Programmable structural dynamics successful for first time in self-organizing fiber structures
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."
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
Prof. Dr. Andreas Walther
Institute for Macromolecular Chemistry and FIT – Freiburg Center of Interactive Materials and Bioinspired Technologies
University of Freiburg
Nicolas Scherger | idw - Informationsdienst Wissenschaft
Biophysicists reveal how optogenetic tool works
29.05.2020 | Moscow Institute of Physics and Technology
Mapping immune cells in brain tumors
29.05.2020 | University of Zurich
In living cells, enzymes drive biochemical metabolic processes enabling reactions to take place efficiently. It is this very ability which allows them to be used as catalysts in biotechnology, for example to create chemical products such as pharmaceutics. Researchers now identified an enzyme that, when illuminated with blue light, becomes catalytically active and initiates a reaction that was previously unknown in enzymatics. The study was published in "Nature Communications".
Enzymes: they are the central drivers for biochemical metabolic processes in every living cell, enabling reactions to take place efficiently. It is this very...
Early detection of tumors is extremely important in treating cancer. A new technique developed by researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from normal tissue. The work is published May 25 in the journal Nature Nanotechnology.
researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from...
Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.
When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...
Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.
Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...
Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.
A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...
19.05.2020 | Event News
07.04.2020 | Event News
06.04.2020 | Event News
29.05.2020 | Materials Sciences
29.05.2020 | Materials Sciences
29.05.2020 | Power and Electrical Engineering