Self-assembly now easier to control

May 14, 2009

Nature has long perfected the construction of nanomachines, but David Gonzalez and his fellow researchers from Eindhoven University of Technology and Utrecht University under the leadership of Spinoza Award winner Bert Meijer, have brought the construction of artificial supramolecular structures a step closer by. The researchers managed to carefully control the self-assembly of guanosine, one of the building blocks of our DNA. Their research results were published by Nature Chemistry on April 19.

The natural world is a shining example when it comes to the self-assembly of molecules. However, it has not disclosed all of its secrets yet. Controlling the shape and structure of self-assembled systems continues to be a stumbling block for scientists. Yet such structures, in which the different molecules cooperate with each other, can have unrivalled characteristics. Self-assembly could provide the way forward for the future mass production of nanomaterials, nanodrugs and nanoelectronics.


A quadruplex of four DNA strands is an example of such a self-assembling structure. Guanosine molecules bind together to form such a G-quadruplex. The researchers managed to influence the formation of G-quadruplexes, using Coulombic interactions. They produced structures with 8, 12, 16, or even 24 guanosine molecules.

During the formation of G-quadruplexes, positively charged alkali metal ions are incorporated in the interior of the structure. Negatively charged anions, however, fall on the outside of the structure and are therefore exposed to the surrounding medium. Coulomb's law describes the forces that two electrical charges exert on each other. According to this law, that force depends on the distance between the negatively and positively charged ions and on the stabilising characteristics of the solution in which the self-assembly takes place. The negatively charged ions on the outside of the structure are of course exposed to this solution, as a result of which the solution determines the stability of the structure to a large extent.

By varying the two different factors, distance and solution, the researchers could regulate the formation of the G-quadruplexes. For example, they could build structures with different numbers of molecules. A structure with exactly 24 guanosine molecules had not previously been artificially constructed. This new perspective therefore provides opportunities for the regulation of self-assembling structures.
Nature publication

The authors of the article 'G-quadruplex self-assembly regulated by Coulombic interactions', published online in Nature Chemistry on 19 April 2009, are David González-Rodríguez, Joost van Dongen, Martin Lutz, Anthony Spek, Albert Schenning and Bert Meijer. The research was performed by the Institute for Complex Molecular Structures at Eindhoven University of Technology in cooperation with Utrecht University. Part of the research was financed by the NWO/Spinoza Award of Bert Meyer.

Netherlands Organization for Scientific Research

Related DNA Articles from Brightsurf:

A new twist on DNA origami
A team* of scientists from ASU and Shanghai Jiao Tong University (SJTU) led by Hao Yan, ASU's Milton Glick Professor in the School of Molecular Sciences, and director of the ASU Biodesign Institute's Center for Molecular Design and Biomimetics, has just announced the creation of a new type of meta-DNA structures that will open up the fields of optoelectronics (including information storage and encryption) as well as synthetic biology.

Solving a DNA mystery
''A watched pot never boils,'' as the saying goes, but that was not the case for UC Santa Barbara researchers watching a ''pot'' of liquids formed from DNA.

Junk DNA might be really, really useful for biocomputing
When you don't understand how things work, it's not unusual to think of them as just plain old junk.

Designing DNA from scratch: Engineering the functions of micrometer-sized DNA droplets
Scientists at Tokyo Institute of Technology (Tokyo Tech) have constructed ''DNA droplets'' comprising designed DNA nanostructures.

Does DNA in the water tell us how many fish are there?
Researchers have developed a new non-invasive method to count individual fish by measuring the concentration of environmental DNA in the water, which could be applied for quantitative monitoring of aquatic ecosystems.

Zigzag DNA
How the cell organizes DNA into tightly packed chromosomes. Nature publication by Delft University of Technology and EMBL Heidelberg.

Scientists now know what DNA's chaperone looks like
Researchers have discovered the structure of the FACT protein -- a mysterious protein central to the functioning of DNA.

DNA is like everything else: it's not what you have, but how you use it
A new paradigm for reading out genetic information in DNA is described by Dr.

A new spin on DNA
For decades, researchers have chased ways to study biological machines.

From face to DNA: New method aims to improve match between DNA sample and face database
Predicting what someone's face looks like based on a DNA sample remains a hard nut to crack for science.

Read More: DNA News and DNA Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to