Engineers Synthesize DNA Material with Artificial Metabolism
Engineers and scientists at Cornell University have constructed a DNA material displaying capabilities for metabolism, self-assembly, and organization which are three key traits of life. This material, while not alive in and of itself, shows the potential for creating more lifelike machines and even robots, utilizing artificial metabolism to better emulate living organisms.
The team, headed by professor of biological and environmental engineering Dan Luo and research associate Shogo Hamada, published a paper entitled “Dynamic DNA material with emergent locomotion behavior powered by artificial metabolism” in the Science Robotics journal. Luo characterizes their work as “not making something that’s alive, but [...] creating materials that are much more lifelike than have ever been seen before.”
As detailed in their paper, the researchers used a method called DASH (DNA-based Assembly and Synthesis of Hierarchical materials) to create the material. In the paper, this is described as a “mesoscale approach to create dynamic materials from biomolecular building blocks using artificial metabolism.” To break that down, this method, in effect, imitates the metabolic processes seen in living creatures. Both anabolism and catabolism are emulated.
From a base sequence, a chain of DNA capable of perpetuating the cycle of growth and decay inherent to living organisms can be synthesized. This allows for a form of movement as the material “grows” towards a destination while “decaying” away from its origin, in addition to other lifelike features. Currently, DASH can be applied on the mesoscale level (between 0.1mm and 5mm in size) and smaller.
DASH relies on the properties of DNA itself in order to create artificial material. Deoxyribonucleic Acid (DNA) is a polymer - a large molecule composed of a number of repeated sub-units known as monomers which are, in the case of DNA, nucleotides. The nature of DNA as a “chain” of repeated parts lends itself to the DASH method, as the material can be “synthesized and assembled into precoded patterns via anabolism,” much like DNA is in nature. Furthermore, nucleotides themselves carry the chemical energy (in the form of “packet” molecules known as nucleoside triphosphates) which is used by multiple cellular functions.
The technology’s implications appear to be profound. Hamada believes that “artificial metabolism could open a new frontier in robotics” with further application, seeing as a relatively simple design such as the one employed in this trial could engage in sophisticated behaviors such as racing. The key is that artificial metabolism can be programmed into the DNA material in order to achieve a specific goal. For example, the material can be used as a kind of biological sensor, seeking out or avoiding certain stimuli, which has medical as well as biochemical applications, such as detecting the presence of a certain pathogen.
While the material as it currently stands can only last for two cycles of generation and degeneration before expiring, increasing its longevity opens up a number of possible applications for DASH. As Hamada notes, “lifelike self-reproducing machines” would become feasible given adjustments to the material’s metabolic processes, facilitating its use in longer-term solutions. Luo is even more ambitious, believing “the use of DNA gives the whole system a self-evolutionary possibility,” with the material able to self-adjust in a matter of seconds to account for changes in the environment around it. As Luo states, “That is huge.”