SSRL Science Highlights Archive

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. Contact us to add your most recent publications to this collection.

September 2017
David Barondeau, Texas A&M University

Iron-sulfur (Fe-S) clusters are cofactors that are required for the function of proteins in many critical cellular processes.  All living organisms synthesize and distribute Fe-S clusters using complex biosynthetic pathways. In humans, the mitochondrial cysteine desulfurase, NFS1, is responsible for the conversion of the sulfur-containing amino acid, cysteine, to alanine and persulfide sulfur, an intermediate in Fe-S cluster synthesis. In contrast to the analogous cysteine desulfurase in prokaryotes, the eukaryotic NFS1 enzyme requires accessory proteins, ISD11 and ACP, for its function. A team of scientists investigated the structure of the NFS1-ISD11-ACP complex in order to unravel NFS1’s requirement of ISD11 and ACP for function.

Macromolecular Crystallography
BL7-1
September 2017
Johanna Nelson Weker, SSRL
Figure 1

Given our increasing dependence of rechargeable battery containing electronic devices, including electric cars, it is important to engineer these systems to mitigate potential for catastrophic battery failure. One possible source of lithium ion battery failure is over-discharge (over-lithiation) of the cathode, which can permanently damage the battery. Electronic battery management systems are programmed to prevent and identify such failures, but sometimes do not catch problems of over-lithiation when they occur. To better understand the characteristics of battery failure from over-discharging, a team of scientists studied the chemical and morphological changes that occur from over-lithiation of a lithium battery cathode.

X-ray Absorption Spectroscopy
BL4-1
August 2017
Cheryl Kerfeld, Lawrence Berkeley National Laboratory
Figure 1 BMC Shell

Bacterial cells have subcellular features that function as organelles called microcompartments. Bacterial microcompartments organize cellular metabolism. These compartments help increase reaction rates by colocalizing reaction components. They can also sequester sensitive or damaging reactants or products from the rest of the cell. Part of bacterial microcompartment function is to allow only some molecules to cross into the compartment while keeping out others. How this selectivity is possible is not well understood.

Macromolecular Crystallography
BL12-2
August 2017
Addison V. Wright, University of California, Berkeley, Jennifer A. Doudna, University of California, Berkeley
image

CRISPR, a powerful new tool that can target and change specific sequences of DNA, is based on a prokaryotic immune system response. The first step of bacterial immunity via CRISPR is placing sequences of foreign (viral) DNA between specific palindromic DNA repeats in the bacterial genome. The enzyme complex Cas1-Cas2 must target the correct DNA locus for integration, since insertion of the viral DNA into other areas of the genome may cause damage to the bacteria.

Macromolecular Crystallography
BL9-2
July 2017
Elizabeth Shoenfelt, Columbia University, Benjamin Bostick, Columbia University
image

Diatoms, single-celled marine algae that create beautiful, symmetric cell walls composed of silica, are critical to ocean ecosystems. Responsible for up to 20% of photosynthesis in oceans, these phytoplankton are also an important part of Earth’s carbon cycles. The potential of diatoms and other phytoplankton to sequester atmospheric CO2 has led to geoengineering ideas like “iron fertilization” of oceans.

X-ray Absorption Spectroscopy
BL4-1, BL4-3
July 2017
Dimosthenis Sokaras, Stanford Synchrotron Radiation Lightsource, Angel Garcia-Esparza, KAUST, Kazuhiro Takanabe, KAUST

Molecular hydrogen (H2) is a promising carrier of energy for a future that uses more sustainable sources of fuel. H2 created from splitting H2O using renewable energy methods could result in no carbon footprint energy use. While methods of water splitting are being developed, reverse reactions are a problem.

X-ray Absorption Spectroscopy
BL4-1, BL6-2b
June 2017
Amrita Bhattacharyya, Colorado State University, Thomas Borch, Colorado State University

The radioactive element uranium is well-known for its role in nuclear energy. People mine naturally occurring uranium from deep sandstone deposits called roll fronts. Scientists have long thought that abiotic chemical reactions that occur over millions of years resulted in formation of crystalline uranium. An international team of scientists has challenged this basic theory, finding evidence for a different genesis for uranium in roll front deposits. 

X-ray Absorption Spectroscopy
BL4-1, BL11-2
June 2017
Davide Robbiani, The Rockefeller University, Margaret MacDonald, The Rockefeller University, Michel Nussenzweig, The Rockefeller University, Pamela Bjorkman, California Institute of Technology
Santa Maria

Using data collected at SSRL Beam Line 12-2, a team of scientists have determined the molecular structure formed between the Zika envelope protein and neutralizing human antibodies. 

Macromolecular Crystallography
BL12-2
May 2017
Kristin Boye, Stanford Synchrotron Radiation Lightsource, John Bargar, Stanford Synchrotron Radiation Lightsource
Floodplains Image

While scientists recognize that oxygen-free soil stores large amounts of carbon, knowledge about the processes that protect and preserve carbon-rich molecules in these environments is lacking. In oxygen-rich soil, microbes break down organic molecules through aerobic respiration, allowing carbon to escape the ground as carbon dioxide gas.

X-ray Absorption Spectroscopy
BL11-2
April 2017
Emmanuel Skordalakes, The Wistar Institute, University of Pennsylvania
Figure 1

Famous for their role in the process of aging, telomeres are the regions of repetitive DNA sequences at the ends of our chromosomes. These repeats are critical for preserving the structure and function of our DNA in concert with numerous cellular factors. One factor responsible for the regulation and maintenance of telomere length is the shelterin complex, composed of six proteins including one called POT1.

Macromolecular Crystallography
BL12-2

Pages

Subscribe to SSRL Science Highlights
Find Stanford Synchrotron Radiation Lightsource on FlickrFind Stanford Synchrotron Radiation Lightsource on YouTubeFind Stanford Synchrotron Radiation Lightsource on Twitter