First high-speed hard X-ray microscopic movies at a free-electron laser

New technique enables investigation of industrially relevant materials and processes in motion.

A group of researchers has for the first time performed high-speed microscopy using an X-ray laser at the European XFEL in Schenefeld near Hamburg, Germany. The method allows for observations of processes that take place at speeds up to a few kilometres per second, paving the way for 3D microscopic movies of fast phenomena, with important potential industrial applications. Such movies could show what happens during complex processes with a resolution at the sub-micrometre level, which is less than the diameter of a human hair, while also teasing out hidden internal details. While most other applications of X-ray lasers are based on the short wavelength of their X-ray flashes, making images that reach atomic resolution possible, this use takes advantage of the penetrating properties of X-rays. The resulting images, which are on the microscopic rather than atomic scale, reveal the internal structures of complex processes such as fluid cavitation at high speed. The research, which has been published in the journal Optica, was led by scientists from the Center for Free-Electron Laser Science (CFEL) in Hamburg (a collaboration between DESY, Universität Hamburg, and the Max Planck Society) and the European XFEL and involves scientists from P.J. Šafárik University in Slovakia, Lund University in Sweden, Diamond Light Source and University College London in the UK, the Karlsruhe Institute of Technology in Germany, and the European Synchrotron Radiation Facility (ESRF) in France.

>Read more on the European XFEL website

Illustration: X-ray microscopic image of a bursting glass capillary, taken at the SPB/SFX instrument at the European XFEL. The image on the left shows the image produced from the experiment. The middle version shows the direction of the motion of debris, showing the spinning glass fragments and details of turbulence in the water. The right version shows the velocity of the debris in metres per second. Download to view video here.
Credit: European XFEL

Researchers create most complete high-res atomic movie of photosynthesis to date

In a major step forward, SLAC’s X-ray laser captures all four stable states of the process that produces the oxygen we breathe, as well as fleeting steps in between. The work opens doors to understanding the past and creating a greener future.

Despite its role in shaping life as we know it, many aspects of photosynthesis remain a mystery. An international collaboration between scientists at SLAC National Accelerator Laboratory, Lawrence Berkeley National Laboratory and several other institutions is working to change that. The researchers used SLAC’s Linac Coherent Light Source (LCLS) X-ray laser to capture the most complete and highest-resolution picture to date of Photosystem II, a key protein complex in plants, algae and cyanobacteria responsible for splitting water and producing the oxygen we breathe. The results were published in Nature today.

Explosion of life

When Earth formed about 4.5 billion years ago, the planet’s landscape was almost nothing like what it is today. Junko Yano, one of the authors of the study and a senior scientist at Berkeley Lab, describes it as “hellish.” Meteors sizzled through a carbon dioxide-rich atmosphere and volcanoes flooded the surface with magmatic seas.
Over the next 2.5 billion years, water vapor accumulating in the air started to rain down and form oceans where the very first life appeared in the form of single-celled organisms. But it wasn’t until one of those specks of life mutated and developed the ability to harness light from the sun and turn it into energy, releasing oxygen molecules from water in the process, that Earth started to evolve into the planet it is today. This process, oxygenic photosynthesis, is considered one of nature’s crown jewels and has remained relatively unchanged in the more than 2 billion years since it emerged.

>Read more on the SLAC website (for LCLS)
>Read also the article on the Berkeley website (for ALS)

Image: Using SLAC’s X-ray laser, researchers have captured the most complete high-res atomic movie to date of Photosystem II, a key protein complex in plants, algae and cyanobacteria responsible for splitting water and producing the oxygen we breathe.
Credit: Gregory Stewart, SLAC National Accelerator Laboratory)

High-Speed Movie Aids Scientists Who Design Glowing Molecules

A research team captured ultrafast changes in fluorescent proteins between “dark” and “light” states.

The crystal jellyfish swims off the coast of the Pacific Northwest and can illuminate the waters when disturbed. That glow comes from proteins that absorb energy and then release it as bright flashes.

To track many of life’s activities, biologists took a cue from this same jellyfish.

Scientists collected one of the proteins found in the sea creatures, green fluorescent protein (GFP), and engineered a molecular light switch that would glow or remain dark depending on specific experimental conditions. The glowing labels are attached to molecules in living cells so researchers can highlight them during imaging experiments. They use these fluorescent markers to understand how a cell responds to changes in its environment, identify which molecules interact within a cell and track the effects of genetic mutations.

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Picture: Aequorea victoria, also called the crystal jelly, is a bioluminescent jellyfish that lives near the Pacific coast of North America. (Gary Kavanagh/iStockphoto.com)

 

Molecular Movie

Researchers Create Molecular Movie of Virus Preparing to Infect Healthy Cells

With SLAC’s X-ray laser, scientists captured a virus changing shape and rearranging its genome to invade a cell.

A research team has created for the first time a movie with nanoscale resolution of the three-dimensional changes a virus undergoes as it prepares to infect a healthy cell. The scientists analyzed thousands of individual snapshots from intense X-ray flashes, capturing the process in an experiment at the Department of Energy’s SLAC National Accelerator Laboratory.

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