Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Giant Virus Revealed in 3-D Using X-ray Laser

04.03.2015

Experiment Compiles Hundreds of Images, Reveals Inner Details of Intact ‘Mimivirus’

For the first time, researchers have produced a 3-D image revealing part of the inner structure of an intact, infectious virus, using a unique X-ray laser at the Department of Energy’s SLAC National Accelerator Laboratory. The virus, called Mimivirus, is in a curious class of “giant viruses” discovered just over a decade ago.


Uppsala University

This computerized rendering shows a cutaway view of a collection of about 200 X-ray patterns, produced in an experiment at SLAC’s Linac Coherent Light Source X-ray laser. The images were combined to produce a 3-D rendering of an intact Mimivirus, a giant virus that was at first mislabeled as a bacterium because of its size.


Uppsala University

This rendering shows a 3-D reconstruction of a Mimivirus, based on an analysis of data obtained in an experiment at SLAC's Linac Coherent Light Source X-ray laser that show the electron density of an intact Mimivirus, a type of giant virus. The blue regions represent the areas of highest density.

The experiment at SLAC’s Linac Coherent Light Source (LCLS), a DOE Office of Science User Facility, establishes a new technique for reconstructing the 3-D structure of many types of biological samples from a series of X-ray laser snapshots.

“Ever since I started in this field of X-ray laser research, this has always been the dream – to acquire 3-D images of real biological samples,” said Tomas Ekeberg, a biophysicist at Uppsala University in Sweden and lead author of the study, published March 2 in Physical Review Letters. “This is fantastic – it’s a breakthrough in our research.”

Mysterious World of Giant Viruses

Mimivirus is so big – its volume is thousands of times larger than the smallest viruses and even larger than some bacteria – that it was misclassified as a bacterium until 2003. Subsequent discoveries have found other giant viruses, some of which are even larger.

Mimivirus is also genetically complex, with nearly 1,000 major genes compared to only a handful in the HIV virus.

Scientists have been trying to determine the inner structure of these giant viruses to learn more about their origins: For example, did they borrow genes over time from the host organisms they infect, like amoebas? Did they precede cell-based life or devolve from cell-based organisms?

Light Pattern Portrait

In the LCLS experiment, researchers sprayed a gas-propelled aerosol containing active Mimivirus samples in a thin stream into the X-ray laser beam, which scattered off the viruses and produced light patterns on a detector that were recorded as diffraction images.

Researchers customized sophisticated analysis software developed at Cornell University to compile hundreds of individual images from separate virus particles into a single 3-D portrait showing the general shape and inner features of Mimivirus. Each image captured a projection of a separate virus particle at a random orientation, so the collection of images of viruses in different orientations provided a more complete, 3-D view.

While the technique used at LCLS did not provide high-resolution details of the internal virus structure, it did confirm that its contents are lopsided, with an area that appears more densely concentrated.

“We can see quite clearly that the inside of these viruses is not uniform,” Ekeberg said.

This same general feature had also been seen before using an electron-based imaging technique with frozen samples, and LCLS allows studies of viruses and other biological samples in a more natural, intact state. Researchers said that LCLS shows promise for achieving sharper images that reveal more inner details in the future because of the uniquely intense, penetrating power of its X-rays.

3-D Vision for X-ray Laser Studies

The same technique was recently used to study bacterial cell structures. LCLS managers have launched an initiative with the scientific community to improve techniques for imaging intact, biological particles that are difficult to study.

Janos Hajdu, a professor of biophysics at Uppsala and a pioneer in biological particle imaging with X-ray lasers, said the research team plans to apply the 3-D imaging technique to other types of samples and to improve the image quality. He said, “The next Holy Grail is to study large, single proteins at LCLS.”

Participants in the research included scientists from SLAC’s LCLS, Lawrence Berkeley National Laboratory and Kansas State University; Uppsala University in Sweden; Aix Marseille University and CEA-Saclay in France; the Center for Free-Electron Laser Science at DESY, University of Hamburg in Germany, PNSensor GmbH, Max Planck Institute’s Semiconductor Laboratory, Max Planck Institute for Extraterrestrial Physics in Germany, and the European XFEL in Germany; National University of Singapore; and The University of Melbourne in Australia. The work was supported by the Swedish Research Council, the Knut and Alice Wallenberg Foundation, the European Research Council, the Röntgen-Ångström Cluster, and Stiftelsen Olle Engkvist Byggmästare.

SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, Calif., SLAC is operated by Stanford University for the U.S. Department of Energy’s Office of Science. For more information, please visit slac.stanford.edu.

SLAC National Accelerator Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

Andrew Gordon | newswise

Further reports about: 3-D Accelerator Germany Giant LCLS Laser SLAC Virus X-ray biological samples technique viruses

More articles from Physics and Astronomy:

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

nachricht NASA's fermi finds possible dark matter ties in andromeda galaxy
22.02.2017 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>