DNA was first isolated in the mid 1800s, but its true significance was not discovered until much later. As the field of molecular biology developed, science slowly discovered the incredible importance of DNA DNA carries all our genetic information across the generations. It took decades to figure out what DNA looks like, but when even when Watson, Crick, and Franklin posited the double-helix, it was an indirect observation. We have never been able to actually see DNA until now.
The 1953 breakthrough describing the double-helix was confirmed using x-ray crystallography. This is a process in which a molecule is bombarded with x-rays which bounce off the atoms. By observing the patterns of the reflected x-rays, scientists can calculate the location of atoms in the molecule. The new research from Enzo di Fabrizio at the University of Genoa is different because to visualizes DNA directly with an electron microscope.
The team created a water repellent surface that caused liquid in samples to dry out very quickly and deposit suspended strands of DNA. The surface is made up of tiny micro pillars that catch the DNA, holding it up where images can be taken. The results are pretty amazing you can actually see the repeating spiral pattern of DNA.
This first round of images cannot capture individual double-helices. The electron microscope needs to output so much energy to take the pictures, that it blows single strands apart. What youre seeing here are so-called DNA cords, bundles of six single strands wrapped around a central one.
The hope is that a more sensitive detector capable of capturing images at lower electron energies will allow the researchers to see single strands of DNA. The work could eventually allow scientists to closely study the way proteins and chemical agents interact with your DNA.
via New Scientist
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Electron microscope reveals what DNA really looks like