Living Components

The lifetime of programmable structural dynamics can be infinitely varied in this DNA-based system. Photo: AG Walther

Cells assemble dynamically: their components are continuously exchanging and being replaced. This enables the structures to adapt easily to different situations, and by rearranging the components to respond to stimuli faster, to renew or to form just on demand.

The microtubules, a scaffold structure made of protein fibers that can be found in the cytoplasm of the cells of algae, plants, fungi, animals and humans, are one such dynamic mesh.

Because of their self-organizing structure, these fibers constantly form and degrade at the same time, thereby actively supporting the cell in complex tasks such as cell division or locomotion. The fibers require energy to form and maintain such dynamic states.

Now, for the first time, Prof. Dr. Andreas Walther and Dr. Laura Heinen from the Institute for Macromolecular Chemistry and the Center of Interactive Materials and Bioinspired Technologies (FIT) at the University of Freiburg have succeeded in programming the dynamics of such dissipative, i.e. energy-consuming, structures in an artificial chemical system on the basis of DNA components. The researchers present their results in the latest edition of the journal Science Advances.

The difficulty of programmable structural dynamics in synthetic dissipative systems is the synchronization of the energetic deactivation and activation with the structural build-up and degradation of the components.

The Freiburg researchers were able to solve the problem by using an energy-driven, dynamic covalent bond, that is responsible for the firm cohesion of atoms, in the backbone of the DNA sequences.

The covalent bond is herein formed through the catalytic activity of the enzyme T4 DNA ligase, and simultaneously split at the very same site by a restriction enzyme, which can recognize and cut DNA at specific positions. This newly-formed system is reversible and results directly in structural dynamics, which distinguishes it from previous artificially-generated dissipative structures.

The study, which took place with the aid of Walther's ERC Starting Grant “TimeProSAMat”, uses the dynamic synthesis of a polymer of DNA fragments, to show scientists how the lifetime, exchange frequency, or relative bond fraction of the DNA polymers can be controlled in dependence of the chemical fuel adenosine triphosphate and the enzyme concentrations.

The Freiburg researchers were able to sustain these dynamic steady states for several days. The chemical modifications of DNA to use it as a construction material are versatile and there are also many available restriction enzymes, explains Heinen, “So our concept enables wide-ranging access to innovative functional materials, which act outside thermodynamic equilibrium. And it does so with so far unique programming possibilities in its dynamic structural characteristics.”

Original publication:
Heinen, L., Walther, A. (2019): Programmable dynamic steady states in ATP-driven nonequilibrium DNA systems. In: Science Advances. Vol. 5, no. 7. DOI: 10.1126/sciadv.aaw0590

Contact:
Prof. Dr. Andreas Walther
Institute for Macromolecular Chemistry and FIT – Freiburg Center of Interactive Materials and Bioinspired Technologies
University of Freiburg
Tel.: 0761/203-96895
e-mail: andreas.walther@makro.uni-freiburg.de

https://www.pr.uni-freiburg.de/pm-en/press-releases-2019/living-components?set_l…

Media Contact

Nicolas Scherger idw - Informationsdienst Wissenschaft

All news from this category: Life Sciences

Articles and reports from the Life Sciences area deal with applied and basic research into modern biology, chemistry and human medicine.

Valuable information can be found on a range of life sciences fields including bacteriology, biochemistry, bionics, bioinformatics, biophysics, biotechnology, genetics, geobotany, human biology, marine biology, microbiology, molecular biology, cellular biology, zoology, bioinorganic chemistry, microchemistry and environmental chemistry.

Back to the Homepage

Comments (0)

Write comment

Latest posts

Seawater as an electrical cable !?

Wireless power transfers in the ocean For drones that can be stationed underwater for the adoption of ICT in mariculture. Associate professor Masaya Tamura, Kousuke Murai (who has completed the…

Rare quadruple-helix DNA found in living human cells with glowing probes

New probes allow scientists to see four-stranded DNA interacting with molecules inside living human cells, unravelling its role in cellular processes. DNA usually forms the classic double helix shape of…

A rift in the retina may help repair the optic nerve

In experiments in mouse tissues and human cells, Johns Hopkins Medicine researchers say they have found that removing a membrane that lines the back of the eye may improve the…

Partners & Sponsors

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close