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 Measured for the first time: Direction of light waves changed by quantum effect
24.05.2017 | Vienna University of Technology

nachricht Physicists discover mechanism behind granular capillary effect
24.05.2017 | University of Cologne

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: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>