branch of Science: Synthetic Biology, Nanophysics, Molecular Biology, and Biochemistry.
Future Application: Researchers aim to develop autonomous artificial proteins capable of navigating independently using chemical fuel, which could eventually yield advanced intracellular transport systems, targeted drug delivery mechanisms, and scalable biomolecular machines.
Why It Matters: Because proteins are life's primary building blocks, they offer greater complexity, scalability, and refinement potential than other synthetic molecules. Transitioning from statically designed proteins to dynamic, controllable motors represents a fundamental breakthrough in understanding and replicating biological mechanics.
The most advanced engines are not found in airplanes, cars, or other machines—they are found in nature. Inside our cells, tiny protein motors power everything from cell division to muscle movement with an efficiency and precision that have fascinated researchers for decades and inspired long-standing efforts to replicate them. Now, scientists have taken an important first step.
An international research team led by Lund University and the University of New South Wales has created an artificial protein motor that can be controlled to take directed steps along a DNA track—a long-standing goal in synthetic biology.
Nature’s protein motors carry out some of the most sophisticated mechanical tasks in the body with great precision and efficiency. Understanding and recreating how these biological motors achieve their remarkable performance has therefore been a major scientific challenge.
The new findings, published in Nature Nanotechnology, show that it is possible to build artificial protein motors using the same building blocks as biological ones.
“Just as the steam engine laid the foundation for today’s mechanical engines, this breakthrough could mark the starting point for a deeper understanding of biology’s own motors,” says Heiner Linke, professor of nanophysics at Lund University and lead author of the study.
A Molecular Walk Along DNA
The protein motor, named Tumbleweed, moves by alternating between three “feet” that bind to specific DNA sequences. By changing the surrounding chemical environment, the researchers can control both when the motor takes a step and the direction in which it moves.
“With Tumbleweed, we are gaining insight into the fundamental principles governing biological protein motors and how we may eventually come closer to matching nature’s performance,” says Heiner Linke.
Tumbleweed stands with two of its three feet attached to a DNA strand, with each foot binding to a specific DNA sequence. By adding or removing molecules that control which feet can bind, the protein motor can be guided on a walk along the DNA strand. (Illustration: from the research group)
Nature’s protein motors perform some of life’s most advanced mechanical tasks. Linke explains that the motor protein myosin converts chemical energy into muscle force and plays an essential role in cell division, while kinesin transports signaling molecules within cells.
“Proteins are far more complex than other molecular building blocks and therefore offer much greater possibilities. But that same complexity also makes them more challenging to work with,” he says.
From Learning to Walk to Running a Marathon
The ability to design entirely new proteins has advanced rapidly in recent years, but most efforts have focused on creating individual, static structures. With Tumbleweed, the researchers demonstrate that it is possible to create dynamic, moving structures that can be externally controlled.
For the researchers, Tumbleweed is only the beginning. Their next goal is to develop artificial proteins that no longer require external control but can “walk” independently using chemical fuel.
Linke compares the progress to a child learning to walk:
“Right now, we have a one-year-old who can take a few steps while holding someone’s hand. The next stage is learning to walk independently. After that, we can start thinking about athletics, marathons, and the Olympics,” he concludes.
Reference material: What Is: Synthetic Biology
Published in journal: Nature Nanotechnology
Title: Clocked stepping of an artificial protein walker along a DNA track
Authors: Patrik Nilsson, Neil O. Robertson, Nils Gustafsson, Roberta B. Davies, Chu Wai Liew, Aaron Lyons, Ralf Eichhorn, Cassandra S. Niman, Gerhard A. Blab, Elizabeth H. C. Bromley, Andrew E. Whitten, Anthony P. Duff, Ivan N. Unksov, Jason P. Beech, Peter Jönsson, Till Böcking, Birte Höcker, Derek N. Woolfson, Nancy R. Forde, Heiner Linke, and Paul M. G. Curmi
Source/Credit: Lund University | Jessika Sellergren
Edited by: Scientific Frontline
Reference Number: sybi070726_01