X-rays intended to elucidate the structure of biomolecules may actually damage and alter key parts of the molecules. A research team led by a group from Lawrence Berkeley National Laboratory (in collaboration with researchers from Max-Planck-Institut Mülheim, ESRF, SSRL, and TU Berlin and Freie Universität, Berlin) discovered this while investigating the Mn4Ca complex, a site crucial for splitting water into oxygen during photosynthesis.
Approximately 1,600 scientists visit SSRL annually to conduct experiments in broad disciplines including life sciences, materials, environmental science, and accelerator physics. Science highlights featured here and in our monthly newsletter, Headlines, increase the visibility of user science as well as the important contribution of SSRL in facilitating basic and applied scientific research. Many of these scientific highlights have been included in reports to funding agencies and have been picked up by other media. Users are strongly encouraged to contact us when exciting results are about to be published. We can work with users and the SLAC Office of Communication to develop the story and to communicate user research findings to a much broader audience. Visit SSRL Publications for a list of the hundreds of SSRL-related scientific papers published annually and to add your most recent publications to this collection.
While we continue to refine our science highlights content you may access older science summaries that date between 04/2001 to 06/2010 by visiting http://www-ssrl.slac.stanford.edu/science/sciencehighlights.html. We will be offering science summaries that date from 06/2012 to the present soon.
September 2005
X-ray Absorption Spectroscopy
September 2005
We have to defend ourselves from the challenge of microbial pathogens every day. Innate immune system represents the first line of defense against microorganisms by selectively detecting foreign molecules. The Toll-like receptors (TLRs) are one of the most important sensors of the innate immune system and recognize conserved molecules from various pathogens including viruses, bacteria, fungi and parasites.
BL11-1
August 2005
Manganese oxides form in the oceanic water column as a result of the bacterially catalyzed oxidation of a relatively abundant form of dissolved manganese. As they settle through the water column, manganese oxides participate in myriad chemical reactions important to sea life and to maintaining the trace-metal composition of sea water. These reactions profoundly impact the geochemical cycling of carbon, nitrogen, sulfur, nutrients and containments.
July 2005
Ion channels in our cells generate the nerve impulses that enable the heart to beat, the body to move, and sensation and thought to occur. Scientists from the Salk Institute for Biological Studies have identified a tiny flexible gateway that controls the rapid-fire opening and closing of a family of ion channels through which nerve-triggering potassium ions flow in and out of cells of the body. Malfunctions in the channels leads to several human diseases, including epilepsy, cardiac arrhythmias and muscle disorders.
Macromolecular Crystallography
July 2005
Using x-ray diffraction data collected on Beam Line 9-2 at SSRL, and other beam lines at the ESRF and BNL, scientists at The Salk Institute for Biological Studies discovered the three-dimensional structure of a protein that bacteria use to make biologically active compounds. By effectively engineering this protein, scientists may be able to create new drugs with therapeutic properties.
X-ray diffraction
BL9-2
June 2005
Mercury (Hg) is a naturally occurring element that poses considerable health risks to humans, with high exposure levels resulting in damage to the brain, heart, kidneys, lungs, and immune system. Young children and unborn babies are particularly vulnerable to mercury, which can affect their nervous systems and impair their neurological development. As a result, mercury is one of the most strictly regulated pollutants by the Environmental Protection Agency (EPA), which controls mercury emissions from coal-fired power plants and issues consumption advisory warnings for various types of fish, the primary route of mercury exposure to humans
BL4-3, BL11-2
June 2005
Iron metals oxidize to rust, losing electrons and gaining positive charge. Iron metals typically exist in an oxidation state of +2 or +3 (2 or 3 electrons less than a neutral iron atom). However, chemists have long thought that iron compounds with even higher oxidation states play important roles in enabling chemical reactions in metal-containing proteins.
X-ray Absorption Spectroscopy
May 2005
An early transcription of Archimedes' mathematical theories has been brought to light through the probing of high-intensity x-rays at SSRL's BL6-2. The text contains part of the Method of Mechanical Theorems, one of Archimedes' most important works, which was probably copied out by a scribe in the tenth century. The parchment on which it was written was later scraped down and reused as pages in a twelfth century prayer book, producing a document known as a palimpsest (which comes from the Greek, meaning 'rubbed smooth again').
May 2005
Cadmium is known to be extremely toxic to mammals, and is generally viewed alongside mercury as an environmental problem and toxic element that is not used by nature in any way. A Brief Communication in the May 5 issue of the journal Nature shows that we need to revise our opinion of cadmium. The paper reports the purification and characterization of a previously unknown metalloenzyme from the marine diatom Thalassiosira weissflogii that specifically uses cadmium to achieve its biological function. This is the first cadmium enzyme that has been discovered.
X-ray Absorption Spectroscopy
BL7-3
April 2005
The chemically treated wood used for playgrounds, fences and decks appears to be less toxic than feared. The chromated copper arsenate (CCA) mix protects commercial outdoor grade lumber from weathering, but in recent years the public and the government realized the chemicals could be potentially risky to the many people exposed to the ubiquitous wood.
X-ray absorption spectroscopy imaging
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