Nano-softball Made Of DNA
2008-04-09 0:00

From: sciencedaily.com

For quite some time, DNA, the stuff our genes are made of, has also been considered the building material of choice for nanoscale objects. A team led by Günter von Kiedrowski at the Ruhr University in Bochum has now made a dodecahedron (a geometric shape with twelve surfaces) from DNA building blocks. These objects are formed in a self-assembly process from 20 individual trisoligonucleotides, building blocks consisting of a “branching junction” and three short DNA strands.

A regular dodecahedron is a geometric shape made of 12 pentagons of equal size, three of which are connected at every vertex. This results in a structure with 30 edges and 20 vertices. In order to produce a hollow dodecahedral object from DNA, the researchers used 20 “three-legged” building blocks (three DNA strands connected together at one point). The centers of these building blocks represent the vertices of the dodecahedron. The three edges projecting from each vertex are formed when a single strand of DNA converts two neighboring bridging components into a double strand.

In order for this process to result in a dodecahedron and not some other random geometric object, all of the DNA strands must have a different sequence. Among these, there must, however, be pairs of complementary strands that can bind to each other.

By using a computer program, the researchers identified a set of 30 independent, 15-base-pair-long, double-stranded DNA sequences with similar physical properties. The double-stranded sequences were assigned to the individual edges of the dodecahedron and to specific vertices for termination. It was then determined which three single-stranded sequences needed to be attached to each three-legged junction for the predetermined structure to form.

The team synthesized the 20 computed trisoligonucleotides by means of a solid-phase synthesis. The three DNA strands were always attached by way of an aromatic six-membered carbon ring. When mixed in equal parts in a buffer solution, these building blocks do aggregate to form the expected product: regular dodecahedra. Atomic force microscopy images reveal them to be uniform particles with a diameter of about 20 nm. Under pressure, the dodecahedra are quite flexible, the can be deformed like “soft balls” without incurring any damage.

If the trisoligonucleotides are equipped with pendant “arms”, the dodecahedra can be outfitted with additional functional molecules. In this way, highly complex nanoconstructs, resembling little viruses in shape and size, should be accessible in the future. Potential applications range from medical diagnostics to nanoelectronics.

Journal reference: Self-Assembly of a DNA Dodecahedron from 20 Trisoligonucleotides with C3h Linkers, Angewandte Chemie International Edition, doi: 10.1002/anie.200702682. Nr. 14/2008

Adapted from materials provided by Wiley-Blackwell.

Article from: http://www.sciencedaily.com/releases/2008/04/080401110423.htm



Related Articles


Latest News from our Front Page

Confederate History - Dispelling the Myths
2015-07-03 3:28
History books, the media, the school systems, etc abound in falsehoods and inaccuracies of Confederate and Southern history. This fact sheet will help to clarify and dispell some of these rampant inaccuracies. MYTH - The War of 1861 - 1865 was fought over slavery. FACT - Terribly untrue. The North fought the war over money. Plain ...
Gays Rights May Open Door for Pedophile Rights
2015-07-03 3:31
Democrats have attempted to normalize pedophilia as a sexual orientation. A recent Supreme Court ruling on same-sex marriage may soon allow pedophiles to argue they are suffering discrimination. “Using the same tactics used by ‘gay’ rights activists, pedophiles have begun to seek similar status arguing their desire for children is a sexual orientation no different than heterosexual or homosexuals,” writes Jack Minor ...
Government Trolls Are Using ‘Psychology-Based Influence Techniques’ On YouTube, Facebook And Twitter
2015-07-03 3:56
Have you ever come across someone on the Internet that you suspected was a paid government troll? Well, there is a very good chance that you were not imagining things. Thanks to Edward Snowden, we now have solid proof that paid government trolls are using “psychology-based influence techniques” on social media websites such as YouTube, Facebook and Twitter. ...
Artificial Intelligence Takes the Battlefield: Who Is Really Running Jade Helm 15?
2015-07-03 2:31
Who is really going to be running Jade Helm 15? There is more to the story than just training for martial law in states designated as “hostile states” – already a chilling pretext with overtones of greater federal power that could spiral out of control. But it seems that it is actually A.I. – artificial intelligence – that is at the helm ...
Robot kills man at Volkswagen plant in Germany
2015-07-03 2:32
A 22-year-old worker was grabbed by the robot and crushed against a metal plate A robot has killed a man at a Volkswagen car factory in Germany. The 22-year-old worker died from injuries he sustained when he was trapped by a robotic arm and crushed against a metal plate. The man, who has not been named, was part of a team that ...
More News »