Jul. 07, 2014
Macromolecular complexes composed of self-assembling proteins and nucleic acids hold promise for a wide range of applications, including drug delivery, sensing and molecular electronics. Scientists have developed a broad array of x-ray scattering techniques for characterizing the shape and surface morphology of these complexes, but probing their internal structure remains a challenge. Changyong Song and colleagues from the RIKEN SPring-8 Center and RIKEN Advanced Institute for Computational Science have now devised a structural analysis scheme based on complementary advanced x-ray techniques that has allowed them to peer inside an RNA macromolecular complex for the first time. Results were published in Nature Communications.
moreJun. 23, 2014
Physicists at HZB have developed a process to generate improved lenses for X-ray microscopy that provide both better resolution and higher throughput. To accomplish this, they fabricate three-dimensional X-ray optics for volume diffraction that consist of on-chip stacked Fresnel zone plates. These three-dimensional nanostructures focus the incident X-rays much more efficiently and enable improved spatial resolution below ten nanometres. Results have been published in the journal Nano Research.
moreJun. 18, 2014
Progress in the field of nanotechnology can only be achieved, if analytical methods for the characterization of nanostructures continuously improve. Due to the structure's small size visible light cannot be utilized for nanoanalytical techniques. In point of fact, microscopic methods with electron waves or X-rays must be applied here, as the wavelengths, they work with, are small enough. Multilayer Laue lenses (MLL) offer a most promising approach to developing highest resolution X-ray optics.
moreApr. 22, 2014
The tropical disease malaria is caused by the Plasmodium parasite. For its survival and propagation, Plasmodium requires a protein called actin. Scientists of the Helmholtz Centre for Infection Research (HZI) in Germany used high-resolution structural biology methods to investigate the different versions of this protein in the parasite in high detail. Their results, published in the scientific journal PLOS Pathogens, may in the future contribute to the development of tailor-made drugs against malaria-a disease that causes more than half a million deaths per year.
moreApr. 04, 2014
In biology, a protein's shape is key to understanding how it causes disease or toxicity. Researchers who use X-rays to take snapshots of proteins need a billion copies of the same protein stacked and packed into a neat crystal. Now, scientists using exceptionally bright and fast X-rays can take a picture that rivals conventional methods with a sheet of proteins just one protein molecule thick.
moreMar. 27, 2014
Scientists have used a particle accelerator to obtain high-speed 3D X-ray visualizations of the flight muscles of flies. The team from Oxford University, Imperial College, and the Paul Scherrer Institute (PSI) developed a groundbreaking new CT scanning technique at the PSI's Swiss Light Source to allow them to film inside live flying insects. Their article, including 3D movies of the blowfly flight motor, is published in the open access journal PLOS Biology. The movies offer a glimpse into the inner workings of one of nature's most complex mechanisms, showing that structural deformations are the key to understanding how a fly controls its wingbeat (see videos).
moreMar. 22, 2014
How does the hip joint of a crawling weevil move? A technique to record 3D X-ray films showing the internal movement dynamics in a spatially precise manner and, at the same time, in the temporal dimension has now been developed by researchers at ANKA, KIT's Synchrotron Radiation Source. The scientists applied this technique to a living weevil. From up to 100,000 two-dimensional radiographs per second, they generated complete 3D film sequences in real time or slow motion. The results are now published in the Proceedings of the National Academy of Sciences (PNAS).
moreMar. 05, 2014
It's an odd twist. For scientists to determine if a cell is functioning properly, they must destroy it. This is what happens in X-ray fluorescence microscopy when biological specimens are exposed to ionizing radiation, which provides images with a level of detail that conventional microscopes just can't match. This exposure can change what is being imaged in profound ways, possibly giving false accounts of how the cell actually works. To address this issue, researchers at the U.S. Department of Energy's (DOE) Argonne National Laboratory created a new probe that freezes cells to "see" at greater detail without damaging the sample.
moreMar. 04, 2014
Göttingen-based scientists working at DESY's PETRA III research light source have carried out the first studies of living biological cells using high-energy X-rays. The new method shows clear differences in the internal cellular structure between living and dead, chemically fixed cells that are often analysed. "The new method for the first time enables us to investigate the internal structures of living cells in their natural environment using hard X-rays," emphasises the leader of the working group, Prof. Sarah Köster from the Institute for X-Ray Physics of the University of Göttingen. The researchers present their work in the journal Physical Review Letters.
moreFeb. 09, 2014
By using a novel X-ray technique, researchers have observed a catalyst surface at work in real time and were able to resolve its atomic structure in detail. The new technique, pioneered at DESY's X-ray light source PETRA III, may pave the way for the design of better catalysts and other materials on the atomic level. It greatly speeds up the determination of atomic surface structures and enables live recordings of surface reactions like catalysis, corrosion and growth processes with a time resolution of less than a second.