DNA directly photographed for the first time
2012 12 03

By Eli MacKinnon | NBCNews



Fifty-nine years after James Watson and Francis Crick deduced the double-helix structure of DNA, a scientist has captured the first direct photograph of the twisted ladder that props up life.

Enzo Di Fabrizio, a physics professor at Magna Graecia University in Catanzaro, Italy, snapped the picture using an electron microscope.

Previously, scientists had only seen DNA’s structure indirectly. The double-corkscrew form was first discovered using a technique called X-ray crystallography, in which a material’s shape is reconstructed based on how X-rays bounce after they collide with it.


A bundle of DNA is supported by two silicon pillars.



DNA’s double-helix structure is on display for the first time in this electron microscope photograph of a small bundle of DNA strands.


But Di Fabrizio and his colleagues developed a plan to bring DNA out of hiding. They built a nanoscopic landscape of extremely water-repellant silicon pillars. When they added a solution that contained strands of DNA into this scene, the water quickly evaporated and left behind cords of bare DNA that stretched like tightropes between the tiny mesas.

They then shone beams of electrons through holes in the silicon bed, and captured high-resolution images of the illuminated molecules.

Di Fabrizio’s images actually show a thread of several interwoven DNA molecules, as opposed to just two coupled strands. This is because the energy of the electrons used would be enough to destroy an isolated double helix, or a single strand from a double helix.

But with the use of more sensitive equipment and lower energy electrons, Di Fabrizio thinks that snapshots of individual double helices will soon be possible, New Scientist reports.

Molecules of DNA, or deoxyribonucleic acid, store the genetic instructions that govern all living organisms’ growth and function.

Di Fabrizio’s innovation will allow scientists to vividly observe interactions between DNA and some of life’s other essential ingredients, such as RNA (r ibonucleic acid ). The results of Di Fabrizio’s work were published in the journal NanoLetters.


Article from: msnbc.msn.com







Related Articles
’Odd Little Creature’ Skips Sex and Eats DNA
The US Is Collecting the DNA of World Leaders
Bigfoot DNA: The Proof is Out There?
Asexual, All-Female Animal’s Survival Trick: DNA Hijacking
DNA of Hungarian mummies may help combat tuberculosis
Life on Mars? Scientists hope to find it by decoding Martian DNA - ’We Can Rebuild Them’
“We could put the whole world’s knowledge in 4 grams of DNA”


Latest News from our Front Page

Extremists to have Facebook and Twitter vetted by anti-terror police
2014 09 30
Theresa May to announce new Extremist Disruption Orders to strengthen counter-terrorism if the Tories win the next general election Extremists will have to get posts on Facebook and Twitter approved in advance by the police under sweeping rules planned by the Conservatives. They will also be barred from speaking at public events if they represent a threat to “the functioning of democracy”, ...
Water rationing hits California: limit of 50 gallons per person per day or face fines of $500
2014 09 29
Millions of Californians are about to be hit with strict water rationing -- daily "allocation" numbers that represent the maximum amount of water you’re allowed to use for any purpose. Households that exceed the allocation limit will face stiff fines of hundreds of dollars per violation. "In July, the State Water Resources Control Board passed stage one emergency regulations, giving powers ...
Much of Earth’s Water is Older than the Sun
2014 09 29
Much of the water on Earth and elsewhere in the solar system likely predates the birth of the sun, a new study reports. The finding suggests that water is commonly incorporated into newly forming planets throughout the Milky Way galaxy and beyond, researchers said — good news for anyone hoping that Earth isn’t the only world to host life. “The implications of ...
Did the Vikings Get a Bum Rap?
2014 09 29
A Yale historian wants us to rethink the terrible tales about the Norse. This illustration shows the stereotype of Viking marauders wreaking mayhem, even on clergy. The scene depicts the monastery at Clonmacnoise, Ireland. The Vikings gave no quarter when they stormed the city of Nantes, in what is now western France, in June 843—not even to the monks barricaded in the ...
David Cameron Says Non-Violent Conspiracy Theorists Are Just As Dangerous As ISIS
2014 09 29
David Cameron told the U.N. that "non-violent extremism" is just as dangerous as terrorism and must be eradicated using all means at the government’s disposal. He references 9/11 and 7/7 Truthers as examples of the type of extremism that must be dealt in a similar fashion to ISIS. If you thought Obama’s War is Peace speech to the U.N. was creepy, ...
More News »