Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING LLC
GLOBETECH PUBLISHING LLC
GLOBETECH MEDIA

Molecular X-Ray Camera Probes Biomolecules to Individual Atoms

By BiotechDaily International staff writers
Posted on 11 Jun 2012
Image: This rendering shows a lysozyme structural model against its X-ray diffraction pattern from SLAC’s Linac Coherent Light Source (LCLS), a powerful X-ray laser facility (Photo courtesy of Anton Barty/DESY).
Image: This rendering shows a lysozyme structural model against its X-ray diffraction pattern from SLAC’s Linac Coherent Light Source (LCLS), a powerful X-ray laser facility (Photo courtesy of Anton Barty/DESY).
Researchers have captured high-resolution images of simple lysozyme biomolecules using sophisticated X-ray crystallography technology.

An international team led by the US Department of Energy’s (DOE) SLAC National Accelerator Laboratory (Menlo Park, CA, USA) has proved how the world’s most powerful X-ray laser can assist in decoding the structures of biomolecules, and in the processes helped to forge vital new research paths in biology.

The researcher’s experiments, reported online May 31, 2012, in Science, used SLAC’s linac coherent light source (LCLS) to capture ultra-high-resolution views of crystallized biomolecules, including a small protein found in egg whites called lysozyme. For many years, scientists have reconstructed the shape of biologic molecules and proteins by illuminating crystallized samples with X-rays to study how they scatter the light. The scientists’ work with lysozyme represents the first-ever high-resolution experiments employing serial femtosecond crystallography--the split-second imaging of tiny crystals using ultrashort, ultrabright X-ray laser pulses.

The technique utilized a higher resolution than earlier achieved using X-ray lasers, allowing scientists to use smaller crystals than typical with other methods, and could also enable researchers to view molecular dynamics in a way never before possible. “We were able to actually visualize the structure of the molecule at a resolution so high we start to infer the position of individual atoms,” said Dr. Sébastien Boutet, a staff scientist at LCLS who led the research. “Not only that, but the structure we observed matches the known structure of lysozyme and shows no significant sign of radiation damage, despite the fact that the pulses completely destroy the sample. This is the first high-resolution demonstration of the ‘diffraction-before-destruction’ technique on biological samples, where we’re able to measure a sample before the powerful pulses of the LCLS damage it.”

The scientists selected lysozyme as the first sample for their research because it is easy to crystallize and has been widely studied. Their research not only determined lysozyme’s structure at such high resolution that it showed individual amino acids, but also demonstrated the ability to utilize very small crystals for a range of applications. Dr. Boutet reported that the team has also studied more complex proteins and systems that they are analyzing now.

Ultimately, scientists using LCLS are driving toward an atomic- and molecular-scale understanding of complex biologic systems--such as the membrane proteins that are critical in cell functions and the processes that fuel photosynthesis--which could lead to findings in a range of sciences, from pharmaceutical advances to new sources of alternative energy.

The experiment was the first study performed on the new coherent X-ray imaging (CXI) instrument, a “molecular camera” designed, constructed, and commissioned by SLAC and now available to the scientific community. Also key to the study was a novel custom-made detector, the Cornell-SLAC pixel array detector (CSPAD), developed in collaboration between Cornell University (Ithaca, NY, USA) and SLAC for use at the CXI instrument. “This important demonstration shows that the technique works, and it paves the way for a lot of exciting experiments to come,” concluded Dr. Boutet.

Related Links:

SLAC US National Accelerator Laboratory


WATERS CORPORATION

Channels

Genomics/Proteomics

view channel
Image: Electron micrograph of Hepatitis C virus purified from cell culture. Scale bar is 50 nanometers (Photo courtesy of the Center for the Study of Hepatitis C, the Rockefeller University).

Oxidized LDL Predicts Response to Interferon Treatment of Chronic Hepatitis C and May Be a Treatment Option

Oxidized low-density lipoprotein (oxLDL) in the blood was shown to predict responsiveness to interferon treatment in patients with chronic Hepatitis C virus (HCV) infection and to inhibit spread of the... Read more

Drug Discovery

view channel
Image: Molecular model of the anti-cancer drug 5-fluorouracil (Photo courtesy of Wikimedia Commons).

Novel Microcapsule Approach Reduces Toxic Side Effects of Chemotherapy

Cancer researchers have reduced chemotherapy's toxic side effects by using nanoporous capsules to transport an enzyme to the site of a tumor where it is activated by a selective heating process to convert... Read more

Business

view channel

NanoString and MD Anderson Collaborate on Development of Novel Multi-Omic Expression Profiling Assays for Cancer

The University of Texas MD Anderson Cancer Center (Houston, TX, USA) and NanoString Technologies, Inc. (Seattle, WA, USA) will partner on development of a revolutionary new type of assay—simultaneously profiling gene and protein expression, initially aiming to discover and validate biomarker signatures for immuno-oncology... Read more
 

Events

02 Jun 2015 - 03 Jun 2015
15 Jun 2015 - 18 Jun 2015
Copyright © 2000-2015 Globetech Media. All rights reserved.