For the first time ever, researchers have produced a XNUMXD image showing the internal structure of an infectious virus using an X-ray laser. The virus, named Mimivirus, is part of an intriguing family of 'giant viruses' that were only discovered about a decade ago
![This computer simulation shows a cross-section from a collection of about 200 x-ray patterns. The images were merged into a combined XNUMXD image of a giant virus (Mimivirus) which until today was mistakenly classified as a bacterium due to its size. [Courtesy of Uppsala University]](https://www.hayadan.org.il/images/content3/2015/03/mimi1-500x500.jpg)
For the first time ever, researchers have produced a XNUMXD image showing the internal structure of an infectious virus using an X-ray laser. The virus, named Mimivirus, is part of an intriguing family of 'giant viruses' that were only discovered about a decade ago.
The experiment, conducted within the framework of the US Department of Energy, reveals a new method for producing a XNUMXD structure of many types of biological compounds with the help of a series of many laser photographs in the X-ray field. "Since I started working in this area of X-ray laser research, it has always been my dream - to get XNUMXD images of real biological compounds," said Tomas Ekeberg, a biophysicist at Uppsala University in Sweden and lead author of the paper published in the scientific journal Physical Review. Letters.
The Mimivirus (Wikipedia) is so large - its volume is thousands of times larger than the smallest viruses and even larger than some bacteria - that it was mistakenly classified as a bacterium until 2003. Studies conducted after its discovery revealed other giant viruses, some even larger than it. In addition, this virus has great genetic complexity, and contains almost 1000 main genes, compared to only a few genes in the virus that causes AIDS (HIV).
Scientists have tried to determine the internal structure of these giant viruses in order to learn about their origin: for example, did they borrow genes over time from host organisms they were infected with, such as amoebae? Do they have an independent life cycle or are they dependent on their host?
During the experiment, the researchers spray a gaseous aerosol containing the active viruses in the form of a thin stream into a laser beam of X-rays, which decompose from the viruses and create light patterns that are absorbed by special detectors that record the diffraction images. The researchers used sophisticated analysis software developed at Cornell University to merge hundreds of individual images from separate virus particles to obtain a joint XNUMXD portrait showing the overall shape and internal characteristics of the Mimivirus. Each image captured a different projection of a separate virus in a random direction, so the collection of images of the virus in the different directions provides the more complete XNUMXD image of the entire virus.
Although the discussed method does not provide high resolution details about the internal structure of the virus, it did verify the distribution of the material in the general structure. "We were able to clearly see that the content inside these viruses is not uniform in terms of its location," said the lead researcher. The researchers hope that in the future the method will be able to provide more precise details regarding the internal structure of these viruses, and has even been used to study the structures of bacterial cells.
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Dr. Dror Bar-Nir
I realised. Thank you.
Miracles, the virus can be observed under a light microscope, but not in the details of its structure, as is not possible with most bacteria.
Amazing discovery! Over the years I have become similar to a virus living in my body. I became so ugly that I had to undergo renovations both in Photoshop and at the only therapist in the Middle East who agreed to touch me.
If the virus is bigger than a bacterium, why can't it be viewed under a microscope in a normal way?